The catalytic hydrogenation of carbon dioxide (CO₂) to chemicals, such as methanol, is a promising carbon capture, utilization and storage (CCUS) technology. The key challenge of CO₂ hydrogenation is the development of efficient catalyst. Compared with traditional copper based catalysts, indium based catalysts have attracted much attention due to their high methanol selectivity and excellent high-temperature stability. And thus, In based catalysts have been paid more attention in recent years since they show high methanol selectivity and good stability at high temperature. However, the understanding of the mechanism and nature of In based catalysts for CO₂ hydrogenation has not yet formed a unified theory. This review summarizes the research progress of catalyst from preparation methods, reaction mechanism, thermodynamic analysis and structure characterization. In view of the existing problems such as low single-pass conversion and insufficient catalyst stability, future research directions are proposed, including introducing extra promoters or active components, designing catalysts with special structures and coupling molecular sieves.

The concentration of CO₂ in the atmosphere is increasing year by year, and high value utilization of CO₂ is an important path to reduce the carbon emissions. Low-carbon olefins are important chemical raw materials, and CO₂ as a carbon source hydrogenation to olefins (CTO) is one of the most promising CO₂ utilization technologies that can potentially mitigate the global greenhouse gas emission and reduce the dependence of chemical production on fossil fuels. The Fe-based catalysts are recognized as a promising candidate in CTO due to their low cost and excellent performance. However, the selectivity to lower olefins and the activity of the Fe-based catalysts currently haven’t met the industrial requirements, and the mechanism of CTO reaction remains unclear. This article reviews the research progress of the iron-based catalysts for CTO reaction, including the reaction thermodynamic analysis, theoretical model, catalyst design and development (the influence of additives and supports on the structure and performance of catalysts), reaction mechanism, structure-activity relationship, and deactivation mechanism. Future research direction of catalysis was put forward. With the help of Operando technology, the dynamic structure evolution of active phases could be focused during the reaction process, and the mechanism of the catalytic material surface and interface caused by external factors could be explored. Based on the principle, which could provide ideas for the rational design of industrial catalysts.

Lower olefins are important chemical raw materials and the direct synthesis of lower olefins from syngas is a new non-petroleum route. This article first introduces two routes of synthesis gas catalytic conversion to olefins: the coupling route and the Fischer-Tropsch route. Then the thermodynamics of the CO hydrogenation reaction was analyzed. The research progress of the catalysts for direct synthesis of low-carbon olefins from syngas and the reaction mechanism of CO hydrogenation are reviewed mainly from the aspects of active phase, size effect, promoters, and metal support interactions. As an outlook, we believe that the reaction mechanism still needs to be further clarified through basic researches, and the catalyst development should focus on the precise control of O/P and product’s chain length. In terms of the industrialization, it is necessary to take into account the difference between the real reaction environment in plant and laboratory reactions, and to pay attention to the compatibility with both upstream and downstream.

Compared to other treatment methods, Fenton technology is an effective method for the degradation of non-biodegradable organic pollutants in water due to the generated highly oxidative hydroxyl radicals(·OH). However, the application of traditional homogeneous Fenton reaction is limited by its narrow pH response range, difficult recovery and separation of the active components of the catalyst, and easily generated iron sludge that will cause secondary pollution. In recent years, the heterogeneous reaction, which can effectively overcome the above drawbacks and has good industrial application prospects, has attracted extensive attention and research. This article mainly summarizes the development of Fenton technology, especially for the heterogeneous ones from the aspects of reaction mechanism, influence of reaction parameters, and materials. The emphasis is given on the advances in heterogeneous catalysts particularly for the Fe-based ones, Fe-free metal ones, carbon-based ones with introduction of their synthesis method, structure-performance analysis, plausible reaction pathways and catalytic performance for organic degradation. Finally, the influence of catalysts stability, utilization of hydrogen peroxide and rate-limit step in the heterogeneous Fenton catalyst system are summarized, which provides ideas for further improving the rational design and fabrication method of heterogeneous Fenton catalysts.

Aiming at the characteristics of multi-stream flow heat transfer, complex fin structure optimization, multiple channel configuration matching, and cryogenic engineering application, this study summarizes several problems in the thermal design of multi-stream plate-fin heat exchanger (MPHE), such as heat transfer matching, layer pattern, multi-physical field superposition, and special cryogenic operating condition. In the layer structure design and optimization, the heat-transfer flow characteristics and related performance evaluation methods of the fins are summarized to provide guidance for the structural selection. The current research hotspots and development directions of plate-fin heat exchangers are discussed according to the present situations. The results show that MPHE has great advantages in large-scale air separation and petrochemical industries, which can significantly improve the operation efficiency through increasing the gas liquefaction rate and reducing the actual energy consumption. Therefore, the local heat exchange network and multi-stream matching should be combined with the fin structure design and layer algorithm optimization using the multi-field simulation and experimental research to overcome the design problems occurred in practice. This comprehensive and efficient optimization design method can be formed to get rid of the limitations of traditional empirical design.

On the basis of self-designed and built pipeline system of drag reduction on water annulus transportation of heavy oil, the flow resistance characteristics of heavy oil simulated by 500^# white oil under the action of water ring in horizontal pipe were experimentally studied. The influence of 0.3—1.0m/s oil superficial velocities, 0.11—0.72m/s water superficial velocities and 0.13—0.49input water volume fractions on the flow patterns characteristics and drag reduction effect of water lubricated pipe flow was analyzed. The experimental results showed that the oil-water two-phase flow exhibits a typical eccentric annular flow pattern, where the annular water film can effectively isolate and lubricate the interface of oil phase and pipe wall. The pressure drop in the process of pipeline transportation can be substantially reduced by the water ring transportation, which is only 1/55—1/27 of the pressure drop when the oil is delivered separately under the same oil flow rate. The oil transportation efficiency was in a high level, which was all above 40, when input water fraction is in the range of 0.13—0.27. With the increase of oil superficial velocity and water input fraction, the pressure drop per unit pipe length increases, while the drag reduction effect and oil delivery efficiency of water annulus conveying decrease.

The Rayleigh convection and mass transfer process caused by the dissolved CO₂ is critical for the CO₂ capture and storage in the saline aquifers. In order to understand the mixing law and the effect of salt concentration on the process more intuitively, lattice Boltzmann method (LBM) was used to simulate the process. By establishing a double distribution model including density distribution function and concentration distribution function, and the external force terms such as electrostatic force and volume force were introduced into the collision equation and balance distribution function. The change of concentration field in the process of saline water absorbing CO₂ with multiple CO₂ diffusion sources at 293.15K and 101kPa was successfully simulated. The results showed that the structure of Rayleigh convection, the start time of convection, the velocity of flow field and the order of magnitude of instantaneous mass transfer flux were consistent with the previous research results. The Rayleigh convection structure can greatly promote the mass transfer rate of CO₂ absorption in saline water and the instantaneous mass transfer flux increases in the beginning and then decreases with time, which corresponds to the generation, development and stability of Rayleigh convection structure. Simulated dissolution process of CO₂ in different salt concentration solutions also showed that the increase of salt concentration will delay the start time of Rayleigh convection and reduce mass transfer rate, which is consistent with experimental results. The simulation results can also provide guidance for the storage process of CO₂ in different saline aquifers.

In view of the retrofit of heat exchange network (HEN), a retrofit idea of using utility heat to realize the concept of multi-energy complementation is proposed, which means by fully utilizing low temperature waste heat in the thermal process fluid, the retrofit of heat integration system is completed. This paper is based on the reference point non-dominated sorting genetic algorithm (NSGA-Ⅲ), through comprehensive evaluation of annual retrofit cost, annual retrofit profit, energy consumption (including heat exchange network cooling / heating utilities and waste heat system cooling water and power consumption) and beneficial output of waste heat systems of the heat integrated system considering waste heat recovery (WHR), so as to obtain optimal solution. In the case study, the retrofit of crude oil distillation system (10H5C) shows that by weighing the four goals of energy consumption, output of the WHR system, retrofit cost and retrofit profit of the integrated system, NSGA-Ⅲ algorithm is used to solve the multi-dimensional retrofit plan. Compared to basic network, it not only can provide users with a retrofit plan that saves a maximum of 22.9% of energy consumption, but also can provide a solution with a maximum output of WHR system of 4.003×10⁴kW, and can also provide a minimum retrofit. It can also develop a retrofit plan with a minimum retrofit cost of 1.848×10⁶USD/a, as well as a solution with a maximum retrofit profit and a minimum return on investment of 1.173×10⁷USD/a and 121%, respectively. Finally, by comparing retrofit performance of the integrated WHR system with HEN alone, the practicability and feasibility of the integrated WHR system, and the important role of waste heat recovery multi-energy complementary technology in improving the energy utilization efficiency of process industry energy integration system are demonstrated.

As a new cold storage medium, CO₂ hydrate has a good application prospect. In the cold storage system, the amount of CO₂ hydrate generation has a direct impact on the amount of cold storage, but the calculation of the amount of CO₂ hydrate generation is complicated, which leads to the calculation of the amount of cold storage in the system is also complicated. Therefore, it is of practical significance to establish a model that can quickly analyze and predict the amount of hydrate production in the system. In this paper, BP neural network model (BP) and grey relational prediction model [GRM(1,n)] which can solve complex problems were introduced, and GRM(1,n)-BP neural network combination model was established by Matlab programming language to predict hydrate production. Three models were selected to predict the data of the experimental system, and the results of the three models were compared with the experimental results. The results showed that the GRM(1,n)-BP neural network combination model has better accuracy and stability. Finally, the accuracy of the GRM(1,n)-BP neural network combination model by investigating the influence of the single variable of charging pressure on hydrate production and comparing the predicted results of the model was further verified.

In order to establish the complex relationship between the particle cutoff size and the full dimensions and operation parameters of cyclone separator accurately, a BP neural network (BPNN) model was develop based on data-driven for particle cutoff size. The global dimensional analysis was used, where the annular Reynolds number, the dimensionless number characterizing the impact of cyclone body dimensions, and vortex finder dimension ratio were proposed as network inputs, while the dimensionless dimension which characterized the aerodynamic equivalent particle cutoff size was adopted as network output. The influences on the training algorithm and the number of hidden neurons on model accuracy were determined, respectively. The results showed that the Bayesian regularization algorithm was superior to the L-M algorithm and the quasi-newton algorithm. The optimal prediction performance was achieved when the number of hidden layer neurons is 7. Compared with theoretical model, semi-empirical model and multiple regression model, the Bayesian regularization BPNN particle cutoff size model showed better prediction ability and generalization performance, with the mean square error of the model 0.136 and the coefficient of determination 0.975.

The bubble formation and detachment behaviors on the surface layer of packed particles were studied experimentally. The effects of nozzle diameter, packed bed height and particle size on the bubble detachment diameter and the formation period were revealed by using the high-speed camera technology. The differences of bubble formation and detachment behaviors on the surface layer of packed bed and the nozzle were analyzed. The results showed that the initial shape of the bubble generated on the surface of packed bed with the particle size in the range of 1500—3000μm was relatively flat and small, and the evolution of bubble to flat shape was faster. The effect of intake flow rate on the bubble shape was weakened with the increase of particle size. And the increase of nozzle diameter and packed bed height could effectively promote the growth of bubble detachment diameter, but delayed the formation and detachment of bubble and increased the bubble formation period. The effect of particle size on the bubble formation period diminished gradually with the increase of intake flow rate. There was a significant difference between the bubble formation and detachment behaviors on the surface of packed bed and the nozzle. In contrast, the packed bed with the particle size in the range of 150—300μm had a more obvious hindering effect on the formation and detachment of bubble, and the detachment diameter and the formation period of bubble were relatively large.

Hydrogen powered fuel cell vehicles (FCV) can solve the environmental pollution and energy consumption problems caused by traditional internal combustion engine vehicles. The purity of hydrogen fuel, especially the presence of some trace impurities in hydrogen, will affect the catalysts performance and service life of the fuel cell. The corresponding limits for 13 kinds of gas impurities content were specified by the international and national standards of ISO 14687-2、SAE J2719 and GB/T 37244 for FCV hydrogen sources to ensure a long-term good operation of fuel cell. In order to systematically understand and evaluate the various technical standard methods for analyzing important trace impurities in hydrogen for rational application in hydrogen analysis, in this review, the existing analytical technical standards and corresponding methods of the 13 gaseous impurities other than particulate matter were comprehensively integrated, and the requirements of each method and measurement were also analyzed. The working principles, advantages and disadvantages of each analytical technique and its practical research progress were expounded overall. In view of the current problems on impurities analysis in hydrogen, including primary off-line technology, low integration and poor implementability, an integrated method for simultaneous analysis of a variety of key impurities need to be designed independently, a complete analysis and monitoring system satisfying the quality assurance of hydrogen for FCV should be constructed, and it will be mainly developed in the direction of online analysis technology in the future.

The types and contents of impurities in hydrogen have an important impact on the performance and the life of the key equipment in hydrogen stations, the hydrogen supply system for hydrogen fuel cell vehicles and the core components of fuel cell. The International Organization for Standardization (ISO) and the standardization organizations of many countries have built fairly complete hydrogen quality standards for fuel cell with reasonable requirements based on the technological development trends and the industrialization process characteristics, which provides basis for the development of hydrogen energy and fuel cell vehicle technology. This paper reviews the development of hydrogen quality standards for proton exchange membrane fuel cell. Though comparing and analyzing the differences between domestic and foreign standards, we concluded that the quality standards in China are consistent with the international advanced standards. The implementation and application of the standards should be paid more attention by our country’s industry. In order to lead or participate in the formulation and revision of international standards, the collection of a large amount of test data is necessary.

Hydrogen is an ideal clean energy and an important chemical raw material. However, the current hydrogen production technology mostly uses fossil fuels as raw materials, and the hydrogen production process has the disadvantages of high energy consumption and high pollution, which also greatly reduces the cleanliness of hydrogen energy. With the development of social economy and the acceleration of urbanization, the output of municipal solid waste (MSW) increases year by year, and most of the organic matter in MSW has the potential to become a raw material for hydrogen production. Hydrogen production using organic solid waste as a raw material has dual meanings for the clean development of hydrogen energy and the resource utilization of solid waste. In this study, the research progresses of raw material pretreatment, technical routes, catalysts, adsorbents, technical and economic analysis, life cycle assessment and ecological risk assessment in the field of hydrogen production by organic solid waste thermochemical conversion are reviewed. Large-scale pilot projects and industrial demonstration projects are focused in this study. By analyzing the advantages and disadvantages of various technical routes, it can be concluded that the large-scale utilization of the new thermochemical conversion hydrogen production technology is slow due to the limitations of cost and equipment. In the field of traditional thermochemical conversion hydrogen production, the gasification of organic solid waste has the largest potential for large-scale application. According to the development status of hydrogen production from organic solid waste, the research directions of catalysts and adsorbents in this field, as well as the hot topics of technical and economic analysis and life cycle assessment are also discussed in this study. The prospects of hydrogen production from organic solid waste are given out in the end.

In the past few decades, research on hydrates has not only focused on inhibiting the formation of natural gas hydrates. Utilization technologies based on hydrate formation have also been extensively studied. Hydrate-based utilization technology is a new environmentally-friendly and sustainable technology. It can be used for gas separation and replacement by taking advantage of the differences in the equilibrium conditions. Due to high storage capacity, it can be used for gas storage. With high latent heat, it can be used for cold storage. The current status of application of hydrate technology was summarized, and the promising research directions of hydrate technology in the fields of gas separation and storage, solution concentration, cold storage, and replacement was analyzed. However, the slow hydration reaction rate, high generation pressure, and difficulty in separation at a later stage have greatly limited the industrial application of hydrate utilization technology. The future research and development directions of hydrate technology were prospected, including the development of safe, efficient and environmentally-friendly hydrate promoters, the development of high-efficiency hydrate reaction equipment, the development of continuous hydrate processes, and the conduct of a large number of pilot experiments.

The technology of hydrothermal conversion of biomass has the characteristics of good adaptability to feedstock, low cost, and high conversion efficiency, which has a great potential for industrial production of biocrude and chemicals to substitute for fossil fuels. In this paper, the updated research progress of continuous biomasses hydrothermal conversion systems was reviewed. The hydrothermal reactor, as one of the main production links, is the unique one that has achieved a continuous reaction and other links such as feeding and separation have not been achieved yet. It shows that the future production mode should be characterized by high production efficiency, low energy consumption, and environment-friendly, then the commercialization of hydrothermal conversion of biomass could be achieved. To promote the commercialization, a complete continuous system of hydrothermal conversion of biomass is proposed, which could realize complete continuous operation for feedstock pretreatment, feeding/pumping, hydrothermal reaction, and product separation. Meanwhile, this system could realize heat exchange by recycling aqueous products, and higher thermal efficiency and energy saving could be achieved through the process of primary product separation. Furthermore, the discharge of process water would be more eco-friendly through heat recovery and reuse of the aqueous products. Based on the analysis of the R&D progress to the key components in the system, this study provides an enlightenment for the further commercialization of the system.

In order to analyze the reliability of Aspen HYSYS software simulation and further determine the applicability of HYSYS software in the amine decarbonization regeneration process, based on the independently designed amine decarbonization experimental device, the corresponding HYSYS software steady-state simulation model is established. Simulation and error calculation are carried out on the amine desorption rate and regeneration energy consumption under different acid gas content, amine liquid flow, amine liquid formula, regeneration pressure and regeneration temperature, and the applicability of HYSYS software in amine decarbonization regeneration process is analyzed. The research results show that using the HYSYS software to simulate the regeneration process in the amine decarbonization process, the variation of the simulation results with the process parameters is generally consistent with the test results. Except for some process parameters that are not conducive to regeneration, the simulation applicability of the HYSYS software is good. Among the five process parameters in HYSYS software that affect the regeneration effect, the regeneration pressure has a greatest impact on the simulation applicability, while the two different formulations of MDEA+MEA and TEA+MEA have the least effect In addition, the regeneration temperature has a great influence on the simulation error of the regeneration energy consumption. At a certain bottom pressure, the regeneration temperature has a turning point. Above this temperature, the regeneration energy consumption increases significantly. During the verification process, the regeneration temperature is around 115℃, which is a turning point, but the overall simulation energy consumption adaptability of HYSYS software is poor.

Settling aids method is one of the most used approaches to remove solid particles from catalytic cracking slurry. Focus on the shortcomings of exiting slurry settling aids, an amino-terminated block polyether, which combined amine groups that provided hydrogen bonds and acid-base pairs with block polyether that provided bridging action, was prepared and determined by liquid nuclear magnetic spectrum. The comparative experiments showed that the amine group and block polyether played a synergistic role, and the linkage promoted the dispersion of amine groups in the oil slurry. In order to facilitate industrial applications, the amino-terminated block polyether was compounded with solvent oil and glycol to prepare the resultant settling aids with different contents. Through the investigation of the dosage, settling temperature and settling time, the optimum process conditions were determined as follows: the settling aids with 40% amino-terminated block polyether contained was added into oil slurry with a dosage of 400mg/kg and kept at 90℃ for 48h. With this process, the deash efficiency can be more than 90% and the residual ash in the upper slurry can be less than 0.02%, which can be used to prepare high-value products, such as advanced carbon black. For this high effective settling aids, the raw materials is easy to obtained, thus it has a great potential for industrial production and applications.

The tar pitch needed to be pretreated to remove the solid particles (called quinoline insoluble, QI) to obtain refined pitch as a precursor for the preparation of various functional carbon materials. Effect of pressure on the removal of QI in coal tar pitch and mixed pitch with biomass pitch by the solvent method was investigated. The QI content and yield of refined pitch under different pressures were tested. Nanometer particle size analyzer, SEM and high temperature viscometer were used to determine the morphology and particle size of QI particles and the viscosity of the system during the process of refining pitch. The results indicate that pressure has a slight effect on the QI content of refined pitch and a significant impact on the increase in refined pitch yield. The yield of refined coal tar pitch increases from 64.6%(mass fraction) at 0.1MPa to 84.3%(mass fraction) at 1MPa, and the QI content of refined pitch is maintained between 0.06%—0.1%(mass fraction). With the addition of 15% biomass tar pitch, the yield increases from 55.7%(mass fraction) at 0.1MPa to 72.5%(mass fraction) at 1MPa. Increasing of pressure is beneficial for the solubility of the solvent, especially for the dissolution of heavy components. Higher pressure also increases the viscosity of the medium, which makes it difficult for some QI particles to settle, but the effect is small. The refined pitches are used to prepare mesophase pitches with flow domain-like texture. Adding biomass pitch can better improve the flow domain-like microstructure.

This study combined U-tube solar collector and phase change materials (paraffin wax) to fabricate an experimental platform for comparative investigation on water production and heat storage performance. The experimental results represent that the application of paraffin wax could effectively increase water production by 462g and working duration by 0.5h. At given test conditions, the thermal efficiency of U-tube solar collectors integrated with paraffin wax could reach approximately 54.6% and 28.51% in summer and transition season, respectively. In addition, the enhancement ratio of useful heat decreases from 38.26% to 14.66% in summer and 38.67% to 13.85% in transition season with an increase in the flow rate of the working medium. The findings suggest that the flow rate should be considered to optimize the application of U-tube solar collector integrated with paraffin wax in a practical project.

As an industrially important raw material and synthetic intermediate, aniline can be directly prepared by catalytic reduction of nitrobenzene. More and more attention has been paid to the application of porous carbon materials in catalysis due to their high specific surface area, well-developed pore structure and recyclability. However, the application of porous carbon materials directly as catalyst is limited by their inadequate active sites and chemical inertness. Heteroatomic doping can enhance the surface polarity, adjust the electronic structure and improve the catalytic performance of the porous carbon materials. Therefore, the doped porous carbon materials can be used as effective catalysts for the reduction of nitrobenzene. This review summarizes the recent research progress of doped porous carbon materials in the catalytic reduction of nitrobenzene. The preparation methods for the nitrogen-doped and co-doped porous carbon materials, as well as the doped porous carbon materials loading noble and non-noble metals are presented. Special attention is given to the catalytic performance, possible catalytic active sites and the catalytic mechanism of the doped porous carbon materials. Finally, the problems of reaction selectivity, catalytic activity and production cost are still needed to be solved in the reduction of nitrobenzene catalyzed by doped porous carbon materials. Using biomass as the precursor to develop co-doped porous carbon materials and doped porous carbon materials loading bimetals is one of the important directions in the future.

The rapid development of the pharmaceutical industry in China brought economic growth and convenience to life, as well as large volatile organic pollutants (VOCs) emission. Among various VOCs purification methods, catalytic combustion is considered as a good one with favorable environmental friendliness and flexibility for purifying pharmaceutical VOCs which is characterized by the large emission, multiple emission nodes, and complex types of pollutants. In this paper, typical volatile organic compounds emitted from the pharmaceutical industry and the characteristics of these pollutants were summarized. Based on this, the development and application of catalytic materials in the catalytic combustion of pharmaceutical VOCs in recent years were further summarized. Meanwhile, the prospect of organic waste gas treatment in China’s pharmaceutical industry was proposed. Firstly, more in-depth researches such as pharmaceutical VOCs emission characterization and laboratory scale VOCs purification should be performed to ensure the economic effectiveness in the actual purification process. Secondly, new process coupling multi-technology should be developed to improve the purification efficiency to meet the pharmaceutical industry exhaust emission standards in China.

Biomass is the unique renewable organic carbon resource with abundant reserves in nature. Through the reaction processes in the presence of a catalyst, it can be converted into high value-added carbon-based chemicals and fuels. Biomass has been considered as an ideal substitute for traditional fossil resources. The development of catalyst material plays the key roles in utilization of biomass resources. Ionic liquids (ILs), known as designable materials, have been widely applied in this field. In view of the catalytic performance of metal ions and the designability of ILs, the introduction of metal sites into IL’s structure to prepare the metal-based ILs catalysts has attracted widespread attention in the field of biomass utilization. Herein, based on the above background, this paper aimed to review the recent progress in the catalytic conversion of biomass under the metal-based ILs catalysts by focusing on the catalytic conversion of biomass-based carbohydrates and lignin into platform chemicals, and the catalytic (trans-) esterification of oleic acid or oil to prepare biodiesel in the presence of metal chloride-ILs and polyoxometalate-ILs, respectively. Meanwhile, the catalytic conversion of other biomass by the metal chelate-ILs and ILs metal salt was also reviewed. In addition, the application of metal-based ILs in biomass utilization field were summarized and prospected, and some suggestions were given to guide the design of metal-based ILs catalysts. Hopefully, it would be helpful in development and utilization of biomass resources.

According to the “Minamata Convention” and environmental protection policy, the development of mercury-free catalysts for acetylene hydrochlorination is indispensable and exigent in China. Among all kinds of mercury-free catalysts including noble metal, non-noble metal and non-metallic catalysts, noble metal catalyst is considered to be the most promising catalyst for industrial application. The research progress of Au, Ru, Pd and Pt based catalysts for acetylene hydrochlorination in recent years was reviewed, with the emphasis on the active components, catalyst mechanism and modification methods of different catalysts. The effects of different modification methods and the research direction of each catalyst were also analyzed. The use of promoters, ligands and ionic liquids, as well as the modification of supports, can improve the activity and stability of catalysts, and increase their industrial application possibility.

With the increasing shortage of fossil energy, the utilization of clean and renewable biomass resources, especially the preparation of high-quality biofuels has become a research hotspot. 2,5-Dimethylfuran (DMF) is regarded as one of the most promising liquid biofuels due to its excellent physical and chemical properties. DMF can be synthesized by selective hydrogenolysis of 5-hydroxymethylfurfural (HMF). However, HMF is chemically active and can be converted into various downstream products, so it is critical to develop catalysts with high selectivity for DMF production. In this review, recent advances of noble and non-noble metal-based catalysts are reviewed in detail for the hydrogenolysis of HMF to DMF. The limitations and problems in current researches, potential research trends of the catalysts and reaction systems were proposed. In addition, it is pointed out that the direct preparation of DMF from biomass and the establishment of effective separation technology are important for realizing the industrial production of DMF.

The hydrogenation of polycyclic aromatic hydrocarbons can be inhibited by the adsorption and activation of their final aromatic ring, which is attributed to the increased resonance energy, steric hindrance and competitive adsorption among saturated products. In this work, the characteristics of hydrogenation process and hydrogenation catalysts were reviewed. The analysis indicated that the adsorption and activation process was closely related to the properties of the molecules and the catalysts. Moreover, tuning the electronic state of the active metal could promote the adsorption and activation of polycyclic aromatic hydrocarbons effectively. Meanwhile, the methods of adjusting active phase structure, increasing the number of active sites and modifying the active metal electron density of several hydrogenation saturated catalysts were also described in detail. It was concluded that improving the dispersion of active component and forming the electron-deficient state of active metals were beneficial to the further improvement of the hydrogenation activity of the catalysts, which could be effectively realized by adjusting the support's acidity and introducing additives.

Low-dimensional black phosphorus plays an indispensable role in the field of photocatalytic degradation due to its numerous advantages, such as directly adjustable bandgap structure, high carrier mobility, and good biocompatibility, etc. However, it is sensitively oxidized under the ambient environment and electron-hole pairs are rapidly recombined, leading to low utilization rate. Therefore, to prepare the stable and efficient low-dimensional black phosphorus composites is significant for its practical applications. In this paper, the preparation of low-dimensional black phosphorus and the application of its composite in the photodegradation field were reviewed. The exfoliation effects and changes in optical properties of low-dimensional black phosphorus prepared via different methods were compared. Mechanical exfoliate methods, chemical vapor deposition methods, liquid exfoliate methods, and solvent thermal synthesis methods were described in detail. The composite materials of carbon, metal, semiconductor, and other materials as well as composites prepared by low-dimensional black phosphorus were summarized. The activities of the composites in the field of photodegradation and the optical changes of low-dimensional black phosphor composites were analyzed. The problems existing in the preparation of low-dimensional black phosphorus and its composites were presented. Through the different preparation methods of composites described in this paper, its practical applications were put forward.

For controlling the emission of NO with ambient temperature and high O₂ content, the typical selective catalytic reduction (SCR) technology is not suitable anymore. The catalytic oxidation of NO over carbon-based active materials at ambient temperature has gained much attention. Through this technology, NO can be oxidized to NO₂ at ambient temperature and high O₂ content, and recycled in the form of nitric acid or nitrate. Due to the great environmental and economic benefits, this technology has a broad application prospect. In this paper, research progress of carbon-based active materials for catalytic oxidation of NO at room temperature. The mechanism of NO catalytic oxidation wasdescribed. The effects of surface physicochemical characteristics and reaction conditions of carbon-based materials (O₂ concentration, NO concentration, GHSV, reaction temperature, water vapor and catalyst particle size, etc.) on the catalytic oxidation of NO, as well as the catalytic characteristics of different carbon-based materials such as activated carbon, activated carbon fibers, carbon nanofibers, carbon xerogels, metal-supported carbon based active materials, and carbonized sludge were introduced. The future trend for catalytic oxidation of NO at low temperature was summarized and prospected.

In order to effectively improve the catalytic activity and separation of activated carbon in microwave field, magnetic Fe₃O₄/activated carbon(Fe₃O₄/AC) catalyst was prepared by chemical coprecipitation method, which was then used for the catalytic oxidation degradation of dimethyl phthalate(DMP) in aqueous solution under microwave radiation. The microstructures, morphology and magnetic properties of the catalysts were characterized by BET, SEM/EDS, XRD, XPS, FTIR and VSM. The effects of different reaction systems on the rate and kinetics of DMP degradation were studied. The effects of the amount of catalyst, the power of microwave radiation and the initial pH of the solution on the microwave-induced oxidation degradation of DMP with Fe₃O₄/AC were discussed. The reusability of Fe₃O₄/AC was also investigated. The results showed that Fe₃O₄ was the main iron oxide in the prepared catalysts, and was successfully loaded on the activated carbon. The saturation magnetization of superparamagnetic Fe₃O₄/AC could reach 21.2emu/g, and it could be quickly separated from the solution by external magnetic field. The degradation rates of DMP in the microwave-induced catalytic oxidation systems were higher than those with adsorption alone and microwave irradiation alone, and the degradation processes all followed the first-order reaction kinetics. The degradation rates of DMP could be enhanced with the increase of the dosage of Fe₃O₄/AC, the power of microwave radiation, and the initial pH of the solution. Repeated experiments showed that Fe₃O₄/AC had an excellent catalytic stability and reusability, and the degradation rate of DMP remained at 83.5% after 5cycles. It is concluded by GC-MS analysis that the degradation of DMP could be achieved by 5 pathways: hydrolysis, isomerization, hydroxylation, benzene ring trisubstitution and ring opening mineralization.

The CuZnAl-LDO composite catalysts with different Cu/Zn ratios were prepared by using the deposition-precipitation method and layered CuAl-LDH as the carrier. The ICP, XRD, H₂-TPR, N₂O-chemisorption, N₂ sorption isotherms, TEM and XPS analyses were performed to characterize the textural properties of the precursors and the catalysts. The results showed that the special layered structure of hydrotalcite with large specific surface area and abundant pore structure promoted the dispersion of Cu species and increased the interaction between Cu and ZnO, which were conducive to the adsorption of CO and H₂ on the catalyst surface and hence increased the catalytic activity. In the topological transformation of hydrotalcite precursor, the rough surface formed by the removal of lamellar hydroxyl and water confined the loaded Cu active species and inhibited their the migration and agglomeration. The space-time yield of methanol for Cu_0.6Zn_0.3Al_0.1-LDO reached 883mg/g/h, and decreased by just 2.8% after 120h. The deactivation rate of the present catalyst decreased by 81% as that of the catalyst prepared by the co-precipitation method, suggesting its excellent catalytic activity and stability.

NiMo/Al₂O₃ catalysts modified by phosphorus addition in different manners were prepared by step impregnation method. The effect of these catalysts on the performance of thiophene hydrodesulfurization (HDS) in coke oven gas was investigated on a fixed bed microreactor. The catalysts were characterized by BET, XRD, H₂-TPR, NH₃-TPD, C₄H₄S(H₂)-TPD, XPS, HRTEM and Raman. The results showed that the HDS performance of the NiMo/Al₂O₃ catalysts was greatly different. The weak adsorption dissociation on the activity sites of the catalysts of PNi-Mo/Al and PMo-Ni/Al was enhanced, and the catalysts had better low temperature HDS activity. When the simulated coke oven gas containing 292.5mg/m³ thiophene was used as raw material, the desulfurization rate of thiophene by PNi-Mo/Al at 250℃ was more than 61%. For PNi-Mo/Al and PMo-Ni/Al catalysts, the first impregnation of P and Ni or P and Mo made P preferentially interact with Al₂O₃, and weakened the interactions between Ni or Mo with the support of the active metal component but not too much so that the Ni or Mo could evenly disperse on the surface of the support, and hence NiMoO₄ were generated which can promote the formation of type Ⅱ active phase Ni-Mo-S by the sulfidation of Ni in the catalyst. The synergistic effect between NiMoO₄ and MoO₃ increased the sulfidation of the catalyst, resulting in the increased HDS activity.

The aluminum oxide supported ruthenium catalysts were prepared by impregnation and polyol method (i.e., Ru/Al₂O₃-IMP and Ru/Al₂O₃-CRP), and their performance in the hydrogenation of 2-ethylanthraquinone (2-eAQ) was investigated. It was found that the catalysts prepared by different methods were all active and the Ru/Al₂O₃-CRP catalyst exhibited relatively high catalytic activity and stability. The catalysts were characterized by inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoelectron spectroscopy (XPS). The XRD and TEM results suggested that Ru particles were highly dispersed on the surface of the support. In addition, the Ru/Al₂O₃-CRP catalyst exhibited a low electron cloud density of Ru according to the XPS results, which made the Ru active sites more attractive to the lone pair electrons on the oxygen of 2-eAQ, and hence was conducive to activation of 2-eAQ.

Using tin tetrachloride pentahydrate, ethylene glycol and ammonia as raw materials, tin oxide nanoparticles were rapidly synthesized under microwave-assisted hydrothermal conditions. Urea was used as a precursor to obtain g-C₃N₄ in a muffle furnace. Hydrocarbon-synthesized carbon quantum dots were prepared from citric acid and ethylenediamine, and finally stirred in a fume hood to obtain carbon quantum dot-loaded carbon nitride/tin oxide composites. TEM, X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm (BET), ultraviolet-visible spectrophotometer (UV-vis) and electron spin (paramagnetic) resonance spectrometer (ESR) were used to characterize the morphology, structural characteristics, absorbance of the composite and characterization and analysis of active substances in the process of photocatalysis. The photocatalytic performance of the samples was tested by degrading rhodamine B (RhB) under ultraviolet light. The experimental results found the red shift of the absorption edge of the ultraviolet-visible spectroscopic spectrum, indicating that the loaded carbon quantum dots can improve the response of the composite in the visible light region. The photocatalytic experiments showed that the loaded carbon quantum dots can improve the photocatalysis of the g-C₃N₄/SnO₂ composite performance. When the load of carbon quantum dots was 7%, the degradation efficiency of composites was the highest and the degradation efficiency of RhB under 3h was 97%. In addition, the microwave-assisted hydrothermal method can synthesize a large amount of tin oxide nanoparticles in a short time and the tin oxide nanoparticles had a small grain size (8.5nm), which can be efficiently prepared and applied in the field of environmental protection.

Iron oxides nanoparticles could efficiently remove a variety of organic and inorganic pollutants from water, but its practical application in water treatment is limited by the problems of aggregation, deactivation and loss. As a new category of porous materials, biochar (BC) is characterized by a large surface area, stable carbon matrix and wide availability of the necessary feedstock with low-cost, which makes it a good candidate as supporter to load iron oxides nanoparticles. Biochar supported iron oxides composites (iron oxides/BC) exhibits a great potential in decontamination of water, and has recently attracted significant scientific interests. In this work, the preparation methods of iron oxides/BC as well as the application, mechanism and influencing factors of adsorption, catalytic oxidation to remove phosphorus, organic pollutants, heavy metals and arsenic in water were mainly introduced and summarized. In addition, its application in sludge dewatering, photocatalytic disinfection was also introduced. Furthermore, future research emphasis and direction of iron oxides/BC, in terms of further improving contaminants removal performance, economic and technical feasibility of practical application, and expanding the application field of the materials, were suggested.

Mesoporous carbon spheres integrate the advantages of carbon materials with spherical colloids, including excellent fluidity, dispersity, conductivity and the controllability of their particle sizes and pore sizes, making them able to be applied in biology, catalysis, adsorption and electrochemistry. Recently, hydrothermal/soft-templating method, as a promising way to prepare mesoporous carbon spheres, is widely reported. The spherical morphology and mesoporous structure can be controlled through hydrothermal carbonization and soft template, respectively. This review presented the preparation of mesoporous carbon spheres and the control of its pore size and particle size by using hydrothermal carbonization and soft template together. Moreover, the modification and application of mesoporous carbon spheres were covered. The selection of carbon precursor, soft template and solvent were also summarized, and the perspectives of its research directions on various applications were proposed.

Inspired by the concept of green chemistry, the biodegradable membrane materials have drawn widespread attentions, and are expected to be alternatives for conventional membrane materials. In this paper, the current status and problems of traditional non-degradable membrane materials were analyzed, several popular biodegradable membrane materials were reviewed, and the applications and the limitations of the biodegradable membrane materials were discussed. Subsequently, the biodegradation mechanism of the biodegradable membrane material was also analyzed, and the biodegradability of the membrane material was explained from the molecular structure. This would help to analyze the essence of the biodegradation of the membrane material, and balance the stability and biodegradability of the membrane material. Finally, the existing challenges and a forward-looking perspective of biodegradable membrane materials were also discussed. With the deepening of research, the biodegradable membrane materials would have broad prospects and far-reaching practical significance.

Desiccant coated heat exchangers (DCHE) overcome the negative impact of released heat of adsorption during water vapor adsorption. It can also make use of low-grade heat sources, such as solar energy and industrial waste heat, and thus higher dehumidification performance and energy saving potential can be achieved. The dehumidification performance of DCHE based systems is determined by the characteristics of coated desiccants. Compared with conventional desiccants like silica gels and zeolites, hygroscopic polymers have a great advantage in water uptake. Meanwhile, these hygroscopic polymer-based composites fabricated by doping silica gels or inorganic salts have better water adsorption abilities. Recently, more and more scholars have studied the performance of hygroscopic polymers in DCHE based systems at home and abroad. In this paper, hygroscopic polymers were divided into two categories, namely natural and synthetic. The latter mainly included polymer electrolytes, metal-organic frameworks (MOFs) and polymer-based composites. Their dehumidification performance in DCHE based systems was analyzed and summarized. Binders used in DCHE based systems were also summed up. Finally, future development of hygroscopic polymers and binders was prospected.

The novel composite adsorbents were synthesized by different contents of graphene (MLG) and 13X/LiCl. The microscopic morphology and pore characteristics of the composite adsorbents were characterized by SEM and N₂ adsorption. The water vapor adsorption and desorption performances of the composite adsorbents in open environment were tested, and the effect of the amount of graphene added on the adsorption and desorption performances of the composite adsorbent was explored. Under the condition of 80% RH high humidity, 13X/LiCl with 18.4% salt content was selected as the best adsorbent (MZ) and served as the matrix for the synthesis of composite adsorbents. The experimental results showed that graphene increased the textural parameters (specific surface area, pore volume and pore size) of composite adsorbents. Except for 12G-MZ, the textural parameters of the composite adsorbents increased with the increase of graphene content. The composite adsorbents exhibited excellent water vapor adsorption performance. The relative adsorption capacity of all composite adsorbents was higher than MZ (0.554g/g). 3G-MZ had the best adsorption performance, and its water vapor adsorption capacity was as high as 0.587g/g, 2.7 times of 13X. In addition to 12G-MZ, as the graphene increased, the water vapor desorption ratio increased. The desorption ratio of 9G-MZ was close to 90%, which was 9.7% higher than MZ (81.8%). This experiment can provide basic research data for the usage of composite adsorbents in adsorption harvesting water from atmospheric air.

Crystallization mechanism and morphology control is a critical concern for the crystal engineering study and relevant application. For example, urate crystallization is important for the study of gout induced by hyperuricemia. Herein, using PP membrane as a base membrane, 8 kinds of hydrogel composite membranes (HCMs) with different polymer composition were prepared by ultraviolet cross-linking method, and PEGDA-NIPAM hydrogel materials with excellent interface induced crystallization performance were selected for continuous optimization. Based on the comprehensive analysis of the reproducibility of the hydrogel preparation process and the results of NaCl droplet evaporation experiments, PEGDA-NIPAM (molar ratio is 2∶1) material was used to prepare hydrogel slices (HGS). This type of HGS had a uniform surface, vertical structure and thickness, and the slice quality can be quantified by the surface area. Studies on the NaCl salt dissolution adsorption-crystallization experiment illustrated that the prepared HGS possesses hybrid pH-temperature responsibility for high-efficiency interfacial nucleation and concentration regulation functions, which can be used as a functional micro-platform to control solution crystallization. HGS was introduced into the mixed crystal slurry of uric acid dihydrate crystals (UAD) and simulated body fluids (SBF) to adjust the crystallization process and crystal morphology of sodium urate monohydrate crystals (MSUM). Studies showed that the addition of HGS can strengthen the crystal conversion process, and the crystallization duration was shortened from 72h to 20h. At the same time, HGS can also promote crystal growth and crystal agglomeration. Diverse crystal morphologies can be obtained in an efficient manner, which entirely distinguished from the one prepared via no-HGS. This work explored a new path for further revealing and developing crystal morphology control with hydrogel interfacial materials.

Ansamitocin is a maytansinoid antibiotic from microorganisms, and has extraordinary anti-cancer activity. Ansamitocin P-3 (AP-3) content is maximum during ansamitocins fermentation and it shows strong effects on treatment of breast cancer. However, the low yield of AP-3 limits its commercial application. This review summarizes the biosynthesis and metabolic regulation mechanism of AP-3. Also, the isolation and screening of strains, the control and optimization of fermentation process and separation and purification technology are analyzed and discussed. Meanwhile, we look forward to the methods utilized in the future to screening high-yield strains as well as developing high-efficiency and low-cost separation and purification processes, such as new mutagenesis technology, synthetic biology technology and cofactor engineering, in order to improve the fermentation level and lay a solid foundation of industrialized ansamitocin.

Dual drug-loaded core-shell microspheres were successfully prepared by single and coaxial electrostatic spraying methods under mild conditions with poly(lactic acid-co-glycolic acid) (PLGA) as the core matrix and poly(vinylpyrrolidone) (PVP) as the shell matrix. Vancomycin hydrochloride (VA) as an antibacterial model drug was loaded into the PVP shell and osteogenic dexamethasone (DA) as an osteogenic model drug was loaded into the PLGA core. The results showed that when PVP concentration is 80g/L, both single and coaxial electrostatic spraying methods could obtain core-shell microspheres with good spherical shape and distinct core-shell structure. The results of X-ray diffraction (XRD) and differential scanning calorimeter (DSC) showed that DA is amorphous when it is encapsulated into the microspheres. Based on the water-solubility of PVP and the slow degradation of PLGA, these core-shell microspheres can achieve the rapid-release of VA and the sustained-release of DA. The programmed sequential release behavior of these dual drug-loaded core-shell microspheres endows them with potential applications in the drug controlled-release and tissue engineering.

As a derivative of furan, 2,5-furandicarboxylic acid (2,5-FDCA) is a biomass-based platform compound with good stability and high additional value, which has been widely used in many fields such as polyester, polyamide, polyurethane, thermosetting materials, plasticizers, etc. How to prepare 2,5-FDCA greenly and efficiently has been paid wide attention in recent years. In this paper, starting from various biomass-derived raw materials, the methods and characteristics of synthesizing 2,5-FDCA with 5-hydroxymethylfurfural (HMF), furoic acid, and adipic acid were reviewed. The yield of other routes such as hexosedioic acid is low, which is not conducive to industrial development. The HMF route has the advantages of high yield and few by-products. However, due to the conflict between the source of raw materials and the food industry and the high production cost, the use of inedible biomass-derived raw material furoic acid to synthesize the target product at low cost will become an important research direction for future sustainable development. On this basis, after comparing the advantages and disadvantages of each route of furoic acid, it was found that the CO{}_{\mathrm{3}}^{\mathrm{2}-} promoted synthesis method of furoic acid carboxylation does not require a reaction solvent, and the catalyst component is simple and renewable, which are conducive to low-cost synthesis products. And due to the simple process flow and high product selectivity and yield, the furoic acid carboxylation method will become a highly potential route for green large-scale production of 2,5-FDCA.

Riboflavin is widely used as medicine, pigment, nutritional additives, and feed additives. At present, riboflavin in production and sale is mostly needle-like crystals with low bulk density, poor dispersion and fluidity, which affects the processing performance, e.g. tableting. In this paper, five methods of riboflavin crystal purification, such as acid dissolving method and alkali dissolving method, were screened, and the comprehensive benefit of the yield and purity of acid dissolving method was found to be the best; on this basis, ultrasonic assisted crystallization was used to optimize the power, time and temperature, and the results were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD) and other characterization methods. The results show that the optimum parameters for ultrasonic crystallization are: the ultrasonic power is 400W, the ultrasonic time is 40 minutes, and the ultrasonic temperature is 50℃, the yield of riboflavin can reach 95%, and the purity is more than 96%. The crystal habit and crystallinity of riboflavin are improved, which is convenient for its processing and application.

Indole widely exists in industrial wastewater such as coking, dyes, chemicals, pharmaceuticals and pesticides. Due to bicyclic fused structure of indole, it is difficult to improve the degradation efficiency of indole by traditional biohydrolysis. This paper is dedicated to offering a comprehensive picture of the indole degradation by advanced oxidation processes (AOPs). Accordingly, sources, toxicity, hazards and defects of traditional biodegradation technology are introduced. Moreover, the formation reaction of ·OH in the AOPs and the mechanism of indole degradation are analyzed. Traditional AOPs can efficiently degrade indole, but they are difficult to apply in large-scale water treatment projects due to their high cost, complicated operation, and the easy introduction of new pollutants. Therefore, it is considered that the efficient coupling of AOPs pre-oxidation and biological treatment technology is a cost-effective way to degrade indole. Finally, the research on indole degradation by advanced oxidation technology of sulfate radicals (SR-AOPs) coupled with anaerobic biotechnology is introduced, along with its advantages. These studies have a reference value for enriching the theory of AOPs coupled biological treatment technology, efficient degradation and carbon resource utilization of nitrogen heterocyclic compounds (NHCs).

Metal organic frameworks (MOFs) synthesized by self-assembly of inorganic metal ions and organic ligands with high porosity and adjustable window size endow the MOFs mixed matrix membranes with both high flux and high rejection, which are expected to break the trade-off effect between permeability and selectivity of traditional membranes. This paper reviews the typical structures of MOFs, the preparation methods and the key influence factors of the performance of the MOFs mixed matrix membranes, and the principle of MOFs nanoparticles for improving the water transport and solute separation performance. Besides, the latest research progresses of the MOFs mixed matrix membranes in the fields of microfiltration/ultrafiltration, nanofiltration/reverse osmosis, and forward osmosis for water treatment are introduced. Finally, several critical issues in the future development of the MOFs mixed matrix membranes for water treatment are summarized, mainly including the controllable preparation of the membranes with high-performance and low-cost, the deep exploration of the quantitative structure-function relationship between membrane structure and performance, and the expanding of their application scopes, which have guiding significance for speeding up the industrialization process of the MOFs mixed matrix membranes.

The amount of wastewater from coal chemical industry is large and the water quality is complex with the highest COD of 30000mg/L. This typical industrial wastewater is difficult to be treated. The main pollutant constituents in coal chemical wastewater are oily substances, phenolic substances, and ammonia nitrogen and their highest concentrations can reach 10000mg/L, 9000mg/L, and 4000mg/L, respectively. It will cause a serious waste of resources if they are not recycled. Therefore, the effective recovery of oil, phenols, and ammonia nitrogen is a significantly ignored issue for realizing the harmless treatment of coal chemical wastewater. This review summarizes the current status of the recovery technologies for oily substances, phenolic substances, and ammonia nitrogen in coal chemical wastewater from three aspects, including oily substance recovery technologies, phenolic substance recovery technologies, and ammonia nitrogen recovery technologies. Furthermore, various technologies in terms of their advantages and disadvantages are analyzed for the understanding on the research status and development trend of oily substances, phenolic substances, and ammonia nitrogen recovery technologies in coal chemical wastewater. Finally, based on the development concepts of energy saving, high efficiency, and sustainable health, the recovery prospects of oily substances, phenolic substances, and ammonia nitrogen are discussed.

Malodor is of great concern during the collection, transportation and treatment of domestic waste. Therefore, the control of malodor has become one of the huge challenges that domestic waste management is facing. Thereby, the monitoring and analysis of malodor is the prerequisite for effective control of malodor for domestic waste management. In this article, methods for odorous gas sampling and sample analysis in various processing stages of domestic waste such as collection, transportation, treatment and disposal were summarized, from the perspective of sample collection, storage, pretreatment and instrument detection methods. Besides, problems relating to odorous compounds monitoring and analysis process were sorted out. Relevant suggestions were put forward.

In order to reduce NO_x emission concentration of the boiler, a diffused low-nitrogen burner suitable for gas-fired boiler was designed by using the principles of flue gas internal and external circulation, swirl combustion and flame stabilization technology. The industrial experiment was carried out on the 2.8MW gas-fired boiler, and the numerical calculation was carried out at the same time. The industrial experiment and numerical calculation showed that fuel consumption, excess air coefficient and flue gas circulation rate all affect NO_x emission concentration, but the influence degrees of the three are different. With the increase of fuel consumption, NO_x emission concentration increases. With the increase of excess air coefficient, NO_x emission concentration first increases and then decreases. With the increase of flue gas external circulation rate, NO_x emission concentration decreases. For the burner here, when the flue gas external circulation rate is controlled within the range of 28% to 40%, the excess air coefficient only needs to meet the requirement of fuel complete combustion,the NO_x emission concentration will be lower than 30mg/m³. When the flue gas external circulation rate is more than 40%, it is prone to combustion instability, and when it is lower than 28%, the NO_x emission concentration will be higher than 30mg/m³, which cannot meet the emission requirements.

As an important secondary resource, neutralizing iron slag in zinc hydrometallurgy contains a lot of valuable metals such as iron, ferrum and zinc, which has a high value of comprehensive recovery and utilization. Before the recovery of valuable metals, the neutralizing iron slag needs to be dehydrated and pretreated. Based on the problems of long drying time, low drying efficiency and secondary pollution in the rotary kiln drying method, the experimental research on the neutralizing iron slag in zinc hydrometallurgy by microwave drying was carried out. The experimental study on the influence of microwave power and material quantity on the temperature rise behavior of neutralizing iron slag showed that it is feasible to dry the neutralizing iron slag in zinc hydrometallurgy by microwave drying. The effects of microwave power, material quantity and drying time on the dehydration rate of neutralizing iron slag were investigated. The results showed that, to some extent, the dehydration rate of neutralizing iron slag is directly proportional to drying time and microwave power, and inversely proportional to the amount of material. When the microwave power is 1000W, the material quantity is 50g and the microwave drying time is 9min, the dehydration rate of neutralizing iron slag is 98.55%. XRD and FTIR analysis showed that the iron slag was completely removed in microwave drying. SEM analysis showed that microwave drying was more uniform than conventional drying. Compared with the conventional drying process, microwave drying has the advantages of short drying time, high water removal rate, drying uniform, clean and pollution-free.

To investigate the spatial-temporal differentiation of total organic carbon (TOC) and black carbon (BC) in the sediments of urban water source reservoirs, and their impacts on polybrominated diphenyl ethers (PBDEs), a class of typical persistent organic pollutants (POPs), sediments of the Shanmei Reservoir and its inflowing river in Quanzhou, China were analyzed to realize the contents, total inventories, spatial distributions, hydrological period changes of TOC and BC, the relations between BC and TOC and their influences on the spatial and temporal differentiation of PBDEs. Results showed that the TOC and BC contents were 15.08mg/g±2.70mg/g (10.87—19.61mg/g) and 3.55mg/g±1.14mg/g (2.08—6.92mg/g) respectively, and the total inventories were 107445t and 25294t, which were at the lower-middle levels compared with other lakes and reservoirs at home and abroad. Distinct differences were found in the spatial and temporal differentiation between TOC and BC. TOC was significantly affected by the hydrological period changes (P<0.001), while BC was significantly affected by the spatial distributions (P=0.001). There were no significant correlations between TOC and BC (P≥0.226), indicating that their sources were different. TOC was more susceptible to the influx of inflowing river than BC. The BC/TOC ratios (wet 0.24±0.09, dry 0.21±0.06, normal 0.27±0.08) of each hydrological period in Shanmei Reservoir were between 0.11 and 0.5, indicating that BC was generated by the combined sources of both biomass burning and some fossil fuel combustion. BC in the inflowing river was more affected by biomass burning than the reservoir area. The spatiotemporal differentiation of ΣPBDEs, Deca-BDE and Nona-BDE were significantly affected by TOC, and the spatiotemporal differentiation of the major lower brominated BDE produced by Deca-BDE degradation were also affected somehow by TOC to some extent. The primary pollution source of TOC and PBDEs in each hydrological period was the same, both was the inflowing river, and their spatial distributions were roughly the same. TOC was an important controlling factor for the spatial and temporal differentiation of PBDEs. There were no significant correlations between BC and PBDEs in each hydrological period due to their different sources, but BC could adsorb a large amount of PBDEs released by local pollution sources, which still had a considerable impact on their spatiotemporal differentiation.

A great deal of sewage with heavy odor, high COD, strong alkalinity, high salinity and poor biodegradability will be produced during the condensation production of butyl alcohol and 2-ethyl hexanol, in which the COD concentration is up to 80g/L. A new process for treating butyl alcohol and 2-ethyl hexanol condensation sewage was presented in this paper, that is, “acidification-oil trap”pretreatment-heterogeneous ozone-catalyzed oxidation treatment-disc-tube reverse osmosis (DTRO) membrane treatment further treatment. The effects of catalyst type, pH and reaction time on the treatment were investigated. Then the influence of operating pressure on COD and TDS of treated water quality was investigated in the process DTRO membrane process. It showed that the butyl alcohol and 2-ethyl hexanol condensation sewage pretreated with acidification and oil isolation at pH≤3, then the sewage was adjusted to pH 7. After that, it carried out by heterogeneous ozone-catalyzed oxidation for 120min, finally the operating pressure of DTRO membrane treated the oxidized sewage under of 7MPa. According to the test, the COD removal rate of butyl alcohol and 2-ethyl hexanol condensation sewage could reach 99.6%.

As a kind of agricultural by-product, wheat straw can be used as raw material for the preparation of biobased chemicals. Methyl levulinate (ML) is a kind of biobased chemical with wide applications. Using wheat straw pretreated with alkali as raw material and copper sulfate as catalyst, the process of preparing ML was studied. The effects of reaction temperature, reaction time and catalyst dosage on the yield of ML were investigated. Through optimization, the ML yield of 23.0%(mass fraction) was achieved under the reaction conditions of temperature 183℃, reaction time 3.3h and catalyst dosage 0.53g. Meanwhile, copper sulfate had good catalytic activity after repeated use, and the ML yield reached 18.7%(mass fraction) after five times of use. Under the same optimized conditions, the developed process improved the ML yield by 8.6%(mass fraction) compared with the ML yield from unpretreated wheat straw.

Carbon tetrachloride (CTC) is a byproduct of chloromethanes industry and an ozone-depleting substance (ODS). Its conversion to chloroform can achieve both ODS production phaseout and recycled resource utilization. A new method for converting CTC to chloroform was developed by using tetrabutylammonium fluoride (TBAF) as phase transfer catalyst, K₂CO₃ as co-catalyst and trichloroethylene as hydrogen donor. The effect of temperature, composition and usage of the catalysts on the reaction was studied, and the reaction kinetics and the scale-up effect were investigated. The results showed that radical substitution took place between CTC and the acidic H-atom of trichloroethylene under basic conditions, forming tetrachloroethene and chloroform. The reaction rate increased with increasing usage and basicity of the catalysts. The catalytic activity of the catalysts declines slightly in the recycled uses due to the partial fluorination of polychlorinated alkanes by TBAF. The overall reaction rate followed the pseudo-first order model with insignificant scale-up effect. Under optimal conditions (30—60℃,9g CTC, 10mmol trichloroethylene, 1 mmol TBAF, 10 mmol K₂CO₃, 0.5 h), trichloroethene can be converted completely with over 95% chloroform selectivity.

To prepare phosphate adsorbent with low cost, biochar was prepared by means of heating walnut shell with LaCl₃ as modified reagent. Biochar was characterized by SEM-EDS, ICP-OES, FTIR and XRD. Adsorption isotherm model and kinetic model were used to fit the phosphorus absorption characteristics of biochar, and effects of pyrolysis temperature, La modification concentration, additive amount, initial solution pH and co-existing ions on biochar absorbing phosphorus were studied. The results indicated that the adsorption capacity of La modified biochar can be significantly improved because La₂O₃ and LaOCl was loaded on its surface. The fine biochar (BC-La400) with the Langmuir maximum phosphorus adsorption capacity of 12.18mg/g can be obtained at pyrolysis temperature of 400℃ and La modification concentration of 0.1mol/L. Adsorption process was mainly controlled by chemical adsorption and intra particle diffusion. When the initial phosphorus concentration was 50mg/L, the optimal concentration of BC-La400 was 2.7g/L. However, after the concentration exceeded 4.0g/L, the phosphorus removal efficiency was above 98%. The optimal initial pH for phosphorus adsorption by BC-La400 was 3. The coexistence of carbonate ions can significantly weaken the adsorption capacity of BC-La400 to phosphorus.

Blast fragment and thermal radiation are important damage factors which contribute to Domino effect accidents escalation. In an actual accident scenario, a storage tank hit by blast fragment is also often subjected to the high-temperature load of surrounding fire. To study the vulnerability of tank under impact of fragments and high temperature, the limit state equation of the target storage tank under the coupling effect of temperature load and impact load was established, and the Monte-Carlo simulation is used to draw the vulnerability curve of the tank hit by fragments under different temperature, considering the effects of mass, speed and angle of fragments. The results showed that the mass and the impact angle of blast fragments are negatively correlated with the vulnerability of target tank, while the velocity of blast fragments is positively correlated with the vulnerability. When the mass of blast fragments is set as variable, in temperature ranges of 20—400℃ and 400—600℃, the average increased values of the maximum failure probability of the target storage tank for every 100℃ increase in temperature are 3.7% and 6.7%, respectively. When the velocity of blast fragments is regarded as variable, within the temperature range from 20℃ to 600℃, the average increased value of the maximum failure probability of the target storage tank is 3.9% for every 100℃ increase. When the impact angle of blast fragments is considered as variable, within the temperature range from 20℃ to 600℃, the average value of the maximum failure probability of the target storage tank augments from 0.675% to 7.01% for every 100℃ increase. The research is of great significance for evaluating the damage of tanks triggered by blast fragments in high temperature environments and for Domino effect accidents pre-control.