Bromine chloride is an important halogenating reagent in industry. Its synthesis has many challenges such as high heat release, low production efficiency and serious potential safety hazards. The continuity and miniaturization of producing equipment is an important development direction of bromine chloride synthesis technology. To develop microreaction technology for preparing bromine chloride via absorbing chlorine by means of dichloromethane solution of bromine, the mass transfer performances of Corning G1 reactor, Jinde C1 reactor and self-made micromixer + micro packed reactor were investigated. Continuous and stable preparation of bromine chloride was realized and the space-time yield of the microreactors reached 2.25g/(min∙mL). Bromination of polystyrene was implemented using the bromine chloride prepared from microreactors, and brominated polystyrene products with mass percentage >66% bromine content and 5% thermogravimetric temperature >370℃ were obtained.

In order to realize the efficient design of the surface structure of the micro-channel heat exchanger, the effects of cavity shapes (straight micro-channel, circular, rectangular and trapezoidal) and ovality on the flow and heat transfer performance of micro-channel were studied by means of numerical simulation and experiment, using supercritical nitrogen as the fluid medium, the mechanism of fluid efficient and low resistance heat transfer enhancement was revealed. The results showed that compared with the straight micro-channel, the entrance distance required for the SCN₂ velocity on the axis of the circular cavity micro-channel to reach a stable value was shorter, which was due to the fact that the cavity can promote the fluid flow/thermal boundary layer to be in the alternate state of destruction and reconstruction all the time. The shape of the fluid vortex in the circular cavity was consistent with the cavity geometry, and its flow resistance and heat transfer performance were optimal, followed by trapezoidal cavity micro-channel and rectangular cavity micro-channel. With the increase of ovality, the overall performance of cavity micro-channel increased firstly and then decreased. When the ovality was 1, the overall performance was optimal. The research results in this paper are of great significance for improving the design and manufacturing capability of micro-channel heat exchangers.

The heat transfer performance of a stirred tank with the four-pitched blade with stabilizing fins-Rushton combined impellers and helical coils was studied based on the combination of computational fluid dynamics (CFD) simulation and heat transfer experiments. The flow distribution, temperature distribution, temperature boundary layer and Nusselt number outside the coil were obtained. The results showed that the error of temperature between experimental measurement and numerical simulation was less than 4K. The high temperature area in the stirred tank was located in the circulating large eddy current area at the coil, and the maximum temperature difference was kept within 3K. The stabilizer fins could improve liquid axial-flow performance and make the temperature distribution of the stirred tank more uniform. The average temperature boundary layer thickness of XZ plane and YZ plane outside the inner coil was 3.01mm and 2.70mm, respectively. According to experimental data and numerical simulation, it was found that the order of influence of different factors on the Nusselt number outside the inner coil was as follows: viscosity of the mixing medium>mixing speed>blade spacing>distance from the bottom. The maximum error of Nusselt number between experiment and simulation was 14.56%, and the minimum error was 4.23%, which verified the feasibility of numerical simulation well. The research results can provide a reference for the application of the four-pitched blade with stabilizing fins-Rushton combined impellers in the practical industry.

The safety of the pipeline is decreased by the periodic suction and discharge features of the reciprocating compressor, which are easily responsible for pipeline pulsation amplitudes that are too high. As a result, this research studied the secondary compression discharge line of a skid-mounted reciprocating compressor set with substantial pressure variations, employing numerical simulation methods to investigate pipeline airflow pulsation characteristics. According to research, the cylinder dynamic compression process, valve opening and shutting caused secondary compression exhaust pressure variations, and pipeline pressure pulsation amplitude exceeded the API 618 requirement. The secondary exhaust pipe’s vibration test was conducted concurrently to ensure the validity of the modeling method and findings. In order to solve the issue of the secondary exhaust pipe’s airflow pulsation amplitude exceeding the standard, the influence of the filter pipe on the pipe’s airflow pulsation amplitude was examined, and an optimization study was conducted based on the orthogonal test to reduce the pipe’s airflow pulsation amplitude. According to the results, the maximum pressure pulsation of the optimized pipeline was 37.02kPa, 38.36% less than that prior to optimization, and the pipeline safety index was 80.4% higher, which lowered the risk of pipeline damage and increased the safety and stability of the reciprocating compressor set.

In this study, a saw-like microchannel was proposed to enhance convective heat transfer. The fluid flow and heat transfer characteristics of this proposed microchannel were numerically investigated using COMSOL software. The effect of saw-like microchannel on fluid flow and heat transfer performance were studied in both forward and backward direction. The Reynolds number (Re) ranged from 50 to 700. The numerical results indicated that the present microchannel configuration greatly strengthened the spatial mixing of fluid and significantly disturbs the thermal boundary layer, leading to dramatic enhancement of convective heat transfer. Compared to conventional microchannel, Nusselt number (Nu) was significantly enhanced by 102.7%. Additionally, fluid flow and heat transfer characteristics of this saw-like microchannel in both forward and backward directions were investigated. At Re=700, the Nu in the backward direction was increased by 20% compared to that in forward direction. However, the pressure drop was magnified about 110%.

Combustion of adding hydrogen in industrial gas boilers can reduce the use of carbon-containing fuels, but it will cause an increase in NO _x emission. Therefore, this paper conducted a detailed study on the hydrogen mixed combustion characteristics of an existing industrial gas-fired HL75-2.5/260-Q boiler. The formation law and reduction path of NO and N₂O were explored to provide a fundamental guide for the subsequent development of low-nitrogen burners for hydrogen mixed combustion. Firstly, based on the detailed reaction mechanism of methane Gri-mesh 3.0, the combustion characteristics and pollutant formation characteristics of gas with a hydrogen content ratio of 0—90% were simulated. Secondly, the chemical reactor network model inside the boiler was established by Chemkin, and the generation path, sensitivity, and production rate characteristics of NO and N₂O under the optimal hydrogen mixing ratio were analyzed. The results showed that when the excess air coefficient was 1.2, the high-temperature area of the flame and the outlet temperature increased with the increase of the hydrogen doping ratio. The outlet NO concentration gradually increased from 85.59mg/m³ to 249.85mg/m³. The N₂O emission first decreased and then increased, and the N₂O emission was at least 0.16mg/m³ at the hydrogen mixed ratio of 0.2. NO mainly came from the elementary reactions R179 (N + O₂ NO + O) and R180 (N + O₂ NO + O)), and N₂O mainly came from the elementary reaction R185 [N₂ + O(+M) N₂O(+M)].

Guangdong is rich in agricultural and forestry waste resources. Promoting the multi-channel resource utilization of agricultural and forestry waste conforms to the national requirements of energy conservation, emission reduction and green development, and is a major task of environmental protection and governance in urban and rural areas of Guangdong. It is also of great significance to help the “double carbon” strategy. This paper reviews the energy and chemicals production from agriculture and forestry waste resource via the technology route of direct combustion/gasification power generation, methane, green hydrogen, biodiesel fuel and methanol preparation as well as the electrochemical application. Also, the development and challenges of different technical paths are analyzed to reveal the utilization prospects of agricultural and forestry wastes resource. Finally, we propose suggestions to promote the development of agriculture and forestry waste resource utilization. It is expected to provide a universal model and theoretical support for the conversion and development of biomass energy under the constraint of “carbon peaking and carbon neutrality” goals, promoting the multi-channel efficient resource utilization of agricultural and forestry wastes in Guangdong.

Biodiesel is a green low-carbon liquid fuel. Poor oxidation stability and tendency to corrode metals limit its large-scale application. In this study, tetraethylenepentamine (TEPA) and tert-butylhydroquinone (TBHQ) were compounded to an highly effective inhibitor of oxidation-corrosion taking Jatropha biodiesel as the object of study. The Rancimat method, scanning electron microscope and other characterization methods were used to investigate the effect and mechanism of the oxidation-corrosion inhibitor on the oxidation stability and corrosion performance of biodiesel. The results showed that the oxidation induction period was increased from 4.24h to 7.83h by adding 0.1‰ inhibitor with the ratio of 4∶1 oxidation-corrosion into Jatropha biodiesel. Meanwhile, it had better corrosion inhibition. The corrosion grade on a copper strip of biodiesel was decreased from 3a to 1a, the carbon element on the surface of the copper strip was reduced from 10.5% to 8.5%, and the oxygen element was decreased from 10% to 0. TEPA chelated Cu²⁺, and TBHQ provided H radicals to interrupt the biodiesel auto-oxidation chain reaction. TEPA could provide H radicals to restore and regenerate the used TBHQ. The combination of the two had a good synergistic effect, which could improve biodiesel oxidative stability and corrosion. This study provided theoretical support for the large-scale application of biodiesel.

Aiming at the problem of restart-up for heavy oil-water ring transportation pipeline due to instability and damage of the water ring, based on the self-developed design of small indoor loop simulation experimental device, taking four kinds of ordinary heavy oil in Luda oilfield as the research object, the change law of restart-up pressure drop with time was experimentally studied when the pipeline was restarted-up after shutdown at constant water flow. The effects of oil holdup, oil viscosity, shutdown time as well as constant water flow velocity on the restart-up pressure drop were discussed. The regression analysis on the results of orthogonal restart-up experiment was conducted by IBM SPSS software, and a multivariate nonlinear regression model of restart-up pressure drop was established, the prediction reliability of which was verified through 192 groups of experimental data. The experimental results showed that the variations of restart-up pressure drop with time can be divided into two stages: attenuation stage and equilibrium stage. The restart-up pressure drop was positively correlated with oil holdup, oil viscosity, shutdown time and constant water flow velocity, but the influences of oil holdup and constant water flow velocity were the most significant. The predicted values of restart-up pressure drop were in good coincidence with the measured ones, and the relative error are within the range of ±10%.

For the 18650 ternary lithium battery in the high rate cycle charge and discharge, the battery pack temperature is higher than its safe operation range due to the untimely heat dissipation, which causes the safety problems such as spontaneous combustion. A new composite phase change material (CPCM) of paraffin-hexadecanoic acid was prepared, and the heat dissipation mode of the composite phase change material-heat pipe (CPCM-HP) coupling was proposed. When paraffin-hexadecanoic acid mixing ratio was 3∶1, the best heat dissipation effect was achieved, possessing the lowest phase change temperature of 43.3℃, which was reduced by 11.8% relative to pure paraffin. Under 3C discharge, the maximum temperature and maximum temperature difference of CPCM-HP were reduced by 7.1℃ and 1.4℃, respectively, compared with CPCM heat dissipation system. For CPCM-HP heat dissipation mode at 30℃ under the “3C discharge-1C charge” mode, the battery pack was maintained at about 46.5℃, the maximum temperature did not exceed 50℃ during the whole cycle, and the maximum temperature difference was controlled below 1.5℃, that is, the battery pack was always kept within the safe temperature range. The experimental results showed that CPCM-HP has better heat dissipation performance than CPCM.

Molecular dynamics simulation was used to study the formation process of methane hydrate in the wet fixed bed filled with two representative metal-organic framework materials (MOF materials) ZIF-8 and ZIF-67. The results showed that compared with ZIF-67, ZIF-8 material with the stronger adsorption capacity of methane gas can eventually induce more methane and water molecules to convert into hydrates, which was conducive to the natural gas storage by using hybrid adsorption-hydration technique. However, the excellent adsorption property of ZIF-8 on methane will also reduced the concentration of methane in solution, weakened the driving force of hydrate formation, and significantly prolonged the growth time of hydrate by promoting the migration of methane molecules in the solution to the surface of ZIF-8 material and aggregating into nano-bubbles. Therefore, when selecting porous materials suitable for the hybrid adsorption-hydration natural gas storage technology, it was necessary to comprehensively consider the natural gas adsorption characteristics of the dry materials themselves and the hydrate formation kinetics of the fixed bed as a whole.

Nanofluids consist of basefluids and nanoparticles, which have attracted wide attention because of their favorable thermal properties. The thermal conductivity of nanofluids is greatly affected by particles aggregation which is one of the significant characteristics of nanofluids. Currently, it is difficult to observe the microscopic changes in nanofluids from uniform dispersion to agglomeration by experimental method. The non-equilibrium molecular dynamics (NEMD) method was performed to investigate the Brownian motion of basefluid atoms and interfacial layer properties during particle agglomeration of Cu/Ar nanofluid. The mechanism of the effect of agglomeration behavior on the variation of thermal conductivity was obtained by analyzing microscopic parameters such as mean square displacement (MSD) and number density. The results showed that the thermal conductivity of nanofluid gradually increased during the process of nanoparticles from uniform dispersion to complete agglomeration, and the thermal conductivity obtaind the maximum value when the particles were agglomerated. Comparing the MSDs in the two states of uniform dispersion and complete aggregation of the particles, the MSD value of the base fluid atoms of fully agglomerated state increased by about 3% compared to that of uniformly dispersed state, showing that the Brownian motion of the base fluid atoms of fully agglomerated state was enhanced. Meanwhile, the MSD of the interfacial layer of fully agglomerated state decreased by about 22% compared to that of uniformly dispersed state, indicating that the atoms in the interfacial layer were less active and the interfacial layer tended to be stable. Furthermore, the aggregation structure of the particles was investigated. The agglomerated structures can be classified into reaction-limited agglomerates (21Å,1Å=0.1nm) and diffusion-limited agglomerates (22Å) by varying the initial particle center-of-mass distance. After increasing the number density of the nanofluidic interfacial layer from the initial value of 67nm^-3 to 72nm^-3, the reaction-limited agglomeration shifted to diffusion-limited aggregation. After decreasing the number density of the nanofluidic interfacial layer from the initial value of 67nm^-3 to 62nm^-3, the diffusion-limited aggregation shifted to reaction-limited aggregation. The results showed that the density of interfacial layer was one of the main factors affecting the aggregation structure of nanoparticles.

It is a promising way for ethylene production by oxidative dehydrogenation of ethane. MoVTeNbO _x catalyst has the advantages of high activity and strong redox ability, and it is currently the research focus of oxidative dehydrogenation of low carbon alkanes. In this work, the research progress of MoVTeNbO _x composite metal oxide in the oxidative dehydrogenation of ethane to ethylene was systematically reviewed, including the crystalline phase structure and the active center of catalyst, the preparation of catalysts, influencing factors of catalytic conversion of ethane and the improvement of catalyst performance. The main research directions at present are the regulation strategy of the active center of polymetallic oxide catalyst, the optimization of the interactions among the oxides, optimizing the preparation conditions, improving the redox ability of the catalyst and the content of V⁵⁺ on the surface through the regulation of additives, and thus improving the oxidative dehydrogenation activity and operational stability, so as to provide the foundation for the large-scale production and industrial application of the catalyst. Finally, the development prospect of MoVTeNbO _x mixed metal oxide in oxidative dehydrogenation is given.

Hydrogenation of carbon-oxygen bonds to produce alcohol is a significant hydrogenation reaction with wide applications, such as the hydrogenation of CO, CO₂, esters, carboxylic acids, anhydrides, and furfural. In the reaction process, the catalyst is the key to determine the degree of reaction and the distribution of hydrogenation products. The development of copper-based catalysts with high activity and selectivity to replace precious metals has research value and reference significance for the industrial application. Based the most two serious problems of copper-based catalysts, i.e. facile sintering and agglomeration at high temperatures, the researches of copper-based catalysts in the carbon-oxygen bond hydrogenation reaction are reviewed. The methods to avoid catalyst inactivation and increase catalyst stability are introduced, and the stability enhancement of copper-based catalysts by adding different additives, support effects, and constructing special catalyst structures, are discussed. The factors influencing the catalyst stability such as high oxygen vacancy to promote defect and adsorption sites, and confinement to restrict metal migration and aggregation, are summarized.

In order to study the synergistic effect between Mo₂C and Co on the catalytic hydrolysis of ammonia borane to hydrogen, Co-30Mo₂C/CNTs nanomaterial was prepared by a step impregnation method. The synthesized catalysts were characterized by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy, and their catalytic performance of ammonia borane hydrolysis was tested. The results showed that Co-30Mo₂C/CNTs was successfully synthesized, Co and Mo₂C were evenly dispersed around CNTs. Mo₂C grew into rod-shaped structures locally, which could play a supporting role for the agglomerated CNTs, and hence the catalyst possessed more voids and exposed more active sites. The binding energies of Co and Mo in Co-30Mo₂C/CNTs, 30Mo₂C/CNTs and 10Co/CNTs were analyzed. It was found that there was partial electron transfer, which improved the catalytic activity of Co-30Mo₂C/CNTs. The hydrogen production rate of Co-30Mo₂C/CNTs was the highest, reaching 11866. This excellent catalytic activity can be attributed to the synergistic effect between Co and Mo₂C. The addition of Mo₂C enhanced the activation of H₂O molecules. After five cycles of stability test, 75% of the activity were retained, which is of significance for the recyclability of non-precious metal catalysts.

The electrocatalysts of CO₂ reduction have become a hot research topic in catalysis in recent years, but CO₂ reduction is often accompanied by competing hydrogen evolution reactions, which directly lead to energy wastage. In this paper, a zinc-magnesium bimetallic hydroxide [ZnMg(OH)₄] with high efficiency in reducing CO₂ to CO was prepared by hydrothermal synthesis, and a cationic surfactant was introduced to inhibit the hydrogen evolution reactions. ZnMg(OH)₄ was used as the carrier to coat the cationic surfactant cetyl trimethl ammonium bromide(C₁₉H₄₂BrN,CTAB) by spraying method to form ZnMg(OH)₄-CTAB composite catalyst. The crystal structure and morphology of the catalyst were also characterized, and the electrocatalytic CO₂ reduction electrochemical tests. At a potential of -1.5V (vs. RHE), surface coating with a cationic surfactant increases the performance of the catalyst was evaluated by a series of CO Faraday efficiency of the sample from 78.2% to 87.25%. The results showed that the composite catalyst ZnMg(OH)₄-CTAB formed by coating a cationic surfactant on the catalyst surface has excellent carbon dioxide reduction performance, which was related to the synergistic effect of the cationic surfactant and bimetallic hydroxide.

In order to enhance the performance of low-temperature denitration catalyst, a series of nitrogen doped vanadium titanium honeycomb catalysts were prepared by extrusion molding. The effect of nitrogen doping amount on the low-temperature activity and stability of the catalyst were discussed. The catalysts were characterized by XRD, BET, SEM, XPS, H₂-TPR, NH₃-TPD and O₂-TPD. The results showed that nitrogen doping significantly enhanced the low temperature denitration performance of the catalysts, which worked well in the temperature range of 140—200℃. Among them, the catalyst with the molar ratio of nitrogen to titanium of 0.2 had the best deNO _x efficiency. During the 72-hours stability test at 200℃, the NO conversion rate was basically kept at 86.6%. Nitrogen doping could reduce vanadium titanium catalyst particle size, increase the specific surface area and pore volume, as well as the ratio of surface V⁴⁺and chemically adsorbed oxygen O_α. With the increase of the acidic sites on the surface, the adsorption capacity of NH₃ on the catalyst surface was increased, leading to the enhanced redox capacity and the improved low temperature denitration performance of the catalyst.

The highly selective catalytic transfer hydrogenation of furfural to furfuryl alcohol is one of the important routes for high value utilization of biomass. Herein, UiO-66 catalysts with the different defect sites were prepared with formic acid, acetic acid and trifluoroacetic acid as regulators. The catalyst was characterized by XRD, SEM, NH₃-TPD, TG and N₂ adsorption and desorption. The effects of defects, acidity and textural properties of UiO-66 catalysts on the transfer hydrogenation of furfural were investigated with isopropanol as both solvent and hydrogen donor. The results showed that the enhancement of acidity of UiO-66 catalysts was beneficial to the improvement of furfuryl alcohol selectivity in furfural transfer hydrogenation reaction. The furfural conversion and selectivity to furfuryl alcohol over UiO-66 prepared with formic acid as regulator could reach 99.4% and 98.9% at 160℃ in 1h, respectively.

With the rapid development of human society and industry, mercury emissions have brought great hidden dangers to the ecological environment and human health. The common methods of mercury treatment include chemical precipitation, ion exchange, adsorption and so on. Among them, the chemical precipitation method can effectively remove most of the mercury in the wastewater, but the amount of sulfide is difficult to control, which is easy to cause water quality hardening and secondary pollution. The ion exchange method has the advantages of high quality water, simple equipment, fast mercury absorption and no secondary treatment. But it has not been widely used because of the limitation of the type, dosage and cost of exchangers. The adsorption method usually does not introduce new pollutants into the treated water, having high mercury removal rate, easy operation and good selectivity, and thus the research and development of related technologies has more potential. Polymers-Chalcogenide Hybrid Inorganic/Organic Polymers (CHIPs) prepared by inverse vulcanization method is a new type of high-efficiency mercury adsorbent, which provides a new idea for addressing mercury pollution. In this review, the basic principle of reverse vulcanization was introduced. The different methods of preparing porous CHIPs from the pore-forming agent, carbon dioxide foaming, electrospinning and carbonization were reviewed. Furthermore, the mercury adsorption mechanism of porous CHIPs and its application in the field of mercury adsorption were summarized. Finally, the development prospect of porous CHIPs was prospected. It was pointed out that the porous CHIPs with biocompatibility and degradability would be the focus of further research, while the toxicity of porous CHIPs and the application of mercury adsorption in atmosphere and soil would also become an important research direction, which broadened new ideas for the application of porous CHIPs in the field of mercury adsorption.

With the development of lithium batteries, aerospace and other industries, there is an urgent need to develop lithium resources efficiently. Membrane technology with the advantages of low energy consumption and simple operation is widely used in Mg-Li separation. Metal-organic frameworks (MOFs) have such characteristics as rich topology, large specific surface area and stable porosity, and thus they can be used to develop ideal membrane materials for Mg-Li separation. This paper highlighted an overview of the main types and preparation strategies of MOFs-based membranes, focused on comparing Mg-Li selectivity of MOFs polycrystalline membranes, MOFs polyamide membranes and MOFs channel membranes, and analyzed the key mechanisms behind Mg-Li selectivity (involving size sieving effects, ion-group interactions, dehydration-rehydration mechanisms and Donnan theory). Moreover, MOFs-based membranes improvement for Mg-Li separation was prospected, including MOFs selection and modification, optimization of substrate preparation methods and substrate modification. Finally, it’s expected to further improve the selectivity of Mg-Li and the stability of MOFs-based membranes, and provide new ideas for application promotion.

Safety accidents of lithium-ion batteries (LIBs) caused by impact, puncture and other external forces have become one of the main bottlenecks restricting their development and application. Shear-thickening electrolytes are designed by introducing specific nano-additives into traditional electrolyte to improve the impact resistance of LIBs. This review mainly discusses the definition, properties, principles, and influencing factors of shear-thickening fluids and their recent applications in LIBs. This review aims to summarize the relationship between the synthesis methods of shear-thickening electrolytes and their properties. It also suggests that the surface modification of nanoparticle fillers, the increase of length-width ratio and concentration can enhance the thickening properties of the electrolytes. Finally, it is suggested that the future development of shear thickening electrolytes is to design new functional nano-fillers to achieve the simultaneous improvement of thickening properties and electrochemical performance.

Layered double hydroxides (LDHs) as new functional materials were widely used to remove pollutants due to their excellent adsorption and catalytic performances. In this study, the clustering data analysis over the past decade were conducted based on keyword retrievals. The preparation of LDHs as well as modification methods were introduced. The application in environment treatment and remediation was summarized. The modification of LDHs was studied to enhance the adsorption and catalytic performances of LDHs, thus increasing their adaptability and expanding their application. Specifically, the removal and degradation mechanisms of organic pollutants, including dyes and antibiotics by LDHs in dye, pharmaceutical and poultry wastewater were discussed in detail. The influence factors on the removal of heavy metals from mining and smelting wastewater by LDHs were analyzed. The treatment of nitrogen and phosphorus in eutrophic water body were summarized. In addition, the application of LDHs in farmland soil remediation and CO₂ capture with recycling was clarified. This paper made a comprehensive summary of the application of LDHs in the field of environment, and pointed out the limitations and challenges of LDHs research, providing direction and ideas for future research.

Polyimide (PI) matrix is a ubiquitous solid lubricating organic polymer material in shafts, gears, brakes and microelectronics due to superior thermal resistance, mechanical properties, chemical stability and low dielectric constants. However, the high friction coefficient and poor wear resistance of pristine PI severely limit further application and reduce service life. Firstly, this paper summarizes the latest research progress of tribological performance of PI by introducing zero-dimensional (0D), one-dimensional (1D) and two-dimensional (2D) lubricating phase materials. The anti-friction and anti-wear mechanism on PI by adding different single-dimensional lubricating phase materials are discussed in detail. Secondly, the lubricating effect of multidimensional (0D-1D, 0D-2D, 1D-2D) hybrid lubricating materials on PI matrix is analyzed. Multidimensional hybrid lubricating materials show the optimal tribological properties for PI matrix compared to single-dimensional materials. Thirdly, the influence of different dimensional lubricating phase materials on the mechanical properties of PI-based composites is further reviewed. Finally, it is pointed out that the future research trend of PI-based solid lubricating composites should be focused on the friction behavior under different working conditions in addition to the development of new lubricating materials, while revealing the mechanism of lubrication between PI and lubricating phase through simulation studies.

Due to the worsening global climate change and the increasing extreme weather events, CO₂ capture and separation has important strategic significance and relates to human survival. In recent years, new materials for CO₂ capture and separation have emerged. Among them, ionic liquids (ILs), as a new alternative to organic solvents, have received tremendous interest due to the tunable chemical structures and unique physicochemical properties, such as low volatility, high thermal stability and excellent solubility. And metal-organic frameworks (MOFs) have also been considered as fascinating porous materials for CO₂ capture and separation. In this paper, the research progress of CO₂ capture and separation by ILs/MOFs composites is summarized. The adsorptive separation via MOFs-supported ILs, ILs-modified MOFs, dispersing MOFs in ILs to form porous liquids, and membrane separation are all discussed, as well as the advantages and disadvantages of each method. In addition, the application prospect and development of ILs/MOFs composites in CO₂ capture and separation are also discussed.

Leakage prevention and thermal conductivity improvement of phase change materials are two key issues for energy storage of phase change materials. In this work, nano-TiO₂@n-docosane microcapsules were prepared by fine emulsion interfacial polymerization using tetrabutyl titanate (TBT) as precursor. The formation process was observed by biomicroscopy, and the properties of nano-TiO₂@n-docosane microcapsules were characterized by scanning electron microscope (SEM), differential scanning calorimeter (DSC), thermal conductivity meter and thermogravimetric analyzer. The experimental results showed that the formation process of nano-TiO₂@n-docosane microcapsules was that the number of nano-microcapsules changed from less to more, the particle size from small to large, the interface of microscopic solution from blurred to clear, and the aging and cooling process of solution was gradually from gelation suspension state to powder precipitation state. The results of SEM test indicated that the particle size of nano-TiO₂@n-docosane microcapsules was significantly related to rotational speed, and the appearance was closely related to the dosage of TBT, hydrochloric acid (HCl) and sodium dodecyl sulfate (SDS). The DSC results showed that the melting and solidification temperatures were 41.3℃ and 42.4℃, respectively. The latent heat of nano-TiO₂@n-docosane was 178J/g. The coating rate and the coating efficiency were 70.7% and 69.0%, respectively with the heat storage capacity of 97.6%. The average thermal conductivity of nano-TiO₂@n-docosane microcapsules was 215% of n-docosane. It was found from the infrared spectrum test that there was no chemical reaction when n-docosane and TiO₂ were physically combined. The results of thermogravimetric analysis indicated that TiO₂ formed a physical protective barrier and slowed down the diffusion of n-docosane outside the capsule.

All kinds of eco-friendly biomass can be used as green carbon source to prepare carbon quantum dots (CQDs), a novel zero-dimensional carbon nano luminescent material. In this paper, biomass-based CQDs were prepared by one-step hydrothermal method using agricultural and forestry waste, garden and kitchen waste as raw materials. High resolution transmission electron microscopy, Raman spectroscopy, Fourier infrared spectroscopy, X-ray photoelectron spectroscopy, UV-visible absorption spectrum and fluorescence spectroscopy were used to characterize various types of CQDs, and to explore the influence of biomass on the fluorescence properties of CQDs. The experimental results showed that: All kinds of biomass-based CQDs emit blue fluorescence under UV excitation, and the fluorescence quantum yield (QY) of CQDs prepared by agricultural and forestry waste was generally low. The fluorescence QYs of CQDs prepared by egg shell, Chinese parasol leaves and lemon peel reached 9.29%, 9.03% and 4.51%, respectively. The three kinds of biomass and the prepared CQDs all contained N or S element. It showed that the biomass naturally containing N or S elements was helpful to improve the fluorescence QY of CQDs. By making phosphors from biomass-based CQDs, the optical properties of the light-emitting diode (LED) produced showed a certain mapping relationship with the fluorescence properties of CQDs. Relevant conclusions provide strong guidance for the green synthesis of biomass-based CQDs and the green preparation of LED.

The surface modification of ground calcium carbonate (GCC) was accomplished by mechanically activated of GCC, sodium polyacrylate and nano calcium carbonate together and the CaCO₃ composite coated with nano calcium carbonate was applied to the adsorption of Cu²⁺ in solution. The adsorption properties were also investigated. The results showed that SEM and XRD analyses confirmed that the nano calcium carbonate was successfully coated on the surface of GCC. FTIR analysis found that the hydroxyl groups increased on the composite surface, and BET analysis indicated that the specific surface area of composite was 20.5m²/g with a mesoporous structure. The maximum adsorption capacity of composite calcium carbonate for Cu²⁺ was 65.5mg/g and the removal rate could reach 98%. The absorption process studies revealed that the adsorption kinetics followed the pseudo-second-order kinetic model and the adsorption isotherms followed the Langmuir-Freundich model, proving that the adsorption was dominated by ions exchange and was exothermal.

Porphyra is not only inexpensive and easily available but also rich in protein. Employing porphyra as raw material to provide carbon and nitrogen sources, crude carbon was first prepared by pre-carbonization. Subsequently, it was further activated by KOH to create numerous pores in the final product, thus achieving the fabrication of nitrogen-doped hierarchical porous carbon. When the ratio of KOH to crude carbon was 2∶1, the resulting nitrogen-doped porous carbon (NDHPC-2) possessed the most abundant porosity and the best honeycomb-like hierarchal porous structure, whose specific surface area, mesopore percentage and nitrogen doping content were 1975.2m²/g, 41.2% and 4.3%, respectively. Moreover, the electrochemical tests in a three-electrode system showed that the NDHPC-2 electrode released a maximum specific capacitance of 185.4F/g with splendid rate performance, coulombic efficiency and cycle stability. Based on this carbon material, a symmetric supercapacitor (NDHPC-2//NDHPC-2) was built, which offered a largest energy density of 6.7Wh/kg and still maintained outstanding rate capability, coulombic efficiency and cycling durability. For example, when consecutively charged/discharged at a high current density of 10A/g for over 10000 cycles, the coulombic efficiency of such device was close to 100% from beginning to end and its capacitance decay was almost negligible during the whole experiment as well. The supercapacitive properties of NDHPC-2 porous carbon, both in three- and two-electrode systems, were comparable or even superior to those of many reported porous biomass carbon materials, therefore exhibiting excellent advantages for energy storage and promising potential toward practical applications.

High-speed cameras were used to capture the impact of deionized water droplets, three relative molecular masses of polyethylene oxide (PEO) droplets, bis(2-ethylhexyl)sulfosuccinate (AOT) droplets of surfactant and a combination of two additives on the surface of lotus leaves. Comparative analysis of the deposition characteristics of droplets with different characteristics on the leaf surface were studied by comparative analysis. The experimental results showed that PEO additives could significantly inhibit droplet rebound and increase droplet residence time on leaf surface, and prevent outward emission of satellite droplets. The inhibition effect of high relative molecular mass PEO (5×10⁵, 2×10⁶) was more obvious, but it would reduce the spreading area of droplets on the leaf surface. Low mass fraction (0.005%, 0.02%) of AOT additives could increased the spreading area of droplets on the leaf surface, reduced the droplet pop-up height and wet the local impact area, but at high impact velocities (v>1.66m/s), the droplets would break multiple satellite droplets and eject from the leaf surface during contraction. At increasing the AOT mass fraction at 0.1%, the droplets were able to wet the leaf surface at the spreading stage and spread to a larger area in a short time. A mixture of droplets using both PEO and AOT additives combining the advantages of polymers and surfactants, was capable of forming filaments that draw drew droplets in the localized wetted areas, enhancing the effective deposition of droplets on the leaf surface. By compiling and analyzing the experimental data, it was found that droplets were more likely to be deposited on the leaf surface by increasing the Weber number (We) while decreasing the Reynolds number (Re).

Carotenoids are widely used as fat-soluble natural pigments and antioxidants. Here we chose Rhodopseudomonas palustris, a typical purple nonsulfur photosynthetic bacteria, to produce carotenoids under photo-anaerobic conditions. The effects of culture conditions such as organic acid types, salt concentration and light intensity on the cell growth, carotenoid content and composition were studied, and the antioxidant activities of carotenoids were also explored. The results showed that lactic acid as carbon source produced the highest biomass and carotenoid content among the eight organic acids tested. The optimum light intensity (500lx) for carotenoid content was lower than that required for the growth of Rhodopseudomonas palustris (2000lx). High salt concentration promoted the synthesis of carotenoids, and the optimum concentration (7.5g/L) was three times that required for its growth. Under optimized conditions, the carotenoid content reached 15.35mg/L. Six kinds of carotenoids were detected, and the composition was greatly affected by the culture conditions. High salt concentration and strong light favored the synthesis of 3,4-didehydrorhodopin, which might be a mechanism for photosynthetic bacteria to adapt to environmental stress. The antioxidant activity test and data analysis showed that antioxidant activities of the produced carotenoids highly depended on their composition, and OH-spirilloxanthin and 3,4-didehydrorhodopin showed strong antioxidant activities.

The addition of plant growth regulators is a currently promising strategy to promote DHA accumulation in Schizochytrium sp. and increase its yield. The addition of a single plant growth regulator has been reported to promote the accumulation of DHA in Schizochytrium sp., but the synergistic promotion of DHA accumulation in Schizochytrium sp. by the addition of two plant growth regulators at the same time has rarely been reported. In this study, two plant growth regulators, diethyl aminoethyl hexanoate (DA-6) and 2,4-dichlorophenoxyacetic acid (2,4-D) were used to synergistically induce the accumulation of DHA in Schizochytrium sp., increasing the content and yield of DHA. The synergistic concentration of DA-6 and 2,4-D was optimized using DHA as an indicator. The results showed that when 0.05mg/L DA-6 combinating with 0.5mg/L 2,4-D was used, the biomass and oil contents did not significantly increase, compared to supplemented DA-6 group and control group without plant growth regulator. But the DHA content and yield increased significantly and reached the highest values, which were 58.32% and 5.17g/L, respectively. Compared to supplemented DA-6 group, DHA content and yield increased by 0.17 times and 0.23 times, respectively; compared to control group without plant growth regulator, DHA content and yield increased by 0.48 times and 0.48 times, respectively. The results of this work indicated that synthetic plant growth regulators with appropriate concentration could synergically induce DHA accumulation in Schizochytrium sp. to increase DHA production, which provided a new idea and strategy for large-scale industrial production of DHA.

The genetic engineering Shewanella oneidensis (SO) strain was used as a biological template, to synthesize ternary SO/CdS/ZnO integrated photocatalysts, wherein, the recombinant SO strain could overexpress cysteine desulfurase for the extracellular growth of CdS nanoparticles by adding L-cysteine and cadmium ions, and zinc oxide nanoparticles were further loaded. The physicochemical properties of SO/CdS/ZnO photocatalysts were characterized by SEM, TEM, EDX, XRD, and XPS. The catalytic performance was evaluated in the photocatalytic degradation of organic dyes. The results showed that CdS and ZnO nanoparticles were uniformly loaded on the external surface of the recombinant SO strain. The as-prepared integrated nanocatalysts could effectively photodegrade organic dyes, and the amount of zinc source showed a significant effect on the degradation efficiency. When the amount of zinc acetate was 0.22g, the best photodegradation performance was achieved, e.g., the photodegradation efficiency of organic dyes could reach 100% within 60min. Moreover, the ternary integrated nanocatalysts could be reused 5 times with more than 80% of the original photodegradation efficiency. It was found that CdS nanoparticles could produce photogenerated electrons and holes under light irradiation, while ZnO nanoparticles inhibited the recombination of e^- and h⁺, and their synergistic effect improved the photodegradation efficiency. Accordingly, we provide a simple and feasible synthetic route for the multicomponent photocatalysts, and particularly we demonstrate that the assembly of semiconductor nanoparticles on the genetic engineering microorganisms as a platform has promising prospects in photocatalysis.

Silica scaling led to irreversible decline of the nanofiltration/reverse osmosis (NF/RO) membrane permeation flux and severely limited the water productivity of the membrane system, which was widely considered as a difficult challenge in water treatment process. Two types of silica scale on NF/RO membrane were introduced firstly, namely inorganic scale and combined inorganic-organic scale. Then, the effects of influent water quality, membrane surface chemical properties and topology on the formation of silica scale on membrane surface were emphatically reviewed, as well as the control strategies for the formation of silica scale on membrane surface, including influent pretreatment, scale inhibitor addition, membrane surface chemical modification and morphology regulation. Finally, the existing problems and future research directions of silica scaling control on membrane surface were summarized, mainly including the research on silica scaling behavior using model substrates with controllable surface properties, the in-depth exploration of the relationship between membrane surface chemical properties and silica scaling potential, the thorough research on the delay and inhibition mechanism of polymer scale inhibitors at the molecular level, the development of novel membrane materials to simultaneously inhibit silica scaling and organic fouling, and the establishment of a comprehensive database related to membrane surface properties and silica scaling under different influent water quality conditions, which were of important guiding significance for the development of efficient silica scale control strategies.

With the acceleration of industrialization, the types and discharge of wastewater are increasing, which has caused serious harm to the natural environment and human society. Therefore, it is urgent to develop economical and efficient wastewater treatment technology. Bio-electro-Fenton (BEF) system is a water treatment technology which combines bioelectrochemical system with Fenton oxidation process. As a high efficiency, green and energy saving approach, BEF system is attracting a growing interest recently. Here, the work principle of BEF system was introduced. Main factors influencing the properties of anode and cathode were discussed, including the extracellular electron transport process of microorganisms, anode materials, cathode materials, catalysts of Fenton reaction and system operating conditions. The application of BEF system in various wastewater (dye wastewater, pharmaceutical wastewater, landfill leachate, coal chemical wastewater and swine wastewater) treatment was summarized. Finally, the current challenges and future research directions of BEF system were pointed out, including developing the efficient electrode materials and catalysts, coupling with other water treatment processes, reducing the cost of membrane materials and conducting pilot studies, in order to support its further development.

The H₂S gas generated in coal gasification is easy to cause problems such as downstream equipment corrosion, catalyst poisoning and environmental pollution. Molecular sieve supported desulfurizer has been widely used in H₂S purification because it could highly disperse the active components and promote mass transfer during the reaction. Based on the pore size and pore structure characteristics of molecular sieve, this paper introduced the application status of micropore (d<2nm), mesopore (2nm<d<50nm), macropore (d>50nm) and hierarchical porous molecular sieve, as well as the desulfurizer with molecular sieve structural characteristics as the carrier in the adsorption of H₂S gas from high temperature gas. The advantages and disadvantages of different types of molecular sieve-based desulfurizers were analyzed and discussed. Finally, the structural characteristics of different molecular sieve carriers, the research status and performance improvement of molecular sieve-based desulfurizers for H₂S purification, desulfurization functionalization and green preparation processes were concluded and prospected to provide a useful reference for the development and application of molecular sieve-based supported desulfurizer in the future.

Membrane technology has been widely applied in the wastewater treatment; however, membrane fouling hinders its further applications. The exploitation of antifouling membranes to achieve energy saving and consumption reduction has been a one of hot topics. As a kind of surface modification strategy, the layer-by-layer (LbL) self-assembly technique has been explored in the antifouling membrane preparation due to its characteristics of diverse assemble-materials, widely practical scenarios, mild preparation conditions and molecular-scale controllability. In this review, on the basis of clarifying the mechanism of LbL self-assembly technique applied in the membrane fouling control, the effects of selection and pretreatment of base membranes, types of antifouling units and its combination with membranes, the number of assemble layers and preparation methods on the antifouling performance of membranes were summarized. Overall, perspectives of development on the antifouling membranes based on LbL self-assembly technique for wastewater treatment were proposed, such as excavation of the mechanism of assembly process, optimization of membrane fabrication process, reduction of preparation cost and enhancement of long-term stability.

Activated carbon adsorption is an efficient approach to the purification of industrial organic waste gases containing volatile organic compounds (VOCs). However, it is common that activated carbon adsorbed with VOCs is difficult to be completely desorbed, especially in the purification of exhaust gases containing styrene and butadiene, in which the adsorption capacity of activated carbon decreases significantly after desorption. This paper conducted a critical survey on the state-of-the-art of research on activated carbon adsorption/desorption in recent years, and then summarized the reasons for the decay of adsorption performance of activated carbon, identified the species in the heel substances, as well we discussed heel formation mechanism with aim to clarify the influencing factors. The results indicated that the adsorbed VOCs formed heel and block the pore through pyrolysis, coupling, polymerization, thermal oxidation reactions and chemisorption during the cyclic adsorption/desorption process of activated carbon. Heel may be chemisorbed species, semi-coke/coke and polymers. Factors including high adsorption temperatures, low regeneration heating rates, high purge gas flow rates, VOCs with high boiling points and large kinetic diameters and activated carbons with high microporosity may result in the heel formation; meanwhile, it was difficult to figure out the influence of desorption temperatures, oxygen impurities in desorption purge gas, molecular structure of VOCs, activated carbon surface oxygen groups and inorganic composition at present. More efficient regeneration methods, directional preparation and modification of activated carbon may be the technical ways to mitigate heel in activated carbon during VOCs purification.

In order to efficiently utilize the spent bleaching earth produced by the edible oil industry, a novel adsorbent was prepared by transforming spent bleaching earth into BE500 and BE700 to remove the copper ions (Cu²⁺) and tetracycline (TC) that commonly existed in livestock and poultry wastewater. The effects of adsorbent dosage, pH, ionic strength, and competition adsorption under the binary system was investigated. The results showed that BE700 was more suitable for Cu²⁺ adsorption, while BE500 exhibited higher removal efficiency for TC. Compared with Cu²⁺, the adsorption capacity of TC was less sensitive to the changes in the pH of the reacted solution. The results of kinetic models pointed out that the adsorption of BE500 and BE700 for Cu²⁺ and TC could be mainly attributed to the chemical reaction, and the liquid-film diffusion controlled the whole adsorption rate. The adsorption isotherms and thermodynamics model indicated that Cu²⁺ and TC were multi-layered immobilized on the surface of BE500 and BE700, and the adsorption was spontaneous with an endothermic process. In addition, the ion interference experiment showed that the co-existed of Cl^- and Na⁺ posed an insignificant role in influencing the adsorption performance for Cu²⁺ and TC. The Cu²⁺ and TC adsorption capacity of BE500 and BE700 was significantly enhanced under the binary system compared to that in the single system, which meant that the Cu²⁺ and TC presented a synergistic effect due to the reaction between Cu²⁺ and TC. The characterizations suggested that the pore-filling, ion exchange, complexation, hydrogen bond and π-π electron donor-acceptor interaction might participated in the removal mechanism of Cu²⁺ and TC.

The resource application of coal gasification fine slag is an important way to achieve the “carbon peaking and carbon neutrality” in China. In this study, the coal gasification fine slag (FS) obtained from Space Furnace was used as the catalyst carrier after simple water washing and ultrasonic impregnation to prepare CoO@FSC with well dispersion. The as-prepared catalyst was used to activate peroxide single sulfate (PMS) for the efficient degradation of wastewater containing bisphenol A (BPA). The results showed that the CoO particles were uniformly distributed on the surface of the fine slag, which avoided the accumulation of metal oxides in the actual catalytic degradation process and thus provided more active sites for activating PMS. BPA could be completely degraded within 25 minutes by CoO@FSC under the conditions of 30℃, 0.2g/L catalyst dosage, 6mmol/L PMS dosage and 50mg/L BPA concentration and the degradation could be effective a wide pH range from weak acid to alkaline substrate. The free radical quenching experiment confirmed that the main active substances in the BPA catalytic degradation process were ¹O₂ and ·O{}_{\mathrm{2}}^{-}. The good catalytic performance of CoO@FSC demonstrated the potential application of coal gasification fine slag in the degradation of organic pollutants, and provided a theoretical basis for its further utilization.

Aiming at the problems of selective iron removal from sulfuric acid cinder and cyanide tailings, the technology of iron removal and the valuable metals enrichment such as gold and silver by oxalic acid and ammonium oxalate was proposed. The species distribution diagrams of Fe(Ⅲ) and C₂O{}_{\mathrm{4}}^{\mathrm{2}-} in Fe³⁺-C₂O{}_{\mathrm{4}}^{\mathrm{2}-}-H₂O solution were drawn. The relationships between Fe(Ⅲ) species distribution and the pH, the molar concentration ratio of [C₂O{}_{\mathrm{4}}^{\mathrm{2}-}]_TOT to [Fe³⁺]_TOT and the liquid to solid ratio were analyzed. The relationship between the leaching effect of hematite and the species distribution of Fe(Ⅲ) in the leaching solution was revealed and the technologies of resource utilization of the leaching solution were also discussed. Results showed that the pH and the molar concentration ratio of [C₂O{}_{\mathrm{4}}^{\mathrm{2}-}]_TOT to [Fe³⁺]_TOT were the main factors affecting the species distribution of Fe(Ⅲ), and its species distribution in the leaching solution determined the leaching effect and the leaching time of hematite. In order to shorten the iron removal time and improve leaching effect, the molar ratio of [C₂O{}_{\mathrm{4}}^{\mathrm{2}-}]_TOT to [Fe³⁺]_TOT should be higher than 3, and the pH should be controlled near the minimum pH when the Fe(C₂O₄){}_{\mathrm{3}}^{\mathrm{3}-} distribution fraction reached 1. The iron removal technology of oxalate and ammonium oxalate had a short time and a good iron removal effect, and it was beneficial to concentrate gold, silver and metal sulfide as well as the resource utilization of the leaching solution. The research results would provide the theoretical and technical support for efficient, clean and resource utilization of these industrial solid wastes containing gold and hematite, which were produced in gold smelting industry and synthetic sulfuric acid industry.

Three protic ionic liquids (PILs) composed of the same anion of [TFSA== (CF₃SO₂)₂N^-] and different cations of N-hexylammonium (HHexam⁺), monoprotic hexylethylenediaminium (HHexen⁺) and hexyldiethylenetriaminium (HHexdien⁺), [HHexam][TFSA], [HHexen][TFSA], and [HHexdien][TFSA] were studied for the absorption of CO₂. First, the more stable configurations of the three PILs were optimized via the M06-2X/6-311G(d,p) of the density functional theory. The results indicated that the stronger N—H···N-type hydrogen bonds were formed mainly between the N-atoms in the cations and the N-atoms in the anion of the PILs. Then, the configurations of PIL-nCO₂ were optimized. The N—H···O-type weak- or moderate-strength hydrogen bonds were formed mainly between the N—H bond in the cation of the PIL and the O atoms of CO₂. The results of the vibrational frequency of the N—H bond, and the electron density and the second-order perturbation energy of N—H···O showed that a single molecule of [HHexam][TFSA], [HHexen][TFSA] and [HHexdien][TFSA] was saturated when bonded with 2,3 and 4 CO₂ molecules, respectively. Meanwhile, the results calculated by COSMOtherm software found that the Henry constants (kPa) for CO₂ in the three PILs varied as 1.91×10⁴ for [HHexam][TFSA]>1.68×10⁴ for [HHexen][TFSA]>1.51×10⁴ for [HHexdien][TFSA], indicating that the solubility of CO₂ in the PILs followed the order of [HHexdien][TFSA] with three amino groups in the polar head > [HHexen][TFSA] with two amino groups > [HHexam][TFSA] with one amino group. These results suggested that the number of amino groups in the PIL structure had a significant effect on its ability to absorb CO₂. With increasing number of amino groups in the structure of PILs, its solubilization capacity for CO₂ increased.

Recently, superwetting materials are widely used in oil-water emulsion separation, but there are few reports on the simultaneous separation of complex oil-water mixtures containing bacteria. To solve this problem, a comprehensive strategy of one-step O/W separation and efficient sterilization by photothermal conversion was proposed. Using melamine sponge (MS) as the substrate, chitosan (CS), CuS and polyvinylpyrrolidone (PVP) were loaded on MS by a simple two-step soaking method, and the prepared MS@CS-CuS@PVP composite sponge had superhydrophilic/underwater superoleophobic and photothermal antibacterial properties. The chemical structure and micromorphology of the material before and after modification were characterized, and the purification ability of the composite sponge to emulsion containing bacteria was studied. The results showed that the underwater oil contact angle of the composite sponge reaches 155.4^o with the addition of CuS nanoparticles, and it had the underwater superoleophobic property. Composite sponge was applied to the separation of oil-in-water emulsion, the separation efficiency was above 98.56%, and it had good chemical and mechanical stability. The high photothermal conversion performance and photothermal stability can promote the purification of the emulsion containing bacteria under light irradiation, which increased the separation flux by 22% and the sterilization rate by 18.84%. This would provide more inspirations for the separation of complex oil-water mixtures and provide new solutions to potential problems in industrial applications.

The FeS/chitosan-based carbon aerogel composites (FeS/CA-0.5) were prepared by sol-gel method, freeze-drying and high temperature carbonization method using chitosan as raw material. The surface morphology and structure of FeS/CA-0.5 composites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The effects of FeS/CA-0.5 on adsorption capacity of Cr(\mathrm{Ⅵ}) were studied to investigate the reaction mechanism using Cr(Ⅵ) as the target pollutant. The results showed that FeS/CA-0.5 retained the structure of chitosan-based carbon aerogel and successfully dispersed FeS with a large specific surface area. FeS/CA-0.5 was magnetic. The adsorption capacity of Cr(Ⅵ) on FeS/CA-0.5 could reach 173.84mg/g at 100mL concentration of 100mg/L solution adsorbent dosing of 0.05g, pH of 2, a reaction time of 360min. The adsorption process conformed to quasi-secondary kinetics and the Langmuir isothermal adsorption model. The in-particle diffusion model indicated that the adsorption of Cr(\mathrm{Ⅵ}) by FeS/CA-0.5 was a multi-step process and the whole adsorption process was spontaneous endothermic. The mechanism of chromium removal by FeS/CA-0.5 mainly involved physical adsorption, chemical adsorption and chemical reduction. The method of removal of Cr(Ⅵ) in wastewater by FeS/CA-0.5 had a promising application.

An efficient HCl removal adsorbent was obtained by hydrating pure calcium oxide with ethanol solution. The adsorption performance on HCl at different reaction temperatures and initial HCl concentrations was investigated in a fixed bed reactor. The experimental data were fitted and analyzed using four reaction kinetic models. The results showed that the adsorbent surface of CA-ET-33 indicated a porous and large specific surface area structure due to the covering and dynamic deposition process of the ethanol organic molecules, while greatly increasing the 2—10nm pore occupancy ratio, which promoted its adsorption of HCl. The apparent reaction kinetic models fit the experimental results in the following order from best to worst: pseudo-second-order kinetic model, Elovich model, pseudo-first-order kinetic model and intra-particle diffusion model. The pseudo-second-order kinetic model can describe the actual adsorption behavior of the adsorbent, showing the adsorption was mainly chemisorption-based. The elevation of temperature provided sufficient activation energy for chemisorption, and the rise of initial HCl concentration enhanced the driving force of the mass transfer from the gas phase to the adsorbent surface. The cumulative adsorption capacity ascended with the addition of temperature, and the increase of HCl initial concentration shortened the period to reach the equilibrium. A general kinetic equation was determined that can predict the adsorption process of HCl of a Ca-based adsorbent.

Using yellow phosphorus slag as silicon source and cetyltrimethyl ammonium bromide (CTAB) as a supporting agent, the SiO₂-based composite adsorbent (SiO₂-CTAB) was prepared and its adsorption performance for p-nitrophenol (PNP) in wastewater was studied. Effects of adsorption temperature, solution pH, adsorbent input, initial concentration of PNP and adsorption time on the adsorption performance were investigated. The adsorption kinetics, thermodynamics and adsorbent regeneration properties were analyzed, and the related substances were characterized by SEM, EDS, XPS, FTIR and other means. The results showed that the optimum adsorption conditions were temperature 20℃, pH=6 and the amount of adsorbent 1.5g/L. Under these conditions, the removal rate of 50mg/L PNP simulated wastewater can reach 96.95% and the maximum adsorption capacity of PNP was 157.2mg/g. The adsorption process of PNP by this adsorbent conformed to the pseudo-second-order kinetic model, and the Langmuir adsorption isotherm model can well describe the adsorption process.

Adsorptive separation of NF₃ from semiconductor exhaust gases has become an increasingly important topic in industrial applications. By introducing iodine ions into cage-like organic network (CON), quaternized I-CON material was prepared. The DFT calculation revealed that the electric field was formed on the pore surface by introducing iodide ions, which enhanced the inducing force between NF₃ molecule and I-CON framework. Compared with CON, the NF₃ adsorption capacity of I-CON increased from 30.49mL/g to 45.13mL/g and the IAST selectivity increased from 10.59—15.49 to 15.01—19.47 according to the single-component gas adsorption results. Moreover, the dynamic adsorption selectivity of I-CON was also higher than that of CON in the breakthrough tests. Thus, separation ability of CON could be effectively improved by ion modification, showing its potential for the real-world NF₃ capture and enrichment.

A lot of alkaline-rich ash and slag wastes which are produced from calcium carbide production has the potential to capture and then mineralize CO₂. In this paper, the purified dust removed from the flue gas of a calcium carbide furnace was viewed as the research object and the deionized water was used as leaching agent. The influences of the mineralized reaction temperature, the volume fraction of CO₂, the liquid-to-solid ratio on the pH of the leaching solution from purified dust during CO₂ absorption process and the mineralization efficiency were studied. At the same time the reaction difference between direct mineralization and indirect mineralization was compared. The experimental results showed that the initial pH of mother liquor leached by deionized water from purified dust was about 12.7. The CO₂ mineralized product of purified dust was calcite with nanoscale diameter at 25 ℃. Enhancing the reaction temperature could shorten the required time for mineralization reaction. Meanwhile, it also promoted the formation of flower-shaped aragonite CaCO₃ and its particle grew in size. The mineralization reaction time became shorten through reducing the liquid-to-solid ratio and increased the volume fraction of CO₂. The efficiency for direct mineralization was close to about 60%, which was greatly higher than indirect mineralization efficiency. But the reaction time required for direct CO₂ mineralization was much longer than that for indirect CO₂ mineralization.

In order to clarify the effect of NaCl content on the formation and stability of CO₂ hydrate, this paper used silica gel as the porous medium to form hydrate under the initial temperature and pressure of -0.5℃ and 3.3MPa, respectively, and carried out hydrate decomposition experiments under the conditions of 1.5℃ and 0MPa. The formation and decomposition rules of CO₂ hydrate in the system with different concentrations of NaCl (0.18—0.53g/L) were determined. The experimental results showed that: the induced nucleation time of CO₂ hydrate shortened with the increase of NaCl concentration, and the nucleation time was smaller than that of the pure ice powder system when the concentration was greater than 0.48g/L, but the amount of hydrate generation and the induced nucleation time showed an opposite trend with the change of NaCl concentration; NaCl was not conducive to the rapid formation of hydrate during the primary pressurization, and during the secondary pressurization, only 0.28—0.38g/L NaCl promoted the hydrate formation rate. Meanwhile, it was found that the addition of NaCl enhanced the stability of CO₂ hydrate, the stability of hydrate increased and then decreased with the increase of NaCl concentration, and the stability was best at 0.38g/L NaCl concentration.

The degradation of gemfibrozil (GEM) by UV/H₂O₂ and UV/NaClO processes was comparatively evaluated. Both advanced oxidation systems can effectively degrade GEM. Compared with UV/H₂O₂ system, the degradation rate of GEM in UV/NaClO system was faster. In UV/H₂O₂ and UV/NaClO systems, the degradation rate of the target increased with the increase of oxidant concentrations. Because pH could affect the oxidation capacity of ‧OH and the composition ratio of free radicals in UV/NaClO system, the pH of the solutions had a significant impact on both systems. When pH was increased from 5 to 11, the kobs in UV/H₂O₂ and UV/NaClO decreased from 0.2115min^-1 and 1.3115min^-1 to 0.1064min^-1 and 0.2283min^-1, respectively. Cl^- and HCO{}_{\mathrm{3}}^{-} can slightly accelerate the degradation of GEM in UV/NaClO system, but slightly slow down the degradation of GEM in UV/H₂O₂ system. HA can inhibit GEM degradation in both systems through competition and filter effect. Because the molar absorption coefficient of HClO/ClO^- was higher than H₂O₂, HA had less inhibitory effect on GEM degradation in UV/NaClO system compared with UV/H₂O₂ system. The main oxidation species degrading GEM in UV/NaClO system were ‧OH and Cl‧. The degradation path of GEM in both systems mainly included hydroxylation, demethylation, H-extraction and C—O bond breakage steps. In terms of economic benefits, UV/NaClO system was more cost-effective than UV/H₂O₂ system.

The leaching pattern of Pb, Zn, Cu, Cd, Cr, and Ni from three typical solidified/stabilized fly ash samples under variable leaching scenarios (landfill leachate invasion + acid rain corrosion, carbonation + acid rain corrosion) was investigated using multiple extraction procedure (MEP) leaching tests. The results showed that solidified fly ash with Portland cement and stabilized fly ash with chelating agent or phosphoric acid showed different degree of resistance in short-term leaching in the face of different leaching scenarios. However, from a long-term perspective, they also failed to avoid the risk of increasing the leaching level of toxic metals due to the extension of leaching time or the change of leaching scenario, especially in the face of alternative leaching scenarios. In particular, the early leaching stage with landfill leachate or CO₂-saturated water and the replacement of simulated acid rain were all unfavorable factors for increasing the leaching level of toxic metals. Moreover, the prolongation of cumulative extraction time re-increased the leaching level of most toxic metals, but the trend varied with different fly ash samples. Pb and Cd were the two toxic metals with the most frequent over their corresponding standard limits. For example, when cement solidified FA was exposed to acid rain corrosion scenarios after landfill leachate invasion and carbonation, the maximum leaching concentrations of Pb and Cd were as high as 0.36 (>0.25)mg/L and 0.28 (>0.15)mg/L, respectively. Therefore, assessing the leaching level of heavy metals according to the actual disposal scenario of fly ash is of great practical significance for characterizing the actual disposal risk of fly ash in the landfill.