Selective catalytic reduction (SCR) is the most mature technology for flue gas denitrification in power plants, and the catalyst is the core. Arsenic poisoning is one of the most important sources for the deactivation of the catalyst. This review summarizes the physical and chemical deactivation mechanisms of the arsenic poisoned SCR catalysts. The physical deactivation is attributed to the deposition and oxidation of gaseous arsenic oxides over the surface of the catalysts, and the chemical deactivation is ascribed to the destruction of active acid sites caused by the arsenic species. Then, the development of SCR catalysts with the capability of anti-arsenic poisoning is presented, including the adjustment of the pore structures in the catalyst, optimization of the chemical formulation of the catalyst, and solidification of gaseous arsenic oxide. MoO₃ is the optimal active agent, metal ions such as Bi, In, Sn and Mg are the main additives for anti-arsenic poisoning, and Ca species is the effective sorbent for the gaseous arsenic species. Finally, the regeneration technologies for poisoned catalysts are briefly discussed, including the wet-solution washing, thermal reduction and the combination of multiple regeneration methods, among which the combination of mechanical blowing, wet-solution washing and active components implantation is widely utilized in the industrial processes at present. This review can provide fundamental instructions for the development of SCR catalysts for anti-arsenic poising.

The structure optimization of heat exchanger is of great significance for improving the equipment efficiency and alleviating the problem of energy shortage and waste heat in chemical machinery, electric power engineering, aerospace engineering and other industrial fields. In recent years, based on the surface morphology of organisms and their functions, the application of bionics theory to develop heat transfer enhancement and drag reduction techniques has been outstanding. In this paper, the research progresses on strengthening single-phase, phase change heat transfer and groove, dimple, convex, superhydrophobic surface drag reduction technologies with bionic structure as the reference for optimal design were mainly summarized. Heat transfer enhancement and flow drag reduction mechanisms of various biomimetic structures were analyzed and concluded. Combined with the development trend of efficient heat transfer at micro-scale, it was pointed out that the research on biomimetic structures at micro-scale was still in the stage of simplified shape imitation. The direction of structural optimization was not clear. The influence of structural parameters and the heat transfer enhancement and flow drag reduction mechanisms have not been agreed. Based on the micro-scale convective heat transfer with high resistance, the necessity of coupling bionic structure design for high efficient and drag-reducing and comprehensive performance researches were proposed, which provides beneficial guidance and development direction for the optimization design of microchannel.

In view of the problems of inconsistent criteria for determining fluid flow regime and poor agreement of prediction models in high-speed rotating flow field, according to the basic principles of fluid mechanics and the determination methods of pipe and clearance flow field, the classical one-dimensional Reynolds number and two-dimensional flow factor prediction models are reconstructed theoretically. Meanwhile, an ellipsoid determination model suitable for determining and predicting fluid flow regime in rotating flow field is proposed. Firstly, according to the classical Reynolds number model and flow factor model, the simulation calculation method and ellipsoid model are theoretically verified. Secondly, the velocity field under different media and working condition parameters is analyzed, and the results are compared with the relevant literature. Finally, the rationality and scientific of the ellipsoid model are demonstrated based on the theoretical analysis of the turning point in the rotating flow field. The selection of velocity components in the model and the differences produced are discussed. The results show that the prediction results of the pipe flow based on the ellipsoid model are completely consistent with the classical Reynolds number model, and the predicted values of the transition point in the rotating flow field by the new model is obviously lower than that of the traditional model, which is closer to the actual working condition. When determining the flow regime of the rotating flow field according to the ellipsoid model, the linear velocity at average diameter should be selected for average shear velocity, the average value of inlet and outlet radial velocity for radial average velocity and the maximum axial velocity for the input factors of the model. The proposed ellipsoid model provides a new idea and method for determining the flow regime scientifically in the theoretical calculation of rotating flow field.

A visualization study of the evaporator and compensator for the loop heat pipe (LHP) was conducted to explore the influence of different heating methods on the startup and stability characteristics of the LHP. The performance of an R245fa charged LHP with 50% liquid filling rate under three methods of heat load application was investigated: heating at the top of evaporator, heating at the bottom of evaporator, and heating both the top and bottom of evaporator at the same time. According to the main phase change modes in the cavity of the evaporator during the startup process, three startup modes were characterized: evaporation startup mode, evaporation-boiling mixed startup mode, and boiling startup mode. The results showed that the startup process in the latter two startup modes was faster when 5W of heat load was applied, and there were bubbles overflowing from capillary vapor channels of the evaporator cavity. The startup time was 760s and 1180s, respectively, far less than 2370s for the evaporation startup mode. The startup time of LHP was closely related to initial liquid level and the average liquid disappearance rate in the evaporation cavity. Additionally, the bubble growth in the cavity under different starting modes was explored. With the same heat load, the thermal resistances of the LHPs and the liquid height in the compensator under different heating methods were different. The LHP with the bottom heating method had the smallest thermal resistance. It is found that different heating methods affect the evaporation efficiency of liquid working in the evaporator. Meanwhile, it also could change the liquid height in the compensator and the heat leakage from the evaporator to the compensator, thus affecting the performance of the LHP.

The performance of the conical cross flow plate was tested in a pulsed extraction column of 75mm inner diameter, and the effects of pulsed intensity and superficial velocity of both liquid phases on hold-up and characteristic velocity were investigated under no-mass transfer using two systems: kerosene-water and 10% tributyl phosphate in kerosene-water. The results show that the hold-up is approximately proportional to the dispersed phase velocity, while the effects of continuous phase velocity have little impact under experiment operating range. With the increase of pulsed intensity, the hold-up first reduces and when the pulsed intensity reaches the critical value (Af)_t, the hold-up increases rapidly. Compared with the critical value of pulsed sieve plate column, and the two systems decrease about 9.7% and 41.4%, respectively. Moreover, the characteristic velocities decrease with increasing pulsed intensity and the characteristic velocity of the system with lower interfacial tension decreases faster. Based on the analysis of the experimental results, empirical correlations of hold-up and characteristic velocity are proposed by dimensional analysis method, and a good agreement between the experimental values and the predicted values from empirical correlations is proved with the maximum relative errors less than 20%, which can be used for the design calculations of pulsed extraction column.

The optimization of the thermodynamic performance of the CO₂ transcritical heat pump system often increases the initial investment cost of the equipment, and its impact on the overall cost during the equipment life cycle is unclear. In this paper, thermodynamic and economic models of conventional CO₂ transcritical heat pump system (BASE), CO₂ two-stage compression heat pump system (TSCHPS), and CO₂/CO₂ mechanical subcooling heat pump system (MSHPS), were established. In the economic model, the objective function was defined via considering the initial investment and operation cost of the equipment. The relationship between the thermodynamics and economy was studied through using three heat pump systems with small temperature difference fan-coil unit (STD-FCU), floor-coil radiator (FCR), and traditional designed radiator (TDR) as heat dissipation terminals. The economic change during the life cycle after the system upgrade was discussed. The results showed that the COP of TSCHPS and MSHPS were both improved by over 15% than that of the BASE system under the system nominal conditions of the three heat dissipation terminals, but their life cycle economy is not necessarily improved. There is a correlation between the thermodynamic performance and economy of the BASE system, but the correlation between the thermodynamic performance and economy of TSCHPS and MSHPS is not strong. The economic change after the system upgrade is related to the evaporation temperature and heat capacity, and the best economic system in different application ranges under three heat dissipation terminals is provided.

Trimethoxysilane is an important intermediate for the synthesis of functional organosilicon compounds. In the industrial process of catalytic production of trimethoxylsilane, a maximum-boiling azeotrope of trimethoxylsilane and methanol can be formed due to the excessive methanol. Three processes, pressure-swing distillation, extractive distillation, and extractive dividing-wall column, were explored for the separation and purification of methanol and trimethoxysilane in this study. The processes were optimized in terms of the minimum total annual cost (TAC) through using the mixed integer nonlinear programming (MINLP). The corresponding exergy efficiency and carbon dioxide emissions were investigated. The results showed that the extractive dividing-wall column process had obvious advantages, comparing with the pressure-swing distillation. The TAC used for the separation of 100kmol/h methanol (molar ratio 50.00%) and trimethoxysilane decreased by 50.25% , accounting for a range from 198.84×10⁴USD/a to 98.93×10⁴USD/a. Meanwhile, the exergy efficiency was increased from 8.17% to 13.82%, and carbon dioxide emissions are decreased from 1217.53kg/h to 684.22kg/h, resulting in a decrease of 43.80%.

Non-Newtonian gas-liquid two-phase flows exist widely in industrial and agricultural processes. The interaction between bubble and liquid phases is very complicated, which has the important influence on the transfer efficiency between phases. To understand hydrodynamic properties of bubbles in shear-thinning fluids, based on the continuous surface tension model and the Carreau constitutive model, the volume of fluid (VOF) method was used to numerically investigate the single bubble dynamics in the shear-thinning fluid. The present results showed that, the hydrodynamic characteristics of bubbles are closely related to the characteristic time λ of the liquid phase. The stronger the shear thinning degree of the liquid phase (the smaller rheological index n) or the smaller the surface tension (the larger E?tv?s number Eo) is, the more obvious the effect of λ on bubble deformation and wake vortexes is. Under the same shear-thinning degree and the surface tension, the larger λ is, the higher the terminal velocity of the bubble is, and the size and strength of the wake vortex is, resulting in the wider ranges of the high shear rate region and the low apparent viscosity region around the bubble. In addition, for different degrees of shear thinning, at the conditions of low surface tension, there is a viscosity blind region at the tail of the bubble, and with the increase of the λ, the viscosity blind region gradually breaks away from the bubble and breaks up; the viscosity blind region reduces the region of the low apparent viscosity around the bubble, increases the friction drag during the floating process of the bubble, and also reduces the bubble terminal velocity.

In order to prove the influence of wax crystal precipitation on the phase equilibrium and nucleation characteristics of hydrate formation, this paper selected a mixed solution of 2^# industrial white oil and 60^# Kunlun paraffin to simulate the wax-containing system. Using a high-pressure visual stirred tank and combining with the visualization images during the hydrate formation process, we studied the influence of different wax concentrations on the hydrate formation phase equilibrium curve, hydrate nucleation induction time, and induction time change rate, and explored the effects of wax crystal precipitation on hydrate generation mechanism. The results show that as the concentration of wax crystals increases, the phase equilibrium conditions for hydrate formation gradually decrease, and the phase equilibrium curve shifts to the right compared to the wax-free system; the greater the wax crystal concentration, the more obvious the tendency to shift; at 281.5K and the wax content of 3.5%(mass fraction), the phase equilibrium pressure decreases by 6.5% compared with that of the wax-free system. By analyzing the effect of different wax crystal concentrations on the hydrate nucleation induction time, it is found that the precipitation of wax crystals accelerates the hydrate crystallization, shortens the hydrate nucleation induction time, and the greater the wax crystals concentration, the more obvious the shortening of the induction time. By exploring the effect of different wax crystal concentrations on the hydrate nucleation-inducing ability, it is found that with the increase of wax crystal concentration, the promotion ability of wax crystal precipitation to hydrate-induced nucleation increases at first and then decreases. By analyzing the influence of wax precipitation on the hydrate formation rate and location, it is found that when the system reaches the hydrate formation condition, the hydrate in the center of the reaction reactor is generated earlier than at the gas-liquid surface and the kettle wall. The research results are helpful to the application and development of deep sea-oil and gas exploitation, and provide reliable pVT data for studying the coupling characteristics of wax crystal and hydrate.

Co-pyrolysis of coal and plastics can recover the hydrocarbon resources in waste plastics and realize the harmless treatment of waste plastics, so it is a promising way to recycle waste plastics. In this paper, the pyrolysis characteristics and product properties during co-pyrolysis of coal and plastics were summarized, and the mechanism of co-pyrolysis and the transformation of chlorine during co-pyrolysis were analyzed. Furthermore, the different mixing modes of coal and plastics and their influence on co-pyrolysis characteristics were introduced. The co-pyrolysis of coal and plastics has obvious effect on increasing oil and reducing water. Adding a certain amount of waste plastics in the process of coal pyrolysis can improve the quality of tar, and impact the structure and reactivity of pyrolysis semicoke. Therefore, co-pyrolysis of coal and plastics is a green and efficient method to manage waste plastics, which is of great significance to recover waste plastics, solve white pollution problem and improve the utilization efficiency of coal.

Natural gas is a green and efficient energy source, which has taken an increasing part of energy structure in China. Since natural gas contains a certain amount of toxic and harmful gas, hydrogen sulfide, it needs to be desulfurized before its utilization. Biological desulfurization is a process in which sulfur compounds are removed from gas and wastewater using microorganisms. Biodesulfurization is a simple process that has mild operating conditions, low energy consumption, less environmental pollution, high desulfurization efficiency and sulfur by-products. Therefore, the biological desulfurization technology has been one of research spots in the natural gas sweetening process. The review briefly summarizes the main sources of hydrogen sulfide in natural gas and natural gas desulfurization technologies used widely in industry, and then mentions the main bacterial strains used for biological desulfurization and their desulfurization metabolic pathways. Herein, the typical process and new process of natural gas biological desulfurization technology are described emphatically. Finally the developing trends of natural gas biological desulfurization technology are pointed out.

Biodiesel produced by microbial oils is a renewable alternative energy of traditional fossil fuels, and oleaginous yeasts are promising oleaginous microorganisms. Glucose is the most widely studied carbon source of oleaginous yeasts, however, its cost is too high to develop its large-scale applications. Thus, it is crucial to develop low-cost carbon source. Based on analyzing the metabolic mechanism of lipid synthesis of oleaginous yeasts, this article focuses on the advances of four cheap raw materials utilized by oleaginous yeasts: lignocellulose, crude glycerol, organic wastewater, and volatile fatty acids to synthesize microbial lipids. The enhancement or inhibition of the complicated components of these industrial and agricultural by-products on the cell growth and lipid synthesis of oleaginous yeast are discussed respectively. Subsequently, feasible solutions, such as efficient pretreatment of raw materials, genetic engineering to modify yeast, and co-culture with microorganisms are summarized. Finally, the advantages of oleaginous yeast utilizing low-cost substrates to synthesize lipids are clarified, solutions to conquer the inhibition of complicated components and high organic matter concentrations are proposed, and the future research is prospected. This review is beneficial to further promote the applications of low-cost substrates for oleaginous yeast to synthesize lipids and the development of renewable energy technologies.

The target product bio-oil from biomass pyrolysis is difficult to be directly applied due to its high oxygen content and complex components. Deoxidization and upgrading of bio-oil can be realized by upgrading pyrolysis steam with suitable catalyst. Based on the previous studies, this paper firstly summarized the structural characteristics, catalytic principle and catalytic effect of metal oxides as well as zeolite catalysts in catalytic pyrolysis of biomass. Then, the construction principle and catalytic mode of micro-mesoporous composite together with metal oxide/ZSM-5 composite dual catalytic system were introduced in detail, as well as their influence on the product distribution of biomass catalytic pyrolysis, and the feasibility and practicability of dual catalytic system were also illustrated. At the same time, other factors including raw material characteristics, process parameters and operation working mode which affected biomass catalytic pyrolysis were summarized. Finally, in view of the existing problems in research and development of dual catalytic pyrolysis, the prospect of the comparative study of different dual catalytic modes, improvement of dual catalytic system to reduce production costs, and exploration of the multiple use values of dual catalyst were put forward.

Biomass has received widespread attention as the only carbon-based renewable energy. Unfortunately, due to its high moisture, high oxygen content and low calorific value, direct conversion of biomass via pyrolysis or gasification is still encountering a number of issues, such as low conversion efficiency, high tar content and low calorific value of gas product. Pretreatment of biomass material by torrefaction exhibits a positive effect on improving the characteristics of feedstock and promoting the pyrolysis/gasification process. In this paper, the effect of torrefaction on the hydrophobicity, grindability, element composition, and energy density of cellulosic biomass feedstock, as well as the gas compositions, tar components, and calorific value of gas produced from pyrolysis/gasification are comprehensively reviewed. After torrefaction, the quality of the biomass materials is improved with enhanced hydrophobicity and grindability, and higher calorific value. At the same time, the pyrolysis/gasification performance of cellulosic biomass also can be promoted by torrefaction pretreatment, with higher combustible gas content, yield, and calorific value in gas product, as well as lower tar content. All these endow gas product with promising combustion performance and quality. Further researches on the coupling technology and application pattern of torrefaction and pyrolysis/gasification process should be carried out to improve the total economy and product added value for biomass conversion.

Thermal performance of organic Rankine cycle (ORC) exists optimum condition with the maximum or monotonic increase according to the temperature relation between low grade heat source and the critical temperature of working fluids. Performance with monotonic increase is better than that with optimum condition.This difference is caused by the location of the pinch point of heat transfer (PPHT) in the heating process, which causes the difference of the heat addition in the ORC. Based on this consideration,a new approach of adjusting PPHT in the heating process is proposed in order to increase the heat addition and net power output of the cycle. Accordingly, a configuration of ORC with ejector (EORC) is designed to demonstrate the adjustment of the PPHT to improve the thermal performance. Moreover, this adjustment of PPHT can enhance the matching of heat transfer of the heating process, or reduces the irreversibility of the heat transfer. Results show that the increment of the maximum net power output with R245fa can reach 34.99% to 22.57% in heating water temperature range of 100℃ to 160℃ by EORC compared with ORC. At heating water temperature 120℃, the maximum net power output of mixture R134a/R245fa (0.7∶0.3) is 7.12% and 9.45% higher than that of R245fa and R134a in EORC, respectively.

Microchannel heat exchanger has a broad application potential due to its advantage of high heat and mass transfer efficiency induced by its large surface to volume ratio. In order to enhance flow boiling heat transfer in a micro evaporator, a novel top-connected microchannel (TCMC) evaporator with micro/nano coatings on the microchannel surfaces was designed and fabricated by using electric brush plating method. The microchannel evaporator consists of eleven parallel microchannels with a cross section of 400μm×400μm. The height of the top connected zone is 400μm. An experimental investigation was conducted comparatively to find the heat transfer performance of the three test sections, including regular microchannel (RMC), top-connected microchannels (TCMC) and top connected microchannels with Ni/Ag compound coatings (TCMC-Ni/Ag). It indicated that the TCMC-Ni/Ag had the largest local heat transfer coefficient of 179.84kW/(m²·K), which was 4.1 times that of the RMC. It disclosed that the highly hydrophilic surfaces with Ni/Ag micro/nano compound coatings enhanced not only the bubble nucleation density but the bubble generation frequency by high-speed flow visualization. In relatively low and medium heat fluxes, the vapor phase formed by the coalescence of detached bubble tended to aggregate in the top connected zone, while the bubble nucleation was still maintained on the heated microchannel surface. Under high heat fluxes, the strong capillary suction of the highly hydrophilic surfaces (TCMC-Ni/Ag) resulted in the heat transfer mode of thin liquid film convective evaporation, which was the main mechanism for the contribution to the great improvement of heat transfer performance.

In order to solve the problem of low heat transfer power of deep borehole heat exchanger, a single-well enhanced geothermal system (SEGS) was proposed. The SEGS enhances heat transfer capacity of a single geothermal well by establishing artificial heat storage around the borehole. The performance of SEGS used in building heating was studied by numerical simulation. The results showed that SEGS has the best heat transfer effect when the heat transfer fluid was arranged in the flow direction from the inner tube to the outer tube, the average heat transfer power of a single well heating system is 1603.6kW, which is 2.2 times of the deep borehole heat exchanger.The heat transfer power of SEGS increases with the increase of artificial heat storage radius. When the artificial heat storage radius increases from 50m to 90m, the average heat transfer power increase brought by every 10m increase in radius is 102.7kW, 67.0kW, 43.8kW and 29.2kW, respectively.With the increase of the thickness of artificial heat reservoir, the heat transfer power of single well presents a trend of first increased and then slightly decreased. Considering the initial investment, it is suggested that the thickness of artificial reservoir should be designed as 400m.The heat transfer power of SEGS increases with the decrease of inlet temperature and the increase of inlet flow. For parts with SEGS depth less than 1500m, the insulation of the outer tube should be considered.

Propylene dimerization is an important reaction for producing terminal alkenes, including 4-methyl-1-pentence and 1-hexene, which are widely used as special polymer monomers, gasoline additives, and organic intermediates in chemical industry. The conversion of propylene and the product selectivity are largely determined by the catalysts used in the propylene dimerization. Heterogeneous catalysts have attracted wide attentions due to their advantages of easy recovery and relatively small environmental pollution, compared with homogeneous catalysts. Based on different reaction mechanisms, the solid base catalysts and solid acid catalysts used in the propylene dimerization have been systematically reviewed. The development and industrial applications of solid base catalysts in propylene dimerization have been introduced and their reaction mechanisms have been summarized by taking alkali metal potassium as an example. The solid acid catalysts of phosphoric acid catalyst, molecular sieve catalyst and transition metal catalyst are introduced in detail. In view of the harsh preparation conditions of solid base catalyst, we proposed a new idea to improve the catalytic unit. To increase the insufficient selectivity of solid acid catalysts, we pointed out that the reaction mechanism should be further studied and the catalyst combining acid carrier and transition metal should be designed reasonably to achieve high selectivity of the dimer products.

Ferrocene and its derivatives are good burning rate catalysts for composite solid propellant. The combustion performance of composite solid propellant can be controlled by adding a small amount of ferrocene derivatives. However, ferrocene-based catalysts with simple structure and small molecular weight have the disadvantages of easy migration and volatility, which seriously affect the storage life, service reliability and environmental adaptability of propellant charges. Therefore, the design and synthesis of ferrocene-based catalysts with low migration, low volatility and high catalytic efficiency have become the key points in this field. In this paper, the synthesis methods of new ferrocene-based burning rate catalysts, and their anti-migration, anti-volatility and catalytic performance reported in recent years are introduced. The existing problems are pointed out, and the future research direction in this field is prospected. The synthesis of ferrocene compounds with low molecular weight is relatively simple, and its catalytic performance is excellent, but migration and volatilization still exists. On the other hand, ferrocene polymer has large molecular weight, which can completely avoid the migration problem, but its catalytic efficiency is low, and the synthesis process is complex. Among these new burning rate catalysts, energetic ionic ferrocene-based compounds have low migration volatility and good thermal stability, and are easy to synthesize and modify. Moreover, their high nitrogen content is conducive to improve the energy level of propellant, so they have broad application prospects.

SiO₂ supported cesium catalyst was prepared and its performance in the aldol condensation of formaldehyde and methyl propionate was studied in a fixed-bed reactor. X-ray diffraction, field emission scanning electron microscopy, X-ray fluorescence spectroscopy and thermal analysis were used to determine the composition and structure changes of the catalyst. The conversion of methyl propionate of 13%~15%, that of formaldehyde of 60%~65%, and the selectivity to MMA based on methyl propionate of 93%~95% were achieved. During the reaction, the crystal structure and morphology of the catalyst did not change significantly with insignificant aggregation and loss of the active component Cs and the amount of carbon deposition increased. After in-situ regeneration by carbon burning, the catalytic activity was restored, and the initial activity was even higher than that of the fresh catalyst. With the progress of the reaction, formaldehyde and methyl propionate conversions approached the average level before regeneration. For a long-term run for about 1700h, the MMA selectivity based on methyl propionate maintained at 93%~95%. Technical and economic analysis showed that the new coal-based MMA synthesis route with the core step of aldol condensation is safer, more environmentally friendly, more economical and more efficient than the traditional routes of acetone cyanohydrin and isobutylene oxidation, and hence is quite suitable for using in China, which has rich coal, lean oil, and little gas in resource structure. The route fits the national coal chemical policy, which not only can break through the patent blockade of C2 and C4 routes so as to change the existing technology pattern of the MMA industry, but also can provide an important way for coal chemical companies to enter the MMA synthesis technology field to enrich the coal chemical product chain by consuming the excess production capacities of formaldehyde, acetic acid and a large amount of low-value by-product methyl acetate.

A series of Zn(Al)O composite oxides supported Au catalysts were prepared by deposition-precipitation with urea. Interestingly, the catalysts with varied Zn/Al molar ratios showed different catalytic performance for selective catalytic oxidation of glycerol to 1,3-dihydroxyacetone (DHA) without base. The physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), CO adsorbed Fourier transform infrared (FTIR) spectroscopy. The results showed that the molar ratio of Zn/Al in the Zn(Al)O composite metal oxide affected the content of the reactive oxygen species and in turn the catalytic activity of glycerol oxidation. When the molar ratio of Cu/Al reached 7∶1, the supported catalyst showed the best performance, i.e. the conversion of glycerol and product selectivity of DHA reached 58.5% and 95.3% respectively with the initial O₂ pressure of 10bar, at 80℃ for 2h. Then, the Au/Zn(Al)O-7∶1 catalyst was used to investigate the effects of reaction temperature, reaction time, reaction pressure and calcination temperature of supports on the catalytic oxidation of glycerol and the selectivity for DHA. Additionally, we also studied the stability of the Au/Zn(Al)O-7∶1 catalyst and discussed the deactivation reasons.

In China, eight big refining and chemical bases have been built and in production in recent years, so the production of C₉ aromatics will increase significantly in the future. Large refineries need to focus on how to process C₉ aromatics efficiently. In this paper, C₉ aromatics from reformer are used to produce BTX and durene by hydrocracking ＆ hydroalkylation. The reaction conditions are mild and the products are of high economic value with high selectivity. Under the optimum reaction conditions, the average yield of oil is 86.94%, in which the average content of C₅ ~ C₉ fraction (rich in BTX ) is 80.93%, the average content of durene is 12.98%, and the average content of C{}_{\mathrm{10}}^{+} fraction (excluding durene) is 6.09%. For the plant with an annual capacity of processing 90000 tons C₉ aromatics, an annual profit of 55.435 million yuan can be realized. The processing route proposed in this paper has high technical feasibility and economic feasibility, and is in line with the development trend of refining and chemical integration, therefore it is one of the preferred ways to process C₉ aromatics in the future.

A series of ZrO₂-Al₂O₃ composite oxides with different Al₂O₃ contents were prepared by coprecipitation method. Then, the catalytic performance of these catalysts in the process of transesterification of propylene carbonate (PC) and methanol to synthesize dimethyl carbonate (DMC) was investigated in the catalytic distillation experiment. The catalysts were characterized by XRD, FTIR, XPS, CO₂-TPD and NH₃-TPD. The results show that the presence of acid-base sites on the catalyst surface is the key factor for the restriction of the transesterification of PC and methanol. Different from ZrO₂ or Al₂O₃ single metal catalysts, the synthesized ZrO₂-Al₂O₃ catalysts form a stable solid solution structure. The amount of weak acid increased and strong base sites were produced on the catalyst surface. Data analysis shows that when the content of strong base and weak acid on the surface of the catalyst is high, its catalytic activity is high, indicating that the reaction has a synergistic catalytic effect of acid and base. When the Zr/Al ratio is 1, the contents of weak acid and strong base reach the maximum level, and the conversion and DMC selectivity of PC can reach 98.14% and 99.96%. After 12 cycles of recycling, the catalyst still has high activity and presents remarkable good structural stability.

Magnetic hollow microsphere has the prominent application in functional adsorption, immobilized carriers of enzyme, separation and purification of substances, encapsulation and controlled release of active substance and medicine, targeted drug delivery, contaminant prevention, food and material science. The article summarizes the preparation principle of magnetic hollow microsphere by bio-template method and research achievement, and mainly analyzes the two preparation technologies, soft template method and self-template method. Soft-template technologies adopt adsorption-calcination method for obtaining stable shapes of the microsphere when removing template materials. Self-template technologies adopt the methods of hydrothermal carbonization or calcination under the protection of inert gas to create special groups on the surface of hollow microsphere and hollow spherical structure which cause the magnetic substances to be adsorbed on and enter into the microspheres, and they can be classified as hydrothermal carbonization method and dipping-calcination method. Besides, the adsorption of magnetic substances on the surface of pretreated bio-template is another way, such as adsorption-coprecipitation and calcination-coprecipitation. In conclusion, the conditions of preparing magnetic hollow microsphere by bio-template are gentle and non-contaminant, and moreover, bio-template materials are nontoxic, so it will have the wide application in food processing and pharmaceutical industry.

Superhydrophobic surfaces have shown good application prospects because of their excellent properties. However, the super hydrophobicity will be lost if superhydrophobic surfaces are damaged by external mechanical forces and chemical erosion in practical applications. The superhydrophobic surface durability could be improved by endowing with self-healing property. In this study, the research progress of the fabrication and applications of the superhydrophobic surface with self-healing performance were described from the point of micro-nano structures and low surface energy materials. The self-healing behaviors and characteristics in relation to low surface energy materials of superhydrophobic surfaces caused by external factors, such as humidity, temperature, and light were introduced. Meanwhile, the restoring process of the microstructure of superhydrophobic surface mainly prepared by shape memory polymers was introduced. Besides, the applications of the superhydrophobic surface with self-healing performance in the fields of anti-corrosion, oil-water separation, and anti-icing were presented. Finally, the challenges and prospects of the development of self-healing superhydrophobic surfaces by optimizing surface structures and chemical compositions were discussed. It is of great significance to develop an environment-friendly superhydrophobic surface that can heal both the microstructure and low surface energy materials rapidly without external stimulation.

Due to the unique wettability, superhydrophobic surfaces have wide application prospects in industrial production and daily life. However, the monotonous superhydrophobicity is difficult to meet the application requirements in some harsh environments and emerging fields. In recent years, functional superhydrophobic surfaces combining superhydrophobicity with at least one kind of function such as repairability, transparency and electrical conductivity have become a research hotspot in this field. The research of functional superhydrophobic surfaces is of great significance in effectively prolonging service life and broadening application range in the emerging fields such as flexible electronics and quick deicing. In this paper, the basic theory of superhydrophobic surfaces was firstly introduced. Then, the research progress of functional superhydrophobic surfaces in recent years was reviewed, including the construction and application of functional superhydrophobic surfaces with repairability, stretchability, transparency, magnetism, electrical conductivity and asymmetric wettability. Finally, the existing problems in this field were summarized, including imperfect functionality, complex preparation process, high cost, environmental pollution and poor durability. It was pointed out that using simple and environmental method to develop functional superhydrophobic surfaces with long term usability would be the main development direction in the future. Meanwhile, attention should also be paid to promote the actual production and application of functional superhydrophobic surfaces.

Conductive hydrogels, a type of novel hydrogels which organically combine hydrophilic matrix and conductive medium, have plentiful insights and opportunities in flexible electronic devices and other fields because of their excellent flexibility, adjustable mechanical properties and outstanding electrochemical performances. In this review, the research frontiers and trends of conductive hydrogel materials were provided. The methods of classification and preparation of conductive hydrogels were introduced, and their design and performance of conductive hydrogels were discussed. Furthermore, the application research progress of conductive hydrogel materials was expounded thoroughly, and their problems and challenges were concluded. Finally, the development trend of conductive hydrogel materials was prospected, and it was pointed out that the use of natural raw materials in the exploration of conductive hydrogels with high conductivity, stable mechanical properties, extreme temperature tolerance, biocompatibility and biodegradability would be the focus of further research, while optimizing flexible electronic devices and improving the output stability of devices would also become an important research direction. The research on the fabrications and applications of conductive hydrogels can promote the rapid development of flexible electronic functional materials.

Nanofiltration (NF) membranes have attracted more and more attention due to their low operation pressure, high flux, separation selectivity and low operating costs. At present, NF membranes have played an important role in the desalination of brackish water, sewage treatment and desalination. As a commonly used method for the preparation of polyamide NF membranes, interfacial polymerization can effectively adjust the microstructure of the NF membranes by adjusting the polymerization process, which further has a significant influence on its separation performance. This article started with the structure of the composite NF membrane, and made a comparative summary of the popular modification methods to improve the performance of NF membranes, including the optimization of the separation selection layer, the construction of the intermediate layer and the adjustment of the support structure. During the course of the interfacial polymerization, the influence of reactive monomers, types of additives and preparation conditions, etc. on the separation layer structure and separation performance were discussed. The effects of physical and chemical properties such as the pore size, porosity and hydrophobicity of the supporting membrane on the performance of the composite membrane and the advantages and disadvantages of different types of intermediate layers were also analyzed. Finally, the current problems that need to be solved in the industry were summarized and the future development trend of NF membranes had been prospected.

The application of styrene (St) in the polymerization-induced self-assembly (PISA) at room temperature has been limited by the slow polymerization rate of St at ambient temperature. In this work, a simple PISA approach was proposed for poly(2-vinylpyridine)-block-polystyrene (P2VP-b-PSt) using blue LED as illuminant and avoiding employment of photoinitiators or photocatalysts. By using P2VP as macromolecular chain transfer agent, St as a monomer and methanol as solvent, nano-objects of poly (2-vinylpyridine)-block-polystyrene(P2VP-b-PSt) were successfully prepared at room temperature. The effects of the molar ratio of St to P2VP, polymerization time and chain length of P2VP on the aggregate morphologies were investigated. The results showed that the morphology of aggregate was transformed from spherical micelle to vesicle when the molecular weight of P2VP was 4000, the molar ratio of St/P2VP was varied from 400/1 to 4000/1 and the polymerization time was from 3h to 24h, while only spherical micelles were obtained when the molecular weight of P2VP was 8300.

Carbon steel is widely utilized in industrial and agricultural processes. The study and application of the smart coating provide a new approach for the corrosion protection of carbon steel. In this work, mesoporous silica nanocontainers (MSNs) with large pore size were synthesized by using tetraethyl orthosilicate (TEOS) as the reactant through the addition of the pore-expanding agent of 1,3,5-trimethylbenzene (TMB). The prepared MSNs were modified by poly(acrylic acid) (PAA) to obtain the intelligent nanocontainers of BTA@MSNs-PAA with pH-sensitivity. The structure and performance of BTA@MSNs-PAA were characterized by scanning electron microscopy (SEM), dynamic light scattering analysis (DLS), X-ray diffraction analysis, infrared spectroscopy (FTIR), thermogravimetry/differential thermal analysis (TGA/DTA), and ultraviolet-visible spectroscopy (UV-vis). Meanwhile, the smart coating was fabricated on carbon steel through the dispersion of BTA@MSNs-PAA into epoxy resin. The protective properties of the smart coatings were evaluated by electrochemical impedance spectroscopy and salt spray accelerated experiments. The results showed that BTA@MSNs-PAA presented a near-spherical and smooth surface with an average diameter of 320nm. BTA@MSNs-PAA could load BTA by electrostatic interaction between PAA and BTA molecules. The amount of BTA loaded in BTA@MSNs-PAA is up to 16.49%. The releasing rate of BTA from BTA@MSNs-PAA can be accelerated under acidic conditions. The prepared coating presents remarkable anti-corrosion performance for carbon steel in NaCl corrosion medium, which may be because the releasing of BTA from BTA@MSNs-PAA is triggered by corrosion-induced pH decrease. Therefore, it can prevent the further corrosion of carbon steel substrate.

A series of MoS₂/Y zeolite composites with different ratios were synthesized by hydrothermal method and made into the carbon-based composite electrolytic cell cathode. The LSV test showed that when the mass ratio of MoS₂ and Y zeolite was 5∶2 and the carbon paper loading was 1.5mg/cm², the cathodic hydrogen evolution performance was the best. The composites were characterized by SEM, TEM, XRD, XPS and BET. SEM testing indicated that the MoS₂/Y zeolite was a cloud-like morphology in which sheets and octahedrons were interwoven and superimposed. BET testing showed that it had a well-arranged micropore-mesoporous multi-level channel structure, which was beneficial to accelerate H⁺ reduction and H₂ diffusion. The hydrogen evolution performance of MoS₂/Y zeolite as the cathode of microbial electrolysis cell (MEC) was investigated. In the five-cycle hydrogen production experiment of MEC, the average maximum current density, hydrogen production rate and hydrogen production of MoS₂/Y zeolite were higher than that of Pt electrode, and had long-term stability. Therefore, MoS₂/Y zeolite was a suitable hydrogen evolution catalyst.

In order to obtain a humidity sensor with both good humidity response and color visibility, the CoCl₂/FP composite film was prepared by simple soaking-drying method using cellulose filter paper (FP) and cobalt chloride (CoCl₂) as raw materials, filter paper as the sensor's base material, and cobalt chloride as moisture sensitive material and color indicator. The physical and chemical properties of the composite films were tested by scanning electron microscope, Fourier infrared spectrometer and X-ray diffractometer. The results indicated that Cl and Co were uniformly distributed on the CoCl₂/FP composite film, and the main physical changes occurred between the filter paper and cobalt chloride. The current response and visible spectrum of CoCl₂/FP colorimetric humidity sensor were measured by electrochemical workstation and computer color matching instrument. The results showed that the CoCl₂/FP colorimetric humidity sensor had an obvious current response in the range of 11%~98%, and the current change was more than 1000 times. In addition, from low humidity to high humidity, CoCl₂/FP colorimetric humidity sensor presented a reversible color change from blue to red.

The defects of high cost and complex operation of conventional signal amplification strategies are adverse to their potential applications in early diagnosis and other fields. In recent years, a new kind of signal amplification strategies based on the use of controlled/“living” radical polymerization (CLRP) techniques such as atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization has been established for the simple, fast, low-cost, highly sensitive and selective detection of biological molecules (e.g., proteins and nucleic acids). In this paper, the research progress of the CLRP-based biosensing was reviewed. Firstly, the concept and characteristics of biosensors were introduced, as well as the pros and cons of the conventional and the polymer-based amplification strategies. Furthermore, the application of the ATRP-based and the RAFT polymerization-based amplification strategies in the highly sensitive biosensing was reviewed. Finally, the prospect of the CLRP-based biosensing was presented. By virtue of their advantages such as simple operation, low cost, and high efficiency, the CLRP-based amplification strategies show great potential in the highly sensitive detection of biological molecules.

Compared with other nanomaterials, Fe₃O₄ nanoparticles are widely used in enzyme immobilization, targeted drug delivery and nucleic acid extraction due to their unique magnetic properties. However, their applications in different aspects have different requirements on the size and morphology of the particles themselves. For example, the smaller Fe₃O₄ has the less side effects to the human body and is more promising for the effective targeted treatment of diseases. The precise control of the size and shape of the magnetite nanoparticles becomes particularly important in recent years. Therefore, this paper reviewed the traditional methods of preparing magnetic nanoparticles by co-precipitation, which require the use of organic solvents or high temperature control, and introduced the environmental pollution and safety problems existing in these methods. Besides, we expounded the new trend of the preparation of magnetic nanoparticles by biological macromolecule mediated biomimetic mineralization which is inspired by biomineralization in nature. Moreover, the latest research progress in protein (or peptide) mediated biomimetic mineralization for the preparation of magnetic nanoparticles was reviewed as well. The advantages and disadvantages of the methods in the size and shape control of magnetite (Fe₃O₄) nanoparticles, together with the challenges were also addressed.

The anammox process is a green and efficient novel technology for the biological treatment of nitrogen pollution in water. However, the long generation time of the anammox bacteria and its highly environment sensitivity characteristics result in the slow start-up of the anammox system and low operational stability, which further limits practical applications of the anammox process. Iron is not only a ubiquitous metal element in the environment, but also an essential nutrient element for microbial growth. In the anammox system, both the valence state and dosage of iron could affect the microbial activity and nitrogen removal performance. Here, the effects of iron on the start-up of the anammox process and the nitrogen removal performance in the operation process were reviewed. Furthermore, the reaction pathways of iron and nitrogen, the relationship between the growth rate of anammox bacteria and formation of the particles, and the composition of microbial communities, under the presence of iron are analyzed. It could help to further understand the role of iron in microbial nitrogen removal systems and the involved mechanisms. In addition, it provides scientific guidance for the enhancement of microbial nitrogen removal processes and improvement of microbial activity in the engineering application through the introduce of iron.

In order to improve pesticide utilization and control pesticide release, a pH responsive particle was designed. 3-aminopropyl triethoxysilane (APTES) was used as a bridge to connect carboxymethyl cellulose (CMC) and soybean protein isolate (SP). Avermectin (AVM) was hydrophobically encapsulated as a model drug to obtain CMC-SP@AVM. The chemical interaction between SP and CMC was confirmed by Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetric (DSC). Their structural characteristics and stability were investigated through scanning electron microscope (SEM) and zeta potential technique . It found that AVM encapsulated in CMC-SP@AVM particles with average size of 104nm. Ultraviolet-visible (UV-vis) spectroscopy was employed to explore the anti-UV property and encapsulation as well as release behavior, which revealed that the presence of CMC-SP@AVM protected AVM from UV photolysis with encapsulation efficiency of 41.9%. The residual rate of AVM in the CMC-SP@AVM was 117% higher than that of unsealed AVM after irradiating with strong ultraviolet light for 120h. The release rate of AVM was pH responsive. The higher the pH, the faster the release rate. It showed that the release of AVM from CMC-SP@AVM fit to the Elovich kinetic model. The insecticidal activity of CMC-SP@AVM is not significantly different from that of the original drug at the same AVM concentration.

The development of economical and efficient flue gas denitrification technology is an important research direction of air pollution control, in which microwave-induced catalytic denitrification has become a hotspot. This paper summarizes the research results of domestic and foreign researchers on microwave-induced catalytic treatment of NO_x in recent years, and introduces the related researches of microwave reduction denitrification and microwave oxidative denitrification, with the focuses on the usage of ammonium bicarbonate and activate carbon as reducing agent, and ZSM-5, metal oxide and perovskite-type mixed oxide as catalysts. Finally, it is proposed that the development of microwave catalytic oxidative denitrification and the exploration of its reaction mechanism are the important directions for the development of new flue gas denitrification technology.

Deep bed filtration is one of the most important parts in oilfield wastewater treatment. However, the key to its effect is effective backwashing. With the increasing concentration of polyacrylamide (PAM) in oily wastewater during the filtration process, the PAM in wastewater adsorbed in the filtration bed, adhered to the media surface, and formed larger lumps of media that were difficult to be separated. The filtration bed contained PAM could not be fully fluidized. This leads to poor media generation, packing together of filtration bed, reduction of filtration efficiency and even ineffective. In this paper, the media backwashing mechanism for deed bed filter under the gravity field was analyzed. The process of single water backwashing, water backwashing with air scouring, and other enhanced hydraulic backwashing methods were reviewed. A new method of backwashing in coupled field backwashing process was put forward, which could break through the technical bottleneck of low backwashing efficiency under gravity field, enriching and developing the hydraulic backwashing theory of filtration bed under the gravity field. Furthermore, it opened a new way for filtration bed backwashing in oilfield polymer flooded wastewater treatment.

Oily sludge in oil and gas fields is the main pollutant in the process of oil drilling, transportation, and storage. With the deepening development of oil and gas fields, the contradiction between oil production and environmental pollution is becoming increasingly noticeable. The original oily sludge treatment methods are no longer suitable for new environmental requirements. At present, physical and chemical treatment methods have initially achieved oily sludge reduction and crude oil resource recovery, but they cannot fundamentally remove petroleum pollutants in oily sludge, and may even cause secondary pollution. Biological treatment methods have the characteristics of low toxicity, environmental friendliness and high efficiency, as well as have extremely wide application prospects. In this paper, the origin, characteristics, treatment standards and environmental impact of oily sludge were briefly introduced. The biological treatment technology is divided into BSF oil washing and the biodegradation. The types and characteristics of BSF, oil washing mechanism, degradation process, degrading bacteria, influencing factors on treatment effect and BSF enhancing biodegradation were described in detail. BSF oil washing method is mainly applied to the treatment of oily sludge with an oil content more than 6%, and the oil content can be reduced to less than 2%. For oily sludge with an oil content less than 6%, the ecological standard of 0.3% can be reached by microbial degradation technology. Biological treatment technology is the most promising oily sludge treatment technology that can meet resource recovery and environmental protection.

The odor pollutants released during the operation process of wastewater treatment plants (WWTPs) affect the environmental quality of the surrounding air, which will lead chain hazards to human health, social stability, and economic construction. This paper introduced the recent development of the odor gases purification technologies in WWTPs, mainly focusing on the current application situation of biological deodorization technologies. Firstly, the deodorization principle, developmental history, main influence factors, and characteristics of biofiltration, bioscrubbing, activated sludge diffusion, activated sludge recycling, and oxidized ammonium recycling were introduced. Then the application cases of biological deodorization technologies in Chinese WWTPs were introduced, and the current application status was summarized. Finally, according to the comparison and current application status of biological deodorization technologies, the developmental trends of deodorization engineering in WWTPs were proposed, which included subarea treatment, combination of terminal treatment technologies and source emission reduction technologies, airtight treatment, and control of bioaerosols. This review could provide technical references for enhancing the environmental quality of Chinese WWTPs.

The conversion of waste plastics into high value-added products through pyrolysis and catalytic pyrolysis is a promising recycling way, which can solve the environmental pollution problem caused by waste plastics and promote environmental sustainability. This pyrolysis method has both economic benefits and obvious environmental advantages, giving the future development trend for the plastic recycling industry. Starting with the products of paraffin, light aromatics (BTX), low carbon olefin and styrene, this paper expounds the pyrolysis characteristics of different polyolefin plastics, and then introduces the effects of temperature and residence time on the product distribution and yield in detail. Based on the differences in the spatial structure of polyolefin, the pyrolysis mechanism of different catalysts was discussed, and the influencing factors such as the acid strength and pore structure of the catalyst were emphatically analyzed, so as to improve the product selectivity. Furthermore, three dechlorination processes of polyvinyl chloride are briefly described, namely pyrolysis dechlorination, catalytic pyrolysis dechlorination and adsorption dechlorination. Finally, the potential problems of high cost and low reuse activity in the catalytic pyrolysis process are pointed out. Future research should focus on optimizing the process and developing cheap catalysts.

Considering the complexity of volatile organic compounds (VOCs) treatment technology and the economic benefits in practical engineering applications, this paper introduces the main biological combined technologies, including UV photodegradation and biological process, non-thermal plasma and biological process, chemical and biological process, adsorption and biological process, combustion and biological process, and biological combination technology. The research progress and problems of biological combined technology are summarized. UV photodegradation, non-thermal plasma and chemical method are often used as pretreatment technology combined with biological technology, improving the overall degradation effect and making the bioreactor have better operating performance. The adsorption and the combustion method are usually combined as end treatment technology with biological method to ensure that the exhaust gas can reach the emission standards. In addition, the combination of different biological treatment technologies has formed a synergistic advantage, which makes it obtain better degradation results for industrial waste gas. It is pointed out that biological combined technology is a promising option in waste gas treatment. However, the research of biological combined technology is not deep enough, and its practical application is not mature enough, so it needs to be further explored.

As the major pollutants in air, volatile organic compounds (VOCs) have caused serious damage to the environment and human health. Due to its low cost and easy operation, the adsorption technology has been considered as one of the effective solutions for the enrichment of low concentration of VOCs in air. Zeolites have showed unique selective adsorption ability in molecular scale due to their highly ordered micropores with adjustable pore sizes and excellent thermostability, which allows them to be high-performance adsorbent candidates for VOCs. Besides, the selective adsorption behavior of the micropore zeolites was mainly decided by the types of framework topology and balanced cation. The enhancement in structural hydrophobicity of zeolites could effectively reduce the competitive adsorption between VOCs and water molecules under high humidity. By introducing macro-/mesopores into zeolite crystals or constructing hybrid adsorbents with macro-/mesopores materials, the obtained hierarchical porous adsorbents possessed much larger specific surface areas and total pore volumes, resulting in an increased adsorption capacity of VOCs. Zeolites were easy to process by extrusion or coating on shaped substrates, and the obtained monolithic adsorbents revealed higher mechanical strength and better abrasive resistance than the original powders. As a representative, zeolite adsorbent rotor, which was constructed by cellular zeolite monoliths, was successfully used for the effective removal of VOCs from industrial emissions.

With the increase of the production and usage of pharmaceutical and personal care products (PPCPs), the amounts and types of PPCPs as well as their metabolites detected in water and soil environment are increased. In this paper, the environmental risks of typical PPCPs entering the soil-crop system through different ways are summarized based on relevant literature. In addition, the latest research on environmental behavior and fate of PPCPs is reviewed from the aspects of PPCPs degradation behavior characteristics and the laws of migration and accumulation in the soil-crop system. It also points out the outstanding problems of PPCPs in the current research, such as the simplicity of PPCPs types, concentrations, input modes, and environmental backgrounds. The future research trends in this field are prospected, for instance, the environmental behavior characteristics of different types of PPCPs, the interaction mechanisms between PPCPs and soil microenvironment, degradation or chelation products, and their environmental behaviors and risks. This review is of great significance to investigate the influence of PPCPs on the ecological environment and its potential harm to human health.

In recent years, emerging contaminants such as PPCPs (pharmaceuticals and personal care products) and EDCs (endocrine disrupting chemicals) have been frequently detected in the environment, which has risen high concern. Many researches have shown that these emerging contaminants are ubiquitous in environmental media such as rivers, lakes, oceans, soil, sediments, and groundwater. Due to continuously discharged into the environment and hardly degradable characteristics, these emerging contaminants show a “pseudo-persistent” state in the water environment. These emerging contaminants cloud cause plenty of adverse effects on the ecological environment and human health. In this paper, the occurrence, fate distribution, and removal technologies of emerging contaminants represented by PPCPs and EDCs in the environment are briefly discussed. The distribution of PPCPs and EDCs in various countries and regions are summarized. At last, the present research situation of the removal of PPCPs and EDCs by biochar was introduced. The impact factors such as feedstock for biochar preparation, pyrolysis temperature, modification or activation methods, initial solution pH, ionic strength, and interferents were discussed. Finally, a summary and prospect were made to provide more ideas for the related research and application of biochar for emerging contaminants removal such as PPCPs and EDCs.

Experimental studies on landfill leachate treatment by evaporation, evaporation-vapor acid absorption, evaporation-vapor alkali absorption and evaporation-vapor acid absorption-vapor alkali absorption were carried out, and the effects of vacuum degree and initial pH of leachate on condensate water quality when using different processes were investigated. The results showed that when the evaporation process was adopted, as the vacuum degree increased, pH, NH₃-N concentration and TDS value in condensate all presented a downward trend, while COD concentration went up gradually. When the initial leachate was acidic, NH₃-N content in condensate was low, while COD content was high; when the initial leachate was alkaline, COD content in condensate was low, while NH₃-N content was high. The evaporation-vapor acid absorption process could efficiently reduce NH₃-N content in leachate, and the evaporation-vapor alkali absorption process could remove COD in leachate. The evaporation-vapor acid absorption-vapor alkali absorption process could simultaneously decrease COD, NH₃-N and TDS concentration in leachate. Under the initial pH 8.1 of leachate, the removal of COD, NH₃-N and TDS in leachate all exceeded 99%, and their concentration dropped below 60mg/L, 8mg/L and 10mg/L, respectively. The condensate quality complied with GB 16889—2008 discharge standard for environmentally sensitive areas.

In order to remove SO₂ from manganese slag calcination process, and combine with the production features of electrolytic manganese production enterprises, the manganese oxide ore was used as the raw material, and the wastewater anode solution of electrolytic manganese was used to prepare the ore pulp (desulfurizer). The influences of processing parameters and FeSO₄ added on desulfurization and manganese leaching were studied. The results indicated that the introduction of FeSO₄ promoted the Mn leaching via the redox reaction between MnO₂ and FeSO₄, and then, the product (Fe³⁺) and the Mn²⁺ in solution could act as the catalyst to catalyze the desulfurization reaction. The desulfurization activity and the Mn leaching rate increased with the decrease of the ore particle size. With the increase of reaction temperature, the desulfurization activity decreased, and the Mn leaching rate increased at first and then decreased which reached the maximum value at 60℃. When the liquid-solid ratio and the inlet flow rate increases, the desulfurization efficiency decreased, but the Mn leaching rate was enhanced. The 5-stage manganese oxide slurry desulfurization of the 7% flue gas with FeSO₄ added showed that the outlet SO₂ was 293μL/L, and the Mn²⁺ concentration of lixivium was 44.72g/L, which met the requirements of electrolytic manganese. The present flue gas desulfurization system could recycle the wastewater anode solution of electrolytic manganese, and provide a new technology for sulfur dioxide removal from flue gas and Mn extraction form manganese oxide ore simultaneously. The present study provides theoretical basis and technical reference for clean production and comprehensive utilization of resources in electrolytic manganese industry.

To bridge the gap between phosphonates being too much as the antiscalant used in industrial cooling water systems and phosphorus being too little as a resource, the electrochemical treatment process was developed for the recovery of phosphorus from the phosphonate wastewater. In this reaction system, boron doped diamond (BDD) mediated anodic oxidation was effective for the oxidative release of ortho-phosphate (o-PO₄) from phosphonates. At the same time, OH^- was generated by H₂O reduction at the cathode and created a basic environment near the cathode, where calcium phosphate would become highly supersaturated precipitated. In this study, the effects of operation parameters on ethylene diamine tetra(methylene phosphonic acid) (EDTMP) degradation and the recovery of phosphorus were investigated. It was found that the degradation of EDTMP was mainly attributed to the production of ?OH during the BDD mediated anodic oxidation process, which was much more favorable at higher current density. TOC removal efficiency, o-PO₄-P concentration and phosphorus recovery efficiency were increased from 14% to 72%, 6.5mg/L to 9.9mg/L and 21% to 83%, respectively, with current density increasing from 3mA/cm² to 30mA/cm². Phosphorus recovery efficiency was negligibly influenced by the variation of solution pH from 3.0 to 12.0. Increasing Ca²⁺ concentration could increase the recovery of phosphorus. Phosphorus recovery efficiency was enhanced from 46% to 83% with elevating Ca²⁺ concentration from 25mg/L to 100mg/L. In electrochemical reaction system, phosphorus was recovered at the cathode surface in the form of amorphous calcium phosphate with Ca/P molar ratio of 0.6.

Tetraethylenepentamine modified bentonite (TEPA/Bent) was prepared by grafting tetraethylenepentamine (TEPA) on the surface of bentonite (Bent). It was characterized and analyzed by using several methods, such as FTIR, XRD, EA, SEM and EDS. The adsorption performance of the anionic dye acid scarlet GR in water on the TEPA/Bent was investigated. The results showed that TEPA was successfully grafted on the surface of bentonite, which increased the adsorption capacity of acid scarlet GR. The pH had a greater impact on the surface potential and adsorption capacity of TEPA/Bent. As the initial pH increased, the zeta potential of TEPA/Bent was changed from positive to negative and the adsorption capacity of acid scarlet GR decreased. When pH=3 and the initial mass concentration of dye was 100mg/L, the adsorption capacity of TEPA/Bent for acid scarlet GR could reach 44.63mg/g. The adsorption kinetics followed the quasi-second-order kinetic model. The adsorption isotherms could be well fitted with the Langmuir model, which was a monolayer adsorption. The adsorption thermodynamics showed that the adsorption was a spontaneous endothermic process. After 5 times of regeneration of the adsorbent, the adsorption capacity remained above 80% of the original. This work indicateded that TEPA/Bent can be a potentially efficient adsorbent for the removal of anionic dyes from aqueous solution.

The microorganisms extracted from the substrate of constructed wetlands for treating Cd(Ⅱ) wastewater were screened through heavy metal concentration gradients. The analysis result of PCR technology showed that the screened bacteria had better tolerance and adsorption capacity for Cd(Ⅱ). The abundance of bacteria was Lactococcus<Stenotrophomonas<Serratia< Pseudomona. The screened bacteria were used to prepare the immobilized biosorbent by embedding and immobilization technology. The maximum removal efficiency of Cd(Ⅱ) could reach 91%±2% when pH, adsorption time, adsorbent dosage (wet weight), and initial concentration of Cd(Ⅱ) were 4—5, 48h, 50g/L, and 100mg/L, respectively. It was found that the adsorption process was in accordance with the quasi-first-order kinetic model and Langmuir model. The maximum adsorption capacity of Cd(Ⅱ) was 34.4mg/g. The BET analysis results showed that the immobilized biosorbent had a mesoporous structure and large specific surface area, which was conducive to the adsorption. The results of FTIR-ATR analysis showed that the immobilized biosorbent had abundant heavy metal binding sites, and —COOH, —OH, —NH, and —CH groups participated in the adsorption process of Cd(Ⅱ). The immobilized biosorbent could be reused for three times and maintain a good adsorption effect, which had a high economical practicability. The order of competitive adsorption of of common cations in water environment with Cd(Ⅱ) was Na⁺ <K⁺ <Ca²⁺.

This research was carried out with the purpose of exploring the application of the luffa in oil-water separation and to realize high-value utilization of the waste agricultural resources. Natural luffa was pretreated with alkali and hydrogen peroxide to remove its wax, increasing its specific surface area. Hydrophobic dispersion of nano-silica and MQ silicone resin was firstly prepared, then, hydrophobic/oleophilic luffa was prepared using pretreated luffa as a porous adsorption carrier by ultrasonic-assisted impregnation method. Its vegetable oil absorbency and water absorbency, the separation efficiency of the oil-water mixture, and reuse-ability to vegetable oil were measured. The experimental results show that the luffa has hydrophobic and oleophilic after dipping silica and MQ silicone resin dispersion, and its contact angles to water and oil reach 140.3°±6°and 0°, respectively. The absorption ratios for absorbing vegetable oil and water were found to be 4.86g/g and 0.28g/g. The separation efficiency of the modified luffa for oil and water reaches 76.5% and 95.5%, showing good oil-water separation performance. In addition, after 4 times of filtration, the network structure is destroyed and part of the hydrophobic layer is peeled off due to mechanical extrusion. Meanwhile, the oil absorption of luffa decreases, which impacts the reusability of luffa.

A process for copper extraction using cyclone electrowinning technology was carried out, based on the composition characteristics of the oxidation acid leaching solution of copper-cadmium residues. The effects of different cyclone electrowinning processes on the relevant technical parameters and impurity ions migration behavior in the electrowinning process were investigated. The advantages and disadvantages of different electrowinning processes were analyzed. The results show that the concentration of copper ion in the solution can be reduced from 44.14g/L to 1.42g/L by one-stage cyclone electrowinning. While, the end-point copper ion concentration in the solution can be reduced from 1.42g/L to less than 0.5g/L by segmented cyclone electrowinning. Additionally, the electrodeposition efficiency of copper ions on the cathode can be increased from 96.78% to 99.20% with the current efficiency increased from 90.52% to 98.49%. When the concentration of copper ion was reduced to 10g/L or less, the co-deposition of impurity ions and copper in the cathode is obvious. The gloss and morphology quality of the cathode copper products obtained by the segmented cyclone electrowinning process are better. Compared with one-stage cyclone electrowinning, the segmented cyclone electrowinning process has the advantages of high current efficiency, low energy consumption, and better product quality, etc.

Red mud is the biggest environmental pollution problem in alumina industry, and alkalinity regulation is the key to red mud disposal. The simulated solution of the CaCl₂ generated from the resource recycling process of red mud was selected as the agent to study the alkalinity regulation of red mud. Factors that may affect the alkalinity regulation were investigated. Column leaching experiments were conducted to simulate the leaching process in the actual red mud storage process, and pot experiments were carried out to evaluate the soil formation potential of dealkalized red mud. The results show that the pH of the leachate decreased to 8.39 and the concentration of Ca and Na ions reached 7.74g/L and 1.22g/L under the optimal conditions of solid-to-liquid ratio of 500g/L, Ca²⁺ concentration of 10g/L, reaction temperature of 85℃ and reaction time of 2h, respectively. In addition, the dealkalization equilibrium can be reached in one dealkalization process. The Na/Ca ratio of the column leaching effluent reached 107.8, which was much higher than that of seawater (25.8), suggesting that it could be used as raw materials for chlor-alkali industry. The pH of red mud decreased from 11.14 to 8.05 after dealkalization. The seven-day germination rate of ryegrass in the mixed matrix of dealkalized red mud and sawdust reached 92%, which was higher than that in fresh soil (84%), suggesting that dealkalized red mud is suitable for plant growth. In summary, the use of recycled CaCl₂ for red mud alkalinity regulation can provide a low-cost, green and environmentally friendly method for red mud disposal.

Environmentally persistent free radicals (EPFRs) are widespread in soil organic matter. There is still insufficient research about the relationship between its characteristics (signal strength, g-value and line width) and the structure of organic matter composition. In this study, humic acids (HAs) extracted from Heilongjiang black soil, Yunnan red soil and Shandong yellow soil were used as experimental samples. The signal characteristics of EPFRs in HAs were determined by electron paramagnetic resonance spectroscopy (EPR). Elemental analysis, ultraviolet spectrophotometry,¹³C NMR nuclear magnetic, high performance liquid phase and other methods were used to determine the structure, composition and molecular weight distribution of HAs. The results showed that the amount of EPFRs (0.84×10¹⁶—7.42×10¹⁶ spin/g) in HAs decreases with the increase of molecular weight. There were a significant positive correlation with the aromaticity of HAs (r=0.813, p<0.01), which is due to the fact that free electrons of aromatic compounds can partially separate domains to form EPFRs. The g values of EPFRs (2.0034—2.0041) decrease with the increase of aromaticity (r=-0.752, p<0.01). It was indicated that aromatic components have a major contribution to the carbon-centered free radicals. Compared with the soil in the other two regions, the EPFRs signal in Yunnan red soil with the rich Fe³⁺ content is the most stable. Under strong ultraviolet radiation in Yungui Plateau, it is more conducive to the formation of stable EPFRs. The present study is of great significance for understanding the environmental behavior of widely distributed EPFRs in soil.

Petroleum pyrolysis is an important step in the process of producing high-quality gas-liquid fuels and chemicals. It exists not only in the non-catalytic process, but also in the catalytic process, involving thermal cracking, coking, viscosity-reducing, high-temperature cracking, catalytic cracking, hydrocracking and dehydrocracking, etc. However, the reaction process and mechanism of petroleum pyrolysis process have not yet been clarified, and the experimental phenomena cannot be reasonably explained by the free radical chain reaction mechanism of thermal cracking and the positive carbon ion reaction mechanism of catalytic cracking. In this paper, it was proposed that the main body of chemical reaction in each process of petroleum pyrolysis was dominated by free radicals which were dissociated by heat. The difference between different pyrolysis processes mainly lied in the regulation of secondary free radicals. The free radical complex products and the stable products formed the product distribution of the specific pyrolysis process. The reaction mechanism was created of free radical regulation. At the same time, various application phenomena were analyzed reasonably and effectively of petroleum catalytic cracking, the technologies were effective guided to development of inferior heavy oil catalytic pyrolysis quickly-gasification coupling technique and direct crude grading millisecond catalytic pyrolysis gas phase chemical technology, according to the reaction mechanism of initial free radical generation, secondary free radical regulation and free radical compound. It can provide the direction and basis for process condition optimization, reaction regulation and strengthening, catalyst development and optimization and reaction equipment technology development and strengthening by the reaction mechanism of free radical regulation.