Chemical unit operation for separation and phase equilibria are inextricably linked, and the phase equilibrium phenomenon has drawn great attentions of chemical engineers and researchers. With the rapid development of computing technology and statistical mechanics, the study of phase equilibria using molecular simulation method has been a hot topic in recent years. In this paper, the research progress in this filed over the past two decades was summarized, and the molecular simulation methods of phase equilibria and the development of force fields were discussed in detail. The applications of phase equilibria by molecular simulation to calculate the macroscopic thermodynamic data, to select the extractant and to analyze the thermodynamic mechanism were introduced systematically. The analysis showed that the molecular simulation method was well developed for the calculation of macroscopic thermodynamics data and the phase equilibrium data of various systems can be accurately calculated. The advantage of the molecular simulation method in the selection of the extractant was elucidated. Meanwhile, the lack of research in the microscopic analysis of thermodynamic mechanism was pointed out. Moreover,the development of molecular simulation method in the field of phase equilibria was analyzed and forecasted.

In the field of multiphase flow,the research on heavy oil-water flow has become the focus but it is still in its infancy. The advances in study on heavy oil-water flow at home and abroad were introduced and analyzed from three aspects in this paper,that is,phase inversion,flow pattern transition and pressure drop. In the aspect of phase inversion,the mechanism and influence factors of heavy oil-water flow were described by experts at home and abroad. In terms of flow pattern transition,the factors affecting the transition of stratified flow and dispersed flow were introduced. In the aspect of pressure drop,the factors that affected the pressure drop of stratified flow,dispersed flow and annular flow were analyzed.In addition,the present calculation model and the accuracy of pressure drop prediction were discussed. Furthermore,the paper also focused on the problems in the research of heavy oil-water flow and pointed out two important developments in the future. First,the relevant parameters needed to be revised when the experimental results were applied to the actual pipeline. Second,the influence of the curved pipe on the flow pattern transition and phase inversion of heavy oil-water flow needs to be further studied,which was of great significance to the safety and economic operation of pipeline.

The transesterification of dimethyl carbonate(DMC)and phenol to diphenyl carbonate(DPC)is considered as a clean production route,and this route is usually carried out through two steps. However,in the second step the disproportionation of methyl phenyl carbonate(MPC)usually cannot react thoroughly,which,to a certain degree,have deeply limited the production of the target product DPC. Therefore,the disproportionation of MPC is a key step to synthesize DPC in the transesterification reaction from DMC and phenol and further research of it is of great significance. The reaction thermodynamic,dynamics,catalysts and the synthesis process of the disproportionation of MPC are mainly reviewed. Problems on dynamics and equilibrium constraint of the disproportionation are discussed in details. The proper way to break the equilibrium constraint is to reduce the distillation pressure in the disproportionation and the high selectivity of DPC relies on the property of the catalyst. The main research of the catalyst are supposed to be directed to heterogeneous catalyst. Finally,the perspective and evaluation of domestic researches are given.

The development of modern industry has posed new demand for safer chemical processes,which has also created new opportunities for micro chemical engineering technology considering its unique advantages in promoting reaction safety. Starting from the characteristics of fluids inside the microchannel,in this review we have explained the change on transfer efficiency and fluid behavior due to the miniaturization in dimension. With literature reports and application cases chosen carefully,we have summarized the function of microreactors in improving the inherent safety of chemical processes in three aspects-rapid heat removal and uniform concentration distribution due to intensified heat and mass transfer,reduced exposure risk and explosion risk attributed to the confinement of hazardous material,and guaranteed safety of reactions under extreme conditions. In the concluding remarks,comments on challenges to microreactors such as high production cost,mal-distribution in parallel unit and demand for new catalyst loading method have been provided,as well as prospective overview of its future application.

The working principle and properties characterization of two closed thermosyphon were introduced in this paper. The research on the closed thermosyphon heat transfer enhancement was summarized from aspects of inherent parameters and operating conditions. The main mechanism of influence on performance of the closed thermosyphon by changing parameters was introduced,such as type of working fluid,filling ratio,structural parameters,surface treatment, heating power, operating temperature, inclination angle and,cooling medium flow rate. Research status and influence of variation of the above factors on heat transfer performance of closed thermosyphon were summarized. Shortcomings and limitations of the present study on heat transfer enhancement of closed thermosyphon were also pointed out. Suggestions were put forward for further researches,for example,the synergy between various factors should be determined,influence of other factors should be eliminated,scope of variables should be expanded in researches. In addition,it was suggested that study on enhancement of heat transfer in closed thermosyphon and strengthening mechanism of heat transfer and mass transfer in the closed space,such as boiling and condensation,should be combined. Heat and mass transfer theory and calculation formula should be improved.

Reactive dividing wall distillation is one of the chemical process intensification technology,which has recently drawn much attention. It combines the advantages of reactive distillation and dividing wall column,which can reach the state of low energy consumption,less space occupation,investment saving,high conversion rate and good selectivity. Also it is a highly integrated and coupled technology of reaction and separation. Based on the review of the development of reaction distillation and dividing wall column,the new progresses and applications on reactive dividing wall technology in recent years were introduced from experiment and simulation,column internals and the design of control strategy. The main obstacles in the process of the industrialization and the existing problems were pointed out. Then the paper summarized that the research of the multicomponent system and the optimize design of the control structure possibly would be the development direction. Finally,the wide development prospects in the field of preparation of biodiesel,ethers and other renewable energy sources as well as oil refining and liquefied petroleum gas are indicated.

1,4-butanediol(BDO),hydrogenation product of 1,4-butynediol(BYD),is an important organic chemical raw material. The main problems of industrial hydrogenation of BYD are high pressure,huge capital investment and catalyst deactivation. Characteristics of the hydrogenation process of BYD,characteristics and confronting problems of hydrogenation process,development of Ni-based,Pt-based and Pd-based catalysts for hydrogenation process and new types of reactors were reviewed. Based on the characteristics of great impact of hydrogen concentration of catalyst surface on the BYD hydrogenation reaction process,it was proposed to improve the hydrogenation process of BYD by enhancing the gas-liquid,liquid-solid mass transfer efficiency and to reduce the hydrogenation pressure. The activity and stability of the catalyst could be improved by adding supporting metals and change of the carriers. The development trends of low pressure 1,4-butynediol hydrogenation catalyst and reactor were discussed. Combining the magnetic properties of the Ni-based catalyst used in the hydrogenation process,the potential application of magnetically assisted fluidized bed reactor in BYD hydrogenation process was proposed.

Boiling is widely used in industries,such as the large scale integrated circuit cooling,CPU cooling,energy storage and so on. Porous metal is rapidly becoming a new hot spot in the field of boiling enhancement because of its high specific surface area,excellent thermal conductivity as well as a dense potential bubble nucleate sites. Coupled with wettability modification,porous surfaces can greatly improve the critical heat flux(CHF),easily control the boiling from disorderly to orderly. This review focused on the effects of porous surface and wettability on boiling heat transfer performance and heat transfer mechanism,which involves in porous sizes,shapes,nucleation site distribution and wettability. This paper also discussed the model evolution of boiling heat transfer; the Kandlikar series CHF model based on the Zuber formula was analyzed. Microlayer evaporation and transient conduction are considered as the main mechanism to enhance nucleate boiling. Micro/nano porous with local wettability can improve boiling heat transfer,which could be a potential new research idea.

As an important protective layer of petroleum refinery installations,gas detectors can greatly improve the detection efficiency and reduce the loss if they are placed in a reasonable position. From the perspective of minimizing leakage risks,a quantitative optimization method of gas detectors placement was proposed. Several external factors of leakage diffusion process were quantified to calculate the scenarios occurrence probability,leakage consequence and risks. According to the failure mode and redundancy structure,a minimal risk p-median problems(MRPMP-UVCVaR)optimization model was demonstrated,as well as unavailability,voting effects and Conditional-Value-at-Risk(CVaR) was considered. Particle swarm optimization(PSO)was used to solve the model. The applicability of the methodology was shown in a case study and the results were compared with the original scheme,improving the design of detection systems on a risk-oriented basis. Future work including the research of the experimental validation and multi-objective optimization will be taken to improve the practicability of the optimization model.

Thermo-physical properties of aqueous solutions of potassium perfluorooctanoate(PFOK),with mass fractions of 0.02%,0.05%,0.1%,0.2%,0.5%,were tested respectively. It was found that significant changes in a little amount of PFOK could lead to surface tension of water,viscosity followed,while the specific heat,density,thermal conductivity and other parameters of water were less affected. An experimental study on characteristics of the pulsating heat pipe(PHP),with the inner diameter of 2.5mm of copper pipe,using water of different surface tensions and viscosities was carried out. The results showed that promotion of heating power on startup time is obvious if the heating power input is no more than 60W. Change laws of startup time and thermal resistance with the effect of surface tension present "W" type image due to the increment of viscosity. Besides,the effect of surface tension and viscosity on the thermal resistance is decreased with the increase of the heating power.

Large inclination upward pipe is common in hilly terrain area. In this paper, flow patterns were obtained and gas-liquid two-phase flow pressure fluctuations in the upward pipe were measured using an indoor experiment apparatus. Six flow patterns were observed during the experiment. Both time domain,PDF(probability distribution function),CDF(cumulative distribution function)and PSD(power spectral density)characteristic values of the pressure fluctuation under different superficial gas velocity as well as superficial liquid velocity and angle were obtained. Results showed that,due to the expansion of the gas and the inertia of the slug in the large inclination,the pressure value of the pressure sensing point would be lower than the higher point during the blowout of severe slugging. The characteristics of time domain,PDF,CDF and PSD characteristic values of the pressure fluctuation under different superficial gas velocity,superficial liquid velocity and angle were compared and analyzed,which can be used to identify flow patterns and provide reference for selection of equipment and the security operation of pipelines. Distributions of PDF showed single-peak and dual-peak. The slope,knee,and distribution of CDF were different for different flow patterns. Distributions of PSD showed single-peak,dual-peak,triple-peak,multi-peak and no-peak. The period and the value of pressure fluctuation of severe slugging increase with the angle augmented.

In process industry,many existing heat exchanger networks have huge energy recovery potential due to the unreasonable network structure. Therefore,it is necessary to retrofit those heat exchanger networks. This paper combined the exchanger reassignment strategy with the stage-wise superstructure. The exchanger reassignment strategy was improved further to make full use of existing heat exchangers. Meanwhile,more economic option was chosen by comparing the additional heat transfer area cost and the new heat exchanger cost when an existing heat exchanger was reused,ensuring a lower investment cost under the same energy-saving. A MINLP (mixed integer nonlinear programming) model to retrofit the heat exchanger network was built based on the stage-wise superstructure. The model considered the tradeoff among the additional heat transfer area cost,the new heat exchanger cost and the utility saving by retrofit. The retrofit of heat exchanger network was solved by genetic algorithm(GA). In a case study,the utility cost was reduced more than 60% and the retrofit profit would be 1.49×10⁷$/a. The total annual cost of the retrofit network was 1.290×10⁷$/a,which was 31.2% and 9.2% lower than the literatures,respectively. The utility cost was 42.4% and 17.0% lower than the literatures. A better retrofit result was achieved by the method proposed in this work.

In order to investigate hydrate plugging processes and mechanisms,a high pressure flow loop was newly designed and constructed where hydrate plugging experiments were performed in natural gas + diesel oil + water systems for a range of water cuts(30%-100%)and initial liquid flow rates(1600-2400kg/h). Based on the experimental data of hydrate morphology and flow parameters,hydrate formation and distribution characteristics in the flow loop were analyzed and two hydrate plugging types together with the corresponding hydrate plugging mechanisms were proposed. For hydrate plugging type Ⅰ,the plugging process can be divided into four stages. Formation and growing of a hydrate deposition layer is the governing plugging mechanism. For hydrate plugging type Ⅱ,it can also be divided into four stages. Liquid stratification and the sharp increase in viscosity is the governing plugging mechanism. In addition,silt-like hydrates and flocculent-like hydrate deposition layer were observed in hydrate plugging typeⅠwhile slurry-like hydrates with no obvious deposition layer were observed in hydrate plugging typeⅡ.

In order to improve the comprehensive performance of tube,heat transfer and resistance characteristics of a new type of sinusoidal tube were studied by numerical simulation using water as working fluid. The simulation indicated that secondary flow is caused by the periodic structure of the sinusoidal tube,which in turn strengthens fluid mixing,and reduces thermal boundary layer. As a result,heat transfer resistance is reduced and heat transfer enhanced. The measured data were compared with the simulation ones. Total heat transfer coefficient of the sinusoidal tube increased to 24.7%-58.4% than that of the straight tube, with the Re from 5000 to 28000. Under the same conditions,pressure drop in the sinusoidal tube was slightly larger than the straight tube. The difference between the two was 22%-38%. At the same time,resistance coefficient of the two tubes decreases as Re increases while the sinusoidal tube decreases more rapidly. When the Re number is larger than 13000,the resistance coefficient increment of sinusoidal tube is less than 20%. Considering the total heat transfer coefficient and pressure drop,heat transfer performance of the sinusoidal tube is better.

The reaction of using carbide slag and magnesium chloride as raw material to precipitate magnesium hydroxide in normal temperature was studied. The result showed that the impurity of carbide slag suppressed the secondary nucleation,resulting in the growth of magnesium hydroxide and bigger particle size. The nucleation of magnesium hydroxide was heterogeneous which was easy to take place due to the free energy of nucleation. The growth kinetics was modeled,and the results showed when the concentration of Mg²⁺ was higher than that of Ca²⁺,the growth rate was of no relevance to the concentration,while when the concentration of Mg²⁺ was lower than that of Ca²⁺,the growth rate increased with the increase of the concentration of Ca²⁺,indicating that the increase of the concentration of CaCl₂ could promote the growth of magnesium hydroxide.

A numerical calculation was attempted based on a high-pressure 1.5-stage steam turbine with rotor labyrinth seal. The variation of leakage vortex system in shroud exit cavity and the effect of main flow mixing with leakage flow on the aerodynamic characteristics of downstream stator were analyzed. Besides,the related losses generated by leakage flow were calculated. Results showed that there were large differences between main flow and leakage flow in the circumferential velocity and radial velocity. Main flow was deflected at the rotor blade exit when it mixed with the leakage flow,which led to the negative angles of incidence on the subsequent stator and the decrease of the stage efficiency. The mixing loss was the main part among the related losses generated by leakage flow. The tip clearance directly affected the size of backflow vortex which was closely related to the kinetic energy dissipation of leakage flow. Therefore,during the structure design process of the blade tip seal,it is necessary to reduce the tip clearance,enhance the disturbance of leakage flow in seal cavity,and decrease the velocity difference between leakage flow and main flow to improve the economy of steam turbine.

The current R22 alternative refrigerants are mainly R410A,R417B,etc.Their ODP is 0,but their GWP is relatively high,which is a transitional alternative.This study presents an investigation of the properties of low GWP ternary mixed refrigerant R1234ze(E)/R134a/R32(abbreviation NC01). The mixing mass ratio was 17%/33%/50% according to the REFPROP9.0. This software was used to analyze the environmental,thermal and circulatory properties of NC01. The ODP of NC01 is 0,GWP is 755,which is 57 percent lower than R22. Performance parameters such as critical temperature,critical pressure,saturation pressure and COP are similar to R22,and the volumetric heating capacity is higher than R22. An experimental study is performed in the water source heat pump unit.The resultsare compared with R22. Results showed that when the cold inlet water is 12℃ to 23℃,the new mixed medium's exhaust gas temperature is 2℃ to 3.6℃ higher than that of R22,corresponding pressure ratio is high 8.6%-14.8% than R22,heating capacity is 5%-11% higher than that of R22,the COP is about 4.5% lower than the average R22,the heating rate increased by 9% than that of R22. When the cold water inlet temperature is higher than 23℃,COP value is higher than R22. Finally,the results of the experiment are compared with the theoretical calculation,and the two fit well. This study provide reference for the research of the similar mixture replacing R22.

The shortage of fossil energy and the impact of CO₂ emission constitute a major challenge of 21st century,which makes a major incentive to get alternative power source of vehicle propulsion. Power cell,as the limiting factor of driving distance and safety issue of electric vehicles,plays a pivotal role in the upcoming ubiquitous usage of electric transportation. In this review,the improvements of power batteries in design and manufacture along with developments of electric vehicles was presented with an emphasize in introducing both the most promising cathode,anode and electrolyte materials in next generation of lithium-ion batteries and the status of new systems beyond lithium-ion batteries. Moreover,the possible areas of new power cell research were proposed:in the near term,enhancing the stability of Ni-rich cathode material and improving the conductivity of lithium-ion in solid-state electrolyte while reducing the volume effects of silicon anode material are good ways to ensure higher driving distance and better safety; in the medium term,magnesium-ion battery still has many side effects,however,multiple lithium-ion battery has already possessed higher energy than Ni-rich cathode material at low rates,which is worthy of more attention; in the long term,metal-air battery is in the starting point,while Li-S battery has good application future if shuttle effects caused by sulfur polycrystalline are reduced.

Affected by the oil import dependency,the price of the import natural gas and cost competition of chemicals,a preliminary industrialization development of the modern coal-chemical industry has been formed in China. As one of the paths of diversification of raw materials in the petrochemical industry,it will accelerate the transformation and upgrade in coal and other industries. With the rapid development of modern coal-chemical industry,some enormous constraints and challenges,such as its weakness in the condition of low oil prices,environment restriction and conflict in water consumption,are presented. Based on fully summarizing and analyzing the achievements of modern coal-chemical industry,this paper studied the problems confronted in the industry development,such as competitiveness under low oil price,environmental protection,carbon emission and water resource,and also put forwards solutions to resolve them. Finally,it analyzed the development of modern coal-chemical industry during the 13th Five-Year Plan,and made the outlook on the new development mode of coal-chemical industry,and gave some suggestment in the development of the way,competitiveness,industrial layout,scientific and technological innovation,standards and policies.

Levulinate esters is a kind of high value-added chemicals that could become a new generation of biofuels or fuel additives through alcoholysis for the utilization of cellulose resource. This paper reviewed the recent research progress of the preparation of levulinate esters through alcoholysis of cellulose under the conditions of acid catalysts systematically,and focused on introducing the catalytic effect of several kinds of catalysts researched in the filed such as inorganic acids,solid acids,mixed acids,and ionic liquids. The advantages and disadvantages of these catalysts were summarized. The mechanism of alcoholysis was discussed as well as the different catalytic role of Lewis and Br&248;nsted acids in the process of cleavage of glycosidic bond,isomerization from glucose unit into fructose unit,and further conversion of fructose unit into levulinate. The existing problems in the research of alcoholysis,such as harsh reaction conditions,low selectivity,unclear reaction mechanism were discussed. The future research directions of studying the details of cellulose alcoholysis mechanism and designing and synthetizing catalysts with higher activity and selectivity were pointed out.

The purpose of the study was to research the effects of various extractants on the solubility and the selectivity of aromatics from coal-derived naphtha. Using liquid-liquid extraction technology,the composite extractants were obtained for removing aromatics of the low aromatic naphtha. Firstly,considering the selective coefficient(S) and the partition coefficient(K) of C₆,C₇,C₈ aromatics in the coal-derived naphtha system with the five extractants,the main extractant dimethyl suifoxide(DMSO)was optimized. Secendly,the LLE data of the composite extractants and the low aromatic simulate oil prepared by the methyl cyclohexane and toluene systems were measured based on the main extractant DMSO supplemented with DMF,sulfolane,NFM or TEG. The experimental data were correlated by the hand correlation,and the auxiliary extractant DMF was proved to be more appropriate. Finally,the aromatic removal rate and the yield of solvent oil were served as indexes. The study explored the effects of composite extractant DMSO+DMF on removal of aromatics from coal-derived naphtha. The results showed that after five stages counter-current extraction under the optimized process conditions,the composite extractant DMSO+10%DMF had good effects on the removal of aromatics from coal-derived naphtha. The distribution coefficient of the aromatics from coal-derived naphtha was up to 0.215 and the maximum selectivity coefficient was 9.96. The total aromatic content decreased from 12.36% to 1.30%,reaching the standard of aromatic content in 120 solvent oil.

Hot gas filtration with raw syngas was continuously tested for 100 hours on a pilot scale purification system,the influence of biomass type,after-burning and back blow on pressure drops and temperatures of dust filter were studied,and the concentrations of gas component,tar and dust in the raw syngas and purified syngas were analyzed. It was found that compared with filtration with syngas from wood chip gasification,the pressure drop of the filter increased by 1200-1500Pa while filtration with syngas from co-gasification of pellet(25%mass)and wood chip(75%)the optimal temperature of filter was 450-550℃;after-burning with air was a more effective way to decrease the filter pressure drop than back blowing with N₂. The optimal flow rate of after-burning air was 10-12m³/h when the flow of syngas was 260-400m³/h;and the filter pressure drop remained at around 1200Pa. It was concluded that the pilot filtration system could continuously and stably run for 100 hours. The dust content in purified syngas was as low as 10-40mg/m³. The dust and tar removal efficiency was 92.3% to 99.8% and 31.0% to 92.5%,respectively. The filtration did not reduce the concentration of combustiblegases in purified syngas significantly.

Lignin is the most abundant natural aromatic polymer on earth. It is also a major byproduct of pulp and papermaking industry and lignocellulose biorefinery. Pyrolysis is one of the most promising ways to utilize lignin for production of fuels and chemicals. However,the pyrolysis characteristics of lignin products are greatly dependent on the isolation methods. In present work,five lignin products were isolated from sugarcane bagasse by organic acid,alkaline,and oxidative pretreatments,respectively,namely acetic acid lignin(AAL),acetosolve lignin(AsL),milox lignin (ML),peracetic acid lignin(PAAL)and alkaline lignin(AL). The pyrolysis of these isolated lignins was investigated using differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA). As indicated by TGA,all of the lignin products showed four stages of weight losses,namely water removal,glass transition,pyrolysis to small molecules and slow coking. The pyrolysis kinetics was analyzed by Coats-Redfern method. The results indicated that the pyrolysis process could be described as a second-order reaction in temperature range of 200-700℃ for PAAL,and 200-700℃ for the other four lignins. The activation energies were determined as 33.33kJ/mol,36.36kJ/mol,31.10kJ/mol, 24.74kJ/mol and 36.93kJ/mol for AAL,AsL,ML,PAAL and AL,respectively.

The permeability of the porous media in the presence of hydrate is one of the key parameters that affect the production potential of natural gas from hydrate reservoirs.The permeability of porous media depends on the percentage of porosity occupied by hydrate.It is of great significance to study the effect of hydrate saturation on permeability.In this study, a gas tank was used to precisely control the amount of injected methane gas to the core sample,and the permeability to water was measured by varying the methane hydrate saturation (0~35%)in porous media made of quartz sand,with an average particle size of 333.21μm.It was found that the permeability gradually decreased with an increasing hydrate saturation,which was consistent with previous studies.For hydrate saturation less than 10%,the solid hydrate had significant effect on blocking the pore space of the porous media,and the permeability tended to drop sharply.However,for the hydrate saturation more than 10%,the rate of permeability gradually decreased.Comparing the experimental results with those predicted by the empirical permeability correlation with the Masuda permeability model[K=K₀(1-S_H)^N),where N is integer],it was found that a value of N=13 fitted the experimental data better.

Supercritical carbon dioxide(scCO₂) has been widely used as an environmentally friendly solvent to replace the conventional organic solvent in green chemical processes. Among those applications reported,the synthesis of cyclic carbonates from epoxides in supercritical CO₂ has received a great interest. This review covered the recent progress in the synthesis of cyclic carbonates under supercritical carbon dioxide,with an emphasis on the state of the art of different kinds of catalysts employed in this reaction,including metal complex,quaternary onium salts,binary catalytic systems,ionic liquids,metal oxide,organocatalysts,et al. Furthermore,the advantages of supercritical carbon dioxide both as solvent and as reactant for this transformation were highlighted. From the economic and environmental point of view,organic catalysts,such as ionic liquids and quaternary onium salts,show promising potential application in the future development of chemical industry. It was also pointed out that the design and preparation of efficient and green catalysts are critical to this research field.

Catalytic combustion is one of the most effective technologies to remove volatile organic compounds(VOCs),and the key is the preparation of high efficient and stable catalysts. Three-dimensional ordered macroporous(3DOM) perovskite catalysts have attracted much attention owing to their excellent stability and activity in catalytic combustion of VOCs. This review analyzed the 3DOM perovskite-type catalysts for catalytic combustion in recent years. Firstly,the structure,properties and preparation methods of 3DOM perovskite-type catalysts were discussed. Then,the recent advances in their thermal stability,mechanical stability,hydrophobicity,oxidation reduction and acid and alkali were reviewed. Moreover,the problems to be solved were presented. Finally,it was also pointed out that future research should focus on the improvement of synthesis of colloidal crystal template,the preparation of multi-functional 3DOM perovskite catalyst and the influence mechanism responsible for the catalytic activity.

Mo/Mn-TiO₂ oxides catalysts have been prepared by impregnation method and employed to selective catalytic reduction of NO with ammonia(NH₃-SCR)on a laboratory fixed-bed. Experimental results of NO removal showed that,in the temperature range of 160-440℃,the dopping of Mn alone can significantly improved the catalytic activity of denitrification,and the NO conversion efficiency was more than 90% between 160-280℃,which shifted the active temperature window to the low temperature observably. With the further doping of Mo,there were different degrees of drop on the NO conversion rate in the temperature of 120-200℃,but the NO conversion rate can be further improved at 240-440℃;The de-NO_x activity decreased with the increase of SO₂ concentration on Mn-TiO₂ catalyst,and the SO₂ resistance dropped more sharply at lower reaction temperature. However,the resistance to SO₂ poisoning was greatly improved after the addition of Mo,and the efficiency of de-NO_x is still more than 90% at 240℃ when the SO₂ concentration was below 0.05%. BET,EDX,H₂-TPR,XRD and XPS were used to characterize the pore structure,surface elements distribution,reaction activity and the morphology of the catalyst systematically,and the mechanism of de-NO_x and SO₂ resistance of Mo/Mn-TiO₂ catalyst was clarified.

Due to the recycling difficulty and low activity of the catalyst during the preparation of styrene oxide,a new catalyst of gold nanoparticles stabilized by polymeric ionic liquid with thermoregulated biphasic function was synthesized,which has favorable properties of ‘mono-phase under high temperature, bi-phase under low temperature’,good stability and efficient catalytic ability. The results of catalyzing epoxidation of styrene showed that the catalyst has rather high catalytic activity with small loss and is easy to recycle. The conversion of styrene was up to 97.8%, while the selectivity of styrene oxide was 81.9%.

Cu-ZnO-ZrO₂(molar ratio CuO:ZnO:ZrO₂=5:4:1) catalysts were prepared using different precipitants(NH₃·H₂O、NaHCO₃、Na₂CO₃)by concurrent-flow co-precipitation method. XRD,XPS,H₂-TPR and CO₂-TPD were used to characterize the physico-chemical properties of the catalysts,and the catalysts activity were evaluated in a high temperature and high pressure micro-reactor. The influences of different precipitants on the catalyst precursors and catalysts component structure,CuO-ZnO interaction for methanol synthesis through carbon dioxide hydrogenation were studied. Results show that the influence of different precipitants on the physico-chemical properties and activity of catalysts was very great. When the precipitants of NaHCO₃ and Na₂CO₃ were used,they was helpful to produce aurichalcites in catalyst precursors,which,after calcination,were effective to prevent the growth of CuO particles,and to improve the dispersion of the metal copper oxide,increase the metal surface basic sites,enhance CuO-ZnO interaction,and raise the catalysts activity. More aurichalcites were produced in the catalyst precursors by using NaHCO₃ as the precipitant,and the particle size of the CuO was 8.6nm,the copper specific surface area was 15.38m²/g,the dispersion degree of copper was 11.9%,the selectivity of methanol was 42.29%,the yield of methanol was 0.094g/(g_cat·h),and the catalyst activity was the highest.

The catalysts of Ru-Zn(5%NaOH),Ru-Zn(H₂O),Ru-Zn(0.035mol/L ZnSO₄) and Ru-Zn(0.145mol/L ZnSO₄) were prepared by H₂ reduction in 5% NaOH,distilled water,0.035mol/L ZnSO₄ and 0.145mol/L ZnSO₄ using a co-precipitation method. The activities of the catalysts for selective hydrogenation of benzene to cyclohexene were in the order of:Ru-Zn(5%NaOH) > Ru-Zn(H₂O) > Ru-Zn(0.035mol/L ZnSO₄)≈Ru-Zn(0.145mol/L ZnSO₄),but their selectivities to cyclohexene were in the inverse order. The reason is that the reduction media could influence the composition and texture properties of the Ru-Zn catalysts,and further affects their catalytic performance. The Ru-Zn(H₂O) catalyst gave the highest cyclohexene yield among these catalysts,suggesting that the distilled water was the best reduction medium. The specific surface of Ru-Zn(H₂O) catalysts decreased with the increase of the reduction temperature,and the activity of the catalysts was lowered. Meanwhile,the particle sizes of the Ru-Zn catalysts increased resulting in the decrease of numbers of the corner sites and the edge sites on the catalysts suitable for hydrogenation of cyclohexene to cyclohexane. Thus the selectivity to cyclohexene increased with the increase of the reduction temperature. The Ru-Zn(H₂O) catalyst reduced at 100℃ gave a cyclohexene yield of 58.1%.

Magnetic polymer microspheres are composed of magnetic particles and polymer. They have received considerable attentions due to their particular structure and superior properties,and have obtained extensive applications in the medicine carrier,biological engineering,industrial catalysis and many other fields. In this paper,the structure types and preparation methods of magnetic polymer microspheres are summarized,of which the advantages and disadvantages are also discussed. And their applications,such as biological medicine,industrial catalysis as well as electromagnetic wave absorption and shielding,and the latest progresses in recent years have been reviewed. Furthermore,the current problems and future development prospects of the magnetic polymer microspheres in biomedical research have been also summarized and outlooked,including:① developing advanced preparation methods;② improving its biocompatibility and specificity to the patient cells through the surface modification of magnetic particles and design of polymer groups;③ achieving high magnetic targeting property,high drug utilization and controllable slow-releasing potential of drugs in the target area by studying on interface interaction and mechanism between drug and carrier;④ studying the change of drug carrier in the process of conveying and the influence of human environment on the drug delivery as well as the action mechanism of the patient cells.

Asymmetric supercapacitors(ASCs)have become a research hotspot in recent years owing to their outstanding electrochemical performances. Graphene,a novel two-dimensional carbon material,has many advantages such as large specific surface area,high conductivity,good mechanical property and excellent chemical stability,and thus is considered as an ideal carrier material for composite electrodes in asymmetric supercapacitors. In this paper,the status and perspective of graphene-based composite electrodes for asymmetric supercapacitors are reviewed. It is believed that the preparation of graphene with larger surface area and better electrical conductivity will be helpful to promote the application and development of graphene-based composite electrodes and to improve the performance of graphene-based supercapacitors. Finally,the trend of graphene-based composite electrodes in asymmetric supercapacitors is also briefly highlighted.

Activated carbon nanofibers with large surface area,high electrical and thermal conductivity and high porosity have gained extensive attention and how to further increase their surface area,porosity,especially micropore and mesopore content has been a hot issue to date. Electrospinning has been proved to be a versatile and effective way to prepare continual nanofibers. Activated carbon nanofibers prepared via as-spun precursor and followed by pre-oxidation,carbonization and activation are summarized. The effect of carbon precursor and pore structure control on the structure and properties of the activated carbon nanofibers are detailed discussed. The microstructure of activated carbon nanofibers were determined by as-spun precursor. The pore structure control,including interstitial pore,macrospore,mesopore and micropore is also introduced in detail. The application of activated carbon nanofibers in super capacitors electrode,electrochemical capacitive deionization,adsorption filtration and catalyst supports are reviewed. It may be expected that catalyst in situ loading on activated carbon nanofibers to increase catalytic active sites would be focused on in the future.

In this paper the different methods,such as ambient solid-state method and homogeneous precipitation method,were used to prepare the precursor of zinc oxide sorbent. The effects of reaction temperature and oxygen concentration on the in-situ regeneration of zinc oxide sorbent were investigated on the thermal balance device. Shrinking core model was employed to describe the kinetics of in-situ regeneration process of the precursor. The result showed that when the regeneration conversion rate was less than 80%,the regeneration reaction was mainly controlled by surface chemical reaction. When the regeneration conversion rate was higher than 85%,the regeneration reaction was mainly controlled by intra-particle diffusion. According to Arrhenius equation,the pre-exponential factors and activation energies of chemical reaction of the apparent reaction rate constant were 4.45m/s,43.12kJ/mol for ambient solid-state method and 1.01m/s,65.76kJ/mol for homogeneous precipitation method,respectively. The effective diffusivity factor and apparent activation energy of internal diffusion of the ambient solid-state method were 5.42×10^-2m²/s and 38.38kJ/mol,and those of homogeneous precipitation method were 1.29×10^-3m²/s and 43.29kJ/mol,respectively.

The metal compound oxide Mg_1.5Ti_1.25O₄ with a spinel-type structure was synthesized by the method of solid state reaction crystallization at fixed temperature. This spinel had versatile characteristics in respect of its chemical composition and stoichiometric number. It could be inserted or extracted some substitutable ions through changing stoichiometric number while keeping its own structure. Spinel-type metal compound oxide had advantages of better thermal stability, strong radiation resistance, simple preparation and good selectivity. The properties of Mg_1.5Ti_0.25O₄ such as XRD, Li⁺ extraction value, saturation capacity of exchange and distribution coefficient have been determined. The experimental results showed that this compound oxide had a stable structure. It could be inserted or extracted Li⁺ and has good Li⁺ selectivity and ion memory property. The samples which were treated by nitirc acid have a 9.7mmol/g ion exchange capacity for Li⁺.

LiFe_0.94Mg_0.04PO₄/C, LiFe_0.96Mg_0.02PO₄/C and LiFe_0.96Mg_0.04PO₄/C have been synthesized by a solid-state reaction using Li₂CO₃,FeC₂O₄·2H₂O,MgO,and NH₄H₂PO₄ as starting materials and C₆H₆O₆ as carbon source. X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy(SEM),transmission electron microscopy(TEM)and Fourier transform infrared spectroscopy(FTIR)were used to investigate the effect of Fe²⁺ or Mg²⁺ on the morphology and structure of the prepared materials. The electrochemical performances of different samples were characterized by galvanostatic charge/discharge test and electrochemical impedance spectroscopy(EIS). The results indicated that the crystal lattice parameters and the Li-Fe anti-site defects were reduced, whereas the content of conductive Fe₂P in non-stoichiometric lithium iron phosphate increased when Mg was doped, and LiFe_0.94Mg_0.04PO₄/C exhibited the highest discharge performance, rate capability and excellent cycle performance,whose initial capacities were 161.2mAh/g at 0.1C,and 74.7mAh/g at 20C and the retention rate was 97.3% at 20C after 500 cycles.

With acrylic acid and 501 ether macromonomer as raw materials,solid polycarboxylate superplasticizers were prepared by the bulk polymerization method. The effect of temperature,chain transfer agent dosage,initiator dosage,molar ratio of acid and ether and the drop-time on the performance of the products were investigated. The results indicated that the solid polycarboxylate superplasticizers,under the optimum polymerization conditions as the temperature was 70℃,the dosages of the chain transfer agent and the initiator were 0.35% and 1%,both based on the mass of the macromonomer,the molar ratio of acid to ether was 4:1 and the drop-time was 2h,showed excellent dispersion and slump-maintaining,and the initial fluidity of cement paste could exceed 315mm which still exceeded 320 mm after 1 hour. Finally,the molecular structure of the products was characterized using Fourier transform infrared spectroscopy(FTIR)analysis,and it verified the polymerization of the Acrylic acid and 501 macromonomer was carried out successfully.

Olefins are important industrial chemicals,but the energy consumption in their production is very large. In this work,[M₃(HCOO)₆](M=Fe,Co,Ni)were synthesized using solvothermal method and characterized by XRD,N₂-sorption,SEM. We studied the pore structure effect on their ethylene and propylene adsorption properties. In a fixed-bed gas separation apparatus,ethylene/propylene separation abilities of[M₃(HCOO)₆] series were studied under dynamic conditions. The results showed that the pore sizes in MOFs can be rationally tuned through metal substitution. Larger pore sizes will lead to higher ethylene and propylene adsorption capacities,but lower propylene/ethylene adsorption selectivity and separation efficiency. Smaller pore sizes will increase the propylene adsorption,thus improve their propylene/ethylene adsorption selectivity and separation ability. In this work,we show that metal substitution on[M₃(HCOO)₆] series can effectively increase the propylene/ethylene separation ability,and this strategy provides an idea for efficient separation of light hydrocarbons.

The polyvinylidene fluoride(PVDF)composite ultrafiltration membrane was prepared using semi-interpenetrating polymer network(semi-IPN)method. According to the membrane properties and its structure observed by SEM,the best conditions for building PVA/PVDF semi-IPN structure by acetalation of polyvinyl alcohol(PVA)and glutaraldehyde(GD)were that the addition of polyvinyl alcohol was 4.0%(mass percentage)and the ratio of glutaraldehyde to PVA was 0.5 in the casting solution. Performance of the semi-IPN structure composite membrane reached the best when the casting solution formula was PVDF/PVA/PVP/GD/NMP=16/4/3/2/75,with the flux=612.3L/(m²·h),the contact angle=48.3°,the BSA rejection=98.7%,the blasting pressure=1.0MPa,and the adsorption capacity of BSA 45.3μg/cm². The composition and structure of the membrane were characterized by X-ray photoelectron spectroscopy(XPS)and infrared analyzer(FTIR). After treating practical petrochemical wastewater for a month,the water flux was 144.4L/(m²·h),the removal rate of COD was 80.4%,and the turbidity removal rate was about 97.2%. Compared with the parameters of the membrane prepared by the formula without the semi-IPN structure,the PVA/PVDF composite membrane had larger water flux,enhanced hydrophilicity,higher anti-pollution and backwashing capacity and therefore the comprehensive performance of the membrane was increased significantly.

Halloysite nanotube(HNTs) is a new natural aluminosilicate nanometer material. It has many advantages,such as unique nano-tubular structure,high specific surface area,and high reactivity. In recent years,HNTs has had more and more important applications in the field of biomedical transport. In this paper,the structure and properties of HNTs were briefly introduced. The feasibility of HNTs application in biomedical field was analyzed. The researches and applications of HNTs in enzyme immobilization,biological imaging,biological scaffold,targeted transport of cytotoxic drugs and gene,and other aspects of the application,were illustrated emphatically. Compared with traditional inorganic nanomaterials,HNTs has many advantages in the field of biomedical applications such as good immobilization effect,easy chemical modification,high biocompatibility,low toxicity,and high selectivity. Finally,the challenges of the HNTs in the field of biomedicine were pointed out,including long medical results conversion cycle,high medical costs,and unexplained drug release mechanism. The prospects of the HNTs in a series of modern medical technologies,such as disease diagnosis,targeted delivery of drugs and follow-up treatment,were also discussed.

The raw material of rosin-type nucleating agent is a nature product with low cost,non-toxic,tasteless and high efficiency of excellent nucleation. It gradually becomes the modified agent of polyolefin resin that researchers are keened on. This paper summarized the recent advances on the nucleating agents of rosin and its derivatives for modifying some polyolefin resins,such as polypropylene,polyethylene,and the others. It is suggested that adding rosin-type nucleating agent is one of effective ways to modify the polyolefin resin. And the distinctions between the nucleating agent and traditional nucleating agent were also discussed,including its high temperature resistance,dispersion,environmental friendliness,and low cost. Meanwhile,the nucleation mechanism for decorating polyolenfin resin with rosin-type nucleating agent is discussed,and the solutions to poor dispersion problems were proposed,such as adding a certain amount of dispersant before extruding to granulate. Furthermore,using rosin type nucleating agent efficiently and exerting synergistic effects with a myriad of substances were introduced. Finally,the future development of rosin-type nucleating agent was proposed.

A new type of Gemini surfactant(Gemini-12)was synthesized with cheap materials such as itaconic anhydride(IAn),lauryl alcohol,1,4-butanediol and sodium bisulfite by the monoesterification,sulfonation and diesterification reaction processes. The optimal reaction conditions of the diesterification obtained via orthogonal experiments were:ratio of sodium lauryl sulfoitaconic monoester to 1,4-butanediol=2.30:1.00,and 1.0% p-methyl benzenesulfonic acid at 150℃ for 6.0h. The structures of intermediate products and Gemini-12 were confirmed by FTIR and ¹H NMR. Finally,the primary physico-chemical properties of Gemini-12 were characterized. The critical micelle concentration(CMC)was 1.38×10^-3mol/L,and the surface tension at CMC was 28.60mN/m;the efficient factor pC₂₀ was 3.14;CMC/C₂₀ was 1.91;the saturation adsorption Γ_CMC was 1.15mmol/m²;the area per molecule at interface was 1.44×10^-3nm²/mole;the standard free energy of micellization was -9.018kJ/mol and the standard free energy of adsorption was -31.22kJ/mol. The CMC of Gemini-12 decreased with the increase of the concentration of NaCl solution.

Using glucose(G)as the raw material,acyl chlorination reaction was carried out under the conditions of ice-water bath with acryloyl chloride to obtain acrylic acid glucose ester(AGE). With methyl allyl polyethenoxy ether(TPEG-2400),acrylic acid(AA)and acrylic acid, glucose ester were prepared by radical copolymerization. The effect of different conditions on the properties of polycarboxylate superplasticizer was discussed. The acrylic acid glucose ester and copolymers were characterized by FTIR. The optimal reaction conditions were as follows:the reaction temperature 60℃,the reaction time 3.5h,the mole ratios of methyl allyl polyoxyethylene ether,acrylic acid and acrylic acid glucose ester were 1:3:0.5. The experimental results showed that the modified polycarboxylate superplasticizer could keep the fluidity of 280mm within one hour. Comparison of the polycarboxylate superplasticizer without modification and the addition of glucose monomer onlyshowed that the modified polycarboxylate superplasticizer had a great improvement in dispersion and retention properties.

a water-in-water hydrophobically associating polyacrylamide was synthesized using acrylamide,2-acrylamido-2-methyl propane sulfonic acid and erucylamide propyl hydroxy sulfobetaine as raw materials by dispersion polymerization in salt solution. The obtained polymer was characterized by means of FTIR and TG. The basic properties,micro-properties,and macroscopic properties of the OWPAM emulsion were also investigated. The results showed that the obtained emulsion had high yields,better averaged particle size,and better stability with erucic acid CAB of 4.0% viscosity average molecular weight of 2.43×10⁶g/mol,and OWPAM emusion critical associating concentration(CAC)0.32%. At room temperature,flow velocity of 10.0m/s and concentration of 0.10%,the OWPAM solution drag agent was 72%,The viscosity of 0.5% OWPAM solution could be increased up to 160mPa·s with TR-1 concentration of 1.0%. The fracturing fluid had good heat resistance,shear resistance,viscoelastic,and suspended sand. The new fracturing fluid could completely break in 2h when APS concentration was 0.05%.

Large quantities of slag dumped in the open are contributing to the absence of recovery and utilization of valuable metals as well as potential environmental pollution to water and soil arisen by heavy metal contamination. The mineralogical characteristics and researches on recovering valuable metals from typical copper slag produced by pyrometallurgical process were summarized in the present work. The advantage and limitation of outstanding treatment methods which are presently performed to dispose of the slag for the recovery of iron and copper contained were analyzed and discussed,such as mineral separation,hydrometallurgical extraction,pyrometallurgical impoverishment,high temperature oxidation and high temperature reduction,etc. The prospective trends were predicted. The analyzing results obtained showed that the slow cooling followed by flotation and hydrometallurgical extraction are high effective method for recycling of copper contained in the smelting slag with a high content copper. Especially the process of high pressure oxidative acid leaching has excellent application prospect as it can inhibit the leaching of iron. Mineral phase reconfiguration for utilizing resource is effective to recover copper and iron in the slag with low content of copper. The process that calcium oxide is added into the molten slag prior to modification and cooling slow followed by flotation and magnetic separation is prospective to be applied,as the reason that copper and iron contained in the slag can be effectively recycled,and that flotation tailings can be directly used in building materials industry.

Nitrous oxide(N₂O)is a potent greenhouse gas and can result in the destruction of the ozone layer. N₂O emission from biological nitrogen removal in domestic wastewater treatment plant has aroused widely attention in recent years. To better understand the mechanism of N₂O production in denitrification,this review concisely summarized the pathways of N₂O production and the influencing factors affecting N₂O production,such as carbon source,C/N ratio,electron acceptor,dissolved oxygen(DO),pH,solid retention time(SRT)and nitrous oxide reductase inhibitors. Previous investigation indicated that,in some cases,electron competition among the four reduction steps in denitrification could be the ultimate cause of N₂O accumulation,and electron competition might cooperate with some other environmental factors,such as pH,to conduce the N₂O accumulation. This review then gave an introduction on the techniques of using electron transfer inhibitors to manipulate the electron acceptor(s) involved in denitrification and using redox mediators to provide fast using electron donors in denitrification,and discussed the possibility of applying both techniques to study the electron competition process. Finally,this review proposed that studying the carbon oxidation process and the nitrogen reduction process separately could be a strategy to investigate the electron competition process. This review is conducive to reveal the key factors leading to N₂O and other denitrification intermediates accumulation,and to provide operation strategies to reduce the N₂O emission during denitrification in wastewater treatment plant.

The factors affecting acid-catalyzed liquefaction of chitin were studied by single factor experiments. FTIR was used to examine the major functional groups of liquefied residues and products;SEM,XRD and TGA were employed to investigate the surface morphology,degree of crystallinity and thermostability of residues,respectively. A kinetic model was constructed and used to provide an insight into the relationship between reaction rate and residue content at different temperatures. The results indicated that a higher temperature,a larger catalyst dosage,or a longer reaction time was associated with a lower residue content. Kinetic studies revealed that a complex multistage reaction was involved in acid-catalyzed liquefaction of chitin,having an apparent activation energy E_a=34.5kJ/mol,a pre-exponential factor A=254.17s^-1,a mean enthalpy of activation △H_r=30.86kJ/mol,and a mean entropy of activation △S_r=-210J/mol. The reaction on the whole was endothermic and its apparent reaction rate constant increased with raising temperature. The reaction system changed orderly with the input of external energy.

To fight against global warming and control the CO₂ emissions,several factors influencing the kinetics of CO₂ adsorption during moisture swing technology are systematically analyzed to solve the problem of slow CO₂ adsorption rate and poor kinetic performance under ultra-low CO₂ atmosphere. The multiple influencing mechanisms of structure parameter,temperature and humidity on CO₂ adsorption kinetics were studied through experimental analysis and theoretical model. Firstly,the CO₂ adsorption membrane was prepared by phase inversion technique,and then the porous and heterogeneous membrane with controllable structure and adjustable functional groups was obtained after optimization and screening,through which the reversible adsorption of CO₂ was realized. In light of the complex mass transfer steps of CO₂ adsorption for heterogeneous adsorbents,the traditional Shrinking Core Model was modified to describe the CO₂ adsorption process and all resistance during CO₂ adsorption was obtained. Meanwhile,the effects of the structure parameters,temperature and humidity on total mass transfer coefficient and individual step(diffusion and reaction)were studied by experiments. The results showed that the product layer diffusion resistance dominated the total mass transfer during CO₂ adsorption,indicating that the optimization of the adsorbent should focus on reducing product layer diffusion resistance.

In order to reduce the cost of denitrification of thermal power units under the condition of satisfying the environmental emission standards,a calculation model of the denitrification cost for electricity generation was established for the selective catalytic reduction(SCR)denitrification system of a 350MW coal-fired unit. The cost of denitrification is divided into two parts:fixed denitrification cost for electricity generation and variable denitrification cost for electricity generation. The fixed denitrification cost for electricity generation includes depreciation cost,accounting cost,catalyst replacement cost,overhaul cost,labor cost,compensation price and other cost. The variable denitrification cost for electricity generation includes cost of electricity,cost of ammonia injection and cost of sewage. Taking denitrification cost for electricity generation as the evaluation index,the optimization model of denitrification system was established by using support vector machine and particle swarm coupling algorithm,and the whole load section was optimized for denitration system. The results show that the prediction model can accurately predict the denitrification cost for electricity generation,and the maximum correlation coefficient is 99.9011%,which is in accordance with the actual operation of the power plant. The amount of ammonia spray required after the model optimization is reduced to 0.1578t/h,and the denitrification cost for electricity generation is significantly reduced. The system economy is improved,which can be used to guide the economic operation of the power plant.

Aiming to solve the problem that coking wastewater was not in proportion for carbon and nitrogen nutrients,abundant in poisonous components and difficult to be anaerobic treatment,self-developed novel biological fluidized bed with three phases was employed as high loading aerobic pretreatment method for the coking wastewater. The investigation mainly focused on the performance of the proposed aerobic reactor. Moreover,variation of critical organic components in aerobic biological process was analyzed by UV-Vis absorption spectrum and GC-MS methods. The main results could be listed as the following. When the influent average COD concentration is 4818.9mg/L, ambient temperature is between 28℃ to 33℃ degree,dissolved oxygen is in the range of 1.0mg/L to 1.5 mg/L and MLSS is about 8.0 g/L,then the organic loading of the reactor is in the range of 3.53 to 3.74kgCOD/(m³·d),and phenol,benzpyrole and phenylamine in wastewater can be efficiently degraded. Average removal ratio of COD,phenols and SCN^-can be over 70%、99% and 80%,respectively. By significantly reducing concentration of poisonous organics such as phenols,SCN^-,CN^-,and so on,the inhibition bottleneck for subsequent anaerobic hydrolysis and aerobic nitrification processes can be relieved. The reason the preposition aerobic fluidized bed can act as a necessary guarantee for high efficient biological treatment for coking wastewater can be attributed to the enhanced mixing and mass transfer and high sludge concentration in the proposed reactor. Therefore,,because aerobic biological fluidized bed has good mixing and mass transfer efficiencies and high sludge concentration,employing it as a pretreatment biological unit process for toxic and refractory organic wastewaters together with high ammonium concentration has some technical advantages,or other,prepositioned aerobic biological fluidized bed is indispensable to guarantee highly efficient treatment of these wastewaters.

A novel and efficient heterogeneous photo-Fenton catalyst has been successfully prepared using co-precipitation method,in which the Fe₂O₃ particles were loaded onto the surface of opal. The catalyst was then used to degrade the Rhodamine B(RhB). The structural characterization of catalyst was analyzed by N₂ adsorption,X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectrometry(EDS),Fourier transform infrared spectroscopy(FTIR). The COD(chemical oxygen demand)removal and the influencing factors of degradation effect were analyzed,such as pH,temperature,catalyst dosage,H₂O₂ dosage and initial dye concentration. The results showed that the decolorization rate of RhB and COD removal were 96.49% and 50.51% respectively under agitation after 120min treatment with pH of 2.5,reaction temperature 30℃,dosage of catalyst 0.15g/L,dosage of H₂O₂ 9.0mmol/L and initial concentration of RhB 40.0mg/L. The first-order kinetic equation was fitted to the reaction process,and R²=0.98 under the optimal condition,which indicated that the reaction process obeys the first-order kinetic equation. The decolorization rate of RhB was still higher than 85% when the catalyst used for 5 times,which proved that the catalyst has a good reusability. Finally,the reaction process was analyzed and a possible photocatalytic mec hanism was proposed.

The photocatalysts of x%Ce-TiO₂/SiO₂(x=0,0.1,0.3,0.5,0.8,1,mass fraction)were prepared with Si(OC₂H₅)₄,Ti(OC₂H₅)₄ and Ce(NO₃)₃·6H₂O as precursors via a sol-gel method. The XRD date showed that thermal stability of TiO₂ can be improved by introducing Cerium and SiO₂ into it,and phase transformation from anatase to rutile can be inhibited effectively. The analysis results of XPS and FTIR showed that chemical bonds are formed between TiO₂ and SiO₂ by the appearance of Si-O-Ti and Si-O-Si bonds in 0.3% Ce-TiO₂/SiO₂. The result of SEM and BET showed that 0.3%Ce-TiO₂/SiO₂ has smaller particle size,more uniform size distribution and larger specific surface area(194.98m²/g) than pure TiO₂. The Rh B was used as the target pollutant,and effects of cerium content on photodegradation efficiency of Ce-TiO₂/SiO₂ were studied under the condition of ultraviolet light and visible light irradiation. The results showed that the TiO₂ 10% SiO₂ and 0.3% Ce has the best photo-degradation performance. The degradation efficiency could reach to 99% and 78% after reaction for 30min under the ultraviolet light and 180min visible light irradiation,respectively. Compared to P25(8%),the removal rate(41%)of TOC of 0.3%Ce-TiO₂/SiO₂ showed higher degaradation of phenol.