Along with the depletion of fossil fuels, industrial development has brought economic benefits, but also leads to large amounts of CO₂ emissions, which has aggravated the greenhouse effect and caused the problem of global warming. Upon the advocacy of energy conservation and pollution reduction, CO₂ fixation technologies are vigorously developed in China to transform the abundant CO₂ into chemical raw materials, fuels and even higher value-added products. It can not only protect the environment but also improve economic benefits. At present, the continuous expansion of the global renewable energy scale has relieved the pressure of traditional energy consumption, while renewable energy can provide a sustainable and clean driving force for CO₂ fixation. Meanwhile, with the development of molecular biology, the bio-fixation technology of CO₂ has become more and more mature. And compared with other fixation technology, bio-fixation of CO₂ has various advantages including mild conditions, high selectivity and the diversity of products, which has gradually become the focus in this field. Herein the recent research on the coupling of biocatalysis with electrochemical and photochemical reactions for CO₂ fixation was summarized including the coupling of photocatalysis or photoelectrocatalysis with enzyme catalysis, and the combination of photocatalysis or electrocatalysis with the whole-cell catalyst technology. The principle and research progress of these strategies were introduced, while the current issues in the field as well as the essential technologies to break through the conversion efficiency of CO₂ were also prospected.

One-carbon compounds (C₁, including CO₂, CO, methane, formate and methanol) have been considered as ideal alternative feedstocks for biomanufacturing, due to their abundance and low production cost. Microbes that could use C₁ substrates has been widely studied and engineered for production of biofuels and chemicals from C₁ feedstocks. This review briefly summarized the sources of C₁ feedstocks including traditional coal, oil and natural gas, and renewable resources. Microbes that utilize C₁ compounds as energy and carbon sources, and various C₁ compounds utilization pathways in these microbes were detailed. Achievements in production of value-added products from C₁ feedstocks in various hosts, as well as challenges in this area and further efforts needed were also discussed.

Under the current increasingly severe climate and energy crisis, there is an urgent need to reduce dependence on fossil fuels and utilize cleaner and sustainable feedstocks such as one-carbon resources including methanol, formic acid and carbon dioxide. Yeast, as a eukaryotic organism, has great potential in the biotransformation of one-carbon compounds due to the existence of organelles, which can isolate the toxic substances produced during the metabolism of one-carbon compounds. Recently, with the in-depth understanding of methanol metabolism pathways and the gradual improvement of genetic manipulation tools, many advances have been made in producing chemicals from methanol using natural methylotrophic yeasts. Also, the development of commonly used industrial yeasts such as Saccharomyces cerevisiae and Yarrowia lipolytica as synthetic methylotrophic yeasts has also achieved remarkable achievements. Herein the research progress of yeast chassis in the transformation and utilization of one-carbon raw materials is focused. Further, the current bottlenecks and potential solutions for the biotransformation of one-carbon resources are analyzed. With the development of more precise and efficient tools and the interpretation of cellular metabolic networks, the biotransformation of one-carbon resources by yeasts will play an increasingly important role in the future of green biomanufacturing.

Microbial CO₂ fixation is one of the effective strategies to realize CO₂ resource utilization, which provides a reference for carbon abatement, energy-saving production and green synthesis. However, there are problems in microbial CO₂ fixation process, such as insufficient CO₂ utilization rate, high energy demand, and difficult pathway optimization. In order to solve these problems, this paper summarizes six natural CO₂ fixation pathways and five artificial CO₂ fixation pathways, and systematically analyzes the latest progress of metabolic engineering of microorganisms for CO₂ fixation from three aspects: autotrophic microorganisms, heterotrophic microorganisms and artificial microorganisms. For CO₂ fixation by autotrophic microorganisms, the main strategies include improving the efficiency of CO₂ fixation pathways, developing energy capture systems, and regulating the distribution of carbon metabolism. For CO₂ fixation by heterotrophic microorganisms, the main methods include strengthening the carboxylation pathway, remodeling the CO₂ fixation pathway, and optimizing the energy supply. For CO₂ fixation by artificial microorganisms, the main research ideas include the design of artificial CO₂ fixation pathways and the construction of artificial CO₂ fixation microorganisms. Finally, we further prospect the development direction of improving CO₂ fixation efficiency by engineering key enzymes, pathways and microorganisms.

With the ever-increasing energy demand, human society is over-reliant on traditional carbon-based fossil energy, which not only accelerates the consumption of the earth's limited energy reserves, but also leads to the continuous accumulation of carbon dioxide (CO₂) in the atmosphere. How to sustainably capture and reuse CO₂ and achieve an efficient zero-carbon network cycle has become one of the major challenges that human beings urgently need to solve. In recent years, electrocatalytic CO₂ reduction reaction (CO₂RR) production of value-added chemicals using green sustainable electricity has become a research hotspot. In this review, we firstly introduce the basic electrochemical reaction principle of CO₂RR. Then we summarize the main metal-based catalysts for the electrochemical reduction of CO₂ to prepare formic acid/formate, and focus on the design and regulation strategies of three metal-based (Bi, Sn and In) catalysts. In addition, we generalize the in situ characterization methods related to CO₂RR, including in situ spectroscopic techniques and in situ X-ray characterization technique. Finally, the future opportunities and challenges for the electrocatalytic CO₂ reduction are prospected.

The vision of attaining a carbon peak and achieving carbon neutrality guides the transition to a low-carbon economic system in China. It is a huge challenge to achieve by 2060, under the premise of continuing the high-speed economic growth, that the quantity of carbon dioxide and other greenhouse gases emitted by diverse activities such as production and living might be offset by the amount of carbon dioxide sequestered by bio-fixation-transformation and other technologies. How to balance "emission" and "absorption and utilization," as well as carry out effective emission reduction, capture and reuse of carbon dioxide to promote the achievement of carbon peaking and carbon neutrality goals, has emerged as a critical issue and pressing task for scientific study and industrial development. To date, six natural CO₂ fixation pathways have been identified, although there are problems such as poor carbon efficiency and challenging modification. With the development of electrochemical technology, the chemical conversion of carbon dioxide to formic acid has become increasingly mature in recent years. Biotransformation using formic acid as a substrate has become a popular issue in biological carbon fixation. In this review, we summarize the latest research progress in the transformation and reconstruction of formic acid biotransformation pathway, mainly emphasizing on the reducing power balancing and the construction of formic acid autotrophic strains, and also discuss the existed problems of formic acid biotransformation and its potential breakthroughs.

Syngas is a group of important raw gases from petrochemical, coal chemical and biomass processing industries. Chemical catalysis has been used for converting syngas into multiple bulk chemicals such as ammonia, olefin and methanol, but cannot achieve the production of long-chain value-added compounds from syngas with high selectivity. Biological conversion, as an effective approach to surmount the above problem, is expected to expand the syngas industry chain. In recent years, with the rapid development of molecular genetic tools and synthetic biology, strain design and modification and fermentation technologies, which are associated with syngas utilization, have been widely studied. However, the carbon fixation efficiency and product spectrum and yield of microbial syngas utilization is urgent to be improved to meet the requirements of large-scale industrialization. Here, we reviewed the latest research progresses in biological conversion of syngas and discussed the trends of future development, aiming to provide information on the development of more economically viable technologies and processes for syngas utilization.

The biological conversion of methane is a novel and potential solution in dealing with the environmental and energy challenges caused by greenhouse gas emissions. Aerobic methanotrophs are capable of utilizing their native metabolic pathways to oxidize and assimilate methane, which plays an important role in the global carbon cycle. As the development of biomanufacturing, aerobic methanotrophs have been considered as an essential platform for the biosynthesis of chemicals and fuels. At present, the energy metabolism pathway and reducing power supply of methanotrophs have been systematically evaluated and optimized by utilizing genome-scale metabolic network model, multi-omics analysis and metabolic engineering transformation. In this paper, the energy supply and metabolism characteristics of aerobic methanotrophs in substrate-level phosphorylation and oxidative phosphorylation pathways were firstly introduced, and regulation strategies between energy flow and carbon-nitrogen metabolism as well as the latest research progress were emphatically summarized and discussed. Finally, the development direction and challenges of biological energy supply of methanotrophs were prospected in terms of enhancement, tools, and strategies, which will provide profound information for the construction of efficient methanotrophic-cell factory.

Gas power plants use stable and clean fossil energy to generate electricity. The capture and resource utilization of low concentration CO₂ produced in the production process under the background of double carbon are very important for carbon neutralization. In view of the difficulty of low concentration CO₂ capture and high desorption cost, a new way to solve the problem of low concentration CO₂ capture and resource utilization is provided by using CO₂ absorbent solution to culture microalgae to produce oil. The absorbent solution with high capture capacity to CO₂ and simultaneous fast cultivation ability to microalgae is decisive factor for the design and preparation of solution. This paper summarizes the application of the existing absorbent solution, and combs out the development prospect of carbon capture of compound absorbent solution coupled with microalgae nutrition regulation. Moreover, the alkalinity and salinity of the absorbent solution are the most significant factors affecting the CO₂ assimilation by microalgae. The effects of different temperature and light conditions on the bioconversion of CO₂ by microalgae are discussed. The different effects of CO₂ gas flowing into the reactor by means of microporous bubbling and airlift diversion on CO₂ capture and microalgae growth are described. From the perspective of promoting CO₂ absorption and simultaneously producing oil by microalgae, the progress of algal species mutation, acclimatization, and genetic modification is introduced. In addition, the economic viability of absorption-microalgae method to realize carbon neutralization in gas power plant is analyzed according to case study. Compared with the traditional CO₂ absorption and microalgae fixation methods, the integrated absorption-microalgae method provide a competitive alternative for gas power plants to achieve carbon neutralization.

The performance improvement of the heat exchanger has a significant impact on the improvement of the energy efficiency of the refrigeration and heat pump systems. The circuit optimization of the finned tube heat exchanger is an important research direction of heat exchanger performance improvement because of no extra cost and easy operation. This paper summarizes optimization methods and evaluation indexes of the finned tube heat exchanger circuit. The main methods are the optimization of the wind speed distribution on the air side, the flow rate on the refrigerant side, and the pipeline structure including the pipe diameter, the pipe splitting point, and the variable circuit. Other methods are the optimization based on maximization of micro-element heat transfer, based on exergy analysis with minimum irreversible loss, minimization of entropy generation, thermal resistance balance method and genetic algorithm. It is concluded that the variable flow path can meet the optimal circuit of the evaporator and the condenser at the same time, and is the best choice for the optimization of the circuit of the cooling and heating dual-purpose refrigeration and heat pump systems. In addition, the thermal resistance balance method can optimize the circuit of the evaporator and the condenser at the same time, which is the current optimization method with good applicability. The amount of heat transfer under the same pump power and thermal resistance balance are general evaluation indexes. Based on the above analysis, prospects and suggestions are put forward for the optimization method and evaluation index of the finned tube heat exchanger.

Recently, in order to meet the huge challenges brought by the new round of industrial revolution, many manufacturing enterprises are seeking the opportunities of transformation and upgrading actively. However, it is difficult for enterprises to make a clear understanding of their current stage and final construction goals when they start to conduct the intelligent manufacturing and digital transformation. This paper proposed an intelligent manufacturing readiness model based on the characteristics of process industry production and operation to evaluate their current situation about intelligent manufacturing construction from four dimensions of business, organization, technology and intelligence. The model covered 9 evaluation categories, 25 evaluation domains and 249 characteristic item requirements, which was aimed at helping process industry enterprises to clarify the current development status, found out the short slabs and cleared the directions of construction. In addition, this paper also proposed the "readiness index" to quantify the level of intelligent manufacturing readiness, and its calculation method and evaluation process were detailed introduced to achieve self-evaluation for intelligent manufacturing readiness level. Finally, 35 process industry enterprises in Shandong province were evaluated using the new proposed model to show the application effect and value.

The purpose of the present paper is to further enhance and reasonably evaluate the comprehensive performance of the heat transfer enhancement technology of applying jet in the helical channel. The installation position of jet pipe was altered and an evaluation index of enhanced heat transfer was put forward. The heat transfer enhancement effect of jet added on the inner and outer walls of the helical channel with circular cross-section was compared experimentally and numerically. The numerical simulation results were in good agreement with the experimental results. Based on the same mass flow, the effects of jet incidence angle (α) and the ratio of jet flow rate to mainstream mass flow rate (ε_jm) on the heat transfer characteristics and flow resistance were investigated. Considering the increase of pump power caused by the jet, the comprehensive heat transfer enhancement effect of jet was compared and analyzed by using the ratio of heat and power coefficient hpc as the evaluation index. The results showed that, compared with the jet added to the outer wall, the jet added to the inner wall had stronger fluid disturbance, better heat transfer enhancement effect and less total power consumption. The studied ranges of α and ε_jm were α=30°—80° and ε_jm=0.1—1.5, respectively. The jet with ε_jm=0.5,α=60° was best in comprehensive heat transfer enhancement. The highest values of hpc was 1.39 and 1.32 for the jet added to the inner and outer wall respectively.

Chemical looping combustion (CLC), with wide fuel adaptability, can be operated with multiple fuels, including gas, liquid, and solid fuels. The CLC processes of isopropanol, sewage sludge, and coal were investigated in a 3kW tower interconnected fluidized bed reactors, in which several internal gas distributors were arranged along the fuel reactor to establish a multi-staged chambers structure. The experiments were intended to indicate the rules of reactor optimization design, oxygen carrier selection, and operational fluidization strategy as treating with differential fuels, which was also expected to promote the CLC development with the formation of strong pertinence, high carbon capture efficiency, and flexible fluidization. For the fuel with low carbonization and high organic matter content, the CLC process intensification should emphasize the improvement of gas-solid reaction and cyclone collection efficiency. The char gasification was no longer the critical factor on account that above 99% CO₂ capture efficiency was acquired in the 3kW reactor as adopting sewage sludge as fuel. The Fe-based oxygen carrier showed a limited reactivity with loading isopropanol, which would release abundant CH₄ in the pyrolysis process. The oxygen demand for isopropanol CLC was high as 10%—19%, in the unconverted CH₄ accounted for 80%. The CLC reactors should select or blend functional oxygen carriers according to the physicochemical characteristics of pyrolysis gases. The char gasification was the limited step in the coal CLC process, resulting in only 60% CO₂ capture efficiency obtained in the 3kW reactors, which had a simplified circulation structure resulting in a limited particle residence time. Coupling carbon stripper and adding an additional circulation loop of char particles were the critical factors to realizing high-efficiency chemical chain combustion. In addition, it was urgent to pay attention to the continuity and stability of solid fuel feeding. The intermittent feeding mode of the screw feeder could cause periodic and significant fluctuation of fuel reactor and feed leg pressure and destroy the stability and safety of cyclic operation.

At present, in the determination of gas adsorption performance and material design screening, the traditional experiments consume time and effort, so Grand Canonical Monte Carlo (GCMC) method in molecular mechanics has been widely used. However, the growing number of materials makes the GCMC method more and more computationally intensive, and a framework for screening adsorption materials based on machine learning (ML) method was proposed to solve this problem. The framework included three stages: the building of ML model, material selection of idealized PSA process model and validation using GCMC method. Firstly, artificial neural network models were established, and the structure descriptors "natural building unit (NBU)" of zeolite materials was proposed to predict the adsorption capacity under certain conditions. For CO₂ and N₂, two multi-layer feed-forward neural networks with different topological structures were built. Secondly, the ideal adsorbed solution theory (IAST) can predict the mixture adsorption isotherms of CO₂/N₂ (mole fractions is 0.14/0.86) from pure-component adsorption isotherms, and then 11 "best" zeolite materials were selected by some adsorbent evaluation metrics. Four zeolite materials (MON, ABW, NAB and VSV) were selected and calculate their adsorption data using GCMC method. The results proved that their adsorption capacity for N₂ was much lower than that for CO₂, so they had high adsorption selectivity for the two gases and can well separate CO₂ from binary mixtures.

Under the low-carbon policy, the efficient utilization of new energy is imperative. The core of concentrating photovoltaic technology for effective utilization of solar energy is solar cells. Solar cells are very sensitive to temperature changing. High temperature will greatly reduce the performance and service life of solar cells. Therefore, the heat dissipation of solar cells is the bottleneck restricting the development of the technology. This paper first introduces the necessity and difficulty of heat dissipation of concentrated solar cells, and then reviews the research status and latest progress of solar cells cooling technology from the perspectives of inter-wall cooling and direct-contact cooling according to whether there is a wall between solar cells and heat sink. Finally, Based on the cooling effect and solar cells performance gain of different cooling technology, the advantages, disadvantages and future research focus of cooling method are analyzed, which provides a reference for the effective heat dissipation of solar cells in concentrating photovoltaic system.

Desalination is greatly important for alleviating the global challenge of fresh water resource shortage. However, most of the traditional desalination technologies face the limitation of excessive energy consumption. The emerging solar-driven interfacial evaporation technology has attracted extensive attention in recent year owing to its low-cost, high-energy efficiency and sustainability. During solar interfacial evaporation process, the sun light can be captured by the photothermal conversion material and converted to thermal energy, which is subsequently transferred to the water molecules at interface, resulting in water evaporation and purification. In this review, we firstly summarize the evolution of solar interfacial evaporation system structure design in the past years. Then the development of emerging photothermal conversion materials including metal-based plasma materials, carbon materials, semiconductor and biomass materials in seawater desalination and waste water treatment is reviewed. Furthermore, the potential of solar interfacial evaporation technology for organic solvent purification is proposed and discussed. Lastly, the prospect and challenge of solar interfacial evaporation technology are summarized, and in particular the coupling of solar interfacial evaporation with steam power generation, photocatalysis and photodecomposition of aquatic hydrogen is pointed out.

Conversion of ethanol to other high value-added chemicals has attracted extensive attention recently, especially upgrading to higher alcohols (C₆₊) through Guerbet reaction. The research and development status of several typical heterogeneous catalysts, including hydroxyapatite (HAP), hydrotalcite (LDHs) and supported metal catalysts, for the conversion of ethanol to higher alcohols in recent years are reviewed in this paper. Their advantages and disadvantages are comprehensively compared and analyzed. The reasons for the low selectivity for higher alcohols of current catalysts are discussed based on the reaction mechanism. The design and improvement to obtain an ideal catalyst are prospected. It is pointed out that the higher alcohols selectivity could be improved by promoting the aldol reaction step in Guerbet reaction. The metal-supported catalyst can accelerate the rate-limiting step significantly. Fine regulation of metal, acid and base active sites distribution on the support surface and the controlled synthesis of catalyst with specific structures will be the focus of future research in this field.

Methyl glycolate(MG) is an important fine chemical intermediate with special functional groups, and a new biodegradable plastic of polyglycolic acid (PAG) can be synthesized by the polycondensation of MG. MG can be produced in large-scale via selective hydrogenation of dimethyl oxalate from syngas and the high-performance catalyst is the key, which however is still in the early stage of industrialization. The reaction network and reaction characteristics are analyzed in the work. Subsequently, the heterogeneous catalysts for the hydrogenation of DMO to MG is overviewed, including Cu-based catalysts, Ag-based catalysts, and other catalyst systems. The focuses and existing problems of current researches are discussed in detail, and some improvements for the MG catalysts are also suggested. This review will be a useful reference for the development of hydrogenation catalyst with independent intellectual property rights.

NH₃ selective catalytic reduction (SCR) technology has high denitration efficiency, excellent selectivity and good usefulness. It is thus the mainstream method of NO _x removal in coal-fired power plants. V₂O₅/TiO₂ catalyst is widely used due to its high denitration activity and sulfur resistance in the medium temperature range (300—450℃). However, SO₃, NH₃ and water vapor in the flue gas would produce ammonium bisulfate (ABS) and ammonium sulfate (AS). Due to the capillary condensation at low temperature, ABS would deposit on the surface of V₂O₅/TiO₂ catalyst and the activity will be reduced. In order to avoid the catalyst poisoning at low temperature, we analyzed the formation mechanism of ABS on the catalyst surface, the harm to the catalyst and the research progress of anti ABS poisoning by catalyst modification, and found that the improvement measures mainly focus on inhibiting the ABS formation and promoting its decomposition. Finally, the promotion of the anti ABS poisoning performance of SCR denitration catalyst at low temperature by reasonably adjusting the catalyst's physical structure such as wall thickness, pore diameter and isolation layer, and by adding additives such as MoO₃, BaO, Nb₂O₅, Fe₂O₃, CeO₂ and SiO₂ were summarized, which could provide some theoretical guidance for the future research in this area.

For ammonia selective catalytic reduction (NH₃-SCR), the Mn-based catalysts have good low-temperature catalytic activity, but they are susceptible to SO₂ and H₂O. Adjusting the structural and morphology of the catalysts can effectively improve their sulfur and water resistance. Therefore, this review summarizes the research progress of Mn-based catalysts with different structures of core-shell, hollow, three-dimensional ordered porous and two-dimensional layered structure, for the sulfur and water resistance. The mechanisms of sulfur and water poisoning of Mn-based catalysts are briefly described. The effect of structure on the resistance enhancement of Mn-based catalysts is also analyzed based on the combination of poisoning mechanism and structural characteristics. This review also summarizes the preparation methods of the above four structural catalysts, and points out the development direction of industrial preparation of structural catalysts in the future. At the same time, the future research work is prospected. Suggestions such as in-depth study of synergistic poisoning mechanism, optimization of catalysts formulation via simulation are put forward, which could provide reference for improving Mn-based catalysts’ resistance and industrial preparation.

Biomass catalytic pyrolysis to obtain high-value products such as bio-oil is one of the most promising methods to replace traditional fossil energy. However, there is a serious catalyst deactivation problem in the pyrolysis process, among which carbon deposition is the most important factor leading to catalyst deactivation. This paper reviews the catalyst carbon deposition in the field of biomass catalytic pyrolysis in recent years, focusing on the causes and characterization methods of catalyst carbon deposition deactivation, the analysis of the influencing factors of carbon deposition (catalyst structure, catalyst acidity and reaction temperature), the inhibition of catalyst carbon deposition (catalyst modification, high pressure reaction conditions, etc.) and coke catalyst regeneration methods (oxidative burning regeneration, ozone low-temperature regeneration, non-thermal plasma regeneration, etc.). The new microwave catalytic pyrolysis technology to inhibit and eliminate catalyst carbon deposition is intruduced. The current difficulties and development directions in this field are prospected, in order to provide a theoretical basis for the study of catalyst carbon deposits in the process of biomass catalytic pyrolysis.

Dry reforming of methane can convert two greenhouse gases (CO₂ and CH₄) into syngas, for which traditional supported catalysts suffer from the sintering of metal particles and the carbon deposition, leading to the deactivation. Core-shell structure catalysts can effectively solve the aforementioned problems due to the spatial confinement effect. In this paper, the core-shell structures are classified into three categories, SiO₂ shell layer, Al₂O₃ shell layer and other shell layers, according to the shell type. Current research status is reviewed from the aspects of preparation method, structure-morphology and catalytic characteristic, respectively. The advantages of SiO₂ shell layer are simple preparation, facile adjustment of the thickness and mesoporous structure, and high thermal stability, while Al₂O₃ shell layer can provide alkaline sites to enhance the adsorption and reaction of CO₂ and the CeO₂ shell layer can provide oxygen vacancies to promote the activation of CO₂ and the gasification of accumulated carbon. Finally, this paper proposes several future research directions for core-shell structures, i.e. the expansion and study of shell materials, the investigation of new core-shell structures such as yolk-shell and sandwiches, the precise adjustment of the morphology of core-shell structures and the study of structure-catalysis relationships, and the large-scale preparation for industrial applications.

The WO₃/BiOCl_0.7I_0.3 composite photocatalytic materials were prepared by simple calcination method and in-situ precipitation method. The microstructure and chemical composition of the synthesized materials were characterized by XRD, SEM, XPS and UV-Vis DRS. The photocatalytic performance of the WO₃/BiOCl_0.7I_0.3 composite was evaluated by the visible light catalytic degradation of 20mg/L tetracycline hydrochloride. The results showed that the WO₃/BiOCl_0.7I_0.3 composite had better photocatalytic performance than the single BiOCl_0.7I_0.3 and WO₃. When the molar ratio of W to Bi was 1∶15, the composite had the highest photodegradation rate, reaching the maximum value of 93.84% at 60 min under visible light and still had good photocatalytic activity after four cycles of test. The results of free radical capture test and electron spin resonance spectroscopy were analyzed. It was found that h⁺ and •O₂^- were identified as the main active substances in photocatalysis. The photocatalytic mechanism of Z-type heterostructure of WO₃/BiOCl_0.7I_0.3 composite was proposed. The research provided a new idea for the development of new visible light photocatalytic materials and a new way for the treatment of antibiotic wastewater.

The texture and acid properties of amorphous silica-alumina have a great impact on its hydrocracking performance. Four kinds of TiO₂-ASA were prepared by using ammonia, ammonium carbonate, sodium hydroxide/urea and sodium hydroxide respectively as precipitants. Then NiW/TiO₂-ASA hydrocracking catalysts were prepared, and their hydrocracking performance was investigated using decalin as the model compound. The TiO₂-ASA and NiW/TiO₂-ASA catalysts were characterized by XRD, N₂ adsorption-desorption, NH₃-TPD, Py-IR, and SEM. The results showed that precipitant has a great influence on the specific surface area and pore volume of TiO₂-ASA. When ammonium carbonate was used as the precipitant, TiO₂-ASA has high specific surface area and narrow pore distribution. When the precipitant was sodium hydroxide, the TiO₂-ASA with large pore volume and wide pore distribution can be prepared. The results of decalin hydrocracking showed that the NiW/TiO₂-ASA catalyst prepared with ammonium carbonate had excellent texture properties and more moderate and strong acids, the conversion of decalin was up to 52%, and the ring-opening product selectivity reached 12%.

Using carbon-based solid acid from potato starch as carbon source, and 3%(mass) Pt/C as catalyst, we explored the reaction conditions of hydrogenation of nitrobenzene to p-aminophenol. Under the optimized reaction conditions, when solid acid with acidity of 2.316mmol/g was used as acid catalyst, the conversion of nitrobenzene was 100% and the selectivity of p-aminophenol was 67.6%. The reaction mechanism of hydrogenation of nitrobenzene to p-aminophenol was summarized: ① nitrobenzene was hydrogenated on Pt/C catalyst to produce phenylhydroxylamine intermediate; ② p-aminophenol was produced by Bamberger rearrangement of phenylhydroxylamine on solid acid catalyst; ③ the main side reactions include further hydrogenation of phenylhydroxylamine to aniline, disproportionation of phenylhydroxylamine to aniline and nitrosobenzene, condensation of phenylhydroxylamine with nitrosobenzene to produce by-product azobenzene oxide. Through mechanism analysis and experimental verification, it is proposed that in order to improve the yield of p-aminophenol, the hydrogenation of nitrobenzene and the Bamberger rearrangement process should be comprehensively considered.

Using activated carbon as the catalyst carrier, we prepared three catalysts of Pd/AC, Cu/AC and Cu-Pd/AC by impregnation method. The catalysts were applied to trifluorochloroethane hydrodechlorination to prepare trifluorochloroethylene. The effect of Cu introduction on the performance of the catalysts was studied. The properties of fresh, spent, and regenerated Pd-Cu catalysts were measured using XRD, XPS, BET, H₂-TPR, TG and NH₃-TPD. The results showed that the Pd catalyst had good hydrodechlorination performance, and the main product was trifluoroethane. The addition of Cu was beneficial to improve the selectivity of chlorotrifluoroethylene. This should be related to the interaction between Cu and Pd and the formation of alloys, which inhibited the dechlorination. Surface coking, adsorption of Cl, and the change and migration of the valence state of the metal Cu were observed on the catalyst. The formation of high boiling species on surface, metal migration due to halogen adsorption, and changes in Cu-Pd interaction were the main reasons for the deactivation of Pd-Cu catalysts.

The industrial production of 1,6-hexanediol (HDO) is by the hydrogenation of dimethyl adipate (DMA). The rational design and development of the Cu-based catalysts is of great importance to improve the yield of HDO. In this work, a series of CuAl _x /SBA-15 catalysts on Al-doped mesoporous molecular sieve SBA-15 were prepared. The catalytic performance and mechanism of the catalysts were investigated, and the reaction conditions were also optimized. The results showed that the CuAl₅/SBA-15 catalyst increased the amount of Lewis acid in the catalyst matrix and improved the Cu⁺/Cu⁰ ratio, thus enhancing the selectivity of the DMA hydrogenation reaction. Besides, the doping of Al reduced the agglomeration of Cu active species, and therefore, improved the stability of the catalyst. The yield of HDO reached the maximum of 87.05% under the reaction conditions of 240℃, 6MPa, and 6h. After the CuAl₅/SBA-15 catalyst was recycled for 36h, the yield of HDO maintained at about 86.01%, implying great stability of catalyst. In summary, the results of this study provided reference for the design of Cu-based catalysts for ester hydrogenation reactions.

Silica aerogel, as the lightest solid material, is known as a new type of super thermal insulation material with the advantages of low thermal conductivity, high porosity and high specific surface area. However, silica aerogel suffers from poor mechanical performance and high cost, which significantly hamper its widespread applications in thermal insulation. This paper reviews the synthesis technologies and mechanical properties enhancement methods of silica aerogel, and their effects on the aerogel performance are analyzed from the aspects of preparation process control, aging conditions optimization, heat treatment, fiber and polymer composite. Emphasis is put on the silica aerogel's thermal insulation application in aerospace, military industry, industrial pipelines, building insulation, new energy vehicles and other fields in recent years, and analyzes the technical challenges. It is pointed out that in the future, it is necessary to further expand its operation temperature range, consider co-precursor and chemical cross-linking methods to enhance the thermal insulation performance at high temperature, and at the same time solve the problems of "powder loss" of aerogel gel fiber composite and uneven dispersion of micron powder, particularly the rapid development of emerging application fields such as new energy vehicles. The silica aerogel's synthesis technologies need to be further designed and optimized for new application requirements.

Inspired by the superwetting phenomenon in nature, three-dimensional superwetting porous materials have attracted extensive attention from scientific researchers due to their unique advantages of oil-water separation. Firstly, this paper analyzed the basic surface wetting model of three-dimensional super-wetting porous oil-water separation materials including Young model, Wenzel model and Cassie-Baxter model. Then, it was pointed out that the key to design three-dimensional superwetting porous materials was to control the surface energy and nano-microstructures of materials, and the oil-water separation principle of three-dimensional superwetting porous materials was briefly introduced. Moreover, the unique advantages of three-dimensional superwetting porous materials were summarized including high porosity, low density, light texture, large specific surface area and so on. The oil-water separation principle of the common three-dimensional superwetting porous materials was revealed that (i) the adsorption effect of surface media or groups on different oil/water droplets, and (ii) the surface selective effect on different oil/water affinities. Based on this, the research progress of different three-dimensional superwetting porous materials in the oil-water separation field was summed up including three-dimensional super-wetting porous sponge, three-dimensional super-wetting porous foam and three-dimensional super-wetting porous aerogel. The unique advantages and disadvantages of different types of three-dimensional porous materials in the oil-water separation process were summarized and pointed out the problems and challenges of three-dimensional superwetting porous materials in practical oil-water separation application. Finally, the development of three-dimensional superwetting porous materials with stable mechanical properties, good resilience and lasting separation affect was prospected.

Perfluoropolyether (PFPE) polymers possess low surface energy, low friction coefficient, excellent lubricating properties and good hydrophobic-oleophobic properties. They are widely used as lubricating materials of the fields of aerospace, nuclear industry, vacuum equipment, electronics, etc. They are also used as reactive intermediates of the synthesis of many functional composites. Recently, PFPE-based functional composites have received extensive attention in several emerging fields. Firstly, the latest research progress of PFPE polymers in the lubrication field are introduced. The insufficiencies of corrosion resistance, anti-rust, and the PFPE base oils creep-resistant of PFPE lubricants are mainly expounded, and their reasons are analyzed. Then, the research progress and application prospect of PFPE polymers in the aspects of functional coatings, fluorine-containing polyurethanes, fluoroelastomers, and Vitrimers are summarized. Preparation processes of some fluorinated functional composites are introduced. Finally, the future trends on research and application of PFPE polymers are prospected in order to provide new ideas for widening the application field of PFPE polymers and developing high value-added PFPE derivatives.

In view of the problems of difficult dispersion with emulsification and ion crosslinking of polypropylene wax phase change materials, the low degree of polymerization polyacrylic acid (PAA) grafted polypropylene wax was designed by taking advantage of the hydrophilic and easily ionized properties of polyacrylic acid (PAA) carboxyl group. The polypropylene wax emulsion was prepared by self-emulsification method. Polypropylene wax solid-solid phase change materials (PPW SS-PCMs) were prepared in aqueous medium in a short period. Firstly, the effects of acrylic acid concentration and instantaneous concentration on the self-emulsification ability of PP wax (PPW) graft products were investigated by means of infrared spectrometer, nuclear magnetic resonance spectrometer and scanning electron microscope. Then, the crystallization properties and thermal stability of PPW SS-PCMs and PPW SS-PCMs were tested and analyzed by polarizing microscope, X-ray diffrotometer, differential scanning calorimeter and thermogravimetric analyzer. The results show that the enthalpy of phase change materials decreases with the increase of acrylic acil (AA) content as the mass ratio of AA increases. In a certain range, the self-emulsification ability of modified PPW can be improved by increasing the instantaneous concentration of AA, and the amount of fixed components can be reduced. When the mass ratio of AA∶ PPW∶BPO was 0.36∶1∶0.05 and the drop acceleration rate was 9mL/min, the crystallization temperature, enthalpy and energy storage efficiency of the prepared PPW SS-pcms were 52.46℃, 53.61J/g, 81.26%, and has good thermal stability.

Two-dimensional materials have a unique layered structure and stable physical and chemical properties. Recently, two-dimensional membranes composed of layered two-dimensional materials have shown the extraordinary potential application of membrane separation. Here, La³⁺ ions were intercalated into the MoS₂ membrane during the membrane formation by mixing MoS₂ nanosheets and La³⁺ solution. The atomic force microscope and X-ray photoelectron spectroscopy were used to confirm the structure and composition of the MoS₂ lamella. The structure and interlamellar spacing of the La³⁺-MoS₂ membrane were studied by scanning electron microscopy and X-ray diffraction spectroscopy. The permeability of the membranes was investigated by pressured filtration device and forward osmosis device. The results showed that the La³⁺ ions were successfully intercalated into the MoS₂ membranes, resulting in the high-water flux of the La³⁺-MoS₂ membrane. The pure water flux of the La³⁺-MoS₂ membrane was 18.5 times higher than that of the blank MoS₂ membrane. The La³⁺-MoS₂ membrane indicated a remarkable sieving effect for dyes with molecular weight from 400 to 800g/mol based on the steric hindrance effect. Moreover, the Na⁺, K⁺, Mg²⁺ and Ca²⁺ ions were rejected by the La³⁺-MoS₂ membrane due to the Donnan effect. In the repeatability experiment, the Na⁺ rejection rate of La³⁺-MoS₂ membrane can still be maintained at more than 95%, showing good repeatability and stability. The results provided a new method for the modification strategy of MoS₂ membrane and the treatment of printing and dyeing wastewater.

Lignocellulosic biomass is abundant which has been proved to be a promising renewable resource in energy, chemical and pharmaceutical, etc. The efficient hydrolysis and utilization of lignocellulose are limited by the existence of hydrogen bond and covalent bond between its components, which require complicated pretreatment methods, such as acid, alkali, high temperature, organic solvent and enzymatic hydrolysis to overcome. The main component of lignocellulosic hydrolysates is the mixture of hexose (60%—70%, mainly glucose) and pentose (30%—40%, mainly xylose). Aiming at the utilization efficiency of xylose and glucose in the hydrolysates, this paper reviewed xylose and glucose co-fermentation in genetically engineered microorganisms for the production of alcohol, biolipids, γ-PGA and organic acids, and described the the research progress in reconstruction of metabolic pathways, regulations of gene level and fermentation technology optimization. Finally, the main characteristics of recent research, technical bottlenecks and future research directions in this field were summarized from the perspectives of strain screening, gene and metabolic engineering regulation, immobilization of cells, product treatment and fermentation process, in order to obtain more research methods and ideas.

Different components have different freezing points. Melt crystallization utilizes the difference of freezing point to separate and purify the target components from the melt mixture through crystallization, washing and sweating on the basis of management of the energy flow. Due to the advantages of no solvent, low energy consumption, compact equipment and high pure product, melt crystallization is widely used in the field of separation and purification of organic compounds. The classification of melt crystallization are introduced firstly. Then the patterns of melt crystallizers are sketched. Besides, the research progress on separation and purification of organic isomers, organic chemical materials, daily necessities, food and medicine by melt crystallization is reviewed systematically. Furthermore, the existing problems in separation and purification of organic compounds by melt crystallization are analyzed. Finally, the development trends of separation and purification of organic compounds by melt crystallization are discussed. With the development of melt crystallization, the separation and purification of organic compounds by hybrid melt crystallization technologies aiming at raising product quality, decreasing energy consumption, and saving money, has been the main trend. The system engineering which contains melt crystallizers, processes, nucleation kinetics, growth kinetics, sweating mechanisms, and heat and mass transfer model will be the research hotspot of separation and purification of organic compounds by melt crystallization.

With the increasing demand for high performance fracturing proppant, the advanced chemical theory and technology of oilfield chemistry have been applied to carry out a series of effective fracturing proppant chemical coating modification and products, contributing to the rapid development of the oil and gas industry. From the perspective of chemistry and engineering, this paper systematically reviews the recent advances on chemical coating modification of fracturing proppant. In a view of chemistry, the research directions mainly include: chemical coating on the proppant surface, chemical methods to change the surface properties of proppants, and combination chemical coating and modification. From an engineering point of view, it can be roughly divided into three important research directions: ① to improve the strength of proppant by coating the surface of proppant, such as quartz sand and ceramsite; ② to reduce the relative density of the proppant by coating the surface of the proppant, such as self-suspending coating technology, etc; and ③ to achieve the function of blocking water and oil by coating the surface of the proppant with a film. The main characteristics of resin-coated proppants, hydrophobic proppants, hydrophobic and oil-repellent proppants, self-suspending proppants, self-aggregulating proppant, inorganic polymer-coated proppants and functional proppants are also briefly described. The current trends of proppants are also outlined. It is expected that proppants should be developed in the direction of multi-function, high performance, small size and intelligence, and more suitable for anhydrous fracturing and in-situ generation self-supporting fracturing systems.

In this work, with the application of one-pot synthesis based on Michael addition and temperature-programmed reaction, a series of h-PAMAM samples were successfully synthesized through adjusting the ratio of methyl acrylate(MA) to initiator. Moreover, the application of digital technology made the quality of product more reliable. The effects of demulsifier concentration, temperature and settling time on the performance of demulsifier were systematically investigated. Meanwhile, the research of interfacial tension, the real-time size and transmittance changes of oil droplets in the demulsification were also explored to analyze its demulsification mechanism. The results indicated that the oil removal rate could reach 95% with condition of 40mg/L, 30min and 60℃. Compared with commercial demulsifiers, h-PAMAM exhibited high interfacial activity and short settling time because of the unique hyperbranched multipoint structures, amido and amine groups.

To recycle the valuable by-product of the oil refining industry, ultrasonic assisted technology was used to produce fatty acids in one step from the soapstock. The goal was to test the acidification hydrolysis of soapstock by the ultrasonic assisted technology, and to explore the influence of process conditions with ultrasonic assistance. The acid value and yield of the product were taken as the inspection targets, and the influence of ultrasonic assistance on the product distribution was explored. Experimental results indicated that the acid value and yield of fatty acids were improved because of the enhanced dispersion and stirring of ultrasound. In order to determine the optimal reaction conditions, the effects of each factor on the acid value and yield of the product through single factor and orthogonal design experiments were discussed. Results showed that with formic acid as the catalyst, under the conditions of reaction temperature 220℃, reaction time 110min, ultrasonic power 1050W and ultrasonic duration 7s, the highest acid value and yield of the product were 184mg KOH/g and 79.9%, respectively. The order of factors affecting the yield of product from primary to secondary were reaction temperature, ultrasonic duration, ultrasonic power, and reaction time. The GC-MS analysis showed that the fatty acid content in the product reached 97.4%. The results of product quality index test showed that the product had high quality with saponification value 190mg KOH/g, iodine value 157g I/100g, and unsaponifiable matter content 0.54%.

Catalytic oxidation is one of the most effective water treatment technology to remove refractory organic pollutants, which has strong oxidation capacity and high mineralization efficiency, and the application and research of catalysts are the hotspots. Natural mineral catalysts have incomparable advantages over other catalysts owing to their abundant reserves and low price. In this paper, the mechanism and research progress of natural mineral catalysts in the treatment of refractory organic pollutants in wastewater by Fenton, catalytic ozonation and activated persulfate catalytic oxidation are reviewed. The corresponding reaction conditions, treatment results and catalytic active sites were analyzed. Natural minerals rich in metal elements and thus can be used as catalysts for Fenton oxidation and persulfate oxidation, some natural minerals can be used as metal carriers to participate in oxidation reactions, and natural minerals with active sites such as surface hydroxyl groups can be catalysts for Fenton oxidation and ozone oxidation. Furthermore, natural mineral catalysts can significantly increase the oxidation capacity of ROCs by Fenton, ozone and persulfate, having a promising application prospect in wastewater treatment. This review hopes to provide useful reference for the development of natural mineral catalysts and the future application in advanced oxidation technology for water treatment.

Global climate change is currently one of the serious problems facing the world. Excessive emission of greenhouse gases such as CO₂ is the main cause of global warming. Carbon capture, utilization and storage (CCUS) is a necessary means to solve global warming. Chemical solvent absorption based on organic amine has become a key technology path for CO₂ capture in coal-fired and gas-fired power plants due to its high capture efficiency and good adaptability of flue gas. This paper introduces the basic principle and process flow of amine method of CO₂ capture technology, analyzes the development of new absorbent, optimization of energy saving technology and other key means to reduce the renewable energy consumption and cost of amine method of CO₂ capture technology. Combined with the research status and the demand for amine method of CO₂ capture from flue gas, its future development trend is prospected.

UiO-66-based metal-organic frameworks (MOFs) is widely used in the field of pollutant adsorption and degradation due to its high specific surface area, developed pore structure, excellent structural stability and semiconduction-like properties. The main mechanisms responsible for organic pollutants adsorption by UiO-66-based materials from liquid phase included: physical adsorption, electrostatic interaction, hydrogen bonding and π-π interaction. Meanwhile, organic pollutants adsorption from liquid phase can be adsorbed selectively owing to electrostatic attractions and properties of different organic pollutants. However, the pollutants adsorption from gas phase mainly depended on hydrogen bond and pore structure of absorbent, while vapour can also influence significantly on pollutants adsorption. For photocatalysis, pure UiO-66-based materials exhibit poor photocatalytic activity due to the low efficiency to generate excited charges and transfer photoinduced carriers. Compounding with semiconductors to form heterogeneous photocatalysts provides a way to enhance the separated efficiency of photogenerated carriers. Moreover, the semiconductors uniformly distributed on the surface of UiO-66 are beneficial to the contact between active sites and pollutants, thus promoting the photocatalytic activity of absorbents. Meanwhile, the deficiencies of UiO-66-based materials in the adsorption and photocatalysis were also summarized. Finally, the prospects of UiO-66-based catalytic is proposed, which might provide a positive role in promoting the application of UiO-66 based materials in the study of gas/liquid organic pollutants.

The submerged powdered activated carbon-aerobic membrane bioreactors (PAC-AMBRs) are new wastewater treatment technology, which integrates PAC adsorption, microbial degradation, and membrane separation. This review focuses on the previously published research on the mechanism of directly adding PAC to the submerged PAC-AMBRs system to alleviate membrane fouling in the past 20 years. The membrane fouling mitigation mechanism of sludge flocs and dissolved organic matters by PAC is analyzed comprehensively. The effects of PAC dosage and replenishment rate on membrane fouling are discussed. It is concluded that the fouling mitigation by PAC is a comprehensive process. The cake layer formed by sludge flocs with PAC as a carrier had a loose structure and strong pressure resistance. It not only effectively reduces the cake resistance but also is used as a self-forming dynamic membrane, intercepting dissolves organic matter and suspends microorganisms and reducing membrane fouling. Dissolved organic matter is removed through the synergistic effect of PAC adsorption and/or microbial degradation on PAC, reducing membrane fouling and improving permeate flux. Regular discharge and supplement of a certain amount of PAC can improve the efficiency of fouling alleviation.

Bacterial-algal consortium can not only remove pollutants such as nitrogen, phosphorus, heavy metals and antibiotics from wastewaters efficiently, but also can capture and fix carbon dioxide, which gains increasing attention. This review provides fundamental insights into the major mechanisms underpinning antibiotics removal by bacterial-algal consortium, including biodegradation, biosorption and bioaccumulation, and biodegradation is the main way removing antibiotics from wastewaters. The existing types of bioreactor systems for degrading antibiotics are introduced, which can be mainly divided into suspended growth systems and immobilized growth systems. Finally, the review highlights the short-term and long-term responses of bacterial-algal consortia to antibiotic stress. The short-term tolerance is demonstrated mainly through the production of reactive oxygen species (ROS) and the activation of the SOS response, while the long-term resistance is manifested in the enrichment and transfer of antibiotic resistance genes and the succession and evolution of microbial community. This review provides theoretical basis and technical reference for applications of bacterial-algal consortia to remove antibiotic pollutants from wastewaters.

The HPF method will produce extremely hazardous desulfurization waste salt. In this paper, the new technology proposed included copper sulfate precipitation of thiocyanate, oxidation of thiosulfate by micro-nano bubbles, and simultaneous ammonia production by forced precipitation of sulfate by lime surface renewal as a starting point to avoid the drawbacks of long process flow and low product yield of the traditional salt extraction method. Optimization of reaction conditions for the new technology by formulating simulated desulfurization waste salt. Experiments showed that when the molar ratio of [Cu²⁺]∶[SCN^-] was 1.2, the temperature was 40℃, and the initial waste solution thiocyanate concentration was greater than 300g/L, the best removal rate of SCN^- was 99.20% after 80min of reaction. When the pH=1, the temperature was 50℃, the initial waste solution thiosulfate concentration was 50g/L, and the reaction was 420min, the removal efficiency of S₂O{}_{\mathrm{3}}^{\mathrm{2}-} was 95.18%. When the molar ratio of [Ca²⁺]∶[SO{}_{\mathrm{4}}^{\mathrm{2}-}] was 1.5, the reaction temperature was 20℃, the initial sulfate concentration of the waste solution was 500g/L, and 5g of 5mm diameter PP balls were added as grinding media, the SO{}_{\mathrm{4}}^{\mathrm{2}-} removal rate was 91.11% after 240min.

Processes such as hydrometallurgy and ternary precursor preparation will produce high-salt wastewater containing sodium sulfate and ammonium sulfate. It is of great significance to study the crystallization kinetics of ammonium sulfate in high-salt wastewater and investigate the influence of common metal ions for the treatment of high-salt wastewater. Taking the crystallization process of ammonium sulfate in a mixed solution containing sodium sulfate and ammonium sulfate as an example, the crystallization kinetics of ammonium sulfate and the influence of ferrum, aluminum, manganese and chromium on the crystallization of ammonium sulfate were systematically investigated. The results of the crystallization kinetics of ammonium sulfate in the mixed solution containing sodium sulfate and ammonium sulfate showed that the nucleation rate and growth rate equations of ammonium sulfate were: B=\mathrm{1.303}\times {\mathrm{10}}^{-\mathrm{16}}{G}^{\mathrm{1.069}}{M}_{\mathrm{T}}^{\mathrm{1.801}} and G=\mathrm{15.708}{\sigma }^{\mathrm{1.387}}. In the mixed system of sodium sulfate and ammonium sulfate, the supersaturation of the solution affected the nucleation and growth rate of ammonium sulfate. With the decrease of saturation, the nucleation and growth rate of crystals would decrease. Compared with the results of single-system ammonium sulfate crystallization kinetics, the kinetic parameters all decreased. The research results of the effect of ferrum, aluminum, manganese and chromium on the crystallization of ammonium sulfate indicated that ferrum and aluminum inhibited the growth of ammonium sulfate crystal planes and reduced the crystal size, while manganese and chromium can promote the crystallization of ammonium sulfate and increase the crystal size. Metal ions changed the crystal habit of ammonium sulfate. Manganese made the crystal appear triangular prism, while ferrum and aluminum made the ammonium sulfate crystal grow in flakes. The kinetic equations of crystallization under the conditions of different metal ions showed that ferrum and aluminum had more significant effects on the crystallization nucleation process, while manganese and chromium can promote the growth process of ammonium sulfate.

Laccases are members of the multi-copper oxidases, which are able to catalyze the oxidation of polyamines and polyphenols under ambient conditions. It is also considered as green catalyst in water treatment and soil remediation. Nanozymes, defined as nanomaterials with enzyme-like activity, have attracted extensive interest, because of their versatility, low cost and high stability. In this paper, the isocyanate ions in the hydrolysis of urea were used as template and reacted with Cu(NO₃)₂ solution to prepare hierarchical copper hydroxyl nitrate (H-Cu₂(OH)₃NO₃) with laccase-like activity. Its catalytic activity was 1.85 times higher than that of copper hydroxyl nitrate prepared by urea hydrolysis of Cu(NO₃)₂ and its v_max was 1.27 times higher than that of laccase. It also displayed high stability under various pH, high temperature, long-term storage and high salinity. It remained 58% of catalytic activity after 12 cycles. These results indicated good catalytic stability and reusability of H-Cu₂(OH)₃NO₃. Compared with laccase, H-Cu₂(OH)₃NO₃ nanozyme showed equal or even higher catalytic performance for the degradation of common phenolic pollutants in soil and groundwater, such as 2,4-dichlorophenol, hydroquinone, 2,6-dimethoxyphenol and o-aminophenol. In addition, the possible catalytic mechanism of H-Cu₂(OH)₃NO₃ nanozyme was proposed by control experiments and theoretical analysis.

Aiming at the water quality of complex composition and low chemical oxygen demand (COD) in rare earth tailings wastewater, the anammox immobilized fillers were used for treatment. First, the adaptation and domestication of the anammox immobilized fillers were carried out, and then the nitrogen removal performance of the anammox immobilized fillers alone and the anammox immobilized fillers coupled with denitrification immobilized fillers in the treatment of rare earth tailings wastewater were respectively explored. The results showed that, the anammox immobilized fillers had good adaptability to rare earth tailings wastewater. After the adaptation and domestication by adopting the stepped substrate and shortening hydraulic retention time (HRT) operation strategy, the total nitrogen removal load rate (NRR) of the anammox immobilized fillers could reach up to 0.99kg N/(m³·d), which was 8.39 times higher than that before adaptation and domestication. The results of high-throughput sequencing showed that the relative abundance of the anammox dominant genus (Candidatus Kuenenia) increased from 5.53% to 35.67%, which achieved effective enrichment, while the dominant genus (CandidatusBrocadia) before adaptation and domestication were not adapted to the environment and were eliminated. When the concentration of ammonia nitrogen in the raw water fluctuated, the NRR of the anammox immobilized fillers alone for treating rare earth tailings wastewater could reach up to 1.02kg N/(m³·d), the average concentration of effluent ammonia nitrogen was 3.98mg/L, the removal rate of ammonia nitrogen and nitrite nitrogen reached 94.43%, and 60% of organic carbon sources were saved. By controlling the C/N ratio to 1.5∶1, the coupling of the anammox and denitrification immobilized fillers was successfully achieved, and the activity of the anammox immobilized fillers was not significantly affected. The average concentration of total nitrogen in the effluent was 0.65mg/L, the average removal rate of total nitrogen was 95.6%, and 84% of organic carbon sources were saved theoretically.

The bis-(2-ethylhexyl) phosphate (P204)-sulfonated kerosene extraction system was used to enrich iron ions from cyanide tailings slurry electrolyte with high sulfuric acid. The effects of P204 concentration, ratio (O/A), oscillation time, oscillation frequency and temperature on the extraction rate of Fe³⁺ and its extraction process were mainly studied. The research showed that under the conditions of P204 concentration of 25%, temperature of 25℃, O/A=1∶1, oscillation time of 10min and oscillation frequency of 180r/min, the single-stage extraction rate of Fe³⁺ in the electrolyte can reach 97.73%. The saturated extraction capacity can reach 21.57g/L. The extraction and enrichment of Fe³⁺ in the organic phase was mainly attributed to the cation exchange reaction with the hydroxyl group in the molecular structure of P204 and the coordination reaction of the phosphoryl group. The complexes formed were FeSO₄A(HA)₃ and FeA₃(HA)₃. Under the conditions of oxalic acid 1mol/L, O/A=1∶1, oscillation time 10min and oscillation frequency 190r/min, the single-stage stripping rate of Fe³⁺ in the loaded organic phase can reach more than 82.64%. The iron in the stripping solution mainly existed in the form of [Fe(C₂O₄)₃]^3-, Fe(C₂O₄)⁺, Fe(C₂O₄)₂^- and FeSO₄(C₂O₄)^-. The concentration of Zn²⁺ was only 0.628mg/L and no Cu²⁺ was detected. The organic phase still had good extraction performance after stripping.

Phenol is a typical organic pollutant in coal gasification wastewater, and its treatment has received wide attention and research. Two phenol efficient degradation strains, named JHFS-1 and QHFS-1, were screened from coking wastewater and gasification wastewater by continuous domestication and plate scribing method. The effects of temperature, pH, shaking bed speed, bacterial inoculum, Cu²⁺ and Mn²⁺ on the phenol degradation were investigated by microbial degradation experiments of phenol solution, and the microbial degradation effect of gas scrubber water produced by simulated coal gasification was also investigated. Both strains were identified as Acinetobacter calcoaceticus by 16S rDNA gene sequencing and microbiological identification. The optimized degradation conditions for phenol were 30℃, pH was 6.0, shaking bed speed was 120r/min and inoculum was 13%, and the phenol degradation rate could reach 94.31% after 24h treatment. Cu²⁺ had a certain inhibitory effect on the degradation of phenol by JHFS-1, and Mn²⁺ promoted the degradation of phenol by JHFS-1 to a certain extent. The phenol degradation by microorganisms followed the hydroxylation pathway and carboxylation pathway. JHFS-1 bacteria could effectively degrade the organic pollutants in gas washing water, and the TOC degradation rate reached 58.43%.

Aiming at the treatment of high concentration of oil and oily sludge in coal chemical wastewater, the inorganic composites materials with high charge and low degree of polymerization and organic composites materials with low charge and high degree of polymerization were prepared in this study. The coalescence separation effect of oily sludge and the removal characteristics of organic matters were investigated under the synergistic effect of organic and inorganic composite materials. The results indicated that the removal efficiencies of oil and SS in coal chemical wastewater could reach 55% and 98%, respectively, with the ratio of inorganic and organic composite materials at 500∶1. The field tests showed that the removal efficiencies of oil and SS were stable at 50% and 95%, respectively, by inorganic and organic composite materials for raw wastewater with oil of 1700—2000mg/L and SS of 1500—2000mg/L. The further researches showed that the composite material also had a good capacity for removal of various organic substances from wastewater, and the removal efficiencies of 82.85%, 41.9% and 37.56%, respectively, for PAHs, benzene series and phenolic substances had been achieved. It could be found that the inorganic and organic composite materials could effectively solve the problem of oil and oily sludge removal in coal chemical wastewater, and having broad prospects in industrial application.

In order to further explore new and efficient composite wet dust removal technology, the experimental research on the synergistic dust removal performance of surfactant droplets combined with metal mesh grid was carried out. Based on the theories of surfactant-enhanced wetting, spray dust prevention, and water-film separator, a novel test device for dust removal was constructed. Further-more, AES, LAB-35 and X-100 were selected for the experiment by testing the surface tension. The influence of air velocity, spray pressure, mesh number, number of layers and inlet dust concentration on the efficiency of dust removal was investigated in detail. The research results showed that with the increase of wind speed, the dust removal efficiency firstly increased and then slowly decreased, and the dust removal efficiency reached peak value when the wind speed was 0.8m/s. Increasing the number of layers, mesh number and spray pressure could raise the dust removal efficiency while the system resistance or water consumption increased, therefore, a comprehensive balance needed to be considered. Similarly, with the increase of the inlet dust concentration, the dust removal efficiency first increased and then decreased. When the dust concentration was 400mg/m³, the maximum dust removal efficiency was up to 96.74%. Among the three surface active droplets, 0.4% LAB-35 droplets had the highest dust removal efficiency, followed by 0.4% AES drop-lets and 0.4% X-100 droplets. In summary, the surfactant droplets had better synergistic effect than the pure water droplets combined with the metal mesh grid for dust removal, which has significant reference value for the design of new wet dust removal equipment.

A summary of National Natural Science Foundation of China (NSFC)'s fund applications, grants and funding rates in 2022 was provided based on the discipline of chemical engineering & industrial chemistry (B08). The fund applications and grants for the 16 secondary application codes of B08 were outlined, and the data for a series of funded key programs were specified, giving insights into fund applications in the next year.