The current situation and development trend of ethylene/propylene industry and the connotation of chemical process intensification were summarized and refined. By deeply analyzing the latest key progress and trends of external field synergistic intensification, core reactor/equipment intensification, system coupling intensification and new material (media) intensification in ethylene/propylene production process, four suggestions on the development of process intensification technology in ethylene/propylene production process including accelerating the pilot and promotion of mature/near-mature process intensification technologies in key production processes, promoting the research and development of disruptive and platform process intensification technologies, emphasizing the overall optimization of the ethylene/propylene production process by coupled process technologies and playing the role of advanced information technology in accelerating the ethylene/propylene production process were proposed. It would provide an important reference for the formulation of the development strategy of olefin industry chain process intensification technology in China's petrochemical industry.

Microfluidic technology characterized by microscale process enhancement has the characteristics of high mass and heat transfer efficiency, rapid reaction rate, small reactor size, high controllability and easy amplification, making it be applied in various aspects. Among them, in the field of fluid mixing, microfluidic channels can enhance the mass transfer between multiphase fluids, realize the rapid mixing of samples, and thus intensify the reaction processes. The common methods used for enhancing mixing can be roughly divided into three categories: changing the type of main channels at the junction of side channels (such as from T-junction to co-axial flow-focusing), changing the internal structure of microchannels (such as from normal channels to channels with internal baffles), and altering the flow type of fluids (such as from laminar flow to Taylor flow). This review analyzes the design and principles of different types of microfluidic channels, describes the mixing enhancement effect of different types of microfluidic channels, and introduces the application of microfluidic channels in the preparation of functional materials such as nanoparticles. Microfluidic process enhancement technology provides a safer, more controllable, more efficient and continuous reactor for traditional chemical technology. In the future, continuous and automatic microfluidic desktop factory systems will be more widely used for process intensification.

In order to reveal the mechanism of surface strengthening coating effectively improving wear resistance and stability of high-speed bearing cavity oil lubricated mechanical seal, in this paper, the end face deformation and friction and wear performance of mechanical seal enhanced by Cr coating were analyzed by combining numerical analysis and experiment. The influence of friction pair of Cr coating with different thickness on the temperature and deformation of the end face was analyzed by thermodynamic coupling numerical simulation. The influence of corresponding friction pairs on friction coefficient and wear quantity was studied using friction and wear testing machine. The temperature rise and sealing effect of the end face were tested with a high-speed sealing prototype, and the mechanism of friction and wear enhancement of the end face was explored. The results showed that under the action of thermo-mechanical coupling, divergence deformation occurs on the end face of high-speed seal. The wear of end face was mainly abrasive wear, while local adhesive wear occurred on the outside of end face. Compared with non-coating sealing end face, Cr coating end face had less deformation and low temperature rise. Stable friction transfer film on Cr coating was easier to form. Appropriately increasing the thickness of Cr reinforcing layer was beneficial to reduce the temperature rise of the end face and improve the seal stability. The optimal coating thickness was about 0.15mm under high speed and light load conditions. The results of this paper can provide reference for material selection and structure optimization of high-speed bearing cavity oil lubricated mechanical seal.

In view of the eccentricity problem of labyrinth seal and honeycomb seal in the operation of turbine machinery in the chemical industry, a high-speed rotating seal test device was established in this paper. Through the test, the radial and angular eccentricity conditions of different seals of high-speed rotating machinery in the chemical industry were truly restored, and the leakage characteristics of different structural seals under different radial and angular eccentricity conditions were studied. The sealing mechanism of labyrinth seal, honeycomb seal and honeycomb-labyrinth seal under eccentricity was revealed, which provided theoretical support for the design and optimization of labyrinth seal and honeycomb seal of chemical turbine machinery. This paper mainly compared the leakage characteristics of labyrinth seal, honeycomb seal and honeycomb-labyrinth combined seal under radial eccentricity and angular eccentricity. The main results showed that the honeycomb-labyrinth structure had the largest leakage under all test conditions, but the sensitivity to eccentricity was the lowest and the influence of eccentricity was the smallest. The honeycomb-smooth axis structure had the smallest leakage under all test conditions, which can effectively hinder the gas flow. The labyrinth-smooth axis structure had the highest sensitivity to eccentricity under all test conditions, and was most affected by eccentricity, which reflected the obvious instability.

According to the structural characteristics of the water wall of a 600MW supercritical unit boiler, various headers and complex parallel pipes in the water wall system were simplified and equivalent to pressure nodes and flow circuits to establish the hydrodynamic calculation model and metal temperature calculation model for the water wall system. Hydrodynamic calculation and metal temperature calculation were solved for the boiler in Boiler Maximum Continuous Rating (BMCR) load, design 30% BMCR load and 30% BMCR during deep peak shaving operation. The flow distribution of the water wall, pressure of each header and the metal temperature of the pipe along the direction of the working fluid flow under the initial constant pressure was increased before and after the 30% BMCR load was obtained. The calculation results showed that the flow distribution of the vertical tube panel changed from negative response to positive response after the initial constant pressure was increased, which was conducive to the safety of vertical tube screens. Under the three loads, the peak metal temperature of the boiler water wall was within the allowable range, and the water wall was safe and reliable. The increase in operating pressure improved the safety of the vertical water wall under lower load operation.

In order to improve the stability of the system operation of the high temperature heat pump steam system with R1233zd(E) as the refrigerant under off-design conditions, a simulation model of the system was established based on Modelica to investigate the effect of the factors, such as with or without internal heat-exchanger (IHX), and heat source temperature, mass flow rate, and refrigerant mass flow rate on the system performance. The results showed that the coefficient of performance (COP) of the system improved by 16.1% after adding the IHX, the performance parameters tended to be more stable along the flow direction of the refrigerant, the farther away from the fluctuating source, and the sensitivity of the state parameters was ranked as: refrigerant flow perturbation>heat source temperature perturbation>heat source mass flow perturbation. In addition, the stability of all performance parameters under disturbances was improved by adjusting the throttle valve opening through a PI controller to improve the system's immunity to disturbances, especially the steam output under the refrigerant mass flow disturbance of the process was changed from unstable to more stable 140°C steam output, and the steam production under the three disturbance factors increased by 20.8%, 3.0% and 1.9%, respectively.

In order to study the effect of working conditions on the new self-priming jet flexible impeller, the mixing power consumption of agitator, stress distribution and vibration characteristics of impeller were analyzed by experiment and one-way fluid structure coupling numerical simulation. The results showed that the power criterion of the flexible Rushton impeller was 121.93% higher than that of the self-priming jet flexible impeller under the same operating conditions, and decreased with the increase of Reynolds number. The maximum stress of self-priming jet flexible impeller was lower than the allowable stress of the material within the scope of this study, located at the connection between the support and the blade. The natural frequency and vibration mode of self-priming jet flexible impeller were compared and analyzed under static modal and prestressed modal. The vibration modes with 1st to 8th order were the bending type and that with 9th to 12th order are the torsional type. Compared with static modal, the maximum deviation of natural frequency and vibration maximum value under the prestressed modal were 0.25% and 27.56%, respectively. The prestressed modal natural frequency increased with the increase of impeller rotational speed and the medium kinematic viscosity, but the increase ratio of same order natural frequency was little. The strength and stability of the self-priming jet flexible impeller under various working conditions can be guaranteed, and the mixing efficiency can be effectively improved. The advantage of self-priming jet flexible impeller was obviously in mixing efficiency. This study provided the basic data for the strength and stability of the impeller under various working conditions.

The efficient and safe exploitation of offshore oil and gas fields is a necessary means to practice the national deep sea strategy and explore the future strategic energy sources. Plugging of multi-phase mixed transportation pipelines operating at low temperature and high pressure in deep water has become an urgent problem for safe production and flow assurance in energy industry, and the rapid formation of natural gas hydrate is the main trigger for this problem. To clarify the mechanism of hydrate slurry plugging in oil-water system, to develop green and environment-friendly low-dosage hydrate inhibitor, and to master the multi-phase flow characteristics of slurry will provide theoretical basis and technical guidance for multi-phase mixed transportation flow assurance in deep-water oil fields. To this end, this paper summarizes and outlines the research progress of flow assurance of hydrate slurry in oil-water system from the aspects of hydrate plugging mechanism, chemical methods to prevent and control hydrate plugging, and flow characteristics of hydrate slurry; it should further quantify the effect of these factors on flow resistance and pipe blockage, and establish a theoretical system for assessing the risk of hydrate blockage in industrial pipelines. With the aid of microscale experiments and molecular dynamics simulations, it will clarify the inhibition mechanism of different types of KHIs and the anti-agglomeration mechanism of AAs. It is also proposed that combining experimental exploration, theoretical analysis and numerical simulation, the coupling relationship between particle microscopic behavior and macroscopic physical parameters of flow field is analyzed to quantitatively characterize slurry rheology and flow resistance.

Separator is an important part of lithium ion battery, which significantly impact the safety and performance of the whole battery. At present, the pace of localization in China is accelerating, and there are obvious achievements and progress in the area of lithium-ion battery separators. The market share and production capacity in China are in the forefront of the world, but the high-end diaphragm market is still monopolized by foreign companies. Therefore, in order to further increase the localization rate of the high-end market, it is still necessary to strengthen the research on lithium-ion battery separators. This paper mainly expounds the main functions, types, performance differences, advantages and disadvantages of various battery separators, and the corresponding development status and progress. At the same time, the preparation process of lithium battery separators is described in detail. The types of diaphragms and different modification methods are summarized, including the differences in diaphragm performance caused by different modification methods, and the performances of several commercial separators and cellulose paper-based separators are compared. Finally, the future developments of lithium battery separator are summarized and prospected.

At present, perovskite materials are widely used in the treatment of automobile tail gas, sewage treatment and fuel cell. However, there are limited reports on the application of those materials in coking inhibition during the thermal cracking of hydrocarbons. In this paper, La_1-x Sr _x MnO₃ perovskite-type coatings were prepared by the slurry method on the HP40 stainless steel substrate with aluminum dihydrogen phosphate as the binder. The phase composition and microstructure of the coatings and the coke layers were characterized by XRD, SEM, EDS and Raman spectroscopy. The chemical states of the elements in the coatings were analyzed by XPS. The coking inhibition performance of the coatings were evaluated through the pyrolysis of naphtha. The results showed that La_1-x Sr _x MnO₃ perovskite coatings were uniformly formed on the metal surface with a thickness of about 30μm and well adhered to the substrate. The coating particles were tightly bonded although a small amount of micropores were presented in the coatings. La_1-x Sr _x MnO₃ perovskite oxides presented a featured cubic crystal structure. Furthermore, the incorporation of Sr into the lattice of LaMnO₃ did not change the perovskite phase. Compared with undoped LaMnO₃ perovskite coating, the doping of Sr into the coatings resulted in the higher ratios of O_ads/O_latt and the formation of more oxygen vacancies. The anti-coking rate was increased with the doping content of Sr in the coating. When the cracking time were 3h and 5h, the coking inhibition rates were 84.88% and 82.31%, respectively. La_1-x Sr _x MnO₃ perovskite coatings not only suppressed the catalytic coking by blocking the activity of the substrate metal but also mitigated the coke deposition by catalyzing the oxidation combustion of the coke deposits. Moreover, the doping of Sr into the coatings generated more oxygen vacancies which increased oxygen mobility and promoted electron transfer, and thus improved the catalytic activity of coke combustion. An increased proportion of disordered coke deposits and a decreased graphitization degree were found in the coke layers of La_1-x Sr _x MnO₃ coatings, which would facilitate the decoking operation.

Microwave drying is an advanced technology to improve the drying efficiency of coal slime and intermittent drying technology has greater improvement potential in energy consumption and overtemperature. In microwave drying process, dielectric properties of coal slime can significantly affect the drying performance. However, there is a lack of research on the mechanism of influence of dielectric properties on microwave drying of coal slime. A multiphase porous media model was developed for intermittent microwave drying. Then the validity of the model was verified by comparing with experimental data in literature. Considering that the dielectric properties were function of temperature and moisture content, the influence of temperature and moisture content-related dielectric properties (VP) on the average temperature, vapor mass fraction, gas phase pressure and liquid water saturation of coal slime was analyzed in this paper by comparing with the conventional method (CP) which treated dielectric properties as constant. The results showed that average temperature of the CP was significantly lower than VP, and temperature rise rate did not change significantly during drying process, while average temperature of VP showed a trend of increasing sharply at first and then maintaining stability. Although the vapor mass fraction and gas pressure distribution trend of CP were the same as VP, CP was significantly lower than VP. VP could simulate the "pumping effect" during intermittent microwave drying, whereas CP could not effectively show the phenomenon. VP was more realistic than CP.

Traditional calcium carbide production takes lumpy quicklime and lumpy coke as raw materials and completes the smelting reaction of calcium carbide under the high temperature of electric heating (above 2000℃) in submerged arc furnace. A newly proposed smelting process with homogenization and preheating takes low-grade pulverized coal and quicklime powder as raw materials, and adds the processes of pelletizing and pyrolysis before smelting, in order to achieve the effect of cost reduction and energy saving. In this paper, the mass and energy balance models of the two processes were constructed, and the material and energy flows were simulated under the same calcium carbide discharge conditions to discuss the energy substitution effect of the new process. Based on exergy flow and unit price of exergy, a thermoeconomic cost analysis model was established to compare the thermal economy of the two processes. The results showed that, for 1 ton of calcium carbide produced by the new process, 810.0kg of low-grade pulverized coal needed to be consumed, and 206.2kg of by-product energy was generated in the pyrolysis process. Its net consumption of carbonaceous energy was basically equivalent to that of the traditional process (583.5 kg coke). The characteristic of "replacing coke with coal" of the new process was reflected. The physical enthalpy of hot pellets was directly brought into the furnace through hot delivery and hot charging, which can save about 11.2% heating power consumption, and had the effect of "replacing electricity with heat". The thermoeconomic cost per ton of calcium carbide for the traditional process and the new process was 2208CNY and 1919CNY, respectively. The cost reduction of the new process mainly came from the reduction of power consumption, the increase of net by-product gas generation and the substitution of low-grade raw materials, whose contribution were 8.7%, 6.0% and 3.5%, respectively. The current equipment cost of the new process was relatively high, and its thermal economy advantage will be gradually displayed in the follow-up process promotion.

The production of ammonia by electrocatalytic nitrogen reduction reaction (NRR) at room temperature has attracted extensive attention due to its low energy consumption. So far, the research focus is to design highly efficient electrocatalysts. Metal organic framework (MOF) and their derivatives have wide applications in gas capture, separation, and catalysis due to their unique porous structure and controllable compositions. This review first discusses the mechanism of NRR, and then focuses on the research progress of NRR electrocatalysts of MOF and the derived materials. Finally, we summarize and prospect the design strategy, existing problems of the MOF based NRR electrocatalysts and the challenges in NRR catalysis. In addition, this review points out that: ① The reasonable design of self-supporting MOF electrocatalyst can substantially improve the NRR performance; ② The effective combination of machine learning, DFT calculation and in situ testing technology has important guiding significance for NRR mechanism study, efficient design and screening of catalysts, etc., which will become the future research trends of NRR catalysis.

The development of high-performance catalysts is essential to improve the residue hydrogenation quality. In this review, the effects of alumina support and catalyst preparation method on the structure and stability of the active phase were introduced. Firstly, it discussed the influence of alumina surface properties (type and concentration of hydroxyl groups, surface-dependent orientation), crystal phase (γ-Al₂O₃, η-Al₂O₃, δ-Al₂O₃, θ-Al₂O₃, α-Al₂O₃), and pore structure (pore size distribution and specific surface area) on the metal-support interaction. Then, the modifications of hydroxyl, acid, and pore structure on alumina surface by hydrothermal treatment were analyzed. Subsequently, the effects of additives and sulphuration conditions on the structure of the active phase were outlined in catalyst preparation. Then the structure-activity relationship between active phase and catalytic performance was summarized. Finally, it pointed out the necessity to balance the large pore size and high mechanical strength, and to regulate the macroscopic distribution of active components on the support according to the specific demand. Moreover, the pore structure design of industrial catalysts and in situ characterization techniques should be considered in future researches.

Hydrofluoroolefins (HFOs) have great potential in many applications due to their superior properties of zero ozone depletion potential (ODP) and low global warming potential (GWP). 1,1,2-Trifluoroethene (TrFE), a novel HFO compound, is considered as a promising candidate of a heat pump working fluid in the air-conditioning system for the new energy vehicles or being used to synthesize the fluoropolymers which are further used as piezoelectric and electrocaloric cooling materials and to synthesize the high value-added alkenyl halides for microchips. In this review, we categorized the existing approaches for TrFE synthesis. The technical challenges of each method were elaborated and the potential solutions were discussed. For the most commonly used methods that use 1,1,1,2-tetrafluoroethane (HFC-134a) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) as starting materials, the low selectivity to 1,1,2-trifluoroethene and the deactivation of the catalysts are the most critical challenges, which also limit the scaling-up and the commercialization of the technologies.

Natural gas is a promising clean fuel. The efficient use of methane, the major component of natural gas, is of great practical importance. Among many methane conversion routes, catalytic partial oxidation of methane (CPOM) has the advantages of low energy consumption, suitable syngas fraction and rapid reaction. This paper briefly introduced the CPOM reaction mechanisms (i.e. direct oxidation mechanism and combustion-reforming mechanism), reviewed the current research on four types of CPOM catalysts (i.e. transition metal, noble metal, bimetal and perovskite catalysts), analysed the effects of reaction temperature, carbon to oxygen molar ratio of reactant gas and reaction space velocity on CPOM reaction characteristics, and explained the two main causes of catalyst deactivation (i.e. carbon deposition and sintering) together with their countermeasures. According to the results of the research, the catalytic performance (including methane conversion, syngas selectivity, syngas yield, reaction stability) could be improved by selecting suitable catalyst components, adopting an optimized preparation method and precisely controlling the distribution of active components and microstructure of the catalyst. These method could ensure that more active sites are consistently exposed to the surface of catalyst. Finally, it was pointed out that the rational microstructure design and controlled synthesis of CPOM catalysts and the in-depth study of the CPOM reaction mechanism will remain the focus of future research.

Synthesis of poly(ether carbonate) polyol from CO₂ and epoxides is an effective way of CO₂ chemical utilization. Efficient catalysts can promote the reactions of CO₂ and epoxides to produce high-performance polymer products. This paper summarized the main progress of the catalysts for ring-opening copolymerization of CO₂ and epoxides in the latest three years. Catalysts of metal carboxylates, double metal cyanides, metal Salen complexes, metalloporphyrin and other novel organic catalysts are classified and reviewed from two aspects of heterogeneous and homogeneous catalysts. Inexpensive heterogeneous catalysts are still preferred for industrial applications, but how to control the distribution of active sites in the catalyst preparation process, thereby controlling the quality of polymer products, is the focus of future research. Metal Salen complexes are the hot research areas at present. The diversity of their organic ligand structures endows a variety of metal combinations. It is expected to develop more efficient and inexpensive catalysts in the near future.

Copper (Cu) based catalysts have unique activity in reactions with C\stackrel{}{̿}O, C—H, O—H and H—H bond activation, and have been widely used in hydrogenation reactions of CO _x, aldehydes, acids, esters and alcohol dehydrogenation reactions. However, due to the low Tamman temperature of Cu particles, they are easy to deactivate because of the irreversible particle aggregation, which limits their applications. Herein, the deactivation mechanism of Cu based catalysts was first introduced from the viewpoint of surface energy and particle migration on catalysts. Then, strategies for stabilizing Cu particles including enhancement of metal-support interaction, spatial fixation and alloying were reviewed. Finally, an outlook was present to highlight the direction for Cu based catalysts. Specifically, the deactivation mechanism for Cu based catalysts should be in-depth investigated, and novel catalyst synthesis technologies and methods should be developed to prepare stable and cheap catalysts for reactions with hydrogen.

Linear alcohols with six carbon atoms or more are used extensively in industry. Syngas to higher alcohols is a short route suitable for a wide variety of carbon resources. Cobalt-based catalysts have the Co⁰ active phase to dissociate CO and promote the carbon-chain growth, and Cu and Co₂C active phase are introduced to promote the CO no-dissociative activation and enhance the selectivity towards alcohols. This article summarized the recent progress on Co-catalyzed syngas to higher alcohols, and found the highly dispersed active phases under reaction conditions was the key of high C₆₊OH selectivity. Dispersion of active phase could be improved by pretreatment on the catalyst surface, or via the structure of hydrotalcite or perovskite. Supports and promoters would influence the surface metal segregation and the formation of CoC _x, thus affected the catalytic performance. To improve the selectivity towards higher alcohols and prolong catalyst life, further studies were needed on accurate characterization of catalyst surface state, controllable synthesis technology, dynamic evolution of the catalyst structure and reaction network under the reaction atmosphere.

Hydrothermally stable mesoporous aluminosilicates (MAs) could be obtained via self-assembly of clusters of primary and secondary building units of microporous zeolites. However, high consumption of water and organic template hinder its industrial application. To solve this problem, hydrothermally stable MAs was proposed via the introduction of microporous precursor into the wall of mesophase. Based on the development process of microporous zeolite precursor assembly method, various strategies to decrease the consumption of organic template and water were summarized, including seed-assisted method, mother liquid recycling strategy, introduction of hydrophilic materials, and composite templates method. Based on the analysis of their advantages and disadvantages, future development directions are pointed out. Specifically, the MAs with fully crystallized walls of mesophase without organic template will be the research focus.

Bleached lac is often used in pharmaceutical and food industry, but the binding chlorine added to its double bond structure in the preparation process has a negative impact on its application and performance. The removal of binding chlorine from bleached lac is a hot spot in the research of high value utilization of lac. In this paper, the supported Pd-Fe bimetallic catalyst was prepared by ultrasonic intensification and liquid reduction method using modified multi-walled carbon nanotubes as the support. The catalytic hydrogenation dechlorination of bleach lac over the supported Pd-Fe bimetallic catalyst was studied, and the prepared catalyst was characterized by XRD, XPS, SEM and HRTEM. The results showed that the particle size and lattice parameters of the prepared catalyst were 6.32nm and 2.27Å, respectively. The hydrogenation dechlorination process belonged to substitution reaction and followed the first-order reaction kinetics. The reaction rate constanted at 55℃, 65℃ and 75℃ are 0.0267min^-1, 0.0349min^-1 and 0.0435min^-1, respectively, giving an activation energy of 23.20kJ/mol. Under the optimum reaction conditions, the dechlorination efficiency reaches 93.68% and the chlorine in bleached lac decreased from 2.42% to 0.14% .

Pitch is a complex mixture of a series of hydrocarbons rich in thick rings aromatic hydrocarbons and their non-metallic derivatives with high carbon content. The development of pitch as a carbon material precursor for the preparation of supercapacitor carbon electrode material not only expands the application market of pitch and enhances its added value, but also responds to the national demand for new energy utilization. In this paper, the energy storage mechanism of supercapacitors was firstly described, and the structural factors and laws affecting the electrochemical properties of carbon materials for supercapacitors were discussed. The composition, structural model, sources and applications of pitch were outlined. Then, the research progress of pitch-based porous carbon for supercapacitor electrode materials was reviewed, and the characteristics and progress of pitch-based porous carbon preparation by activation method, template method and molten salt method were analyzed. A summary of the research on the modification of pitch-based porous carbon materials was highlighted. Finally, the advantages and disadvantages of pitch-based porous carbon materials as electrode materials for supercapacitors were pointed out. It is suggested that the asphalt raw materials should be pretreated and carbonized to remove metal heteroatoms from the obtained carbon materials to obtain capacitor carbon with stable and long cycle life. The research on the carbonization law of four components in asphalt should be strengthened, so as to improve the carbonization rate of pitch-based supercapacitive carbon materials. The KOH activation method should be combined with other activation methods in order to reduce the loss of equipment and the impact on the environment on the basis of obtaining high-performance activated carbon.

Biomass-based carbon materials have the advantages of wide source, abundant surface functional groups and diverse microstructures. However, it has the problem of unreasonable pore size distribution, limiting their applications in electrochemical energy storage. In this paper, the influence mechanism of microporous, mesoporous and macroporous structures on electrochemical performance was briefly described, and the pore size regulation methods were elaborated including alkali activation method, foaming activation method, CO₂/steam activation method and freezing treatment method for microporous, acid activation method, template method, molten salt carbonization method, catalytic activation method and cellulase hydrolysis method for mesoporous, and SiO₂-colloidal template method and soft template method for macroporous. Moreover, the influence factors, advantages and disadvantages of the above regulation methods were analyzed, and the application effects of various methods in electrode materials were summarized. The analysis showed that the foaming activation method was efficient and environmentally friendly for microporous regulation, and the acid activation method and molten salt carbonization method improved the mesoporosity significantly. In addition, according to the different sources (components) of biomass materials, the regulation methods were classified. It was found that the alkali activation method and the self-templating method were suitable for microporous and mesoporous regulation of animal-based carbon materials, while the cellulose enzymatic method provided a new green idea for mesoporous regulation of plant-based carbon materials. Finally, some suggestions were put forward on the application of pore size regulation and green preparation of biomass-based carbon materials in electrochemical energy storage.

Polyamide composite membrane fabricated by interfacial polymerization has been widely used in wastewater treatment, seawater desalination and other fields. However, the structure of polyamide composite membrane plays a key role in its application. Most of the previous studies focused on the selective layer, while there are relatively few studies concentrated on the microporous substrate of the composite membrane. The results show that the physicochemical characteristics of microporous substrate exhibit a great influence on the formation of polyamide selective layer and the corresponding properties of the resultant composite membrane. Therefore, this review first introduced the preparation technologies of the substrate, then focused on the different modification methods of the microporous substrate, including the traditional substrate improvement method and the material and structure of the new substrate. Furthermore, the effects of substrate structure on the structure and performance of the pressure-driven membrane (nanofiltration, reverse osmosis) and osmotic pressure-driven membrane (forward osmosis) were discussed. The analyses showed that the microporous substrate with high porosity and good hydrophilicity can effectively regulate the storage and diffusion of the aqueous monomers in the process of interfacial polymerization, which would be beneficial to obtain the polyamide composite membranes with high water permeance and excellent selectivity. Therefore, in the future, it is still necessary to develop more potential microporous substrate materials and construct ideal structures from several aspects such as polymer materials and nano-modification, so as to promote the application and development of the polyamide composite membranes.

With the rapid development of new energy and other industries, the demand for lithium has increased dramatically. Nanofiltration membranes are receiving more and more attention as a method of lithium extraction from salt lakes with the advantages of low energy consumption, low cost and green environment protection. This method can reduce the magnesium-lithium ratio in the brine and reduce the difficulty of subsequent lithium extraction, which has great potential in the salt lake lithium extraction industry. However, due to the late development, the theoretical system was not yet perfect and the process of promoting industrial applications was slow. This paper analyzed the modification methods used to enhance the performance of nanofiltration membranes for magnesium-lithium separation in recent years by starting from the separation mechanism, including five methods of surface grafting modification, two-phase solution additives, new monomer design, base membrane modification and optimization of interfacial polymerization (IP) process. The effects of the various modification methods on the structure and properties of nanofiltration membranes were also described. The analysis showed that the surface modification methods can change the membrane surface charge but cannot precisely regulate the membrane pore size. The additives can reduce the water transport resistance but the membrane tolerance needed to be investigated. The monomer design and base membrane modification can effectively improve selectivity and permeability, and the process optimization was more complex and industrial scale-up was difficult. Overall, the development of nanofiltration membranes in the salt lake lithium extraction industry was very promising. It can achieve green and efficient lithium extraction with other lithium extraction processes.

MXene is a graphene structured layered 2D nanomaterial with high electrical conductivity and large specific surface area, which is commonly used in energy storage. MXene is rich in end-group functional groups, which efficiently facilitated the formation of cross-linked structures with biomass based nanomaterials and then widen the layer spacing of MXene, thus improving the flexibility of devices and providing more ion transport channels. Therefore, the use of MXene in biomass energy storage nanomaterials is becoming a hot topic of research. This paper reviews the recent applications of MXene combining biomass based nanomaterials in the fields of energy storage. Firstly, the various MXene preparation methods and their advantages/disadvantages are introduced. Secondly, the optimized modifications of MXene energy storage devices with CNF, BC, CNC and other materials are presented, respectively. Then, the physical/chemical characteristics and the performance advantages of the three cutting-edge energy storage devices of supercapacitors, nanogenerators and secondary batteries derived from MXene-biomass based nanomaterials are also summarized, followed by emphatically focusing on the functions of biomassbased nanomaterials in MXene-biomass based nanocomposites. Finally, the challenges faced by MXene composited with biomass based nanomaterials in the energy storage areas and their future applications are analyzed and prospected.

Propylene, as one of the basic raw materials of the three major synthetic materials, has a vital position in the national economy, but the energy consumption required for separation and purification in its production process is extremely high. Mixed matrix membrane is prepared by introducing functional nanofillers into polymer matrix and can show excellent separation ability for propylene and propane. It is believed that such membranes can substantially reduce the energy consumption of propylene purification, and has become a hotspot in the field of gas separation. In this study, the effects of polymer structure on the separation performance of propylene/propane membrane are reviewed, and the important factors affecting the separation performance of propylene/propane in mixed matrix membranes is summarized. Then, the progress in propylene/propane separation mixed matrix membranes (MMMs) is reviewed based on the point view of polymer matrix and MOFs filler. The optimization method of MMMs is discussed in detail from three aspects: improving interface compatibility, regulating membrane packing structure and regulating membrane matrix structure. Finally, in view of the problems existing in the process of mixed matrix membranes for propylene/propane separation, the transport mechanism of propylene and propane molecules in mixed matrix membranes is analyzed. The future research on MMMs for propylene/propane separation is also proposed.

Graphene is often used as electrode material for symmetric supercapacitors due to its unique advantages of ultra-high conductivity and large specific surface area. However, the Van Der Waals forces between two-dimensional graphene nanosheets easily lead to sheet stacking. Moreover, the supercapacitor assembled with aqueous solution as the electrolyte may undergo a water splitting reaction during the charging process, resulting in a limited charging voltage, which greatly reduces its energy density. Based on this, in this study, sulfur and nitrogen co-doped three-dimensional graphene aerogel electrode materials were prepared by hydrothermal method. The effects of the microscopic morphology, surface chemical properties and hydrothermal reaction time of graphene materials on the electrochemical properties of the materials were investigated. The results showed that S,N-rGO-2 provided with a well-developed pore structure and high contents of heteroatom elements. The specific capacitance was as high as 358.5F/g at a scan rate of 5mV/s, the charging voltage of the all-solid-state supercapacitor assembled with solid electrolyte can reach 1.8V, the specific capacitance was as high as 118.3F/g at a current density of 1A/g and the energy density reached 14.9Wh/kg. The specific capacitance retention rate and Coulombic efficiency were both close to 100% after 10000 charges/discharges. S,N-rGO-2 exhibited excellent electric double-layer capacitance and can be used as the potential supercapacitor electrode material.

A small amount of thermal reduced graphene oxide (TRGO) was added to commercial solvent-type epoxy resin coatings (EPs) to improve their anticorrosion performances. TRGO was prepared at different temperatures using graphite oxide (GO) as precursor. Structural changes before and after thermal reduction reaction of GO were characterized. The dispersion of GO and TRGO in the diluents of epoxy resin coatings were compared. The TRGO/EPs composite coatings were coated on the surface of Q345 steel. The influence of the preparation temperature and addition amount of TRGO on the anticorrosive performances of the composite coatings were investigated by Tafel polarization curves (Tafel), AC impedance spectra (EIS) and corrosion morphology. The anticorrosion mechanism of composite coating was discussed. The results indicated that high temperature thermal reduction reaction can strip GO and successfully prepare TRGO. Compared with the GO, TRGO showed significantly enhanced dispersion in diluents of solvent-based epoxy resin coatings. The oxygen content of TRGO decreased with increasing thermal reduction temperature, but the TRGO (TRGO-800) prepared at 800℃ had the maximum specific surface area. The TRGO/EPs composite coatings prepared at different thermal reduction temperatures all had better anticorrosion performances than the pure EPs coatings. Among them, the TRGO-800/EPs composite coating had the best anticorrosion effect, and even better than the commercial graphene/EPs composite coating. When the addition amount of TRGO-800 was 0.1%, the corrosion current density was 3.29×10^-8A/cm², which was 96.84% lower than the pure EPs coating, and the polarization resistance value of the composite coatings was 1.38×10⁶Ω, which was 28-fold greater than the pure EPs coating. The enhanced anticorrosive performance of TRGO/EPs composite coatings can be attributed to the good dispersion and physical barrier performance of the TRGO.

Four chitosan quaternary ammonium salts with different alkyl chain lengths were successfully synthesized, including N,N,N-trimethylbenzyl chitosan chloride (TMBC), N,N-dimethyl-N-butyl benzyl chitosan chloride (DMBBC), N,N-dimethyl-N-octyl benzyl chitosan chloride (DMOBC) and N,N-dimethyl-N-dodecyl benzyl chitosan chloride (DMDBC), and characterized by nuclear magnetic resonance (¹H NMR) spectra and thermogravimetric analysis (TGA). Their antibacterial activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated in vitro using the antibacterial assay, minimal inhibitory concentration and minimum bactericidal concentration assay, while antibiofilm activity was quantified by crystal violet staining assay. The antibacterial activity revealed that the alkyl chain length could affect the antibacterial effect of chitosan quaternary ammonium salt. Especially, DMDBC exhibited the best antibacterial property. The MIC and MBC of DMDBC for E. coli were 0.156mg/mL and 0.625mg/mL, respectively, and for S. aureus were 0.039mg/mL and 0.156mg/mL, respectively. At 0.5mg/mL, the antibacterial rate of DMDBC against E. coli and S. aureus could reach 100%. At 1/2 MIC, the inhibition rates of BF formation of E. coli and S. aureus by DMDBC were 76.43% and 76.96%, respectively, and at 2.5mg/mL, the mature biofilm clearance rates of E. coli and S. aureus were 67.60% and 92.93%, respectively.

Liposomes are artificially prepared hollow microspheres, which are assembled from cholesterol, phospholipids and their derivatives. Depending on the diversified phospholipid components, particle size and hollow spherical structure, and a series of electrical, mechanical, material and surface interface characteristics, liposomes have excellent biocompatibility and metabolic properties, targeting and microenvironment response ability. Liposomes have been widely studied in the fields of drug delivery, disease diagnosis, high-end daily chemicals and functional food development. Nano biomedical delivery system is the most successful application of liposomes. Research results and mature products continue to emerge. Based on this, starting from the structural characteristics such as liposome molecular composition, spatial characteristics, electrical characteristics and surface interface mechanics, this paper defines the core points of liposome functional design, innovating preparation technology to improve drug loading and entrapment efficiency, strengthening the enrichment of target sites through surface modification, combining exogenous physical stimulation with structural design to achieve programmed drug release and enhancing membrane penetrating ability to complete the effective entry of liposomes into cells. Combined with the latest research, this paper summarizes the clinical application of liposomes carrying drugs, nucleic acids, vaccines and other substances.

With the aggravation of environmental pollution and the widespread use of antibiotics, various diseases threatening human health have gradually broken out, and the problem of antibiotic resistance of pathogenic bacteria has become increasingly serious. This has prompted many researches to explore new antibacterial agents that are environmentally friendly, have strong antibacterial activity, and do not easily produce drug resistance. Nanotechnology has been proved to be an effective means to fight against pathogens. Zinc oxide nanoparticles have excellent antibacterial properties and are expected to be widely used as new metal ion antibacterial materials. Compared with traditional physical and chemical methods, the biological method of zinc oxide nanoparticles has the advantages of simple operation, high safety, and less environmental pollution. It has become a new trend in the development of nano synthesis technology. In this paper, the biosynthesis methods and synthesis mechanism of zinc oxide nanoparticles using plant, algae and microorganism extracts are first summarised. Then, the antibacterial mechanism and antibacterial applications of zinc oxide nanoparticles in the pharmaceutical industry, textile industry, food industry, agriculture and other related fields are discussed. Finally, the related research and application prospects of innovative multi-metal composite nanoparticles containing zinc oxide are further discussed, providing new ideas for the development of zinc oxide nanotechnology.

Crystallization is an important tool for the cultivation of protein single crystals as well as protein separation and purification. Conventional static protein crystallization has problems such as long operation cycle and uneven crystal size distribution. Droplet microfluidics is a potential method to increase protein crystallization rate and improve crystal size distribution because of its low reagent consumption and high efficiency of mass and heat transfer under low Reynolds number conditions. This study investigated lysozyme crystallization using a droplet microfluidic system under static droplet and low shear rate (flowing droplet) conditions, respectively. The experimental results showed that the microfluidic droplet internal circulation could effectively improve the nucleation rate and crystal number. Furthermore, nucleation rate, average crystal number and crystal size were monotonically dependent on the oscillation flow rate. In addition, the activity experiments showed that the forced circulation of microdroplets did not have a significant effect on the lysozyme activity.

Silicon-containing arylacetylenic polymers have potential applications as one kind of new thermosetting resin. They can be obtained using arylacetylenic monomer or arylacetylenic prepolymer as materials by thermal polymerization. A series of silicon-containing arylacetylenic monomers with different side alkyl groups on the silicon atom, including n-octyl (OTPES), decyl (DTPES) and hexadecyl (HTPES) were synthesized by Grignard reaction with phenylacetylene and different substituted trichlorosilane as raw materials. The chemical structure of monomers was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR), and the effect of alkyl groups on the curing behavior and rheology was studied. The corresponding polymers were prepared by thermal polymerization and the influence of alkyl groups on the thermal stability and dielectric properties was also discussed. The results showed that the gel time increased from 519s to 1222s and the reaction activation energy also elevated from 143.90kJ/mol to 173.05kJ/mol with the increase of the carbon chain length of the substituent. Thermogravimetric analysis indicated that the thermal stability of polymers was affected by the quantity and size of the substituent and the peak Ⅰ decomposition temperature was increased from 464.4℃ to 499.3℃ by peak fitting with the increase of carbon chain length. In the frequency range of 2~18GHz, the real part was between 2.0~2.9 and the imaginary part of dielectric constant was less than 0.3, and the tangent value of dielectric loss was at 0~0.15 of three polymers, showing an excellent wave transmission performance compared with traditional engineering plastics.

Cross-linked α‍-methylstyrene maleic anhydride copolymer microspheres (PAMSM) were prepared by self-stable precipitation polymerization with α‍-methylstyrene and maleic anhydride as copolymer monomers and divinylbenzene as crosslinking agent. Firstly, mono-6-p-toluenesulfonyl-β- cyclodextrin (mono-6-OTs-β-CD) was obtained by the monosulfonylation of β-cyclodextrin (β-CD) with p-toluenesulfonyl chloride, and then 1,2-propylenediamine-‍β‍-cyclodextrin (PDM-‍β‍-CD) was achieved by the ammoniating of mono-6-OTs-β-CD with excess 1,2-propylenediamine. The microspheres of β-CD-PDM-PAMSM were prepared though immobilizing PDM-β-CD to the PAMSM by ringing-open amidation reaction of PDM-β-CD with the primary amines and PAMSM with the anhydride groups. The composition, surface morphology, particle size and distribution of the β-CD-PDM-PAMSM were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and elemental analysis. The results showed that the β-CD-PDM-PAMSM maintained good sphericity and the average particle size was 1.08μm. The immobilization yield of β-CD on PAMSM was high, and the grafting rate of β-CD was 53.1% calculated by the elemental analysis. Then, the adsorption properties for methylene blue solution (MB) of PAMSM, β-CD-PDM-PAMSM, hydrolyzed PAMSM (H-PAMSM) and hydrolyzed β-CD-PDM-PAMSM (H-β-CD-PDM-PAMSM) were investigated. Research suggested that the adsorption capacity of PAMSM for MB was 25.3mg/g, and the adsorption capacity of β-CD-PDM-PAMSM for MB was 615.8% higher than that of PAMSM. The adsorption capacity of H-β-CD-PDM-PAMSM and H-PAMSM for MB was 1043.5% and 860.8% higher than that of PAMSM, respectively.

As an important chemical filler, ultrafine calcium carbonate is widely used in papermaking, ink, rubber, plastics and other industries. With the deepening of carbon emission reduction, the preparation of ultrafine calcium carbonate has become more and more diversified in terms of raw materials and process routes. The use of high-calcium industrial materials, such as steel slag, carbide slag, waste gypsum, etc., as a calcium source coupled with carbon dioxide to prepare ultrafine calcium carbonate has attracted more and more attention. In this paper, the research progress of CO₂ mineralization of high calcium solid waste to prepare ultrafine calcium carbonate is reviewed. The calcium oxide, calcium hydroxide, calcium sulfate and high-calcium industrial solid waste materials are considered and compared. This paper introduces the latest achievements on the preparation of ultrafine calcium carbonate via CO₂ mineralization based on different materials. Meanwhile, the large-scale application and environmental economy of the most representative technology of preparing ultrafine calcium carbonate by industrial solid waste are summarized. Based on the preliminary economic analysis, the reasons for the limitation of current scale-up applications are mainly the control of calcium carbonate crystallization, and the consumption of energy and cost. Thus, in order to better carry out large-scale industrial application, the following suggestions are proposed: firstly, to develop effective control methods for industrial applications aiming at the crystallization process of calcium carbonate based on the microscopic reaction mechanism and the characteristics of solid waste material properties; secondly, to couple the resource recovery of industrial solid waste and the synthesis of refined calcium carbonate technology to promote the development of specific process and devices; and thirdly, to carry out the life cycle environmental and economic assessment based on the development of control methods and equipment.

The thin film composite (TFC) membranes with excellent permeability and selectivity are commonly used for desalination in water treatment. To overcome the membrane performance deterioration because of drying, acid/base hydrolysis, high temperature damage and chlorine oxidation attack during the storage/operating process, numerous works focusing on stability improvement of TFC membranes have been reported. Referring to the most popular nanofiltration/reverse osmosis membranes, this review concluded the damage mechanism of polyamide TFC membranes in the drying process, acid/alkali solution, high temperature and active chlorine solution, and then the strategy of corresponding stability improvement is summarized. By systematically combing the latest research progress of four kinds of "special stable" TFC desalting membranes, i.e., dry resistance, acid/alkali resistance, high temperature resistance and chlorine resistance, it is pointed out that the current research work had problems such as lack of in-depth research on the mechanism of destruction and insufficient attention to the influence between different stabilities. Finally, the research direction in the future is prospected. While further studying the failure mechanism of membrane materials, it should pay more attention to the desalination efficiency and anti-fouling capacity of TFC desalination membranes with special stability, and explore multi-stability TFC desalination membranes, so as to provide reference for future related research work.

CO₂ capture, utilization and storage (CCUS) technology is one of the key technologies to achieve carbon emission reduction. The organic amine absorption technology is the most widely studied and mature CO₂ capture technology, which already has a few industrial application cases. The absorbent is the core of absorption technology. The R&D and innovation of absorbent is the hot topic in this field. Compared with single-phase organic amine absorbents, the biphasic absorbent can significantly reduce the regeneration volume and the regeneration energy consumption, wherein, the homogenous absorbent can be separated into two phases after absorbing CO₂, and only the CO₂-rich phase needs to be regenerated. This paper introduced the typical process, absorption mechanism and research progress of traditional mixed amine biphasic absorbent systems, and analyzed the problems in high viscosity, high rich phase ratio after CO₂ absorption and the resulted increment of regeneration energy consumption. Four types of mixed biphasic absorbents to solve the above problems were systematically combed, including sterically hindered amine mixed biphasic absorbents, physical solvent mixed biphasic absorbents, alcohol amine mixed biphasic absorbents and catalyst-organic amine mixed biphasic absorbents. Moreover, the design and construction principle and performance strengthening mechanism of the aforementioned biphasic absorbents were analyzed. Finally, based on the in-depth analysis of the current research progress, the future research direction of biphasic absorbent was proposed.

Phosphorus (P) is an essential nutrient for biological growth, which exists mainly in the form of phosphate minerals. As a kind of phosphorus-rich solid waste, sludge can be used as a secondary phosphorus resource. In this paper, the rules and effects of phosphorus transformation in sludge under different heat treatment methods (incineration, pyrolysis, hydrothermal carbonization) are summarized. Heat treatment can not only alleviate the crisis of phosphorus resources and promote the recycling of phosphorus resources, but also reduce the environmental problems caused by sludge and generate valuable by-products. On this basis, the influence rules and mechanisms of different additives (coal blending, biomass, and alkaline earth compounds) on phosphorus migration and transformation in sludge are summarized. It is found that the additives could promote the enrichment of phosphorus during heat treatment and change the occurrence form of phosphorus,and increase the biological availability of phosphorus in the ash. This may provide a valuable reference for the research of phosphorus resource recovery and utilization in the process of sludge heat treatment.

Partial denitritation Anammox (PD/A) process has been regarded as a novel biological nitrogen removal process with the most mainstream engineering application prospects in recent years due to its advantages of no aeration, less waste matter yield and less demand for organic carbon sources. Firstly, this paper expounds the principle and characteristics of PD/A process. Then, the paper summarizes the key factors affecting PD/A process from the aspects of pH, carbon source, salinity and heavy metals. Meanwhile, the control strategies of realizing rapid enrichment and good coordination of core functional flora in PD/A process are put forward. Then, a variety of derivative processes developed from PD/A process are summarized, and the research prospects of these derivative processes are analyzed from the aspects of process stability, economy and controllability. Finally, the research focus of PD/A process in the future is prospected, that is, the use of metagenomic technology to identify the resistance formation mechanism of PD/A process under adverse habitat stress is beneficial to the practical engineering application of mainstream Anammox process in the future. What's more, it is believed that coupling with the existing mature biological denitrification process under the background of carbon peaking and carbon neutrality to realize the economical, efficient and standard treatment of various wastewaters will be a key research direction of PD/A process in the future.

Coupling reinforced electrostatic-fabric integrated precipitator has a promising prospect in the field of coal-fired industrial boilers. The removal performance of coupling reinforced electrostatic-fabric integrated precipitator for different water content and its operational performance were experimentally investigated based on a pilot-scale experimental system. The experimental results showed that the bulk density first decreased and then increased with increasing water content, with valley value at water content of 0.65%. The penetration windows of bag filter distributed at different particle size with water content less than 0.65%, and disappeared with the water content higher than 0.65%. With the water content increasing to 0.65%, the total dust mass concentrations, final pressure drop and the total energy consumption decreased and the collection efficiency increased. The final pressure drop was reduced from 335Pa to 276Pa, with reduction of 17.61%, when the water content rose from 0.31% to 0.65%. However, the total performance became bad with the water content larger than 0.65%. Furthermore, the quality factor was used to comprehensively evaluate the total performance of the coupling reinforced electrostatic-fabric integrated precipitator. It was shown that the quality factor increased and decreased with the increase of water content, with the peak value reaching around 0.64%—0.65%. In summary, the performance of the coupling reinforced electrostatic-fabric integrated precipitator can be enhanced by increasing the water content of the fly ash within certain range, which can provide theoretical guidance for performance optimization of coupling reinforced electrostatic-fabric integrated precipitator.

According to "Montreal Protocol on Substances that Deplete the Ozone Layer", waste refrigerants will be phased out and destroyed due to their greenhouse effect and ecological hazards. At present, there is no efficient and low-cost method to treat waste refrigerant. We propose a new strategy for the photocatalytic treatment of waste refrigerant. BiPO₄/GA aerogels were prepared, which showed excellent adsorption capacity of graphene and efficient photocatalytic capacity of BiPO₄. The rapid adsorption and complete mineralization of pollutants were realized. The process of photocatalytic degradation of typical refrigerant tetrafluoroethane (CH₂FCF₃, R134a) was monitored online by in situ infrared spectroscopy. The process of bond breaking and complete degradation of R134a was analyzed. It was clear that the final product of photocatalytic degradation of R134a was HF and CO₂. The results showed that R134a could be completely mineralized and decomposed under the photocatalysis of BiPO₄/GA aerogel. The research provided an effective way to degrade waste refrigerants, and the application of in-situ infrared spectra would also be a reliable method for monitoring the decomposition process of waste refrigerants.

High salinity in textile wastewater limited the application of biological method in textile wastewater. Isolation of halophilic microorganisms is important for improving the treatment efficiency of high salinity textile wastewater. A strain was isolated from active sludge of textile wastewater, which can decolorize metanil yellow. The bacteria were identified by 16S rDNA. The degradation mechanism was analyzed. The results showed the bacteria had the highest homology with Exiguobaterium strain ACCC11618 and belong to the genus. At 5% salinity, more than 95% metanil yellow was decolorized by S2 within 8h. The optimum decolorization condition was 5% salinity, pH 7, at 30℃, and yeast powder as carbon source. Azo reductase and NADH-DCIP are the main degrading enzymes. Salinity inhibits the activity of these two enzymes. The azo bond of metanil yellow was symmetrically broken into 4-aminobenzene sulfonic acid and p-aminobenzidine, which further degraded into diphenylamine, aniline, and 2-heptanone oxime. The toxicity was decreased after decolorization. The strain could decolorize metanil yellow at different concentrations, which showed good application potential. This study is expected to provide species resources and theoretical basis for treatment high salinity textile wastewater.

With the development of society and urban expansion, the disposal pressure of sewage sludge and waste plastics is increasing, while pyrolysis has received widespread attention as a means of resourceful disposal of organic solid waste. In this paper, the effects of temperature and PVC on the distribution of the three-phase products of sludge pyrolysis and their properties were investigated by conducting co-pyrolysis experiments of sewage sludge (SS) and waste polyvinyl chloride plastic (PVC) at 500—900℃. The results showed that with increasing temperature the yield of biochar decreased while the yield of bio-gas increased, and the yield of bio-oil decreased after the first increasing. Meanwhile, the content of CH₄ and CO in bio-gas increased while the content of CO₂ decreased. The carbon number of organic matter in bio-oil decreased with increasing proportion of hydrocarbon and aromatic organic matter increased. The pore structure of biochar surface became irregular and the functional groups decreased. Compared with sludge pyrolysis alone, the addition of PVC increased the yield of bio-gas while decreasing the yield of biochar, and the production of bio-oil would be suppressed at higher temperatures. Furthermore, the added PVC was benefit to improve the quality of bio-gas and increase the content of heavy components bio-oil at high temperature, and enrich the oxygen-containing functional groups of biochar with increasing surface irregularity.

Biogas, typically containing around 60% CH₄ and 40% CO₂, can be used as feedstock in chemical looping reforming (CLR) process. In our previous work, a Ni-based oxygen carrier (OC) using high-alumina firebrick as support has shown excellent performance of complete CH₄ and CO₂ conversion of biogas, thus resulting in high H₂ and CO yield in CLR. Nonetheless, that work also found that the presence of H₂S in biogas can poison the OC and then leads to decrease of the OC reactivity. Based on some literatures, tungsten is promising of lessening the sulfur poisoning on catalysts. In the present work, tungsten was used to decorate the Ni oxygen carrier and the impregnating sequence of Ni and W in the firebrick was changed to study the effects on the OC performance. An 1000μL/L H₂S was mixed with the biogas (the ratio of CH₄/CO₂ was 3/2) and experiments were carried out in a batch fluidized bed reactor under various reacting conditions. It is found that the W-decoration can lower catalytic activity of the oxygen carrier, and the sequence of Ni and W impregnation can also impact the reforming performance. In the case of no H₂S mixing, the OC-Ni-W (first with Ni impregnation, then W impregnation) oxygen carrier has better catalytic performance as compared to OC-Ni=W (Ni, W simultaneous impregnation) and OC-W-Ni (first W then Ni). With the presence of 1000μL/L H₂S, the OC-Ni-W has higher CO and H₂ yield as compared to OC-W-Ni and OC-Ni=W.

To investigate the effect of electrochemistry on scaling and corrosion of carbon steel materials in circulating cooling water systems, an electrochemical treatment system with a Ti/RuO₂ anode and a Ti mesh cathode as the core was constructed, and coupled with a rotating corrosion rate meter and a circulating cooling water dynamic simulation system, respectively. The parameters of the electrochemical system were first optimized by the descaling effect and current efficiency. The experimental results showed that 15V and 120min treatment time were the optimum electrochemical treatment parameters. The results with electrochemical coupling rotary corrosion rate meter indicated that electrochemical embedding can reduce the rate of carbon steel surface scale deposition for different hardness of water. XRD and SEM analyses found that the calcite-dominated to aragonite-dominated crystalline form of scale on the surface of carbon steel was transformed. However, electrochemical embedding in low-hardness solutions can significantly increase the corrosion rate of carbon steel, while in hard water with high hard water quality the surface of carbon steel can form a uniform and dense layer of Fe₃O₄. The corrosion rate of carbon steel was reduced from 0.60mm/a and 0.54mm/a to 0.47mm/a and 0.32mm/a, respectively. The results of the electrochemical coupled circulating cooling water dynamic simulation device showed that the fouling thermal resistance of the circulating cooling water simulation system was significantly reduced after embedding the electrochemical module. After data analysis, when the water quality was low hardness water, the carbon steel corrosion rate increased after embedding the electrochemical system, while when the water quality was high hardness water, the corrosion rate was reduced from 0.12mm/a, 0.15mm/a to 0.10mm/a, 0.13 mm/a, respectively. It was shown that electrochemical embedding can significantly reduce the rate of scale deposition in the system, but pose the risk of increased corrosion when the water hardness was low, providing a reference for the safe promotion of subsequent electrochemical technology.

Biphasic solvents have a promising application prospect own to the lower regeneration energy consumption character. However, complex screening works usually need to be done when new physical-chemical biphasic solvents were developed. In order to solve this problem, this paper firstly selected different water-soluble physical solvents and amino groups amines, and then carried out absorption, phase separation and regeneration experiments in turn using a small experimental device to explore the effects of water-soluble and amino groups on the performance of biphasic solvent. It was found that the water solubility of the physical solvent had no obvious regular relationship with the absorption and regeneration performance of the solution, but the biphasic solvent composed of hydrophobic physical solvent had lower rich phase ratio and higher rich phase CO₂ ratio. The solution containing only tertiary amino group had good regeneration performance, but the absorption rate increased slightly and the absorption load decreased compared with the aqueous amine solution. The type of amino group had little effect on the phase separation performance, but the number of amino groups affected the change range of rich phase ratio.

The biochars were prepared by pyrolysis of food waste digestate residues at five temperatures (400℃, 500℃, 600℃, 700℃ and 800℃), and their morphological characteristics, pore structures and surface functional groups were analyzed to investigate the effect of adsorption of ciprofloxacin hydrochloride (CIP) in aqueous solution. The results showed that the biochar prepared by pyrolysis at 700℃ (DR-700) became loose and porous with rich surface functional groups, better pore structure and microstructure. DR-700 had the best adsorption effect on CIP among the five biochars and could reach 95.09% removal of CIP, which could be used as a good adsorption material. The adsorption of CIP on DR-700 was more in line with the pseudo-first-order kinetic and Freundlich isotherm models, which indicated that physical adsorption might be the main mechanism of CIP adsorption on DR-700, and was more attributed to the rich surface area. In contrast, the simultaneous chemisorption might be due to cation exchange interactions, electrostatic interactions, π-π interactions, hydrophobic and hydrogen bonding interactions. Therefore, the use of biochar prepared by food waste digestate residues had a good adsorption and purification effect on CIP in aqueous solution, which not only provided a new material for the low-cost treatment of antibiotic wastewater, but also provided a new solution to solve the problem of resource utilization of anaerobic fermentation end products of food waste, and had good application potential.

The content of Cr and V in the crude tungstate solution obtained in the recycling process of waste cemented carbide is easy to exceed the standard. Because Cr, V and W have very similar properties of aqueous solution, the removal of chromium and vanadium from the crude tungstate solution has always been a technical problem. In this paper, the thermodynamic analysis and research on the process of removing chromium and vanadium from the crude sodium tungstate solution by ferrous salt precipitation method were carried out. The Eh-pH diagrams of Cr-Fe-H₂O System and V-Fe-H₂O system at 298K and the thermodynamic equilibrium diagrams of Cr⁶⁺-Fe³⁺-V⁵⁺-H₂O system and Cr³⁺-Fe²⁺-Fe³⁺-V⁵⁺-H₂O system at 298K were drawn, respectively. Thermodynamic analysis results showed that Cr(Ⅵ) in crude sodium tungstate solution could be reduced by Fe²⁺or Fe(OH)₂ precipitation in both acidic and alkaline systems, and V(Ⅴ) would react with Fe²⁺ or Fe(OH)₂ to form Fe(VO₃)₂ precipitation. In Cr³⁺-Fe²⁺-Fe³⁺-V⁵⁺-H₂O system, there was a stable coprecipitation zone of Fe(VO₃)₂+Fe(OH)₃+Cr(OH)₃+Fe(OH)₂, which provided thermodynamic feasibility for the simultaneous removal of chromium and vanadium by ferrous salt precipitation method, and obtained the control range of the best conditions of precipitation method. The experimental results indicated that when the pH value of the solution was controlled to be 9 and ferrous sulfate precipitant was added with n(Fe²⁺)∶n(V+Cr)=15∶1, the chromium removal rate of crude sodium tungstate solution was as high as 99.85%, the vanadium removal rate was 95.05% and the tungsten loss rate was only 0.33%. The experimental effect was basically consistent with the thermodynamic analysis conclusion. The SEM-EDS analysis results of the filter residue further confirmed the technical feasibility of Fe-Cr-V coprecipitation.

Anaerobic soluble microbial products (SMP) are widespread in the deep-water environment and could migrate to the upper water by water disturbance processes. The physicochemical properties of anaerobic SMP would be altered during migration by various abiotic transformation processes, such as photo irradiation and redox processes, which would further change its photochemical activity. Herein, anaerobic SMP extracted from anaerobic microorganisms (An-SMP) and that from Shewanella oneidensis (S-SMP) were modified by photo irradiation and redox processes for 48h to evaluate the effects of these abiotic modifications on the photochemical activity of anaerobic SMP. The results of the characterization showed that the aromaticity, humification degree, and molecular weight of the original An-SMP were higher than those of S-SMP. The UV absorbance, aromaticity, degree of humification, and aromatic C\stackrel{}{̿}C structure of both of SMP decreased after the photo-modification, while hydrophilic oxygen-containing functional groups increased. After the redox-modification process, the hyperchromic effect of both of SMP absorbance was observed, as well as the increase of humification degree and the conversion of protein-like substances to humic substances. Compared to photo-modification, redox-modification showed more significant effects on the photochemical properties of SMP. Furthermore, the photo-transformation of 17α-ethinylestradiol (EE2) was promoted by the SMP, and the redox-modified SMP exhibited superior photochemical properties than that of photo-modified SMP. The mechanism study indicated that the active oxygen substances were responsible for the photolysis of EE2, especially the ³SMP^* and ·OH. This study provided a theoretical basis to clarify the effect of abiotic transformation processes on the photo-transformation of organic pollutants mediated by SMP in natural water.

Modified iron-rich attapulgite was obtained by hydrochloric acid activation and Fe₃O₄ composite modification. The effect of O₂/H₂O/SO₂ on the adsorption of typical semi-volatile heavy metal PbCl₂ vapor was investigated in a high-temperature furnace. Meanwhile, the distribution and morphology of lead species in the adsorption products were analyzed. FTIR, BET, XRD and XPS were used to investigate the adsorption mechanism. The results showed that acid activation increased the proportion of surface-active sites by decomposing the impurities in raw ore. The dual active adsorption sites formed from the composite modification by iron-based oxides and attapulgite surface lattice oxygen significantly increased the adsorption capacity of PbCl₂. When the flue gas contained 20% O₂, 5% H₂O and 400mL/m³ SO₂, the PbCl₂ adsorption capacity of the modified attapulgite was significantly higher than that of the original attapulgite. The highest adsorption capacities of 70.42mg/g, 76.63mg/g and 86.21mg/g were achieved in Fe/HFP₂ sample with a loading mass ratio of 1∶2, respectively, better than kaolinite. Furthermore, the content of stable distributed Pb in the adsorption products using modified attapulgite under these atmospheres was higher than that of kaolinite, indicating the adsorption products were more stable.