Heat transfer enhancement is an effective way to achieve low-carbon development and enhance competitiveness of refinery and petrochemical enterprises. Based on the rich engineering knowledge and refining design experience, the engineering heat transfer enhancement strategy is divided into three steps by systematical classification: equipment, process and whole plant. The equipment enhancement strategy for special processes is recommended by combining application of shell-and-tube heat exchangers. The process enhancement strategy is generalized by analysis of the thermal/cold energy utilization in process of aromatics, crude oil distillation, ethylene, etc. The whole plant enhancement strategy includes the use of low-temperature heat resources, stair-step utilization of steam system and cascade utilization of recycled water systems. These strategies were successfully applied to Hainan and Qingdao Refinery and helped to reduce the energy consumption. It is expected from the study in this paper to strengthen the development of the heat transfer engineering strategy and enrich connotation of the heat transfer enhancement in petrochemical process.

Biomass supply chain is the basic guarantee of the conversion of bioresource, and is also the key to the large-scale utilization of bioenergy in the future. In this paper, related technical problems were firstly analyzed, and the status and existing problems of biomass raw materials harvest and collection, storage and pretreatment and transportation were introduced, respectively. Meanwhile, the tech-economic of the supply chain of biomass was summarized, and the research methods adopted in China and abroad were compared and expounded. The main research areas are to optimize the technical and economic indicators of the supply chain by developing quantitative mathematical models. The research results showed that the purchasing price, collection radius and collective mode of biomass were the key factors influencing the cost of the biomass supply chain. In China, the biomass supply chain is a complex system because of the small sizes of household cultivated land and the dispersal of biomass. On the basis, the prospect of the development of the biomass supply chain was proposed, which can provide a reference for the research and development of the biomass supply chain.

Stimulated emission depletion super-resolution microscopy(STED) can overcome the limit of optical diffraction to achieve the ultra-fine imaging of nanoscale of targets. The fluorescent probes play great roles in this technique. In this paper, the basic concept of STED microscopy was introduced, including the basic optical concept, principle of STED microscopy and imaging system, and STED fluorescent probes and the biological applications were summarized. This paper would be beneficial to the researchers from the fields of chemistry and chemical engineering in understanding of fundamental theory of superresolution imaging microscopy, which is helpful for the design of effective fluorescent probes in STED superresolution imaging. This review also provided the new requirement for fluorescent probes in biomedical imaging area, and the new opportunity for the joint disciplines in chemistry and chemical engineering with optical imaging.

In the industrial processes, rising behavior of bubbles in the liquid and mass transfer on the gas-liquid interface are very common. In this paper, experimental methods and numerical simulation methods are summarized under different conditions. In terms of experiments and numerical simulations, impact factors of single bubble rising behavior, phenomenon and mechanism of coalescence and break up for multiple bubbles, bubble flow pattern and properties in industrial devices, and mass transfer model, especially for gas-interface mass transfer model, are summed up. The results show that the studies about single bubble behavior are sufficient while for the multiple bubbles, more works need to be done. Besides, it is challenging to establish gas-interface mass transfer model due to the limit of research tools. According to the relative research progress and problems, the following suggestions about the future research directions conducting controllability study of coalescence and break up for bubbles, and strengthening of research on gas-interface mass transfer including the research of visualization of the internal flow and convective mass transfer in bubbles.

In order to explore the effect of wall wettability on the flow boiling instability of refrigerant R141b， a microchannel flow boiling experimental platform was designed and three rectangular channels of different wetting properties were fabricated with wall contact angles of 62.3°, close to 0°, and 158.7°, respectively. Using R141b as an experimental working fluids, flow boiling heat transfer experiments were carried out in a rectangular microchannel with a cross-section width × height of 1mm×2mm. The pressure fluctuations at the measuring points along the channel and the factors affecting the fluctuation of the total pressure drop between the inlet and outlet were studied. Finally, the Hurst index analysis of the total pressure drop fluctuation signal were carried out. The results showed that the position with the largest fluctuation variance in the measurement point along the microchannel is near the onset of nucleate boiling (ONB). The decrease of heat flux and the increase of mass flux will delay the onset of nucleate boiling. The fluctuation of total pressure drop at inlet and outlet is influenced by the heat flux, mass flux, and wall wettability. Under the same conditions, the increase of heat flux and the decrease of mass flux will cause the increase of system instability. The total pressure drop fluctuation variance on the superhydrophobic surface of microchannels is larger than that of the other two surfaces, which is 1.35 to 1.84 times larger than that of the superhydrophilic surface with the smallest fluctuation variance. Hurst exponent analysis shows that the system has a chaotic phenomenon, and the Hurst exponent of the super hydrophobic surface microchannel is the largest, showing a more intense instability.

Considering the non-counterflow effect on the heat transfer temperature difference, shell number and area of the heat exchanger, the heat exchanger network system involving the non-counterflow heat exchange is optimized. Based on the stage-wise superstructure with non-isothermal mixing and the comprehensive evaluation index of energy, economic and environmental (3E), a multi-objective mixed integer nonlinear programming (MO-MINLP) model for heat exchanger network optimization is established by introducing the correction factor of temperature difference. Systematic solution strategy and method based on non-dominated sorting genetic algorithm (NSGA-II) are proposed. A case study shows that the optimal design results of heat exchanger networks involving non-counterflow heat transfer are very different from those based on pure counterflow heat transfer hypothesis. The optimal solution can not be obtained only by modifying the design results based on pure counterflow heat transfer hypothesis. In order to ensure the optimization, reliability and practicability of the design results, the effect of temperature difference correction must be taken into account in the modeling. 3E evaluation reflects the trade-offs and constraints between energy consumption, economic benefit, and environmental impact of the heat exchanger network system, and makes the design of the system more practical. At the same time, the multi-objective optimization method can not only get the most economical results as the single-objective economic optimization, but also provide a variety of optimization solutions for choice, improve the flexibility of design, and can meet different design needs.

Computer simulation and experimental study were carried out on the evolution of droplet size distribution during spray drying of mannitol dissolved in water. The shrink rate of the diameter of a droplet during spray drying was treated as a negative growth rate in the population balance (PB) model which was obtained using the reaction engineering approach (REA).The integration of PB and REA yielded the PBREA model, which was solved using a high-resolution numerical method. The drying time of droplets of varied sizes, the change of the mean moisture content of droplets and the droplet size distribution were simulated under different spray drying conditions. The results showed that the drying time increased with the increase of droplet diameter. The ratio of the predicted and measured particle mean diameters was between 1.0 to 1.5, and the span was from 0.61 to 0.89. The errors were analyzed and attributed to three main factors: error due to the statistical analysis of droplet and particle sizes, the difference in drying a single static droplet and a group of droplets in motion, and the empirical thermal conductivity and diffusion coefficient values. Images were collected and analyzed to obtain droplet and particle size distributions with the Buchi 290 spray dryer. The simulated and experimental results showed that the PBREA model could effectively predict the mean diameter and span of particles during spray drying process.

Accurately detecting the oil-water interface and the liquid level in a crude oil tank is very important for petrochemical process system engineering related to the accuracy of the net oil moisture control and that of combination station check system metering. In order to solve the problems that the conventional classification algorithm needs to select typical values manually and the traditional K-means clustering algorithm also needs to select initial clustering centers manually, and the results might not be accurate and stable, this paper proposed an adaptive threshold algorithm for oil-water interface detection, which is based on improved K-means clustering optimization algorithm. The proposed algorithm can calculate the best typical values automatically, and improves the conventional classification algorithm and the traditional K-means clustering algorithm. The proposed algorithm works as follows: first, find the typical values automatically by using an adaptive threshold searching algorithm, then search the optimal points by using the improved K-means clustering optimization algorithm, and finally calculate the oil-water interface and the liquid level according to the optimal partition. Experimental results showed that, compared with the conventional classification algorithm and the traditional K-means clustering calculation algorithm, the proposed adaptive threshold clustering algorithm does not need artificial selection, and can guarantee the results to be correct. Moreover, the number of iterations and running time needed by our proposed algorithm are smaller than those by the traditional and other improved K-means clustering calculation algorithms.

Ceramic tube supported zirconium dioxide dynamic membrane was applied to the separation of oil-in-water emulsion by crossflow microfiltration. Effects of four industrial emulsifiers, i.e., span 80 (SP-80), sodium dodecyl sulfate (SDS), sodium dodecyl sulfate (SLS) and sodium dodecyl benzene sulfonate (SDBS) were investigated. The influence of emulsifier type and concentration, emulsion temperature and flow rate and operating pressure on the process were investigated by orthogonal experiment. The results show that the maximum steady permeate flux exists under operating conditions of SDS, 1.0g/L, 50?C, 120L/h and 0.14MPa. Single factor experimental results show that the steady permeation flux decreases with the increase of emulsifier concentration, and increases first and then decreases with the increase of emulsion temperature. Inorganic salt ions, Na⁺, Ca²⁺ and Al³⁺ can cause a stability loss of emulsion. As the Al³⁺ is more than 0.75g/L, the stability of the emulsion is completely destroyed, which was more beneficial to improving the permeability flux. Based on the experimental results, molecular simulation method was adopted to study the emulsification under experimental operating conditions. Relationship between oil-water interface formation energy (E) of SDS and water interface diffusion coefficient (D) with emulsifier concentration and emulsion temperature was analyzed. Simulation results show that the absolute values of the E and D gradually increase with the increase of concentration and temperature. The experimental and numerical results show that the emulsifying effect of the emulsifier determines the average oil drop size within an emulsion and affects the stable permeation flux according to the plugging mechanism in the separation of oil-in-water emulsion. The simulation results have successfully explained the experimental permeation phenomena from a microscopic perspective. This fundamental research can provide a basis for industrial application of dynamic membrane treatment of oil-water.

The leakage between high and low pressure fluids in the rotary energy recovery device (RERD) for seawater desalination system, which has direct effect on the energy recovery efficiency of the RERD, mainly occurs in the mating clearances between the rotor and the end plates. This research employed the hydrostatic bearing technology into the self-developed motor-driven RERD by making the hydrostatic bearing groove and the damping hole on the flat end plate and creating the hydrostatic bearing end plates to reduce the leakage and improve the efficiency of RERD. The RERD with flat end plates and the RERD with hydrostatic bearing end plates were experimentally compared under the total mating clearance of 0.04mm and rotating speed of 500r/min. The results showed that under the testing conditions of operating pressure of 4.5MPa and capacity of 13m³/h, the leakage of the RERD with 1^# hydrostatic bearing end plates (groove width of 2.0mm) could decrease from 0.45m³/h to 0.28m³/h and the energy recovery efficiency could increase from 91.3% to 92.7% when compared with the RERD with flat end plates. The RERD with 2^# hydrostatic bearing end plates (groove width of 3.0mm) was tested under the same operating condition. The leakage was lowered to 0.11m³/h and the efficiency was improved to 95.0%. The research above indicates the significant effect of the hydrostatic bearing technology in reducing the leakage and improving the efficiency of the RERD, and has important guiding significance for the design and optimization of seal structure of the RERD.

Serious accidents will be caused by the leakage of supercritical CO₂ pipelines. Leakage experiments on small leakage diameters for pure supercritical CO₂ and CO₂ pipeline containing impurities were performed with a small scale (14.85m long, 15mm id) laboratory apparatus. The pressure and temperature responses and the characteristics of phase transitions during the leakage were studied with various leakage diameters and initial inner pressures. The results show that the temperature inside the pipeline reached a minima during the leakage of supercritical CO₂ pipeline and the CO₂ fluid transferred directly from the supercritical state to the gaseous state. Besides, the leakage time and the minimum temperature of the medium in the pipe decreased with the increasing of leakage sizes. The addition of N₂ shortened the whole leakage time and also increased the minimum temperature. The higher N₂ added, the higher the minimum temperature was. Furthermore, based on the self-preservation of leakage time for supercritical CO₂ pipeline, empirical formulas for the pressure responses inside the pipeline were obtainedunder different leakage nozzle diameters and initial inner pressures.under different leakage nozzle diameters and initial inner pressures.

The existence of lithium bromide can significantly improve the process of generation and reduce energy consumption of rectification. But it has negative effect on the absorption process of ammonia. Therefore, the new cycle of NH₃-H₂O-LiBr absorption refrigeration system based on membrane separator was proposed to separate lithium bromide from the solution stream entering absorber and improve absorption performance. And the experiment for separating lithium bromide in the membrane separator was carried out. The results showed that the separation efficiency of lithium bromide can reach 98% after twice solution cycle in membrane separator. Based on the separation efficiency of experiments, the Aspen Plus monitor process was used for further simulating and analyzing the NH₃-H₂O-LiBr absorption refrigeration system with membrane separator. Simulation results indicated that due to the application of membrane separator, the energy consumption of new cycle based on membrane separator was lower than the normal absorption system and the COP can be improved nearly 10%. When generator temperature increased from 60℃ to 120℃, the generator heat load decreased and the COP of absorption cycle increased with the highest value of 0.5869 at the mass fraction of lithium bromide ranging from 0—30%.

By changing the layout of spoiler plates of the solar-air collector with serpentine flow channel, a spiral solar air collector was developed with numerical and experimental studying. The results showed that under the conditions of the average solar irradiance, temperature and flow rate being 819.7W/m², 7.33℃ and 0.025kg/s respectively, the heat-collecting efficiency of the solar air collector could reach 59.14%, which was 2.18% higher than that of the serpentine solar air collector. The pressure loss for spiral one was only 37.26% of the pressure for serpentine solar collector, and the pressure loss decreased significantly with the increase of flow rate. The heat loss coefficient of the spiral solar air collector was in the range of 4.6－5.6W/(m²·K) and the heat transfer factor was between 0.64－0.72 in the temperature range of 30—90℃. The average value of the two was 0.06W/(m²·K) or 0.019 respectively higher than those of the snake solar air collector. Compared with serpentine solar air collector, the spiral solar-air collector increases the heat collection efficiency of the solar air collector and greatly reduces the pressure loss.

An elastic rod was vertically implemented on the bottom of the soft-elastic reactor. The mixing efficiency of the reactor was enhanced due to the motion of the elastic rod. The mixing process and the mixing time were investigated by a discoloration method based on a fast acid-base reaction and the image analysis method. The enhancing effect was quantitatively evaluated by the mixing time. The effects of the position of the elastic rod, the height of the elastic rod, the maximum-penetration depths and the penetration frequency were studied respectively. Results showed that after the elastic rod was introduced, the structure of the isolated region was changed and the mixing time was reduced. When the elastic rod was close to the impacting probe, the mixing enhancement was more obvious. When the height of the elastic rod was below the liquid level, the enhancing effect increased with increasing elastic rod height. When the height of the elastic rod was greater than the liquid level, the enhancing effect was not further improved with further increase of the elastic rod height. Choosing the best condition of the rod position (closest to the impacting probe) and the best condition of the height (just over the liquid level) with the maximum-penetration depth of 2.5cm, the mixing time was reduced by 57% compared with that without the elastic rod. In the experiments preformed, so far, increasing maximum-penetration depth is always beneficial to an increased efficiency.

In this study, a method of using entropy to analyze the reversibility of internal thermal coupling column was proposed. Taking the ethanol water system as an example, it was proved that the energy saving of the thermal coupling column was superior to the traditional column, and the optimum operating range of the column was determined. Based on the second law of thermodynamics, the thermodynamic efficiency and the entropy increase formula of the thermal coupled column were deduced. Firstly, it was proved theoretically that the thermal coupling column was superior to the traditional column in terms of energy saving, and it was also calculated separately by the experimental data. The results showed that the operable compression ratio of the column was initially reduced to 1.8—2.6 in order to achieve better heat transfer between two columns, and the energy consumption of the overhead column was the smallest when the compression ratio was at 2.2. However, the thermal efficiency of the whole column was the highest when the range of compression ratio was 2.2—2.5. When the compression ratio is 2.5, the entropy increase of the whole column was also better than the average of the entire operating range. Thus, it was considered that the thermal coupling column had higher reversibility and better energy saving effect in this range. Taking the energy consumption, thermodynamic efficiency and entropy increase and other parameters into account, the compression ratio of 2.2 to 2.5 was the best operating range of the column.

The sodium content of Zhundong coal is high and the boiler will face severe slagging problems during the combustion. Synthetic coals were obtained by adding ash model compounds to ultrapure coal which was obtained from the Zhundong coal. And the effects of Na₂O on the combustion performance and ash fusion characteristics of coal were studied by using thermogravimetric-differential scanning calorimetry (TG/DTG/DSC), X-ray diffraction (XRD) and ash fusion temperature test. The results showed that: sodium mainly affected the ignition temperature (T_i) and the stage of char combustion of the synthetic coal. The increasing of sodium would rise the T_i. When the mass fraction of Na₂O increased from 5% to 8%, the rate of char combustion decreased first and then accelerated. Sodium could improve the burnout characteristics of coal and would decrease ash fusion temperature which was more obviously when Na₂O>5%. The fluxing effect of sodium to mullite in the ternary phase diagram was the important reason of the decreasing ash fusion temperature. XRD analysis showed that quartz, which acts as a framework in ash, can react with refractory minerals (such as xonotlite and MgO) to generate low-melting feldspar minerals under the fluxing action of sodium. These feldspar minerals would promote ash melting under high temperature and decrease ash fusion temperature. At the same time, the generated nepheline could intensify ash fusion.

Organic Rankine cycle (ORC) system has been widely used in industries due toits superior performance. The working fluid pump, providing the mass flow rate and the evaporation pressure of the ORC system, is one of important components in the system. In addition, the performance of working fluid pumps also has significant effects on the component and overall system performance. In this paper, the effects of different thermal parameters on the pump electric power input of unit mass flow and back work ratio (BWR) were analyzed. Furthermore, the experiment was conducted under simulative ORC conditions by using R245fa and condensing temperature of 303K. The experimental operating characteristics of two different types of working fluid pumps (multistage centrifugal pump and hydraulic diaphragm metering pump) were analyzed and its effects on the performance of ORC system were presented. Results showed that the mass flow rate delivered by the hydraulic diaphragm metering pump was low and was not significantly affected by the variation of outlet pressure. The maximum electric power input was only 360.34W, which was 16.29% of the multistage centrifugal pump. Their actual operation efficiency changes with operating conditions were up to 59.96% and 55.26%, respectively. By the theoretical calculation, the BWR for the ORC system using the two pumps varied between 0.03 and 0.48. And the maximum thermal efficiency could reach up to 11.66%, 10.35%, respectively. The hydraulic diaphragm metering pump is more suitable to the low mass flow ORC system.

To improve the characteristics of the bio-oil, La modified HZSM-5 with hierarchical structure was applied in the catalytic pyrolysis of biomass. First, the HZSM-5 zeolite was pretreated with Na₂CO₃ solution, and then the pretreated HZSM-5 was modified with different loadings of La by impregnation. The modified HZSM-5 were characterized by XRD, BET, SEM-EDS and Py-IR, respectively. The catalysts were used in the process of preparing bio-oil and the bio-oil organic phases were studied from the aspects of composition and physical properties. The results showed that the modified HZSM-5 catalysts formed micro/meso-porous pore structure and retained typical MFI topology structure. But the modification of La changed the acid distribution of the zeolite. With the increase of loadings of La, the yield, density, kinematic viscosity and oxygen content of bio-oil organic phase decreased first and then increased, while the content of oxygenated compounds and carbonyl compounds showed the same tendency as well. The hierarchical porous HZSM-5(La loading were 5%) catalyst had a better effect on the removal of aldehyde and ketone contained in the bio-oil organic phase which improved the stability of the bio-oil, the oxygenated compounds and the carbonyl compounds decreased by 32.43% and 57.03%, respectively. Meanwhile, the hydrocarbon content and the higher heating value of the bio-oil organic phase reached 49.86% and 37.7MJ/Kg, respectively.

Hydrodesulfurization(HDS) is an important process in producing clean fuel. MoS₂-based catalysts are the major catalysts in HDS, therefore a thorough understanding of the active phase structure and HDS mechanism is useful for the development of new catalysts. This paper reviewed the active phase structure of MoS₂-based catalysts， including the effects of sulfiding conditions, promoter atoms and support type. And a general overview of the challenges of characterization on the active phase structure of MoS₂-based catalysts was provided. The microstructure characteristics of the active phase under different conditions were summarized. Meanwhile, the catalytic mechanism of thiophene HDS was analyzed based on the composition and structure of MoS₂-based catalysts, and the results indicated that the HDS activity was closely related to the catalyst’s microstructure. Finally, the important role of theoretical calculation in the development and design of efficient hydrodesulfurization catalysts was outlined.

The efficient utilization of huge amount of hydrogen chloride byproduct is in urgent need for chlorine-based chemical industry. Heterogeneous catalytic oxidation of HCl (so-called Deacon process) to recycle chlorine, is regarded as a low energy-consuming and sustainable route. The design and fabrication of the oxidation catalyst are significant to the process. The catalytic reactivity, stability and catalysis mechanisms of Cu-based, Ru-based and Ce-based catalysts are reviewed in this paper. Cu-based catalyst mainly obeys the Mars-van Krevelen mechanism in Deacon process, while Ru-based and Ce-based catalysts follow the Langmuir-Hinshelwood mechanism. The latter two exhibit better catalytic reactivity and stability. As the reaction is exothermic, reducing reaction temperature is the key to improve the HCl conversion. In addition, the dispersibility deterioration of active component by sintering is one of the main causes of the deactivation for Ru-based and Ce-based catalysts. The development of composite oxide catalysts with high low-temperature reactivity and stability is indicated as one of the main research work in the future .

A series of Pd/Al₂O₃-CuO catalysts with different CuO contents were prepared by impregnation method. The catalysts were then used in the ethanol oxidation reaction and their structures and properties were investigated by using XRD, H₂-TPR and NH₃-TPD techniques. The results showed that the reactivity was not always enhanced with the increase of CuO contents. The Pd-1.0%CuO/Al₂O₃ catalyst showed the best performance whose T ₅₀ and T ₉₀ decreased more than 50℃ in comparison with Pd/Al₂O₃. Compared to Pd/Al₂O₃ catalyst, catalysts with CuO showed an enhancement in diffraction peak intensity but no decomposition of palladium hydride, indicating that the Pd-Cu alloy structure was formed leading to the synergistic effect between Pd and Cu species. For Pd-1.0%CuO/Al₂O₃, the shift of reduction peak to low temperatures and the increase in area demonstrated the reduction of the oxidizing substances on the catalyst and the amount of them was increased which was beneficial to the oxidation reaction. The new reduction peak illustrated that the interaction between Pd and Cu had produced some new species. NH₃-TPD results showed the high content of low temperature acid was conducive to the high reactivity and the new desorption peak indicated that new acidic sites were formed on the Pd-1.0%CuO/Al₂O₃ catalyst.

The composite photocatalysts Ag₃PO₄ coated with AgI were prepared via solid state grinding method. Through being grinded in a mortar, Ag₃PO₄ reacted with KI under the mechanochemical effect. The AgI nanoparticles, which were obtained by the solid-state reaction, was coated on the surface of the Ag₃PO₄ particles. The compositions and morphologies of the AgI/Ag₃PO₄ composite photocatalysts could be controlled by adjusting the KI content and the grinding time. The AgI/Ag₃PO₄ composite photocatalysts exhibited strong absorption to the visible light, and much higher photocatalytic activity than that of single Ag₃PO₄ or AgI. As a result, the as-prepared photocatalysts exhibited the highest photocatalytic activity, when the KI content of 10% and the grinding time of 10 minute was adopted. The degradation efficiency of Rhodamine B could reach 99% under visible light irradiation for 1h. The AgI/Ag₃PO₄ composite photocatalysts had excellent stability and recyclability. The AgI shells avoided the photocorrosion and improved the structural stability of Ag₃PO₄ in water. The valence band and conduction band potentials of AgI were both more negative than that of Ag₃PO₄. Therefore, the photoinduced electrons of AgI could be transferred to the surface of Ag₃PO₄, and the photogenerated holes of Ag₃PO₄ could migrate to the valence band of AgI. So, the probability of the electron-hole recombination was decreased, and the photocatalytic activity was enhanced.

The solid residues after pyrolysis of pure urea and urea/TiO₂ at different temperatures were collected and analyzed by using infrared spectroscopy(IR) and gas chromatography mass spectrum(GC-MS). Thermogravimetric-infrared(TG-FTIR) technique was used to analyze the pyrolysis characteristics of urea and cyanuric acid and the transformation mechanism of gaseous compounds in the pyrolysis process with and without TiO₂. The kinetic equations and parameters were obtained from the for non-isothermal weight loss curves according to the Coats-Redfern method. The results showed that urea and biuret were the main pyrolytic residues of urea at 100—250℃, while the nitrogenous heterocyclic organic compounds such as cyanuric acid were the main pyrolytic residues of urea at 300—400℃. Anatase TiO₂ can promote the pyrolysis reaction of urea and cyanuric acid and thus shorten the reaction process, since HNCO and water vapor can react easily on the surface of TiO₂. The reaction order of urea for the pyrolysis alone in the first stage of pyrolysis is 2, the activation energy is 113.25kJ/mol, and the pre-exponential factor A is 2.01×10¹¹min^-1. Under the presence of TiO₂, the activation energy E is 77.42kJ/mol, and the pre-exponential factor A becomes 4.82×10⁷min^-1.

1,1-Diphenyl-1-[(2S,4R)-4-(4-vinyl-benzyloxy)-pyrrolidin-2-yl]-methanol (monomer4), styrene and polyether Pluronic F-127 were initiated by lauroyl peroxide for solution polymerization, to obtain a unique comb graft-copolymer, which was further reacted to form the gel crosslinked CBS catalyst precursor (G-CBSP). The novel CBS gel catalyst (G-CBS) was then prepared by condensation reaction of the G-CBSP with methylboronic acid in toluene-tetrahydrofuran and subsequently used for the asymmetric reduction of acetophenone. The structure of the catalyst was characterized by FTIR. The influence of the polyether Pluronic F-127 component on the gel morphology of the catalyst was observed by SEM. Besides, the catalytic performance and the recyclability of catalyst were investigated. The G-CBS catalyst was compared with the polystyrene supported CBS catalyst. The results showed that the introduction of polyether Pluronic F-127 component had a solubilizing effect on G-CBS which enhanced the compatibility between the catalyst and the reaction system, which effectively solved the problem of the selective reduction of the highly crosslinked supported catalyst. With the catalyst, the ee value of the reduced product phenylethanol was 94%, which was close to the performance of homogeneous system and better than the currently reported catalysts in heterogeneous system. After the catalyst was recycled for 5 times, the ee value of phenylethanol can still reach 90%, and the conversion of acetophenone approached 100%.

Carbon doped ZnO thin films with high catalytic activity were prepared on glass surface by magnetron sputtering. The prepared thin films were characterized by X-ray diffractometer, high power transmission electron microscopy and X-ray photoelectron spectroscopy. The photocatalytic properties of the films were tested for the visible-light driven conversion of nitrogen to ammonia. The results show that there are carbon quantum dots in the films with a size of 4nm and an interplanar spacing of 0.21nm that allows the thin films to absorb visible light. At the same time, the carbon atoms in the ZnO lattice may increase the conduction band edge position of the films, so that the reductive potential of the excited electrons is enhanced. When the amount of carbon doping was 1.03%, the ammonia yield was 5.15×10^-4mol/(h·cm²). Sphere segment shaped pits with an opening size of 0.5—2μm and a depth of 100—500nm were made on the glass surface using a reverse micelle solution etching technology. The ammonia yields of the films on the etched glass was about 1.4 times higher than that on the plane glass. Meanwhile, the critical load values for the films on the etched glass were about 2 times higher than those for the ones on the unetched glass. Following that, the photocatalytic mechanism was discussed based on the band structure diagram of the carbon doped ZnO films.

With the recent rapid expand of LiNi _x Co _y Mn _z O₂ battery market, the retired lithium ion batteries will gain explosive growth in the future. Therefore, the recovery of valuable metals such as cobalt, nickel and lithium in the electrode materials of LiNi _x Co _y Mn _z O₂ batteries has become another hot spot in the battery industry. This paper reviews the technological process and main methods for the recovery of the valuable metals from LiNi _x Co _y Mn _z O₂ batteries by wet process, with the focus placed on the leaching methods of valuable metals, separation and extraction of valuable metals, reutilization and leaching kinetics. The advantages and disadvantages of different processing methods are compared. In addition, economic analysis shows that the recovery of valuable metals from retired LiNi _x Co _y Mn _z O₂ batteries has considerable economic value. Finally, the methods for the recovery of the valuable metals of LiNi _x Co _y Mn _z O₂ batteries by wet process are summarized, and the important technologies in the future are briefly described, including chemical purification, automatic disassembling and classified recovery, which provides reference for the future development of recovery of LiNi _x Co _y Mn _z O₂ batteries.

To explore the effect of composite nanoparticles on the flame retardancy of epoxy acrylate (EA) coating, mesoporous silica nanoparticle was synthesized by using cetyltrimethylammonium bromide (CTAB) and tetraethoxysilane (TEOS) as raw materials, and zinc stannate nanoparticle was synthesized based on ZnCl₂ and SnCl₄·5H₂O as raw materials. Then mesoporous silica/zinc stannate nanoparticle complex was prepared by compounding them, and the above nanoparticles were characterized by X-ray powder diffractometer (XRD) and transmission electron microscope(TEM). Three kinds of composite coatings(SiO₂/EA, Zn₂SnO₄/EA, SiO₂/Zn₂SnO₄/EA) were prepared by UV curing method through mixing the above prepared nanoparticles（mesoporous SiO₂, Zn₂SnO₄， SiO₂/Zn₂SnO₄）， acrylic acid, acrylamide with EA, and the transmittance, thermal stability and flame retardancy of the coating were measured by UV-vis spectrometer, differential scanning calorimeter(DSC) and oxygen index tester. The results showed that the comprehensive properties of SiO₂/Zn₂SnO₄/EA coatings were superior. When the mass percent content of SiO₂/Zn₂SnO₄ was 4.85%, the thermal stability and flame retardancy of the coating are the best. The coating’s limiting oxygen index, combustion grade, carbon residue rate (calcined in muffle furnace at 500℃) and hardness were 31，V-0，17.32% and 6H, respectively.

The mathematical models on the three regions, including combustion space, the basalt liquid space and the raw material melting space in the basalt fiber tank, were established based on computational fluent dynamics (CFD). According to the heat fluxes and temperatures at the interfaces between the three regions, a thermal coupling simulation was performed by Fluent software. Meanwhile, the models were verified by comparing with experimental results, and the distribution characteristics of the temperature and velocity fields at these regions were numerically analyzed. The results indicated that the design and parameters of basalt fiber tank could be optimized by the simulation method mentioned above. The temperature of the whole combustion space was uniformly distributed by utilizing the top firing gun, and the temperature around the free surface of molten liquid was maintained at a high level. From the free surface to the bottom of basalt liquid space, the temperature of molten flow was gradually increased and then reduced. Furthermore, the maximum occurred near the horizontal height of the electrodes. The uniformity of temperature could be improved along the depth direction of the tank by utilizing the electric boosting technology. Therefore, the scale of production could be greatly enlarged and the cost be reduced.

Li₄Ti₅O₁₂ and Li₄Ti₅O₁₂/graphene composite have been successfully prepared by a solid-state ball milling and spray drying method using Li₂CO₃, TiO₂ and graphene as starting materials. X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy were used to confirm the structure and morphology of the materials. The effects of the amount of graphene on the electrochemical properties of Li₄Ti₅O₁₂ were investigated by the galvanostatic charge-discharge tests. When 1% graphene was added, the Li₄Ti₅O₁₂/graphene composite (LTO-G-2) exhibited excellent performance with the charge capacities of 172.9mA·h/g, 165.7mA·h/g, 163.5mA·h/g, 157.4mA·h/g, 154.0mA·h/g and 143.5mA·h/g at rates of 0.2C, 0.5C, 1C, 3C, 5C and 10C, respectively. Moreover, LTO-G-2 showed a charge capacity retention of 94.8% after 200 cycles at a rate of 5C. Cyclic voltammetry tests (CV) showed that LTO-G-2 had the smallest polarization. Electrochemical impedance (EIS) tests showed that the charge transfer resistance of LTO-G-2 (69.6Ω) was lower than that of neat LTO (140.5Ω).

The flow-electrode is a suspension system composed of carbon nano-materials, dispersants and deionized water, and its good dispersion and suspension-stability is the key to ensure the high desalination efficiency of the flow-electrode capacitive deionization (FCDI) process. In this paper, the carbon nanotubes (CNT) as the active materials of flow-electrode was modified by sulfonation to improve the materials hydrophilicity, and the specific capacitance, dispersion and suspension stability of flow-electrodes of CNT and CNT-S were investigated. The sodium dodecyl sulfate (SDS) and cetyltrimethyl ammonium bromide (CTAB) were used to examine the effects of dispersants on the performance of flow-electrodes, and the effects of the quality-ratio of dispersants on the performance of flow-electrode were also assessed. The results showed that the CNT-S flow-electrode had a better dispersion and suspension stability than the CNT flow-electrode. In addition, compared with CTAB dispersant, the SDS with identical charge characteristics as CNT-S can enhance the specific capacitance, dispersion and suspension stability of the CNT-S flow-electrode, and the specific capacitance of the CNT-S flow-electrode was 40.04F/g at SDS quality-ratio of 0.6. For the FCDI cell assembled with the CNT-S flow-electrode at 0.6 SDS quality-ratio, the high salt removal efficiency of 51.9% was achieved in 1.0g/L NaCl solution at voltage of 1.2V and the salt removal efficiency of FCDI cell still maintained at 51.6% after 20 regeneration cycles, showing that the CNT-S flow-electrode at 0.6 SDS quality-ratio had excellent recycle stability. These results provided the new evidence to the practical application of FCDI process.

In recent years, supported L-proline and its derivatives are widely used as promising chiral catalysts in asymmetric organic chemical reactions owing to their high selectivity and reusability. This paper briefly introduces the types of L-proline and its derivatives. This paper also illustrates the types of the catalyst support, including ionic liquid, inorganic nanoparticles, organic polymer, ionic liquid-polymer and organic-inorganic hybrid microspheres. Additionally, this paper describes different immobilization methods of L-proline, including click chemistry and RAFT polymerization, together with their advantages and disadvantages and the improvement recommendations. The suggestions and prospects provide useful information for the preparation of novel immobilized catalysts, which have high activity, selectivity and excellent reusability in asymmetric reaction.

Polyvinylpyrrolidon （PVP）-P84 copolyimide（P84） / polyacrylonitrile（PAN） composite membranes were prepared via blending of PVP into P84 matrix. Membranes were characterized by Fourier transform infrared（FTIR），X-ray diffraction（XRD），scanning electron microscopy（SEM），differential scanning calorimeter（DSC） and contact angle（CA） metering. FTIR analysis indicated that PVP and P84 were physically blended. DSC results showed that the P84-PVP blends possessed a single glass-transition temperature， indicating a good miscibility of blend. The contact angle test demonstrated that the hydrophility of membranes was improved with the incorporation of PVP. XRD results indicated that d-spacing in the P84-PVP blend was increased when the PVP loading amount was increased. The effect of PVP loading，operating temperature and feed composition on the pervaporation performance of the composite membranes was examined. When PVP content was enhanced to 20%， the total permeation flux was increased. Meanwhile，the separation factor was first increased with the PVP content≤ 10%，and then decreased quickly. The composite membrane with a PVP loading amount of 10% exhibited the best performance with a total flux of 259g/(m²?h) and a separation factor of 41 using a feed of methanol（30%）/tetrahydrofuran at 20℃.

The MnO₂/PPy composite materials were prepared by miniemulsion method (W/O) with Py and KMnO₄ as raw materials, which obtained spherical floral structure. The impinging stream-rotating packed bed (IS-RPB) was selected as an emulsion equipment to prepare miniemulsion. The concentration of p-toluenesulfonic acid, concentration of potassium permanganate and reaction time on the specific capacitance of MnO₂/PPy composite materials were studied. And the electrochemical performances were investigated also. The results showed that the optimum conditions of synthesis MnO₂/PPy composite materials by miniemulsion polymerization were concentration of p-toluenesulfonic acid of 0.84mol/L, concentration of potassium permanganate of 0.094mol/L and reaction time of 3.5h. Under the suitable operating conditions, the specific surface area of MnO₂/PPy composite materials was 177.1m²/g and the specific capacitance was 231.9F/g at 0.5A/g. The specific capacitance and cycle stability of MnO₂/PPy electrode were enhanced due to synergistic effect between MnO₂ and PPy.

Fe-doped manganese dioxide were synthesized via a simple liquid-phase process in order to improve its potential-window and stability. The phase structure, morphology, and size of the prepared manganese dioxide were characterized by using X-ray diffraction, scanning electron microscopy, and N₂ adsorption-desorption isotherm and the electrochemical properties of the Fe-doped manganese dioxide were investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (PT), cyclic performance test, the high-rate discharge ability and alternating current (AC) impedance spectroscopy. The structure and morphology measurements showed Mn/Fe-2.0 were porous and had good crystal structure. Electrochemical measurements confirmed Mn/Fe-2.0 had the best capacity in neutral electrolytes, and its specific capacitance reached 489F/g, which increased by 22% compared to that of pure manganese dioxide. Therefore, Mn/Fe-2.0 could be an ideal anode material with a wide-potential-window and good cycling stabilities for supercapacitors.

The peapod-like composite phase change microfibers, with both polyvinyal butyral (PVB) matrix blended with aluminum oxide (Al₂O₃) nanoparticles and with n-pentadecane encapsulated, are successfully prepared by microfluidic technology. Effects of Al₂O₃ content on the microstructures, phase change properties and thermal conductive properties of the as-prepared composite phase change microfibers are systematically investigated. The results show that n-pentadecane is effectively encapsulated into the independent micro-compartments by the dense surface of composite phase change microfibers, and the encapsulation ratio is about 30%. The addition of Al₂O₃ nanoparticles into the PVB matrix has no obvious effect on the peapod-like microstructure and phase change enthalpies of composite phase change microfibers, while significantly enhances their thermal conductive properties. Under the simulated solar irradiation, the surface temperature of the composite phase change microfibers containing 10% Al₂O₃ nanoparticles increases faster than that of phase change microfibers without Al₂O₃ nanoparticles, and the melting time of the former are shorten by 25%. The results provide valuable guidances for fabricating phase change microfibers with controllable structure, satisfactory and stability thermal conductive properties, as well as efficient and fast thermal regulation properties.

Titania nanotube arrays(TNAs) were prepared by electrochemical anodization, and the effects of preparation conditions on the surface morphology of TNAs were investigated. The graphene quantum dots titania nanotube arrays (GQDs TNAs) composites were prepared by electrophoresis, and the photocatalytic performance of the composites were investigated using Rhodamine B as a target degradant. Further, the structures and photoelectric characteristics of TNAs and GQDs/TNAs are analyzed by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Raman spectroscopy, UV-vis diffuse reflectance spectroscopy(UV-vis DRS), electrochemical impedance spectroscopy(EIS), and photovoltage test. The results show that the number of oxidation and type of electrolyte have a significant effect on the orderliness of TNAs. The secondary oxidation time, secondary oxidation voltage and NH₄F mass fraction have a significant effect on the tube length and tube diameter of TNAs. The deposition of GQDs under suitable conditions helps to enhance the photocatalytic performance of TNAs. After 120 minutes of visible light irradiation, the degradation rate of Rhodamine B by GQDs/TNAs composites reached 70.3%, which was 19.7% higher than that of TNAs. And the composites have good stability. Photoelectricity tests also showed that the optical absorption efficiency and photoelectron transfer ability of the GQDs/TNAs composites were significantly higher than those of TNAs.

A layer-by-layer method was employed for the synthesis of the HKUST-1 which deposition on functionalized organic surfaces（HKUST-1 SURMOF）. The XRD and SEM techniques were used to investigated the morphologies and structures of the SURMOF, the UV-vis technique was used to investigated the capacity of selective adsorption of dye molecules of type methylene blue （MB） and nuclear fast red （NFR）. It can be assumed that the different adsorption behavior of MB and NFR was caused by the different chemical structure. It might be assumed that the pyridyl moiety of the MB dye strongly adsorbed with HKUST-1 structure， while NFR did not build such interaction. While most of the MB molecules were removed from the mixture， the NFR molecules remained in the solution.

A monolithic macroporous/mesoporous SiO₂ with three-dimensional (3D) continuous pass-through pore structure was prepared by the hard template method. It was the surface functionalized with polydopamine (PDA) by the in situ oxidation polymerization of dopamine in its micro-channels to obtain the macroporous/mesoporous composite PDA/SiO₂. Samples were characterized by SEM，BET，FTIR and TG. PDA/SiO₂ was used to immobilize commercial Novozymes laccase; and the effects of pH，immobilizing time，initial concentration of laccase and temperature on laccase immobilization were investigated. Using azophloxine as a simulated pollutant, the catalytic performance of the immobilized laccase for the degradation of dye was studied. The results showed that the activity of immobilized laccase reached the maximum (348.9U/g) under conditions of initial laccase concentration 80mg/mL，pH of 4.0，immobilizing time of 6h and temperature of 25℃. Up to 99.9% of azophloxine was decolored under azophloxine concentration 10mg/L，pH of 7.0，temperature of 30℃, and degradation time of 8h. The immobilized laccase exhibited good reusability and it can be easily recovered from the reaction system.

Recently, more attentions have been paid to the coupling technologies of biogas slurry treatment based on microalgae cultivation in the field of utilization of biogas slurry. In this paper, both recent progress and future direction of the coupling technologies were summarized. Then, the key areas of the development of coupling technology were also pointed out, such as the high CO₂ tolerance algae breeding and study on the mechanism of carbon sequestration in coupling technology of biogas slurry treatment and CO₂ fixation, low cost and low energy consumption technology development of high-quality biomass production in coupling technology of biogas slurry treatment and high-quality biomass production, systematic evaluation system lacking in coupling technology of biogas slurry treatment and ecological agriculture. Finally, the prospects were reviewed from four points to promote coupling technologies to break through the existing bottlenecks, which are microalgae breeding, microalgae cultivation, biogas slurry treatment, and comprehensive economy of biogas engineering.

To improve the thermostability of family GH11 xylanase MxynB from Aspergillus niger NL-1, a disulfide bridge (Cys¹¹⁶-Cys¹³⁵) was introduced into the corresponding region of MxynB by site-directed mutagenesis. Then, xylanases MxynB and MxynB-116-135 were fused with the thermophilic cellulose binding domain (CBD) from Thermotoga thermarum DSM5069 at N-terminal of xylanases using PCR. The wild-type enzyme MxynB and the mutated enzymes MxynB-116-135, CBD-MxynB and CBD-MxynB-116-135 were expressed in Escherichia coli BL21(DE3), separately. After purification, their enzymatic properties were analyzed and compared. The optimal temperature of the recombinant MxynB-116-135 was 50℃, which was 5℃ higher than that of MxynB. Moreover, the thermostabilities of two recombinant mutants CBD-MxynB and CBD-MxynB-116-135 were clearly increased as compared with the wild-type enzyme under 70℃. Between them, CBD-MxynB-116-135 increased notably. After 2h, the relative activity of the mutant CBD-MxynB-116-135 was over 50%, and the wild-type MxynB was basically inactivated. All the results indicated that the introduction of a disulfide bridge and cellulose binding domain (CBD) could improve the thermostability of the MxynB notably. In addition, 2.5mg/mL corncob xylan was treated with 40U/g mutant xylanase CBD-MxynB-116-135 for hydrolysis. After 10h, the xylooligosaccharides yield was 39.6%, and the content of XOS_2-3 reached 87.9%. All these results indicated that this mutant xylanase could be suitable for potential applications in the xylobiose and xylotriose production.

To enhance the resistance of Saccharomyces boulardii （S.boulardii） to the environment, its microcapsule was prepared by compound wall materials. Based on the application of modified starches, β-cyclodextrin and gelatin as compound wall materials, the effect of the ratio of three blended wall materials was assayed on colony-forming units in S. boulardii microcapsules using the orthogonal experimental method. Then an optimization was performed concerning several spray drying processing parameters, such as compound wall material concentration, inlet temperature, air flow, and feeding speed via the single factor process and the orthogonal test. Further, corresponding morphology and tolerance to artificial digestive juice were observed. The results showed that the optimal ratio of modified starches, β-cyclodextrin and gelatin was 6∶3∶5 with the 10% concentration of S. boulardii. The optimal spray drying processing parameters were as follows: the compound wall material concentration of 16%, inlet temperature of 80℃, air flow of 550L/h, and feeding speed of 15mL/min. Besides, the leading influence factor on the production of S. boulardii microcapsules was inlet temperature, followed by compound wall material concentration and feeding speed, and finally air flow. Under those conditions, S. boulardii microcapsules were spherical without holes and cracks on the surface, and with an average size of 138.65μm. Moreover, S. boulardii microcapsules were also found to be good tolerance to artificial digestive juice, as well as slow-release in simulated gastrointestinal conditions. Collectively, the present study lays a foundation for the commercial production of S. boulardii microcapsules.

Alkali/surfactant/polymer (ASP) flooding technology has been used successfully in the Daqing oilfield, but the water produced from ASP flooding is difficult to treat due to the existence of oil displacement agents, which restricts the promotion of ASP flooding technology. The simulated ASP flooding produced water was prepared in the lab; then the effect of displacement agent on oil droplets stability was studied by settling experiment; the effect of oil displacement agent on oil-water interfacial tension, Zeta potential and oil droplet size explained the mechanism of the oil displacement agent on the stability of the oil droplet. The simulation experiment results showed that the stability of oil droplets increased first and then decreased with increasing NaOH concentration. When the NaOH concentration was increased from 0 to 400mg/L, NaOH reacted with acidic substances in the crude oil to form surfactant that enhanced the stability of the oil droplets. When the concentration of NaOH was greater than 400mg/L, NaOH itself acted as an electrolyte to compress the double layer, reducing the stability of the oil droplets. The stability of the oil droplets increased with the increase of the surfactant concentration, due to the surfactant absorbed on the surface of oil droplets, which could reduce the interfacial tension and increase the Zeta potential of oil droplets, so that the stability of oil droplets increased. The stability of oil droplets first decreased and then increased with the increase of polymer concentration. When the concentration of the polymer is less than 300mg/L, the bridging and flocculation of the polymer plays a leading role. The polymer molecules can absorb on the surface of the oil droplets and link the oil droplets together. At the same time, the polymer can compress the double layer of the surface of the droplet, which is beneficial to the coalescence of the oil droplets. The viscosity of the system increases and the movement speed of the oil droplets decreases when the concentration of the polymer is greater than 300mg/L. At the same time, the polymer molecules occupy the surface of the oil droplets, showing the steric hindrance, which makes the stability of the oil droplets increase and is not conducive to the coalescence of oil drops.

Palmitoyl methionine surfactant (PMS) was synthesized using natural palmitic acid and methionine by acyl chloride reaction and amidation reaction. The effect of reaction temperature, molar ratio of reactants, reaction medium volume ratio, and reaction time on the amidation reaction was investigated by single factor experiment method. In addition, the structure of the product was characterized by FTIR、¹H NMR and mass spectra, and the surface properties of the product and the properties of the complex system were determined. The results showed that the optimal conditions of amidation reaction were screened out as follows: reaction temperature of 30℃, the molar ratio of reactants 1∶1.2, the volume ratio of reaction medium 1∶2, and the optimum reaction time 2.5h. Under the above conditions, the product yield was 89.0%. And the result of the characterization is the target product. Furthermore, the critical micelle concentration (CMC) and surface tension of product were 1.2×10^-4mol/L and 29.59mN/m, respectively. The emulsification of the product with many organic solvents was clearly superior to lauroyl glutamic acid surfactant(LAS). When the molar ratio of PMS and coconut oil propyl betaine surfactant (CPBS) was 4∶6, the surface properties of the complex system was the best. Under those conditions, the CMC and surface tension of the complex system were 9.5×10^-5mol/L and 28.1mN/m, respectively.

Bayberry tannin grafted bovine serum albumin nanaopheres (BSA-BT-NSs) were prepared using the desolvent method, and the removal performances of Pb²⁺ onto BSA-BT-NSs were investigated systematically under different removal conditions, including pH, adsorbent dose, contact time, and initial Pb²⁺ concentration. The results showed that BSA-BT-NSs dispersed uniformly having a good spherical structure grafting with 50% of bayberry tannin (based on the amount of BSA-NSs). The maximum adsorption capacity of BSA-BT-NSs for Pb²⁺ reached up to 76mg/g using 0.4g/L of adsorbent dosage to treat the Pb²⁺ containing solution with the initial concentration of 250mg/L at pH 5.0 and 298K for 20min．The adsorption processes of Pb²⁺ onto BSA-BT-NSs were well-fitted to Langmuir model and pseudo-secondary adsorption kinetics model, indicating a single layer chemical adsorption. A desorption efficiency of 92.04% was obtained using 0.1mol/L nitric acid as eluent to carry out the desorption experiments of Pb²⁺ on BSA-BT-NSs, which could be reused. Furthermore, nitrogen on amino, oxygen on hydroxyl and carboxyl of BSA-BT-NSs were involved as electron donors to form coordination complexes with the empty orbital of Pb²⁺.

Phosphine is widely produced from paddy cultivation, refuse landfill, wastewater treatment, industrial production or other sources. However the formation mechanism and transformation pathway of phosphine in the environment are still unclear. Based on the environmental benefits of phosphine, this review investigated the release and spatiotemporal distribution of two kinds of phosphine, free gaseous PH₃ and matrix-bound PH₃, and analyzed the transformation pathways including catalytic conversion, photochemical oxidation, microbial degradation and so on, then explored the mechanism for PH₃ conversion and analyzed some significant problems related to the biogeochemical cycling of phosphine. According to the obtained research on source and sink analysis as well as phosphine’s transport and transformation in environment, follow-up research can focus on the following three aspects: ① the formation mechanism and process intensification of gaseous phosphine in the anaerobic wastewater treatment system; ② the response relationship between water eutrophication and phosphine and its oxidation products; ③ the mechanism and specific pathway of phosphine bio-oxidation system.

In recent years, the nitrogen removal from water and wastewater with microbial fuel cell (MFC) has received more and more attention because of the nitrogen removal accompanied with the part recovery of energy, which overcomes the defect of high energy consumption in conventional biological nutrient removal. Based on the technology of microbial denitrification and relevant research literatures, this paper reviewed latest research progress and current situation of nitrogen removal with MFC. Four different forms of MFC in nitrogen-containing water and wastewater treatment were summarized, including denitrification-MFC, nitrification-MFC, simultaneous nitrification and denitrification-MFC and anammox-MFC. The performance of power out and nitrogen removal and applicable conditions were described in detail. In addition, the mechanism and influence factors (such as operating conditions, external resistance, electrode materials and configuration of MFC) of nitrogen removal and electricity production were analyzed. At last, it was pointed out the main research direction for nitrogen removal with MFC in the future as follows：developing new cost-effective electrocatalytic electrode materials and membrane materials, optimizing operation conditions and improving the stability of electricity generation biofilms to expand the scale of operation.

Mercury in natural gas may bring harm to the development and use of natural gas. The fixed bed adsorption method was used to remove mercury from natural gas. Mercury removal adsorbents were prepared by using Al₂O₃ and activated carbon composite particles as carriers, and carrying S、CuS and CuS _x as active substances were carried by dipping method. The influence of the preparation process conditions was investigated. The active components were characterized by X ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that CuS and S were successfully loaded on the carrier, of which the mass fraction of CuS was 12.80% and the total mass fraction of S was 8.32%. Effects of mercury content at the inlet and residence time on mercury removal of adsorbent were investigated. The mercury content of natural gas at outlet is 24.99μg/m³, which meets the requirement of industrial natural gas, with 300μg/m³ mercury content of treated natural gas at intet and the residence time 1s. When the residence time is 2s and the mercury content of the intake reaches 600μg/m³, the mercury content of outlet is 18.92μg/m³, less 28μg/m³. The mercury capacity of mercury removal adsorbents is 6.36%.

Tea waste/nano-Fe₃O₄ magnetic composited adsorbent(MTW) was prepared by co-precipitation approach and characterized by scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared(FTIR), X-ray diffraction(XRD), and surface area measurement. The adsorption properties of the methylene blue(MB) from aqueous solution onto the MTW was also studied. The results showed that the MTW was successfully synthesized, which provided a good magnetic response. The surface of MTW was full of particulate matter deposited and showed a rough morphology. The adsorption capacity of MB onto MTW increased first then decreased with the increment in nano Fe₃O₄ content, and reached the maximum with 23.12wt% of nano Fe₃O₄. The content of Fe distributed on the surface of MTW with 23.16% content of nano Fe₃O₄ was at 5.24%. The specific surface area of the MTW was increased by 85.71% when compared with TW. The saturated adsorption capacities of MB onto MTW was 160.5mg/g at 303K, which was higher than TW by 9.93%. The adsorbent showed a satisfactory regeneration and recycling utilization performances.

Montmorillonite and its derivatives are widely used adsorbent in environmental field. In this study, montmorillonite (MT-Na) and Fe₂O₃ modified montmorillonite (MT-Fe₂O₃) were used to remove catechol at various pH. Higher efficacy and faster removal of catechol was detected for MT-Fe₂O₃ than MT-Na. Catechol removal from solution was higher with MT-Na with increasing pH, while MT-Fe₂O₃ showed a reverse trend. Removal kinetics results showed fast and slow compartment of catechol removal involving adsorption and subsequent degradation of the latter. For MT-Fe₂O₃, fast compartment was attributed to adsorption and initial degradation. The retardation of catechol degradation rate manifested in the slow compartment was attributed to the hindrance of the active reaction sites by intermediate degradation products, Fe₂O₃ mediated generation of ·OH is central regarding removal of catechol using MT-Fe₂O₃. Efficient degradation of organic contaminants by montmorillonite underscores the importance of clay particles as capable adsorbent. This study will provide more precise assessment of the distinct contribution of clay particles in adsorption and degradation of catechol in environmental media.

The preparation of high-performance magnetic iron oxide (Fe₃O₄) pigment from pickling waste liquid and acid-washed sludge was explored by wet precipitation method. In the experiment, hydrogen peroxide was used as oxidant, 15% lime slurry was used to regulate the pH of reaction liquid, steam heating method was used as heating system. Based on the ratio of end-point Fe³⁺/Fe²⁺, the influence of sludge volume, Fe³⁺/Fe²⁺ratio, reaction time, pH and reaction temperature on the synthesis of Fe₃O₄ were analyzed. The results showed that the ratio of Fe³⁺/Fe²⁺ increased gradually under the influence of air during the reaction. Magnetic iron oxide pigment with high quality was obtained under the conditions of pickling wastewater/sludge ratio 5∶1, Fe³⁺/Fe²⁺ ratio 1.60∶1, reaction time 4h, pH 9 and reaction temperature 80－90℃. The color light and oil absorption of the product can reach the black iron oxide standard. This study could solve the bottleneck problem of the resource treatment of acid-washed sludge in the industry and bring economic and environmental benefits to enterprises.

Sequencing biofilm batch reactor (SBBR) is applied to sewage treatment. In order to investigate the effects of different sludge drainage stages on the pollutant removal and microbial community structure, three reactors were installed to treat domestic sewage. Activated sludge was removed in reactors at the initial, middle, and late culturing stages, respectively. Meanwhile, the microbial community structure and traditional microbial dominant species were analyzed by 16S rDNA high-throughput sequencing technology. Moreover, machine learning （ML） also played a role in excavating the sequencing data in depth and finding key species which led to the differences among groups. The water quality analysis results showed that there was no significant difference in COD removal efficiency among reactors with different sludge drainage stages, and the COD of effluent was all lower than 30mg/L. The NH₃-N removal efficiency of SBBR in sludge discharge in the middle stage was the first to reach a stable level and higher than that in the early and late stage of sludge discharge system. The results of high-throughput sequencing showed that the dominant microbial species in SBBR were mainly those that with high organic-pollutants-degrading capability. In SBBR, the NH₃-N removal related species (Hydrogenophaga, Gemmata and Nitrospira) screened by ML had higher abundance and stronger stability of microbial community structure, which could explain the difference of pollutant removal efficiency of SBBR from the microbial level.

In order to screen out environmental hormones for priority control in key industries of a city in East China, based on the US “Screening Plan for Endocrine Disruptors” and EU “Community Strategy for Endocrine Disruptors”, a list of environmental hormones including 51 chemicals was sorted out and the production and use of enterprises in key industries in the city were investigated. The results showed that among key 51 environmental hormones, including nonylphenol, bisphenol and ethoxamine, 13 of them were involved in the production and use of investigated key industrial enterprises. Furthermore, four of them, namely styrene, bisphenol A, diethyl phthalate and dibutyl phthalate, were screened as regional priority control environmental hormones, based on their production and consumption, as well as the enterprises involved in this city. The enterprises refer to four recommended regional priority environmental hormones are mainly located in chemical industrial park, and mainly involving chemical materials and chemical products industry. The results provide a theoretical basis for screening environmental hormones, further identifying their risks, and emphatically strengthening their management and control.