Bioremediation has been a research focus on site remediation contaminated by petroleum hydrocarbon, and so far, much experimental and theoretical knowledge has been gained on it. However, the current researches are conducted in optimal temperature environment. In fact, bioremediation often undergoes mid-low temperature period in site when physiological characteristics will change for both indigenous and exogenous microorganisms. Due to low cell activity, the mid-low temperature period in the remediation process has always been overlooked, resulting in the use of conventional technology to remediate contaminated sites with poor efficiency and the lack of pertinence. In this paper, the research status of microorganisms degrading petroleum hydrocarbons at low temperature was summarized, focusing on low-temperature metabolic mechanism and main metabolic pathways of three kinds of typical petroleum hydrocarbons, namely, long-chain alkane, benzologue and polycyclic aromatic hydrocarbons. On this basis, the microscopic changes of cell physiological-biochemical characteristics under different temperature conditions have been further analyzed from the following four different aspects: fatty acid composition, protein expression in low temperature, the synthesis of specific protein, and adaptability of the enzymes structure. It was shown that the unique cold-adapted mechanism of low-temperature microorganisms determines its unique low-temperature degradation characteristics and consequently becomes the core of low-temperature remediation technology. In brief, low temperature bioremediation should deserve adequate attention. For one thing, the bioremediation efficiency can be effectively improved by making full and reasonable use of controlled restoration in lengthy low-temperature period to improve the utilization rate of nutrient salt; and for the other, it will be a feasible development direction to study the cell metabolism and cold-adapted mechanisms to guide the implementation of low-temperature bioremediation.

Petrochemical industry is one of the core industries in China, whilst it is also a main source of environmental pollutions. Since the nation’s environmental situations become severer together with the fact that more and more environmental regulations have been installed, the effective remediation towards the typical petrochemical-related contaminations is now a priority topic. As a recently-developed class of material, metal-organic frameworks(MOF) have exhibited promising application potentials for environmental remediation in petrochemical industries. The materials could work as effective adsorbents, functional membranes as well as catalytic candidates to remove/separate/degrade petrochemical pollutants. This article reviews the relevant applications in this field, analyzes the most significant work, and finally discusses the future perspectives for the further development of MOF materials. Overall, MOF materials have exhibited better structural features and application performance. It shall work favorably as adsorbents, membranes and catalysts in the environmental areas of petrochemical industries in the future.

As the most advanced evaporative crystallization technology, mechanical vapor recompression(MVR) has been widely concerned and applied. In this paper, an advanced MVR evaporative crystallization drying system combined with the superheated steam drying technology was proposed. A mathematical model has been developed using EES software. The effects of the feed concentration(c₀), flash pressure(p_flash), circulation ratio(CR), heat exchanger temperature difference(?T_mhex) on the compressor work(W_comp), coefficient of performance(COP), the maximum value moisture content of salt crystals in downcomer(ω) and heat exchanger parameter(UA) were studied in detail by using system simulation. The results showed that, compared with the conventional system, the MVR system coupled with superheated steam drying technology obtained higher COP, lower W_comp, and could get dry crystal salts. With the increase of circulation ratio CR, the compressor pressure ratio π decreased, which is beneficial to improve COP and reduce W_comp, but at the same time, the heat exchanger parameter UA_mhex and the equipment cost will increase. The variation of COP with p_flash was influenced by the CR. As the CR was under a lower value, the COP increased with the increase of p_flash, and once CR exceeded a certain value, the COP increased first and then decreased with the rising of p_flash. There existed a maximum value when the p_flash was among 40—50kPa. The ω increased significantly with the increase of the c₀. The ?T_mhex has obvious effect on the performance of MVR system, and the COP decreases by 5.6%, W_comp increases by 5.8%, UA_mhex decreases by 14.4%, and ω increases by 1.7%, respectively, per unit increase in?T_mhex.

Multi-orifice plate is often used as a throttling or flow measuring component in pipelines, which has obvious advantages in reducing pipe vibration, flow noise and flow pressure loss in comparison with the conventional single-orifice plate. The structural factors being related with the pressure loss coefficient of multi-orifice plates are mainly the equivalent diameter ratio of orifice to pipe, the orifice number and the orifice thickness. The influence of equivalent diameter ratios had been well identified, while the influences of orifice number and orifice thickness are still unclear. In this paper, the effects of changing orifice number or orifice thickness on the pressure loss coefficient of stable region for multi-orifice plates, in which the orifices were arranged in regular triangle layout, were studied by numerical simulation. The results showed that under the same orifice thickness, the pressure loss coefficient decreases rapidly at first and then tends to be a constant with the increase of orifice numbers. The critical orifice number for reaching a stable pressure loss coefficient is declined with the decrease in pipe diameters, while the relative orifice thicknesses corresponding to the critical orifice numbers are close to 0.50 under different pipe diameter. Under the same orifice number, as the relative orifice thickness increases, the pressure loss coefficient decreases rapidly at first and then tends to be a stable value. The critical relative orifice thickness that makes the pressure loss coefficient stable is in the range of 0.5 to 1.0, which decreases as the orifice number increases. Under the same relative orifice thickness, for thin orifice plates the pressure loss coefficient decreases first and then increases with the increase in orifice number, while for thick orifice plates, it increases monotonously with the increase in orifice number. It revealed that, in addition to the equivalent diameter ratio, both the orifice number and the relative orifice thickness should be considered in the pressure loss coefficient correlation for multi-orifice plates because of their considerable influences.

Deep eutectic solvents (DESs) are widely used in many fields, especially in the field of gas purification. To investigate the synergistic absorption performance of the DESs with high absorption capacity and strong regenerative capacity to absorbing SO₂ and NO in flue gas, Fe(Ⅱ)EG-TBAB DESs was prepared by using ferrous chloride (FeCl₂), ethylene glycol (EG) and tetrabutyl ammonium bromide (TBAB). Effect of temperature, residence time, oxygen partial pressure and concentration of FeCl₂ on the removal of NO in the flue gas were investigated. The inlet and outlet concentration of SO₂ and NO at the spray scrubber reactor were measured using online flue gas analyzer to characterized desulfurization and denitrification performance of Fe(Ⅱ)EG-TBAB DESs. The results showed that under the condition of 0.1mol/L FeCl₂, temperature of 50℃, the oxygen partial pressure of 5%, Fe(Ⅱ)EG-TBAB DESs showed the best desulfurization and denitrification performance. The presence of H₂O and O₂ in the flue gas, SO₂ gas can form \mathrm{H}\mathrm{S}{\mathrm{O}}_{\mathrm{3}}^{-}^{and \mathrm{H}\mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{-}, to further promote the absorption of NO in Fe(Ⅱ)EG-TBAB DESs, resulting in the formation of Fe(Ⅱ)EG-TBAB(NO). After sixth absorption-desorption cycles, the desulfurization and denitrification capacity of the samples have no obviously changed and show good desulfurization and denitrification stability.}

Under the high temperature and high pressure environment, aluminum sheets with special shapes through wire-electrode cutting were embedded on the surface of the resin. Corroded by CuCl₂ solution and modified by thermostatic water bath of stearic acid anhydrous ethanol solution, the composite surface with the coexistence of hydrophilic zone and hydrophobic zone was obtained. High speed camera was used to record the drop dynamic process imping on the plate with alternating hydrophobic and hydrophilic stripes. The experiment results showed that when the plate was placed horizontally, the spreading processes on the composite surface and on a single wettability surface were similar, but the shrinkage behaviors subsequently were significantly different. The height difference of liquid film was caused by alternating hydrophobic and hydrophilic stripes when the droplet shrinking on the composite surface. In the case of droplet impacting on inclined hydrophilic and hydrophobic composite surface: The higher the velocity of the droplet impacting on the composite surface was, the larger the displacement was, and the droplet with excessive speed would not be captured by the plate with a length of 20mm. When the velocity was set to a certain value, the droplet could across more hydrophobic regions with a smaller Oh number. When other parameters kept being constant, the smaller the ratio H of the droplet radius r to the interval width w was, the more easily the droplet was captured by the functional surface.

This paper proposed a screw turbine-heat pump (st-hp) cogeneration heat supply method to exploit the residual heat and pressure utilization potential of the steam-water system to achieve better energy-saving effect and higher heating power. Based on the second law of thermodynamics and the theory of entranspy, the exergy and entranspy analysis of the main newly added components under variable operating conditions were carried out. Using the IPC exhausting, the heating capacity was improved by means of “extra pressure for electric and residual heat for heating”. Absorption heat exchanger located in the thermal station was designed by algorithm to enlarge the temperature difference of the network water and the model was verified. A 600MW unit was used as an example to analyze the exergy and entranspy efficiency of new main heating elements in the power plant side under variable operating conditions using Ebsilon software. The results showed that st-hp system can not only increase the heat capacity of the municipal heat network by 50% without enlarging output of the boiler, but also meet the part demand of the plant. The energy-saving research of absorption heat pump and peak heater shall focus on improving the perfection of thermal cycle to reduce exergy loss. Screw turbine and peak heater should focus on improving the coordinative degree of working fluid velocity field and temperature field in heat transfer process. The operating conditions have a great influence on the thermal economy of the unit. When the thermal load is different, the minimum and maximum values of coal consumption for power generation are -5g/(kW·h) and 22.97g/(kW·h) respectively.

With the development of domestic petroleum exploitation, the water cut of produced liquid is up to 70%—90%, and the energy consumption of gathering and transportation in oilfields is greatly increased, which makes low-temperature transportation process widely used. However, a series of flow assurance problems caused by the wall sticking of gelled crude oil have attracted extensive attention of researchers at home and abroad. This paper mainly expounds the research progress of wall sticking at home and abroad, summarizes and analyses the influencing factors and related research results of wall sticking law at present, introduces the main experimental equipment and research methods of wall sticking law, and summarizes the experimental results of domestic and foreign scholars. Based on the above research results, the macro-rule of wall sticking, the influence of physical properties and composition of crude oil and the influence of gelled crude oil are summarized, and wall sticking are deemed the result of the combined action of kinetics and thermodynamics. In particular, the discriminant method and empirical regression formula for wall sticking temperature are put forward. Finally, suggestions and directions for further research on wall sticking are given. This will be of great significance to alleviate and control the wall sticking problem of gelled crude oil and ensure the safe operation of pipelines in the future.

Fuel ethanol conversion by lignocellulose generally requires raw materials pretreatment, enzymatic hydrolysis and fermentation processes. The efficiency of direct enzymatic hydrolysis of cellulosic biomass is very low due to the complex chemical structure of the lignocellulosic materials. Generally, appropriate pretreatment is necessary before enzymatic hydrolysis is carried out in order to break the dense structure of substrate, increase the surface area of the cellulose and improve the subsequent cellulase accessibility. Based on the analysis of common pretreatment techniques for lignocellulose, this paper focused on three relatively efficient pretreatment techniques: microwave-assisted ionic liquid pretreatment, two-stage deep eutectic solvents pretreatment and FeCl₃ pretreatment. Their strengths and weaknesses were analyzed. Microwave-assisted ionic liquid pretreatment can effectively deconstruct lignin and hemicellulose, destroy the crystalline region of cellulose, and facilitate subsequent enzymatic hydrolysis. However, microwave heating process will decompose ionic liquid and carbonize some substrates, which will reduce the effect of pretreatment. Two-stage DES pretreatment can effectively improve the enzymatic hydrolysis efficiency, but the residual DES in the raw material after pretreatment may inhibit the cellulase and microorganisms in the subsequent reaction. FeCl₃ pretreatment can effectively destroy the ether bond and partial ester bond between lignin and carbohydrate, and remove hemicellulose from the substrate, while less degradation of lignin and cellulose. Finally, the paper prospected the development trend of lignocellulose pretreatment technology.

The fusion characteristics of twenty-three synthetic ashes with the same acidic to basic ratio (R_a/b) of 0.82 but with varying acidic oxides including Na₂O, CaO, MgO, and Fe₂O₃ were investigated. The synthetic ashes were prepared in accordance with the R_a/b of Zhundong coal ash, and then ashed in a muffle furnace at 815℃. These ashes were then subjected to ash fusion analyzer, SEM-EDS and XRD analysis for their fusion temperatures (AFTs), microstructures and mineralogical composition. The results showed that deformation temperature (DT), softening temperature (ST), hemispherical temperature (HT) and flow temperature (FT) of the synthetic ash decreased from 1225℃, 1233℃, 1255℃ and 1297℃, respectively, to 1162°C, 1174℃, 1181℃ and 1189℃ as Na₂O content increased from 4% to 12%, indicating that Na₂O played a significant role in decreasing AFTs. Likewise, as the CaO and MgO contents increased, DT, ST and HT were decreased, while FT was decreased first but increased afterwards, indicating that the effect of CaO and MgO addition on AFTs were non-linear. Furthermore, significant changes in AFTs were not observed as Fe₂O₃ mass fraction varied from 5% to 30%, with the exception that FT increased from 1215℃ to 1308℃. SEM-EDS and XRD analysis revealed that the variation in fusion characteristics of the synthetic ashes were mainly attributed to the proportion of refractory minerals mainly SiO₂ and CaAl₂Si₂O₈ and the fluxing minerals such as CaMgSi₂O₆ and NaAlSiO₄, as well as the degree of eutectic formation between Na- and Ca- bearing minerals. A comprehensive comparison between the measured AFTs and their corresponding basic oxide contents showed that DT was mainly affected by the overall amount of alkaline-earth metal (CaO and MgO) and Na₂O content, whereas FT was closely associated with Na₂O and Fe₂O contents in the synthetic ash.

The change of conjugated diene and conjugated triene in the oxidation process of Jatropha biodiesel resulted in the increase of absorbance at 230nm and the decrease of absorbance at 270nm with increasing oxidation time. Four models of linearity, exponential, logarithm and power of biodiesel acid value and the UV absorbance were established in order to quickly detect the degree of oxidative degradation of biodiesel. The leave-one-out cross-validation showed that the predicted root mean square error of the linear model was the smallest, and the correlation between the predicted value and the measured value was the highest. The linear equations of acid value and absorbance were established by least squares method and the model was verified. The results showed that the fitting goodness R² of the fitting equation was 0.987, which indicated that the fitting model had better fitting effect; the goodness of fit between the measured value and the predicted value in the model verification was 0.980; the maximum relative error of the sample was 5.27%, and the model had high accuracy and precision. This method can be used instead of titration to quickly and accurately predict the acid value to characterize the degree of oxidative degradation.

Compared with traditional catalysts, ionic liquid (IL) catalysts have the advantages of easy separation and recycling，which renders them great potential in the polymerization of α-olefins. This article introduces the basic properties of ILs and describes the reaction mechanism of α-olefin polymerization with ILs as catalyst. Then, the applications of Lewis acid ILs in the α-olefin polymerization are reviewed. The catalytic activity and product properties are analyzed. In addition, the researches of novel liquid coordination complexes (LCCs) also have been summarized. From the reported results, high conversions have been realized with ILs and LCCs as catalysts. However, the selectivity needs to be further improved with lots of experimental investigations. Although ILs and LCCs catalysts cannot replace the traditional catalysts at present, they have shown great application prospect，and will be one hotspot of future researches.

Semiconductor WO₃ possesses a small band gap, good stability, and strong absorption in visible light region. Thus, it exhibits a wide range of applications in photocatalysis and photoelectrocatalysis. However, there are still some problems for single WO₃ thin films, such as high photogenerated electron-hole recombination rate, low photoelectrocatalytic activity and low energy conversion efficiency. In this paper, recent research progress on the photoelectrocatalytic properties of WO₃ thin film is reviewed from two aspects of improvement methods and applications. Regarding the former, methods of construction of ordered nanostructures, ion doping and surface modification were summarized. At the same time, the applications of WO₃ thin films as photoelectrodes in water decomposition for hydrogen production, photoelectrocatalytic reduction of CO₂ and degradation of organic pollutants were concluded. The problems of WO₃ thin films in photoelectrocatalytic process were put forward. It is suggested that the construction of ordered nanoheterojunctions is an effective method to improve the photoelectrocatalytic activity of the WO₃ thin films. The large-scale preparation of WO₃ thin film photoelectrodes, the use of cheap cocatalysts, the stability and corrosion resistance of the photoelectrodes are the difficult problems to be solved in its practical applications.

Raney alloy catalysts typically appear as powder in catalytic reactions, which cannot be used in fixed-bed reactor due to the shortcomings of flammability and inconvenient to operation. In order to expand the applications of the Raney alloy catalysts, molding becomes the focus of recent research of these catalysts. Conventional molding and calcining of the catalysts easily lead to considerable sintering of the catalyst particles, low metal utilization and decreased activity. This article introduces a method for preparing a new alloy composite catalyst, which can accomplish the preparation and molding of the catalyst in one step. A series of physical and chemical characterizations were carried out for the new Raney alloy catalyst and it was found that the catalyst has a loose structure, with extensive channels with secondary ones. The high temperature didn’t cause the metal particles to sinter and the size of the active metal particle was about 50nm, uniformly dispersed in the catalyst. The catalyst performance in the hydrogenation reaction was evaluated. Under the optimal reaction conditions of temperature 250℃, pressure 3.0MPa, n(H₂): n(ethyl acetate) 37 and LHSV 0.25h^-1, the new complex catalyst has a high activity two times as the conventional one.

Three kinds of novel hyperbranched salicylaldimine ligands and nickel catalysts were prepared with 1.0G hyperbranched macromolecule, 3-substituted salicylicaldehyde and NiCl₂·6H₂O as the raw materials, and the structures were fully characterized by FTIR, ¹H NMR, UV, ESI-MS and ICP-MS. The effect of ligand steric hindrance, solvent, co-catalyst and reaction conditions on cayalytic property of ethylene oligomerization was investigated. The result showed that the ligand steric hindrance had a significant effect on catalytic property. Under the optimum reaction conditions, the catalytic activity could reach up to 2.81×10⁵g/(mol Ni·h) and the selectivity of high carbon olefins (C₁₀₊) was 34.28% when toluene was used as solvent and MAO as co-catalyst. In addition, the mechanism of catalytic ethylene oligomerization was studied on the base of the evaluation of catalytic performance of hyperbranched salicylaldehyde nickel catalysts.

The synthesis conditions and catalytic properties of ZSM-35 zeolites with different SiO₂/Al₂O₃ ratios were investigated. ZSM-35 zeolite with SiO₂/Al₂O₃ ratios in the range of 30 to 40 can be hydrothermal synthesized with various organic amines (ethylenediamine, cyclohexamine and n-butylamine) as templates. The suitable crystallization temperature in the ethylenediamine template system was 130-160℃. With ethylenediamine and n-butylamine as templates, ZSM-5 and quartz phase were easily formed when SiO₂/Al₂O₃ ratio was 58. Binderless ZSM-35 zeolite with relatively high SiO₂/Al₂O₃ ratio of 58 can be synthesized with cyclohexamine as template. When SiO₂/Al₂O₃ ratio was 72, it was difficult to synthesize pure ZSM-35 zeolite in ethylenediamine, cyclohexylamine and n-butylamine templates, and heterocrystals were also produced. In xylene isomerization reaction, ZSM-35 zeolite showed better p-xylene selectivity and lower xylene loss than ZSM-5 zeolite.

The supported catalyst of H₃PW₁₂O₄₀/acid modified diatomite was prepared by using the acid modified diatomite as carrier and Keggin type phosphotungstic acid as active constituents. The catalyst was characterized by FTIR, XRD, SEM, EDS and N₂-TPD. The results showed that acid modification obviously increased the BET specific surface area and the pore structure of diatomite. Phosphotungstic acid kept Keggin type after distributed on the surface or inside the pore of acid modified diatomite. The synthesis of n-butyl acetate from acetic acid with n-butanol using the H₃PW₁₂O₄₀/acid modified diatomite as catalyst was studied. The optimum reaction conditions were optimized via orthogonal tests, which was as follows: the mass percentage of 40% H₃PW₁₂O₄₀/acid modified diatomite of 1.1%, based on the total reactants, the mole ratio of acetic acid to n-butanol of 1∶3, reaction temperature 125℃ and reaction time 2.0h, under which the yield of n-butyl acetate was 98.1%. H₃PW₁₂O₄₀/acid modified diatomite catalyst could be reused for 5 times and the yield of n-butyl acetate was still above 86.1%. The catalyst for the esterification reaction has many advantages such as easy preparation, low cost, high activity, simple post-treatment, non-corrosive to equipment and no pollution.

Pyrolysis is an important utilization technology for coal, but the by-product tar is extremely harmful, and catalytic upgrading is one of the efficient and clean utilization methods of coal tar. In this paper, the catalytic pyrolysis experiments of ash-free Xuzhou bituminous coal were carried out in a tube furnace reactor on Fe/CaO catalyst prepared by sol-gel method. The results showed that Fe/CaO catalyst could promote the production of pyrolysis gas significantly, and the yields of CO₂, CO and CH₄ increased gradually. Fe/CaO catalyst promoted the catalytic cracking of liquid product, resulting in a significant decrease in liquid yield. Fe/CaO catalyst promoted the conversion of polycyclic aromatic hydrocarbons to aliphatic hydrocarbons and light aromatics. In addition, the production of naphthalene compounds was also promoted by Fe/CaO catalyst. The contents of bicyclic compounds in tar increased while that of the tricyclic and polycyclic compounds decreased, the molecular weight of the tar presented a declining tendency.

CO₂ hydrogenation to light olefins bymethanol synthesis or oxide intermediates, is accomplished through two successive reactions of activation of CO₂ to methanol and methanol conversion to olefins. This route can break the product distribution limitation of Anderson-Schulz-Flory (ASF) via Fischer-Tropsch synthesis and produce light olefins with high selectivity. It is reported that the products from traditional Cu-based composite catalysts mainly include methane and alkanes due to their strong hydrogenation ability during CO₂ hydrogenation. Herein, we report the design and preparation of CuZnTiO₂/(Zn-)SAPO-34 composite catalyst that shows high selectivity for C₂—C₄ olefins (around 60%). The study demonstrates that the acidity of the catalyst has great influence on product distribution, due to the low methanol concentration (＜6%) and high activity of the reverse water gas shift reaction (RWGS) at high temperature during the two-step reaction process. There exists competition between the formation of methane and the tandem reaction with the change of the content of two active components. The increase of the acid content of SAPO-34 can inhibit the formation of methane and promote the tandem reaction. Reduction in acidity of SAPO-34 by Zn promotion also contributes to the formation of light olefins. It is favorable to suppress the secondary hydrogenation reaction of light olefins, by controlling the distance between the two active components.

Spinel catalyst NiFe_1.97-xMn_xPd_0.03O_4-δ was prepared by using a biological template and then was applied for the selective catalytic reduction of NO with hydrogen(H₂-SCR) in a single-tube fix-bed reactor. A series of spinel catalysts was obtained by doping Mn with different molar ratio of Mn to Ni. The catalysts were characterized by X-ray diffraction（XRD）, field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy（FTIR）, NH₃ temperature-programmed desorption (NH₃-TPD) and H₂ temperature-programmed reduction (H₂-TPR). The results indicated that the catalysts doped with suitable amount of Mn had significantly improved the dispersion of the active specie Pd, the total acid content on the catalyst surface and the ability to oxidation, leading to enhanced de-NO_xperformance of NiFe_1.97Pd_0.03O_4-δcatalyst at low temperature and a broadened active temperature window. Within the scope of the experiments, the NO conversion of NiFe_1.92Mn_0.05Pd_0.03O_4-δcatalyst was up to 95% at 150℃, and maintained above 90% at 150—200℃.

Increasing the specific heat capacity of the molten salt material can effectively enhance its heat storage capacity, reduce the area of the heat storage system and heat loss, and thus reduce the heat storage cost. It is a research hotspot in the field of medium and high temperature energy storage in recent years. In this paper, the research progress on the enhancement of specific heat capacity of molten salt heat transfer and storage materials in recent years is reviewed from the aspects of necessity, method and mechanism of strengthening molten salt heat storage materials. The methods of adding soluble additives and doped heterogeneous nanoparticles to form nanofluids to enhance the specific heat capacity of molten salt and their current problems are elaborated in detail. The preparation methods of molten salt nanofluids, heterogeneous nanoparticle systems, strengthening effects and the mechanism are emphatically discussed. In addition, the current shortcomings of using nanofluids to strengthen the specific heat capacity of molten salt heat storage materials are pointed out as insufficient research system, poor suspension stability and imperfect specific heat capacity strengthening mechanism. And the future development direction of molten salt nanofluid are prospected, including the development of multi-system molten salt nanofluids, the multi-aspect revealing of specific heat capacity strengthening mechanism and the multi-method measurement of molten salt nanofluid physical properties.

Boron is an essential trace element in living organisms, but excessive intake of boron can endanger the growth and development of plants and animals. In the existing boron removal technology, reverse osmosis membrane is considered as one of the most promising platforms for boron removal. Due to the small molecular diameter of the boric acid molecule and the absence of charge, the removal of boron by the reverse osmosis membrane still cannot meet the actual requirements. At present, optimizing the structure of reverse osmosis membrane and utilizing the special properties of boric acid are the main ideas for preparing high boron removal reverse osmosis membrane. The development of new membrane materials, optimization of interfacial polymerization processes and physical and chemical modification are effective ways to improve the boron removal performance of reverse osmosis membranes. The trade-off phenomenon of water boron transport is a major obstacle for the preparation of high boron removal reverse osmosis membranes and lacks models for water and boron transport. At the same time, the boric acid molecules have unique physical and chemical properties. The boric acid molecules are beneficial to study the polymer structure of the polyamide reverse osmosis membrane, the transport mechanism of water boron in the membrane and the factors causing the trade-off phenomenon.

Stannosilicate zeolites show excellent catalytic performance in transformation of oxygenated hydrocarbon, hence they are of great industrial application potential. Characterization, synthesis methods, hierarchical stannosilicate zeolites and their applications were reviewed in detail. Various characterization methods (such as XRD, NMR, and EXAFS) are employed to determine the coordination and location of tin atoms in stannosilicate zeolites. Tin-containing zeolites can be prepared by several methods, including hydrothermal crystallization, post-synthesis and dry-gel conversion methods. In basic hydrothermal crystallization process, it is key to match the hydrolysis and crystal growth rates between tin and silicon sources, so as to make Sn atoms efficiently insert into the zeolite framework. Tin-containing zeolite prepared by neutral hydrothermal synthesis method in the presence of fluorine-containing agents is of high crystallinity, but it suffers from the use of toxic fluorine reagent and large size particles. Dry-gel conversion method favors to synthesize highly crystalline stannosilicate zeolites within short time, but it is of poor heat and mass transfer performance. Meanwhile, Sn atoms are also incorporated into the framework of various topological zeolites, yet the Sn species are easily to aggregate. Hierarchical stannosilicate zeolites are synthesized by alkali treatment, hard-template method and soft-template method to improve the accessibility of framework tin atoms. Among them, soft-template approach shows promising prospect, with narrow mesopore distribution and good connection. In addition, framework tin atoms of stannosilicate zeolite tend to interact with oxygen-containing functional groups, which renders them good catalytic performance in Meerwein-Ponndorf-Verley-Oppenauer reaction, glucose isomerization to fructose, the synthesis of lactic acid and tis lactate and Baeyer-Villiger reaction.

The preparation of superhydrophobic surface is one of the hotspots in the field of materials. With the development of research, the principle of superhydrophobic materials is almost clear, and the research for practical has begun to be paid attention to. Simplifying the preparation process, reducing the cost of materials, prolonging the service life and improving the abrasion performance and weather resistance of the surface become the key to the application of superhydrophobic materials. Superhydrophobic materials can be obtained by controlling the composition and morphology of polymers. Among the usual method, phase separation technology is one of the most possible for application because of its simplicity. Although phase separation technology is applied in the field of superhydrophobic surfaces for a long time, there are relatively few special reviews on this technology. This paper summarizes the polymer phase separation technology used for preparing superhydrophobic surfaces, and the future research directions are prospected.

Composite coating materials were prepared by solution blending with poly(vinyl alcohol )(PVA) as raw material, poly(ethylene pyriloxane)(PVP) as modifier and distillers' grains (JZ) as additive. The coated slow-release fertilizers were prepared by coating nitrogen fertilizer.The effects of JZ addition on the properties of composite coating materials and the slow-release properties of coated fertilizers were studied. Experimental results showed that JZ combined with each component hydrogen-bonded noncovalent interactions and had good compatibility. The addition of JZ significantly enhanced thermal stability of composite coating materials. The degradation rate of 120d PUPZ5 composite coating material was 20.11% higher than that without JZ. With the addition of JZ, the mechanical properties of the composite coating materials increased at first but decreased finally. When the mass ratio of JZ and PVA is 15∶100, the mechanical properties of the composite coating materials was 20.75MPa being 528.79% higher than that of composite coating materials without JZ. Moreover, the slow-release fertilizers had good slow release effect, and the release of urea in the slow-release fertilizers could be controlled by adjusting the content of JZ in the composite coating materials.

The alkali reduction treatment of cathode materials for high nickel ternary lithium ion batteries is confined to pure water washing and the effect is limited. There are few reports on ultrasonic cleaning. A new technology of treating cathode materials of high nickel ternary lithium ion batteries by ultrasonic water washing was proposed. LiNi_0.8Co_0.15Al_0.05O₂ (NCA) was the research object and pure water as solvent. The factors affecting the alkali reduction of cathode materials by ultrasonic washing were discussed through orthogonal experiments. The influence of single solid content factor on washing with pure water was compared. The effects of solid content, stirring time, ultrasonic time, frequency and power on alkali reduction of cathode materials for high nickel lithium ion batteries were studied by means of pH, particle size analysis, SEM and electrochemical performance test. The results showed that the treatment effect was the best when solid content was 10% with stirring time of 5min, ultrasonic time of 1min, ultrasonic frequency of 200kHz and ultrasonic power of 100W. pH of cathode material decreased by 12.02%. The particle size distribution was more uniform, the surface morphology of the particles had no obvious influence, and the electrochemical properties of materials were improved. The solid content of washing was 40% in the actual industrial production process.

Nanometer MnO₂-PVA /GP composite electrodes were prepared by a simple coating method using the soluble polyvinyl alcohol and nano-MnO₂ catalyst. The morphology, composition and electrochemical properties on the electrode surfaces were analyzed by FTIR, SEM and cyclic voltammetry(CV). The composite electrodes were fully covered with a smooth PVA surface layer where MnO₂ nanoparticles were tightly embed. The nano-MnO₂ particles were spherical γ-type crystals with the mean diameter of 15—20nm and thus high electrocatalytic activity. The composite electrodes presented a multilayer structures containing graphite paper as substrate electrode, PVA adsorption layer and nano-MnO₂ catalytic region, and had been applied for electrochemically degrading high viscosity polyacrylamide(PAM) solution from EOR(enhanced oil recovery) process. The influences of solution pH, current density and electrolyte concentrations were investigated on the electrocatalytic PAM degradation. The results showed that the degradation performances of PAM using the composite electrodes were better than those of graphite electrode and nano-MnO₂ catalysis. The viscosity reduction of PAM solution were optimally achieved up to 90.2% using the composite electrodes within 2.0h under current density of 10mA/cm², pH=7.0, 0.3mol/L sodium sulfate solution. The novel multifunctional electrodes had encouraged suitable alternatives to apply electrocatalysis for reducing viscosity and recycling polyacrylamide wastewater with the water resource conservations in oil production technology.

The refining treatment of medium and low temperature coal tar was carried out by fraction cutting and mild hydrogenation. Mesocarbon microbeads were prepared from refined raw materials by staged thermal polymerization. The effects of refining treatment conditions on the properties of raw materials, macroscopic appearance and microcrystalline structure of mesocarbon microbeads were investigated. The raw materials were characterized by FTIR, GC-MS, group composition and elemental analysis, and the mesocarbon microbeads were characterized by SEM and XRD. The results showed that the distillate oil at 300—430℃ in medium and low temperature coal tar was better fraction for preparing mesocarbon microbeads. The content of n-heptane soluble (HS) and pyridine insoluble (PI) was 84.76% and 0.23%, respectively, while heteroatom was low and the ring number of aromatic compounds was 2—4. The refined raw materials were obtained by mild hydrogenation of 300—430℃ distillate oil under the conditions of T_H=350℃, p=8MPa, t=1.5h, the mass ratio of catalyst to distillate oil is 1∶40, and mesocarbon microbeads which were prepared from refined raw materials by thermal polymerization at 420℃ for 6h had better macroscopic appearance and microcrystalline structure. The particle size of mesocarbon microbeads ranges from 5μm to 15μm. The surface of the mesocarbon microbeads was smooth and the microstructure was globe-shaped. After calcination at 1450℃, the degree of graphitization reached 12.33%.

Polymer microspheres with inter-connecting pores are widely used as microsphere materials. In this paper, the solvent-evaporation method was used to prepare poly(methyl methacrylate) microspheres with the controllable structures and their inter-connecting properties was studied. It was found that the structure of polymer microspheres was a function of the polymer concentration and the dosage of porogen. By increasing the polymer concentration and decreasing the dosage of porogen, the structure of microspheres evolved from the hollow to the porous; and as the concentration of the polymer increased and the dosage of porogen decreased, the number of the internal pores increased and the pore diameter decreased; at the same time, the inter-connecting performance of the microspheres decreased. A better inter-connecting performance was observed when the microspheres were in hollow structures or with few big pores inside, compared with those ones with the compacted porous structures. In order to improve the inter-connecting properties of the porous polymer microspheres, a mixed organic solvent was used to instead of the single organic solvent and the results showed that the change on the porous structures of the microspheres was not obvious; however, the inter-connecting properties of the polymer microspheres increased. Microspheres were observed to have the best interconnecting property at R_TCM/DCM=3∶10, compared to single solvent conditions, at which the sedimentation rate of polymer microspheres in aqueous solution increased from 30% to 60%. The temperature incremental rate had a great influence on the microspheres’ inter-connecting properties. A slow or fast temperature incremental rate was adverse to the microspheres’ inter-connecting properties. The sedimentation rate of the prepared microspheres in water is the highest at 40℃/25min, which was about 60%.

In order to investigate the effects of straw type and ratio change on microbial community structure in sludge anaerobic digestion system, 16S rRNA high-throughput sequencing technology was used to analyze the microbial community in sludge-straw anaerobic co-digestion system. The results showed that addition of corn straw had a great influence on the pH and volatile fatty acids (VFAs) in the system, especially on acetic acid. Addition of wheat and rice straw had a greater effect on alkalinity, but the VFAs and acetic acid concentrations in the system increased when the ratio increased, especially 1∶1.5 (mass ratio of volatile solids). Through the analysis of microbial community structure, it was found that the change of straw ratio and types could significantly increase the relative abundance of hydrolysis bacteria and acidification bacteria (p＜0.001) in anaerobic systems, for instance, Bathyarchaeota, norank_p_Bathyarchaeota (archaea), Bacteroidetes, Cloacimonetes, Synergistetes, unclassified_p_ Cloacimonetes, norank_c_Bacteroidetes_vadinHA17, Christensenellaceae_R-7_group, norank_f_Porphyromonadaceae, unclassified_f_Ruminococcaceae, Bacteroides, Prolixibacter, Longilinea and Leptolinea (bacteria), but the growth of methanogens (Methanosaeta) and hydrogen methanogenic bacteria (Methanospirillum, Methanobacterium and Methanobrevibacter) could be inhibited. It was also found that the addition of straw significantly promoted the growth of methylotrophic methanogens (Methanomassiliicoccus) (p＜0.001), which affected the methanogenic properties of anaerobic systems.

E.coli K-12 MG1655 succinate dehydrogenase gene, sdhC (encoding membrane protein sdhC), a double-stranded DNA, was used as a scaffold to design a 17.68nm tetrahedron with DAEDALUS software. The sdhC DNA strand self-assembled into a nanocone polymer exactly as similar as the front design. The morphology, structure and chemical composition of the samples from several experiments were assayed by agarose gel electrophoresis, scanning electron microscope and transmission electron microscopy, at the same time, the three-dimensional structure was imaged by high-resolution atomic force microscope in liquid. The results showed 16 staple strands designed by DAEDALUS folded the 624 bp double-stranded DNA of sdhC gene into nanocones with an average length of 19.05nm, which is only 1.37nm difference with the prediction. This study provides a new method for constructing nucleic acid nanomaterial with common genetic sequences beside M13mp18 in DNA origami.

Polyamine inhibitors are drilling fluid additives containing amine groups in the molecular chain. Compared with shale inhibitors such as inorganic salts and monomolecular ammonium salts, their strong inhibition to shale formations has attracted much attention. However, the decomposition of polyamine molecules at high temperatures affects the inhibitory effect, while the depth of the working well increases, and the difficulty of development tends to make temperature a decisive factor in limiting the application of inhibitors. Therefore, the development of high temperature and high inhibition shale inhibitors is of great significance for drilling operations. The authors classify polyamine shale inhibitors with high temperature resistance into chain polyamines, hyper branched polyamines, and special functional groups according to the molecular chain form of the polymer. The properties and application status of these three types of high temperature shale inhibitors were reviewed. The future research of polyamine shale inhibition in improving the temperature resistance and inhibition was proposed to provide reference for related research.

In order to improve the poor performance of PBO composite bonding, a polar group hydroxyl group is introduced into the benzene ring for structural modification, and 3,3′-diamino-4,4′-dihydroxybiphenyl hydrochloride（DADHBP·2HCl） is a key monomer for modification. The intermediate 3,3′-dinitro-4,4′-dihydroxybiphenyl (DNDHBP) and the hydroxyl-modified PBO monomer DADHBP·2HCl were synthesized by the nitration and reduction reaction of 4,4′-dihydroxybiphenyl, and the reaction conditions were optimized. The results showed that for the nitration reaction, the yield of 65% of DNDHBP with a HPLC purity 98.65% could be achieved under the conditions of reaction temperature 5℃, reaction time 2.5h and n(DHBP)∶n(HNO₃)=1∶2 in the mixed solvent of toluene and glacial acetic acid. The catalytic reduction reaction was conducted in ethanol as solvent under the conditions of n(DNDHBP): n(N₂H₄·H₂O)=1∶5.5, reaction temperature 78℃ and reaction time 9h using ferrous sulfateheptahydrate as auxiliary [n(DNDHBP):n(FeSO₄·7H₂O)=1∶9]. After the hot filtration of the reaction mixture, DADHBP·2HCl could be obtained with a yield of 67.16% and a HPLC purity of 98.20% through refined by hydrochloric acid. The intermediate and product structures were confirmed by FT-IR, ¹H-NMR and EI-MS.

Styrene-maleic anhydride copolymer(SMA) was synthesized by solution polymerization, and then the salted styrene-maleate was used as a protective colloid to prepare perfume oil filled melamine formaldehyde microcapsules by in-situ polymerization. The effects of SMA sodium salts with different molecular weights on the dispersion of perfume oil and the preparation of perfume oil microcapsules were investigated. It was found that by decreasing the molecular weight of SMA, the particle size and the particle size distribution of perfume oil droplets decreased, while the dispersion stability of the perfume oil droplets increased. When the viscosity of the SMA sodium salt solution(10% mass fraction) was ≥145 mPa·s, the particle size of the prepared microcapsules was in the range of 5—20μm, with spherical shapes, smooth surfaces and the thickness of the shell is relatively uniform. When the viscosity of the SMA sodium salt solution (10% mass fraction) was ≤67mPa·s, only few microcapsules can be prepared. The performance of the imported SMA 520 was similar to the self-prepared SMA sodium salt solution (10% mass fraction) having a viscosity of 314mPa·s.

Microbiological nitrogen removal is an economical and effective method for nitrogen pollution control in water. Microbial nitrogen removal processes, at present, mainly contain anammox, nitrification, denitrification, simultaneous nitrification and denitrification and so on. Iron is a ubiquitous metallic element in environment and also one of the important trace elements for microorganisms. In microbiological nitrogen removal systems, the addition of iron salts or iron-containing solid compounds will have certain impacts on microorganisms and the nitrogen removal processes, and such impacts of iron differ for different microorganisms and nitrogen removal processes. Here, the effects of iron on the removal of nitrogen-containing pollutants by different nitrogen removal processes including anammox, nitrification, denitrification and simultaneous nitrification and denitrification, as well as the relationship between iron and enzyme activity, electron transfer, proliferation and enrichment of nitrogen removal microorganisms , and formation of biofilm, floc and granule in biological reactor for nitrogen removal, are comprehensively reviewed. This will help to comprehensively understand about the role of iron in microbial nitrogen removal systems and the mechanism involved, and provide a reference for the enhancement of microbial denitrification processes and improvement of microbial denitrification efficiency by the addition of iron.

Focused on the huge energy consumption by sodium-based CO₂ capture process of the post-combustion CO₂ capture technology, a cogeneration unit (CU) was integrated into the coal-fired power plant with the CO₂ capture process (CCPP), in which the returned water from the heat network could be used to recover the lower-grade waste heat. Two different configurations of this CCPP-CU system, namely the separated extraction configuration and the mixed extraction configuration, were proposed, and the thermal performance of these two configurations was analyzed. Results showed that the comprehensive energy consumption of the separated extraction configuration and the mixed extraction configuration could be reduced from 4.05GJ/t CO₂ to 1.26GJ/t CO₂ and 1.13GJ/t CO₂, respectively. Besides, the corresponding heat capacity of the CCPP-CU system was increased by 67.5% and 72.8%, which showed remarkable economic benefits. Effects of key parameters on the energy consumption of the mixed extraction configuration were investigated, which showed that the carbonation reaction temperature and the heat network return water temperature had great impact on the utilization ratio of the waste heat and the energy consumption of CO₂ capture system.

The alcohol-amine method is a mature CO₂ capture technology, which has the advantages of high absorption speed and good removal effect, but its operation cost is high and desorption energy consumption is large. Therefore, based on reducing regeneration energy consumption of CO₂ capture system in flue gas by amine method, the energy saving of conventional CO₂ capture system by amine method was studied in this paper. Based on the energy-saving research of conventional amine CO₂ process, the energy-saving technology of compressed heat pump was introduced, and the CO₂ capture process model based on compressed heat pump technology was established by Aspen Plus software. The coupling of compressed heat pump with MVR heat pump, split-flow desorption, distributed heat transfer and inter-stage cooling was studied. By simulation and optimization, the optimal energy-saving process combination was finally obtained as CO₂ capture process of “desorption tower compressed heat pump+lean-liquid MVR heat pump+split-flow desorption + inter-stage cooling” coupling. When the split-flow ratio of top gas of desorption tower was 1/3, the split-flow ratio of rich and cold liquid was 0.05. The inter-stage cooler was located on 17 trays of the absorption tower. When the input cooling capacity of the absorption tower was -3.0GJ/h, the regeneration energy consumption of the system was the lowest, which is 2.533GJ/t CO₂. Compared with the conventional organic amine process, the energy saving rate was 39.748%.

Biochar was prepared from corn straw at 450℃, and the biochar was applied to the heavy metal contaminated soil in mining area with 5% carbon/soil dry weight ratio. The effects of biochar addition on the pH of soil leachate, vertical migration behavior and cumulative release of heavy metals were analyzed by soil column leaching test in laboratory. The results showed that the pH of soil leaching solution in biochar added soil was significantly higher than that of the control treatment, indicating that adding biochar had advantages in alleviating soil acidity. Compared with the control, the addition of biochar reduced the risk of heavy metal migration to the lower layer. The vertical migration of Pb, Cu, Zn and Mn in the soil column after leaching decreased by 65.93%, 50.95%, 49.29% and 30.95%, respectively. The order of inhibition of vertical migration of heavy metals by biochar was Pb＞Cu＞Zn＞Mn, and biochar had the best passivation effect on Pb. With the increase of leaching solution volume, the leaching cumulative releases of Pb, Cu, Zn and Mn in soil appeared to be consisted of two phases involving the initial rapid process followed by a slow continuous process. The cumulative release of the four heavy metals was Pb＞Mn＞Zn＞Cu, and the cumulative release of heavy metals was significantly reduced by adding biochar. The release processes of heavy metals from soil were fitted with mathematical equations. The Elovich equation could better describe the release process of heavy metals, which indicated that the mechanism of leaching and releasing process of these four heavy metals in soil was not a single reaction process, but a complex reaction process with large change of activation energy. After adding biochar, the b value of all heavy metals was lower than that of the control group. The migration rate of heavy metals decreased with the addition of biochar, indicating that the adding biochar could improve the adsorption capacity of soil to heavy metal ions, reduce the migration of heavy metals caused by soil leaching, and could realize the remediation of the soil in heavy metal complex contaminated mining areas.

The treatment effect of acid mine drainage by sulfate-reducing bacteria fed with hydrogen as the sole electron donor was studied. In this paper, the pH and ORP, the target metabolites H₂S and ∑S^2-(HS^-, S^2-), the heavy metals and total organic carbon in effluent were analyzed. The research showed that the pH rose rapidly to 8.8 and the ORP declined to -415mV in the bioreactor. The activity of sulfate-reducing bacteria was better at the high \mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-} concentration, and the accumulation of target metabolites H₂S and ∑S^2- were 88mg/L, 172mg/L, respectively. The removal rates of Zn²⁺, Fe²⁺, Cu²⁺, Mn²⁺ were 94.3%, 94.7%, 97.5%, 81.7%,respectively,the effluent concentrations of heavy metals Cu²⁺, Zn²⁺ were 0.52mg/L, 1.99mg/L respectively, the pH of neutralization precipitation water was 6.9 and the effluent quality could reach the first level of integrated wastewater discharge standard. The effluent TOC≤3mg/L, which was lower than that with the organic carbon as the electron donor. The H₂ culture bioreactor was mainly dominated by Desulfovibrio.

The extraction-distillation hybrid process for the treatment of sulfolane waste water from polyarylether resin polymerization process was developed herein. Using NRTL activity coefficient model, Aspen plus was employed to simulate the hybrid process with dichloromethane as solvent. The sensitivity analysis tools were used to optimize the parameters of extraction column and distillation column. The simulation results indicated that when the number of equilibrium stages of extraction column was 7, solvent ratio was 1∶1, the number of theoretical stages of the distillation column was 5 and the feed entered at stage 3, the sulfolane concentration of the wastewater was reduced from 100g/L to 34mg/L, and the mass fraction of recovered sulfolane was 98.31% with the recovery of 99.95%. Therefore, water and sulfolane can be recycled after treatment. Compared with the four-effect evaporation process, the heat duty of the extraction-distillation hybrid process was reduced by 37%, which had a great potential for industrial application.

A kind of fixed bed ozone catalytic oxidation equipment with reflux was designed, and the properties of α-Fe₂O₃/γ-Al₂O₃ catalyst prepared by impregnation method was characterized, then the performance of ozone catalytic oxidation for the concentrated water of coal chemical reverse osmosis was studied by α-Fe₂O₃/γ-Al₂O₃ catalyst in the fixed bed equipment with reflux. The results showed that the specific surface area, average pore diameter, total pore volume and the active component α-Fe₂O₃ content of the α-Fe₂O₃/γ-Al₂O₃ were 161.74m²/g, 10nm, 0.4533cm³/g and 8.73%, respectively. With the increase of catalyst loading height, ozone concentration and hydrogen peroxide dosage, the COD removal rate of the reverse osmosis concentrated water increased firstly, and then decreased, the reflux could significantly increase the rate. The suitable values of the catalyst loading height in the equipment, ozone concentration, dosage of hydrogen peroxide and reflux ratio were 350mm, 300mg/L, 150mg/L and 50%, respectively, which the COD removal rate of ozone-catalyzed oxidation reverse osmosis concentrated water was as high as 74.33%. Most of the dissolved organic matter and humic acids in the reverse osmosis water from coal chemical industry had been decomposed after ozone catalytic oxidation.

Ash deposits on convection heating exchanger surfaces reduce their efficiency. Ash samples were collected from a circulating fluidized bed (CFB) municipal solid waste incinerator, which included loose-like fouling and ash deposits from the economizer and evaporating heating exchanger. The composition, microstructure, particle size distribution, surface analysis and the element analysis of those samples were studied with scanning electron microscope (SEM/EDX), X-ray fluorescence (XRF), and laser particle analyzer etc. Results indicated that economizer loose-like fouling contains a high proportion of small and irregularly shaped particles while there are some agglomeration particles among evaporating heating exchanger fouling. The particle size of most fouling of these two kinds is between 0—100μm. The ash fusion temperature of economizer fouling is 80℃ lower than that of evaporating heating exchanger. Besides, the main mineral phase contained in the ash deposits is CaSO₄. Compared to ash deposits formed on the economizer surface, evaporating heating exchanger deposits contain a relatively higher CaO and SO₃ but lower Al₂O₃ and SiO₂. The content of Ca and S from the inner layer of the ash is gradually reduced, while the content of Al and Si is gradually increased. The content of K, Na, Fe and Cl in the inner layer of the ash is higher than that of the other layers.

Copper-containing wastewater mainly comes from electroplating, non-ferrous smelting, non-ferrous metal mining, dye production and other processes. Due to its high toxicity and bioaccumulation, Cu(Ⅱ) is a serious threat to the ecological environment and human health. In this paper, concentrated red hydrochloric acid, ferric chloride (FeCl₃), hexadecyl trimethyl ammonium bromide (CTAB) were used to treat and modify Bayer red mud (RM), and a high removal rate was prepared. It was characterized by SEM, TEM, XRD, BET, elemental analysis, FTIR, thermogravimetric analysis, etc., and the effects of solution pH, adsorbent dosage and adsorption temperature on the adsorption of Cu(Ⅱ) in aqueous solution were investigated. The results showed that the specific surface area ratio of acid-immersed red mud (RM-HCl) was increased by 20 times. After modification by FeCl₃ and CTAB, the surface of red mud was combined with a large amount of hydroxyl oxidize iron (FeOOH) and improved the surface properties of the adsorbent as well as affinity and single layer adsorption capacity between adsorbent material and Cu(II). The adsorption time of copper by comprehensive modified red mud (FeCl₃/CTAB/RM) reached equilibrium at 100min, the optimum adsorption pH was 6, the optimal adsorbent dosage was 2g/L, and the saturated adsorption amount was 221mg/g. The adsorption process was in good agreement with the quasi-secondary kinetic model and the Langmuir adsorption isotherm model. The thermodynamic data indicated that the adsorption is an endothermic and spontaneous process. The adsorption mechanism is mainly the grafting of hydroxyl groups (Si-OH, α-FeOOH and β-FeOOH) on FeCl₃/CTAB/RM surface and doped chlorine atoms and surfactants. It effectively removed Cu(Ⅱ) by physical adsorption (chelation, electrostatic attraction) and chemical adsorption (ion exchange, hydrogen bonding).

In order to improve the efficiency of the actual dye wastewater treatment by the iron-carbon micro-electrolysis process, the response surface method was used to optimize the process conditions. A response surface model was constructed and the significance of the model was analyzed when removal efficiency of COD was used as response value and initial pH, iron dosage, iron-carbon mass ratio and reaction time were used as experimental factors. The results showed that when the initial pH was 3.53, the iron dosage was 83.92g/L, the iron-carbon mass ratio was 0.82 and the reaction time was 78.48min, the predicted COD removal efficiency was 75.25%. The deviation was 0.23% (＜2%) compared with the measured value. The model can be used to predict the change of COD removal efficiency. The biotoxicity of the influent and effluent in the iron-carbon microelectrolysis process was tested by E.coli. Compared with the influent group, the release of lactate dehydrogenase (LDH) in the effluent group decreased from 2.13 times to 1.64 times in the control group, while the production of reactive oxygen species (ROS) decreased from 19.26 times to 4.81 times in the control group. The cell death rate decreased from 98.1% to 61.5%, and the growth phase was extended from 5h to 9h, and the BOD₅/COD rose from 0.151 to 0.416. Therefore, the iron-carbon microelectrolysis process has the effect of reducing the biological toxicity of dye wastewater.

Sponge iron modified by low temperature plasma technology was used to activate persulfate (PS) for phenol wastewater treatment. The pre and post-modification materials were characterized by Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD) and scanning electron microscopy(SEM). Phenol was the target pollutant. The effects of catalyst dosage, catalyst/PS molar ratio, pH and initial concentration of phenol on plasma-modified sponge iron activated PS treatment of phenol-containing wastewater were investigated by static experiments. The results showed that the modified sponge iron had a larger specific surface area, pore volume and pore size, so the activation ability of PS was significantly improved. Under the optimal reaction conditions(the dosage of plasma-modified sponge iron is 0.4g/L, catalyst/PS molar ratio is 1∶15, the solution pH is 2 and the initial concentration of phenol is 250mg/L), the removal rate of phenol was 95%. The reaction process conformed to the second-order reaction kinetics, which mainly due to the oxidation of sulfate radicals and hydroxyl radicals. The persulfate activated by plasma modified sponge iron can effectively treat phenol wastewater, which provides some new solutions for phenol wastewater treatment.

To investigate the law of heavy metal migration and transformation during sludge pretreatment process, the sludge was treated with different amounts of Fenton reagents, and the chemical morphological changes of the heavy metals, including Zn, Cd, Mn and Ni, and the dissolution behavior in the subsequent bioleaching process were analyzed. The results showed that after Fenton treatment (Fe²⁺=1.00g/L, H₂O₂=9.00g/L), the capillary suction time decreased in a short time, but it had no significant effect on the final sludge dewatering after bioleaching. The proportion of the unstable states of heavy metals Zn, Cd and Mn increased from 37%, 84% and 79% to 90%, 93% and 84%, respectively. But there was no significant change in Ni. Furthermore, the contents of the four heavy metals Zn, Cd, Mn and Ni after bioleaching decreased from 3451.52mg/kg, 6.45mg/kg, 443.40mg/kg and 94.96mg/kg to 376.74mg/kg, 1.10mg/kg, 141.66mg/kg and 21.77mg/kg, respectively. Compared with the individual bioleaching treatment process, the residual content of these four heavy metals was decreased by 36.2%, 26.17%, 30.92% and 27.89%, respectively. The relative dissolution rates of the heavy metals in the bioleaching process were described by the kinetic equation, and the order was Mn＜Cd＜Zn＜Ni.