Volumn Content

The Chinese Journal of Process Engineering 2012 Vol.12 Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Numerical Simulation of Copper Flash Smelting Process with Rotarily Distributed Air CHEN Juo YIN Shu-gui ZHOU Jun    2012, 12 (1): 1-8.   Abstract （948）      PDF （557KB）（316）       Knowledge map    Save A modification scheme was put forward to change the straightly distributed air in the central jet distributor (CJD) concentrate burner into rotarily distributed air in copper flash smelting furnace, and simulations were carried out to investigate the distributions of velocity, temperature and concentration fields of both the gaseous and particle phases in two burner schemes. Comparison of two simulation results show that the rotarily distributed air is more conducive to improvement of the mixing and reaction process between the gas and particles, which will result in the increase of oxygen utilization by 4.5%, however, as small particles tend to be more easily affected by the rotarily distributed air, the dust generation rate will also increase in such a condition. Related Articles | Metrics Select Residence Time Distribution of Particles in a Bubbling Fluidized Bed with Their Continuous Input and Output GAO Wei ZHANG Ju-wei WANG Yin; HUANG Bo XU Guang-wen    2012, 12 (1): 9-13.   Abstract （1007）      PDF （242KB）（341）       Knowledge map    Save The characteristics of residence time distribution (RTD) of solid particles (Geldart B) with the pulse particle tracer approach in two cold rectangular bubbling fluidized beds (BFB) with continuous particle flow were experimentally investigated. The parameters tested were superficial gas velocity (U), feeding rate of particles (Gs), particle bed height (H) and particle size (dp), and the used tracer was coal particles. The results showed that Gs, H and dp were the major influential factors, while U affected little. The particle flow pattern in BFB reactor lied between those of the ideal plug flow reactor and completely stirred reactor (CSTR), it was close to the plug flow when the particle bed height was lower and Gs larger, whereas the flow was much closer to the full mixing flow of the CSTR at the higher particle bed height and smaller Gs. The averaged residence time of particles was calculated as the value of 9%~18% below of the plug flow for the design of BFB based on the present experimental data. Related Articles | Metrics Select Analysis and Optimization of Blade Parameters in Vertical Milling Classifier TONG Cong LI Shuang-yue QI Hai-jun REN Chao-fu    2012, 12 (1): 14-18.   Abstract （1095）      PDF （562KB）（407）       Knowledge map    Save Models of vertical milling classifier with different rotor blade spacings and tilt angles of installation were built, and their effects on the velocity field and classification efficiency of classifier simulated by CFD. Structural transformation in the spacing and tilt angle of classifier was tested, and the result showed that after transformation, the production of vertical milling classifier with rotor blade number of 48 and installing tilt angle of 5o was increased by 0.5~1 t/h compared with that with the rotor blade number of 72 and installing tilt angle of 0o. And the cyclic loading and energy consumption were reduced and the cost of device and product was lowered. Related Articles | Metrics Select Research on Performance of Wave-plate Mist Eliminators ZHANG Xiao-chen ZHANG Ming RUAN Guo-ling HU Kong-cheng    2012, 12 (1): 19-23.   Abstract （942）      PDF （245KB）（266）       Knowledge map    Save The influential factors on the separation property of wave-plate mist eliminator were studied with cold-state simulation experiments by using an air-water medium. The effects of operating conditions such as gas velocity and liquid droplet diameter and structural parameters such as the installation, geometry and spacing of the plate were examined. The gas velocity limit was controlled in 1~6 m/s, and the liquid droplet diameters from 50~80 mm, the plate was installed in horizontal and vertical directions, its geometry had V and W shapes, and the spacing was from 10~50 mm. The experimental results showed that there were some rules on the effects of influential factors such as gas velocity on the separation efficiency, and the spacing of 20 mm was the best arrangement. A reasonable empirical equation obtained by regressing the experimental data could predict experimental data within 10% error. A medium-scale experiment of desalination was also carried out to evaluate the separation property of the eliminator. Related Articles | Metrics Select Adsorption Properties of 2,4-Dihydroxybenzoic Acid on Three Anion Exchange Resins XIE Zu-fang LIU Guo-chao TONG Zhang-fa    2012, 12 (1): 24-30.   Abstract （1017）      PDF （296KB）（238）       Knowledge map    Save The adsorption properties of 2,4-dihydroxybenzoic acid by 717 (gel-type, strong base), D201 (macroporous-type, strong base) and D301R (macroporous-type, weak base) resins were studied through static and dynamic experiments. The results show that the maximum adsorption ability of 717 and D201 resins occurs at pH=4~11, and D301R resin at pH=3~9. At pH=5, 293~313 K and initial concentration of 2,4-dihydroxybenzoic acid of 0.6488~6.488 mmol/L, the adsorption isotherms of 2,4-dihydroxybenzoic acid on D301R, 717 and D201 resins obey Freundlich model, and their maximum equilibrium adsorption capacity is 2.98, 2.66 and 2.54 mmol/g, respectively (the adsorption has not reached saturation yet). The adsorptions are physical and spontaneous, exothermal processes. Pseudo first-order and pseudo second-order models were applied to correlate the kinetic experimental data. The former was more accordant with the experimental data than the latter. The 2,4-dihydroxybenzoic acid adsorbed on the three resins could be eluted by 100 mL 5%(w) NaCl+2%(w) NaOH solution quickly with elution rate reaching 99%. The adsorption performance of 2,4-dihydroxybenzoic acid on D301R resin was better than on that on D201 and 717 resins under the same conditions. Related Articles | Metrics Select Preparation of Molecularly Imprinted Polymer for Sulpiride and Its Adsorption Characteristics ZHANG Wei SHE Xu-hui FAN Hua-jun JIANG Zi-tao WU Kun-hong WANG Li-ping    2012, 12 (1): 31-37.   Abstract （968）      PDF （497KB）（310）       Knowledge map    Save Using sulpiride (SUL) as template, methacrylic acid (MAA) as function monomer, and ethyleneglycol dimethacrylate (EDMA) as cross linker, a molecularly imprinted polymer (MIP) was synthesized by bulk polymerization. Static adsorption and isothermal adsorption experiments were performed to study the influential factors on adsorption properties of the MIP to SUL by UV, FT-IR and SEM analysis. Adsorption mechanism of the MIP was also analyzed. The results showed that its best imprinting effect on SUL was observed when the volume of acetonitrile was 6 mL, molar ratio of SUL to MAA 1 to 4, and methanol-acetic acid (9:1, j) used as eluting agent. The MIP offered uniform, loose and porous structure with 79.12 mmol/g of maximum adsorption capacity and 3.76 of imprinted factor for SUL. The main recognition sites of MIP were cavities caused by three types of amino groups on amide, benzsulfamide and 1-methylpyrrolidine in molecular structure. The MIP had better specific adsorption and exhibited good recognition and selectivity to SUL and its analogues such as amisulpride and tiapride. Their specific adsorption rates were respectively 68.35%, 66.72% and 58.8%. Thus, the MIP could be used in separation and analysis for SUL drugs. Related Articles | Metrics Select Characteristics of Water Quenched Copper-containing Slag and Separation of Iron and Silicon from It ZHAO Kai CHENG Xiang-li QI Yuan-hong ZHEN Chang-liang SHI Xue-feng    2012, 12 (1): 38-43.   Abstract （1032）      PDF （492KB）（747）       Knowledge map    Save A mineralogical study of water quenched copper-containing slag was carried out with XRD, SEM, chemical analysis, etc. Fayalite is the major phase and copper exists in matte in the slag. The slag is amorphous, and its structure compact. The matte phase is not fully crystallized, its particle size is below 5 mm, iron and silicon exist mainly in fayalite, beneficiating method can not separate Fe and Si effectively. A new technology of rapid solid-phase reduction and high temperature smelting was proposed, and experiments were carried out. The experimental results show that the high copper and iron recovery rates can be achieved under the conditions of basity at 0.5, final smelting temperature of slag above 1300℃, smelting and separation temperature above 1350℃, and addition of additive, they are 93% and 87%, respectively. The iron and copper left in slag is less than 5% and 0.10% respectively. It means that the slag can be used as construction material, and the process can separate iron and copper, and the comprehensive utilization of copper slag can be achieved. Related Articles | Metrics Select Salting-out Extraction of Lactic Acid from Fermentation Broth WEI Bo-chao SONG Zhi-yuan SUN Ya-qin XIU Zhi-long    2012, 12 (1): 44-48.   Abstract （1162）      PDF （265KB）（543）       Knowledge map    Save Salting-out extraction was used for recovery of lactic acid from fermentation broth. The different hydrophilic organic solvents-inorganic salts systems were investigated for their extraction ability. The results showed that the K2HPO4-methanol and K2HPO4-ethanol systems appeared to be favorable. The partition coefficient and recovery rate of lactic acid reached up to 4.01 and 86.0% for the system of 25%(w) K2HPO4-26%(w) methanol, when the concentration of lactic acid was 167 g/L in the broth. For the system of 14%(w) K2HPO4-30%(w) ethanol, the partition coefficient and recovery rate of lactic acid reached up to 3.23 and 90.6%. The removal rate of glucose, cells and proteins reached 67.3%, 100% and 85.9%, respectively. Related Articles | Metrics Select Bacterial Pre-oxidation of Refractory Gold Concentrate from the High Altitude Areas and Cyanidation Leaching of Gold ZHANG Zhi-qian LIU Sheng-ming LI Chao LI Hong-xu WU Chao    2012, 12 (1): 49-53.   Abstract （835）      PDF （468KB）（205）       Knowledge map    Save Bacterial pre-oxidation of refractory gold ore from the high altitude areas was studied. The removal rates of Fe, S, As and cyanidation leaching rate of Au were examined under the different conditions. And the gold concentrate, oxidizing slag, and leaching residue were analyzed by XRD and SEM. The results indicated that the removal rates of Fe, S and As were up to 85% and the leaching rate of gold was 88.09%. Feasibility of bio-oxidation pretreatment in the high altitude areas was proved. Based on the experimental results, the bacterial oxidation mechanism of gold concentrates and acid solution neutralization were analyzed briefly. The bacterial oxidation of gold concentrate occurred under cooperative direct and indirect mechanism. Removal of the arsenic and heavy metal ions of liquid phase in the form of ferric arsenate and hydroxide precipitation was the main purpose of acid solution neutralization. Related Articles | Metrics Select Effects of Vanadium-containing Slag Calcium Roasting Conditions on Leaching Rate of Vanadium LI Xiao-jun ZHANG Run-ping XIE Bing    2012, 12 (1): 54-58.   Abstract （946）      PDF （320KB）（390）       Knowledge map    Save Based on the analysis of reaction mechanism of vanadium-containing slag (V2O3 8.07%) calcium roasting process, the effects of various factors on vanadium leaching rate were investigated by means of calcium roasting coupled with acid leaching. The results showed that various calcium vanadates namely CaV2O6, Ca3V2O8, CaV3O7 would form between V2O5 and CaO at 600~900℃. The acid leaching of roasted slag indicated that the mass ratio of CaO to V2O3 in the roasted slag played an important role in the roasting process. Vanadium leaching rate increased from 55.3% to 69.2% when the ratio was from 0.48 to 1.125, while the rate decreased when the ratio exceeded 1.125. When the roasting temperature increased from 750 to 825℃, the leaching rate from 56.3% to 69.7%. However, the slag roasted the temperature higher than 825℃ lead to the decrease of leaching rate. Vanadium leaching rate increased with the roasting time. The maximum rate was achieved when the roasting time was 2 h. With longer roasting time, the slag reacted further, leading to the decrease of vanadium leaching rate. Related Articles | Metrics Select Reaction Macrokinetics for Preparation of Sodium Dichromate from Barium Chromate and Sodium Hydrogen Sulfate TIAN Ying WANG Xue-kui GAO Yi-ying XU Hong-bin WANG Tie-feng    2012, 12 (1): 59-63.   Abstract （1047）      PDF （240KB）（339）       Knowledge map    Save The macrokinetics on preparation of Na2Cr2O7 from BaCrO4 and NaHSO4 was studied. The effects of stirring rate, H+ concentration and reaction temperature on BaCrO4 conversion rate were investigated. The results showed that the preparation of Na2Cr2O7 included that BaCrO4 was dissolved in an acidic aqueous solution to reactive formation of BaCr2O7, BaSO4 and Na2Cr2O7 formed from the reaction of BaCr2O7 with NaHSO4, and BaSO4 was crystallized to precipitation. The reaction temperature must be raised as high as possible, the stirring rate was kept at 400 r/min, the H+ concentration must be more than 0.01 mol/L and less than the H+ concentration when sodium hydrogen sulfate was in saturation. The parameters in the model were estimated, the activation energy was 41.029 kJ/mol, and the frequency factor 15978.51. The one-order kinetic model was obtained by analysis of experimental data, which was -ln(1-XA)=15978.51exp[-41.029′103/(RT)]t. Related Articles | Metrics Select Recovery of Organic Template from SBA-15 Using Supercritical Carbon Dioxide Extraction SU Guang-xun JIN Jun-su CUI Wen-guang LIU Hong-tao ZHANG Ze-ting    2012, 12 (1): 64-67.   Abstract （1032）      PDF （241KB）（259）       Knowledge map    Save The optimum conditions to recover organic template P123 (EO20PO70EO20) from SBA-15 using supercritical carbon dioxide extraction with cosolvents were studied in a 200 mL high pressure extraction vessel. The effects of cosolvent, extraction temperature, extraction pressure, and cosolvent flow rate on recovery rate were studied. The results showed that under the optimal operating conditions of methanol as cosolvent, extraction temperature 45℃, extraction pressure 27 MPa, cosolvent flow rate 4 mL/min, and extraction time 1.5 h, the recovery rate of template P123 was 73.7%. SBA-15 obtained by different methods was characterized. The results indicated methanol-modified supercritical carbon dioxide extraction was an efficient and environmental friendly method. The obtained SBA-15 maintained highly ordered framework. The recovery process of supercritical carbon dioxide extraction can avoid the structure shrinkage and silanol group removal caused by high thermal calcination. Related Articles | Metrics Select Characterization and Gasification Kinetics of Char with Different Particle Sizes under Gasification Conditions of Pulverized Coal SUN De-cai ZHANG Ju-wei ZHAO Yi-jun LIU Yun-yi YU Jian XU Guang-wen    2012, 12 (1): 68-74.   Abstract （963）      PDF （348KB）（269）       Knowledge map    Save Char samples with different averaged diameter particles were prepared from a given raw coal in a flat flame reactor which simulated the real gasification conditions of pulverized coal. Their physical structure was characterized and their CO2 gasification kinetics studied. The averaged specific surface area of small particle char was far lower than that of large one. Analyzing the experimental data of char CO2 gasification found that although the specific surface area of small char was lower than that of the large char, the small char had higher gasification reaction rate. This is because the large particle char contained lots of meso-pores and caused the inner diffusion limit to the gasification reaction. The random pore model was used to derive a gasification rate Ri. With the reaction rate Ri,s at steady-state under different temperatures, the intrinsic reaction rate of char CO2 gasification was expressed as Ri=1.243′103exp(-19243.5/T) g/(m2×min). Related Articles | Metrics Select Preparation of W/O Corn Oil Emulsion Using High Electrical Voltage Electrostatic Spray Method ZHANG Jun HE Hong-zhou MAO Lai-feng    2012, 12 (1): 75-80.   Abstract （845）      PDF （236KB）（267）       Knowledge map    Save The W/O corn oil emulsion is prepared by high electrical voltage electrostatic spray method. In the working ranges of flow rate of 2.8~15 mL/min and applied voltage of -5.2~-11 kV, the dispersed droplet diameters of prepared emulsion are measured using Winner99 particle image analyzer. The results show that the dispersed droplet size distribution of the emulsion prepared by electrostatic spray method is narrower than that of the emulsion prepared by stirring method. Under experimental conditions, the W/O emulsion with an average droplet size of 28 mm and a size distribution range of nearly 20~40 mm is obtained. The stability of emulsion prepared by electrostatic spray is obviously better than that by stirring method. The applied electrical voltage and spray flow rate have significant effects on the size and size distribution of emulsion droplets. With the increase of the voltage, the droplets become fine in size and uniform in size distribution. With the increase of flow rate, the spraying electrical current increases due to more charge transferred by droplets in unit time, whilst the charge density on droplets decreases, this eventually leads to enlargement of droplet size and broadening of droplet diameter distribution. Higher voltage and smaller flow rate will be helpful to obtain the emulsion with better stability. Related Articles | Metrics Select Coal Selection in 2500 m3 Blast Furnace of Xiangsteel MA Chao ZHANG Jian-liang Cheng-lin; YIN Jian HE Xin-jie WU Wei-jia    2012, 12 (1): 81-86.   Abstract （921）      PDF （457KB）（266）       Knowledge map    Save Based on the physical and process properties of 9 kinds of pulverized coal in Xiangsteel, including ash fusion point, grindability index, ignition point, explosibility, fluidity, combustibility and reactivity, all the properties of bituminite and anthracite coals are evaluated, and reasonable options recommended. It is concluded that (1) Hengda is the best kind of bituminite to be used in Xiangsteel blast furnaces, Weihua bituminite the next choice. Their combustion rates are both above 85%. Because of low sulphur content, combustion rate over 70%, high grindability, good fluidity and high ash fusion temperature, Yangyang, Xiangyindu and Xingxing anthracite are suitable to blast furnace injection. (2) In accordance with the principle of coal blending, two options are recommended: mixture of Hengda, Xiangyindu and Baisha, and mixture of Weihua, Xingxing and Yangyang. Related Articles | Metrics Select Alkylation of Benzene with 2-Chloropropane to Prepare Cumene with Chloroaluminate Ionic Liquids as Catalyst XIE Fang-ming LUO Guo-hua XU Xin CHEN Han    2012, 12 (1): 87-91.   Abstract （929）      PDF （271KB）（376）       Knowledge map    Save [Et3NH]Cl-2AlCl3 ionic liquid was used to catalyze the alkylation reaction of benzene and 2-chloropropane to prepare cumene. The effects of reaction conditions were investigated. The results showed that under the optimal conditions of molar ratio of benzene to 2-chloropropane were 3.3, amount of catalyst 10% of benzene mass, and reaction temperature 55℃, the conversion rate of benzene could reach 29.38% and the selectivity of cumene was 90.60%. The [Et3NH]Cl-2AlCl3 ionic liquid could be recycled for 5 times. Related Articles | Metrics Select Preparation of Metallization Pellets with BF Gas Dust and Converter Sludge HE Huan-yu TANG Zhong-yong PEI Wen-bo WANG Hai-hua    2012, 12 (1): 92-96.   Abstract （1013）      PDF （575KB）（359）       Knowledge map    Save Experimental study on preparation of metallization pellets with BF gas dust and converter sludge was carried out. Their chemical composition, phase, particle size distribution and bulk density were analyzed, and the effects of reduction temperature, reduction time and C/O on the metallization were investigated. The results showed that iron oxide, flux and carbon had high content in the dust and sludge, which were in uniform distribution and good contact. Harmful element zinc in the form of ZnFe2O4 existed in the mixture phase of other oxides. Their bulk density was small (<1.5 g/cm3), and they contained numerous coarse particles with more than 1.5 mm diameter. With increasing of reduction temperature, prolonging of reduction time and reducing of C/O ratio, the metallization rate and dezincing degree went up, and the effect of temperature was the most significant. 85% metallization rate and 90% dezincing degree were achieved when C/O=1.0 under reduction temperature above 1220℃ and reduction time over 30 min. Related Articles | Metrics Select Techno-economic Analysis of Cellulosic Ethanol JIANG Qin SUN Ya-qin TENG Hu XIU Zhi-long LIU Chun-zhao    2012, 12 (1): 97-104.   Abstract （936）      PDF （274KB）（363）       Knowledge map    Save The process technology for fuel ethanol production from corn straw was investigated, and then the techno-economic and sensitivity analysis were conducted on an annual capacity of 50000 t ethanol. The simulation shows that the energy consumption of crude distillation tower is obviously low when the ethanol concentration in fermentation broth is higher than 4%(w). Direct fixed capital of the process is about 137 million yuan and the lowest cost for cellulosic ethanol is 8425 ￥/t. The annual by-product output of 37500 t CO2 and 215 t fusel oil would bring additional revenue 23.86 million yuan. The economic sensitivity analysis shows that the price of cellulase is relatively sensitive to the production cost of ethanol, and the recovery and utilization of CO2 are obviously favorable for profit of process. Related Articles | Metrics Select Research on Superparamagnetic Polyvinyl Acetate Microspheres for Affinity Separation of Nattokinase KONG Peng XIE Yu-chun WEI Xue-tuan XU Lin YANG Liang-rong LI Peng-fei ZHOU Hua-cong LIU Hui-zhou    2012, 12 (1): 105-111.   Abstract （958）      PDF （320KB）（371）       Knowledge map    Save Micro-size magnetic polyvinyl acetate microspheres were prepared by a modification suspension polymerization, the magnetic beads were further modified with hydrolysis and aminization reactions, and magnetic affinity microspheres suitable for nattokinase purification were obtained by covalent immobilization of p-aminobenzamidine to the amino-modified magnetic beads by the glutaraldehyde method. The properties of magnetic beads were examined by SEM, XRD, FT-IR and VSM. The results showed that these magnetic beads were typically superparamagnetic and the specific saturation magnetization of ligand-attached magnetic beads was 32.4 emu/g. It took only 40 min to reach adsorption equilibrium and less than 15 min to achieve desorption equilibrium. The purification factor and the recovery rate of enzyme activity were 10.3 and 73.4%, respectively. The purified nattokinase gave a single sharp band on SDS-PAGE. Related Articles | Metrics Select Pareparation of Cyanobacteria-carried Tebuconazole and Its Release Behavior AI Li-juan REN Tian-rui WANG Quan-xi XU Wen-ping    2012, 12 (1): 112-118.   Abstract （1030）      PDF （574KB）（206）       Knowledge map    Save The controlled release formulation of tebuconazole (Teb) was prepared using microcystis (MC) as carrier and carbopol resin as matrix. The MC powder and release formulation were characterized by XPS, FT-IR, SEM, etc. Its adsorption and release behavior are measured by ultraviolet visible spectrophotometer. At 30℃, the adsorptive capacity of Teb is 18.68 mg/g in ethnol and 20.1 mg/g in isopropanol, respectively. The adsorption density is 1.04×109 Teb molecules per MC. The controlled release formulation of 10% carbopol release rate is 74.5% for 204 h in ethanol-water solution (1:1, j). Related Articles | Metrics Select Drug Release Mechanism of BSA-loaded Electrospun Fibers by AFM XU Peng LI Wei ZHOU Hua-cong LIU Hui-zhou    2012, 12 (1): 119-124.   Abstract （863）      PDF （480KB）（268）       Knowledge map    Save Experiments were carried out to study the drug delivery mechanism of bovine serum albumin (BSA) loaded chitosan (CS)-poly(ethylene oxide) (PEO) nanofibers and poly(L-lactic acid) (PLA)-CS nanofibers. Atomic force microscope (AFM) was used to observe the degradation and swelling behavior of fibers in PBS solution. As seen from the SEM images of scaffolds and drug release profiles, their BSA delivery mechanisms were different. 96% BSA was released from CS-PEO nanofibers after 10 h and the structure was almost totally degraded in 1 d. AFM images showed a distinct degradation process of CS-PEO fiber and fiber diameter increasing from 0.727 to 1.43 mm from 10 to 120 min. So BSA releasing was mainly controlled by the rapid degradation of CS-PEO fibers. On the contrary, no obvious degradation was observed in the AFM or SEM images of PLA-CS nanofibers. The fiber diameter increased from 1.9 to 2.8 mm from 1 to 30 d, and the amount of BSA in solution was less than 50%. It demonstrated that the BSA delivery of PLA-CS fibers depended on the drug diffusion process. Related Articles | Metrics Select Extraction and Characterization of Serotransferrin from Monopterus albus WANG Bo-wen REN Tian-rui DONG Ya-ming    2012, 12 (1): 125-130.   Abstract （1000）      PDF （292KB）（210）       Knowledge map    Save The crude extraction of serum protein in Monopterus albus obtained by salting was purified by ion exchange chromatography. By means of biological mass spectrometry, the protein was identified as serotransferrin, which was the serum transferrin. Its molecular weight, surface morphology and secondary structure were characterized by SDS-PAGE, atomic force microscopy and circular dichroism, respectively. The results show that the molecular weight of serotransferrin is 74 kDa, its content 0.750 mg/mL, including a-helix 29.8% and b-fold 6.6%. Related Articles | Metrics Select Research on Basic Characteristics of a Microbial Fuel Cell with Chlorella vulgaris Biocathode WU Xia-yuan SONG Tian-shun ZHI Yin-fang ZHOU Chu-xin YU Jun-jie ZHU Jun-yao    2012, 12 (1): 131-135.   Abstract （860）      PDF （313KB）（223）       Knowledge map    Save Using the modified microbial fuel cell (MFC) with a tubular photo-bioreactor for a cathode compartment as the experimental model, the electricity generation of MFC, catholyte dissolved oxygen (DO), and growth of Chlorella vulgaris in the cathode chamber were investigated under different light-dark cycles, when C. vulgaris was added in the chamber. The results showed the electricity generation of MFC with C. vulgaris biocathode was obviously enhanced, the maximum power density reached 27.5 mW/m2 in constant illumination group, and 24.4 mW/m2 in light-dark group. The analysis of DO and cyclic voltammetry curve proved that DO was the key factor affecting the electricity generation, and the DO value was more stable in constant illumination group, but lower than that in light-dark group in lighting phase. Moreover, no poison against the cultivation of C. vulgaris was found in the chamber. C. vulgaris grew well, especially in light-dark group. It is suggested that the MFC with C. vulgaris biocathode is better operated under light-dark cycle, and the period of cycle prolonged. Related Articles | Metrics Select Synthesis of Cu2O Microparticles by Precipitation Method and Its Application in (CH3)2SiCl2 Synthesis LIU Jie WANG Ying-li SONG Lian-ying CHE Hong-wei ZHANG Wei-dong SU Fa-bing    2012, 12 (1): 136-141.   Abstract （837）      PDF （1015KB）（390）       Knowledge map    Save Spherical Cu2O particles with three size ranges of 0.10~0.15, 0.5~1 and 1~2 mm were synthesized by precipitation method. The particle samples were characterized. Their catalytic properties in (CH3)2SiCl2 synthesis via Rochow reaction were investigated. The results showed that the size of Cu2O microparticles as model catalyst has a substantial effect on the (CH3)2SiCl2 selectivity, but no obvious effect on the Si conversion rate (about 12%). The (CH3)2SiCl2 selectivity over Cu2O microparticles with the size ranges of 0.10~0.15, 0.5~1 and 1~2 mm were 86.48%, 80.65% and 74.31%, respectively. Surface morphology of Si and contact mass at different stages shows that the carbon deposition is related to the catalyst size. The smaller particles are more effective for (CH3)2SiCl2 synthesis. Related Articles | Metrics Select Preparation of Ag@AgCl-TiO2-Flyash Microspheres Composite Photocatalyst and Its Photocatalytic Property under Visible Light GUO Ling-kun LU Jun ZHOU Song WANG Dong-mei XU Guang-qing ZHENG Zhi-xiang    2012, 12 (1): 142-147.   Abstract （787）      PDF （1627KB）（217）       Knowledge map    Save Ag@AgCl nanoparticles were loaded on the surface of flyash microspheres (FMS) by ion-exchange method to prepare Ag@AgCl-FMS composite support, then nano-TiO2 thin film was coated on it by hydrolysis precipitation with TiCl4 solution as precursor. After annealing at 500℃ for 2 h, the Ag@AgCl-FMS-TiO2 composite photocatalyst was obtained. Its microstructure, crystalline structure and photocatalytic properties under visible light were characterized. The results show that the TiO2 thin film on the substrate is uniform and complete. After calcining at 500℃, the material contains of 90% anatase phase and 10% rutile. The composite modified by Ag@AgCl nanoparticles exhibits high photocatalytic activity under visible light, which is caused by the surface plasmon resonance effect of Ag@AgCl. The degradation rate of methyl orange solution can reach 99% after 80 min irradiation under 250 W metal halide lamp. The photocatalyst also shows great stability. Repeated experiments show that the degradation rate of methyl orange solution can still reach 85% after 5 times of using. Related Articles | Metrics Select Preparation of Iron-doped MEL Zeolite and Its Performance of Catalytic Decolorization CHENG Yue PAN Shun-long JIAO Chuang WANG Jing    2012, 12 (1): 148-153.   Abstract （983）      PDF （470KB）（232）       Knowledge map    Save MEL zeolite was synthesized by hydrothermal method with a molar ratio of SiO2:TBAOH:H2O at 1:0.35:53. Fe doped composite catalyst based on the MEL zeolite carrier was prepared by mechanical mixing method. The catalyst samples were characterized. The effects of initial concentration of the dye wastewater, aqueous solution pH, amount of catalyst and H2O2 used, and reaction time on the degradation rate of dye wastewater were investigated. The results showed that the decolorization rate was 97.8% under the optimal conditions of dye concentration at 30 mg/L and pH value at 6, catalyst dosage at 3.75 g/L, 30%(w) H2O2 amount at 37.5 mL/L and reaction time was 2.5 h, respectively. Related Articles | Metrics Select Research on Curing of a Silicon-containing Arylacetylene Resin with Nickelous Diacetyl Acetonate LIU Hai-fan DENG Shi-feng HUANG Fa-rong DU Lei    2012, 12 (1): 154-159.   Abstract （1103）      PDF （304KB）（199）       Knowledge map    Save The curing reaction of silicon-containing arylacetylene resin (PSA) with nickelous diacetyl acetonate (NIAA) was studied, the curing behavior was characterized by gelation time and DSC analysis, curing kinetic parameters were calculated, the curing was traced by FT-IR. The results indicated that the catalytic effect of NIAA on PSA resin was obvious. When 0.2%(w) nickelous diacetyl acetonate was added in the resin, the apparent activity energy of curing reaction was decreased from 121.2 kJ/mol for PSA resin to 104.2 kJ/mol for PSA-NAA resin and the initial curing temperature decreased by 35℃. Glaser coupling, Strauss coupling, cyclotrimerization and Diels-Alder reaction occurred at different cuing stages of PSA-NIAA resin. The cured PSA-NIAA resin possessed excellent thermal stability. The temperature at 5% weight loss and char yield at 1000℃ of the cured resin with 0.2% NIAA were 620℃ and 87.8% under nitrogen, respectively. Related Articles | Metrics Select Improvement in Anti-oxidation of Two-step Dipping Graphite with Different Solutions DENG Ya-li ZHANG Xiao-meng Lianqi Wei YE Shu-feng CHEN Yun-fa    2012, 12 (1): 160-165.   Abstract （1050）      PDF （909KB）（254）       Knowledge map    Save A two-step dipping method was used to treat graphite with two solutions for improving its oxidation resistance. One dipping solution was mainly composed of magnesium chloride, aluminum hydroxide, phosphoric acid and another one borax, sodium tripolyphosphate, titanium dioxide. The composition and structure and mass change of the dipped graphite were analyzed by SEM, TG-DTA and XRD. The results showed that the mass loss of dipped graphite sample was less than 10% in air at 1150℃ for 1 h and the oxidation resistance was increased by 60% compared with untreated blank sample. The treated sample had flat surface, compact structure and clear edge after high temperature treatment, which was different from blank sample. The two kinds of dipping solution in high temperature formed glass polymer which was attached on the surface and pores of graphite, playing the role of oxidation resistance. Related Articles | Metrics Select Corrosion Behavior of ZrO2(f)-NiFe2O4 Inert Anode in Cryolite Molten Salt HUA Zhong-sheng YAO Guang-chun LONG Xiu-li WANG Hai-chuan HAN Zhao XIAO Sai-jun    2012, 12 (1): 166-171.   Abstract （926）      PDF （769KB）（196）       Knowledge map    Save NiFe2O4 spinel was synthesized via solid-state sintering technology using NiO and Fe2O3 as raw materials, and ZrO2(f)-NiFe2O4 inert anode was prepared by adding ZrO2 fibers [ZrO2(f)] into NiFe2O4. The static thermal corrosion rate and electrolytic corrosion rate of inert anode samples in cryolite molten salt were measured by weight-loss method, and their corrosion mechanism was examined by SEM, EDX and XRD analysis. The experimental results indicate that the porosity of anode samples is increased from 4.9% to 5.8% with the increase of ZrO2(f) from 0 to 4%(w), which leads to the increase of static thermal corrosion rate from 3.8 to 4.3 mg/(cm2×h). The dissolution reactions of oxides in cryolite molten salt are inhibited in the electric field. The electrolytic corrosion rate of anodes samples containing 3%(w) ZrO2(f) is 2.2 mg/(cm2×h), which is much lower than its static thermal corrosion rate, and both corrosions are controlled by physicochemical dissolution. ZrO2(f) has excellent stability in cryolite molten salt at high temperature, and can be used for the reinforcement of NiFe2O4 based inert anodes in aluminum electrolysis. Related Articles | Metrics Select Research on a New Type Immobilized ZnO Photocatalytic Membrane Reactor SUN Guo-tong HU Peng BAI Liu-yang YUAN Fang-li    2012, 12 (1): 172-176.   Abstract （1186）      PDF （288KB）（200）       Knowledge map    Save Porous membrane was sintered with the assembly of ZnO nanorods produced by RF plasma, and a new photo-catalytic membrane reactor established using the produced porous membrane. The membrane sintered from 400℃ to 800℃ show that the size of its pores decreases with the increase of sintering temperature. The membrane sintered at 600℃ shows better porous structure. The photocatalytic degradation of methylene blue (MB) in aqueous solution was examined by traditional photocatalytic suspension reactor and newly built membrane reactor. The photocatalytic reaction rate increases with the increase of the ZnO, and reaches the maxima when the amount of ZnO is 0.05 g corresponding to 100 mL 20 mg/L MB solution. The reaction rate in the membrane reactor increases with the increase of dosage of the solution. The new membrane reactor shows great increase in supply of oxygen for photocatalytic reaction. Related Articles | Metrics Select Upconversion Luminescence of Ho3+ Doped NaYF4 Powder at 828 nm Laser Excitation WANG Ya-jing ZHANG Zheng XIAO Lin-jiu XIE Ying;    2012, 12 (1): 177-180.   Abstract （945）      PDF （365KB）（232）       Knowledge map    Save Trivalent Ho3+-doped NaYF4 up-conversion luminescence powder was synthesized. The effects of heat treatment temperature and concentration of Ho3+ on its structure, morphology and luminescent behavior were examined by XRD, FT-IR, EDX and upconversion luminescence. Characters are studied on the synthesis temperature and concentration. The strongest emission was obtained under the excitation of 828 nm laser when annealing temperature was 900℃ and Ho3+ concentration 0.7%(mol). Upconversion luminescence of yellow and blue light emissions was obtained under the excitation of 828 nm diode in NaYF4:Ho3+ before annealing, strong green was obtained after annealing at 700℃. The mixed crystals of phases α and b appeared after annealing at 400℃, and the pure phase b appeared after annealing at high temperature. The upconversion mechanisms are green, yellow and blue emissions corresponding to the transitions of 5F4,5S2?5I8, 5I5?5G6 and 3K8,5F3?5I8, respectively. Related Articles | Metrics Select Solid-Liquid Suspension in a Vertical Three-impeller Stirred Tank LI Yong-gang HUANG Xiong-bin;    2012, 12 (2): 181-186.   Abstract （1012）      PDF （241KB）（254）       Knowledge map    Save In order to improve the related efficiency in a storage tank, the solid-liquid suspension by three CBY III impellers [0.174 m diameter (D)] was studied. The three CBY III impellers were symmetrically fixed in a stirred tank with the diameter (T) of 2 m and height of 0.8 m. The optimum installing location and height of agitators were determined by analyzing the deposition area and just-suspension blade tip speed for glass beads of average 100 mm. The results show that the minimum just-suspension speed appears at 0.285R (R, the radius of tank, m) away from the tank wall, and the liquid level of 0.3T is superior to the situations of 0.2T and 0.25T, meanwhile the liquid level between 0.2T and 0.3T has only weak influence on power consumption. The power consumption of vertical three-impeller stirred tank is 2.8 times as that of standard stirred tank (single vertical agitator), but a vast of manufacturing cost can be saved. Compared with the three side-entering agitators, the vertical three-impeller agitation can save 20% of the energy when solids have 95% suspension, and installation and maintenance are very convenient and concise. It can be concluded that the vertical three-impeller agitation has an extensive application prospect in industrial storage tanks. Related Articles | Metrics Select Effect of Indole on Hydrodesulfurization Performance of NiMo/g-Al2O3 Catalyst in a Slurry System LI Wei-kun XIANG Hai-ding WANG Tie-feng    2012, 12 (2): 187-193.   Abstract （868）      PDF （505KB）（163）       Knowledge map    Save Hydrodesulfurization (HDS) performance of the presulfurized hydrogenation catalyst NiMo/g-Al2O3 was studied using dibenzothiophene (DBT) as model compound with and without addition of 1000 mg/L indole (based on N) under 300℃ and 4.5 MPa. Sulfur content and species concentration were measured using micro-coulometric analyzer and gas chromatography-mass spectrometry, respectively. The fresh and used catalysts were characterized by BET, XRD, TEM, TPD and TGA. The results showed that the addition of indole slightly increased the reaction rate in the activation period, but significantly decreased the rate in the subsequent stable reaction period, leading to an overall decrease in desulfurization rate from 70% to 58%. The used catalyst did not change in surface topography and crystalline structure compared with the fresh catalyst, but showed an increase in specific surface area. The addition of indole caused 12% decrease in the catalyst pore size and 50% increase in coke formation, and significantly deceased the production of cyclohexyl benzene, indicating that the hydrogenation desulphurization route was suppressed. Related Articles | Metrics Select Alkylation of Isobutane with Ionic Liquid-Triflic Acid Coupled Catalyst WANG Peng ZHANG Zhen LI Hai-fang ZHANG Peng LAN Ling ZHAO Guo-ying    2012, 12 (2): 194-199.   Abstract （1215）      PDF （243KB）（367）       Knowledge map    Save A series of task specific ionic liquids based on imidazolium and pyridine with BF4-/CF3SO3- anion were synthesized through quaternary ammonium metathesis and protonation reaction. The above ionic liquids coupled with triflic acid were applied to catalyze the isobutane alkylation. Excellent alkylate quality with high C8 selectivity (81.8%), the ratio TMP to DMH at 8.36 and high research octane number 95.3 were obtained by tuning the type and content of ionic liquids. The coupled catalyst can be recycled for six times without significant loss of activity. Related Articles | Metrics Select Study on Leaching of Cobalt White Alloy by Acidithiobacillus ferrooxidans HU Guo-hong XIAO Li FANG Zheng ZHONG Hui    2012, 12 (2): 200-205.   Abstract （778）      PDF （293KB）（214）       Knowledge map    Save Acidithiobacillus ferrooxidans (A.f) was used for leaching of the hard cobalt white alloy. The experiments determined the optimum pH value and temperature in the presence of A.f to be 2.0 and 30℃, respectively. Three modes of treatment of the bacteria, which are directly inoculated with 107 cells/mL in 9K culture medium, dispersed to 107 cells/mL in iron-free 9K culture medium and beforehand adapted by the alloy and collected by centrifugation, were used. The result showed that for the first mode, it took 6 d to finish the leaching of cobalt and 8 d for copper with decrease in number of the bacteria in leaching. For the second one, it needed 3 and 7 d to dissolve cobalt and copper out, respectively, and accompanied decrease in the bacteria. And for the third one, the modified A.f could be increased to 108 cells/mL, and the leaching of two metals was for 2 d and 5 d, respectively. In the leaching process, pH value increased first and then decreased. The electric potential increased with the leaching of copper. With the bacteria which were beforehand adapted by the leaching of cobalt white alloy, its leaching residue contained a little ammonium jarosite and the leaching rates of cobalt and copper were 99.50% and 99.0%. The leaching mechanism of copper in cobalt white alloy by A.f was the indirect effect. Related Articles | Metrics Select Measurement of CO2 Solubility in Tributyl Phosphate CHEN Hao TANG Qing; TU Wei-xia BAO Wei-jun LI Shao-peng    2012, 12 (2): 206-211.   Abstract （1056）      PDF （241KB）（212）       Knowledge map    Save The solubility of CO2 in tributyl phosphate (TBP) solvent was measured in a temperature range of 303.15~363.15 K and gas pressure of CO2 up to 4.5 MPa by the constant volume method. The results showed that the solubility increased with the augment of CO2 gas pressure and decreased with the rising of equilibrium temperature. GC/MS and FT-IR analysis results indicated that the capture process of CO2 by TBP could be regarded as physical absorption. The Henry's coefficient which was obtained by fitting of the experimental data was well consistent with the Henry's law. It confirmed that there was no chemical change during the adsorption process. Comparing the absorption capacity of TBP with other solvents, the CO2 solubility in TBP was 1.4 times higher than that in ethanol and 0.2 times higher than that in N-methyl-2-pyrrolidone under the same conditions. Related Articles | Metrics Select Dissolution Behavior and Kinetics of Fine Silica Powder in Dilute Alkaline Solution ZHANG Jin-liang GUO Zhan-cheng; ZHI Xin TANG Hui-qing    2012, 12 (2): 212-217.   Abstract （1055）      PDF （570KB）（502）       Knowledge map    Save The dissolution behavior and dissolution kinetics of fine SiO2 powder in dilute alkaline solution were studied. The effects of initial concentration of NaOH, reaction time and reaction temperature on the dissolution rate of fine silica powder were investigated. XRD was used to analyze the phases of fine silica powder and leaching residue. The results demonstrated that SiO2 dissolution rate increased with initial concentration of NaOH and reaction temperature. Dissolution apparent activation energy of the amorphous SiO2 of fine silica powder in dilute NaOH solution was 18 kJ/mol. Dissolution reaction was controlled by diffusion. Related Articles | Metrics Select Co-extraction of Rare Earth and Iron from Baogang Tailings ZHANG Li-qing ZHAO Ling-yan ZHOU Hua-feng YUAN Ben-fu    2012, 12 (2): 218-222.   Abstract （964）      PDF （236KB）（207）       Knowledge map    Save A novel dissolving-extraction process of Baogang tailings in the dilute sulphuric acid and then dilute hydrochloric acid was studied. The effects of reaction temperature and sulfuric acid concentration on dissolution rate of the rare earth and iron were investigated and the total amount of rare earth in the acid dissolution of Baogang tailings was determined by spectrophotometry. The leaching rate of rare earth was less than 8% and the leaching rate of iron higher than 94% in the sulfuric acid dissolution. Fe3+ in sulfuric acid dissolution was reduced to Fe2+ by industrial scrap iron. FeSO4 was extracted by ethanol at room temperature. Its purity was 98.21% and the over-all recovery rate of iron in the tailings 89.51%. The grade of REO in the dilute hydrochloric acid insoluble residue was 43.60% and their total recovery rate 78.82%. This study provides a new method for extraction and separation of rare earth and iron from Baogang tailings. Related Articles | Metrics Select Adsorption Performance of Ionic Liquid [BPy]Br Immobilized on Activated Carbon to SO2 WEN Li-jing TIAN Jin-ping LV Yong-kang LI Bing-zheng MA Yan    2012, 12 (2): 223-226.   Abstract （895）      PDF （206KB）（111）       Knowledge map    Save The ionic liquid [BPy]Br was immobilized onto activated carbon (AC) via a facile incipient impregnation method. The SO2 adsorption/desorption performances of the immobilized ionic liquid were evaluated, and high SO2 adsorption capacity and rate achieved. Its capacity reached 49.5 mg/g with a N2/SO2 mixture gas containing 3300 mg/m3 SO2. The [BPy]Br/AC system could be reused for many adsorption/desorption cycles. The second adsorption rate reached 96.83%. The immobilized IL structure was determined. The immobilization resulted in the increase of the volume of pores small than 4 nm, the most noticeable change was in the size range of pores from 0.5 to 3 nm. After adsorption, the surface area decreased 47.5% with 29.5% decrease in the volume of microspores. Related Articles | Metrics Select Mechanism of Solid State Reaction between CaCO3 and MoO3 ZHU Hang-yu LI Zheng-bang WANG Jin-qing YANG Hai-sen    2012, 12 (2): 227-230.   Abstract （1004）      PDF （285KB）（308）       Knowledge map    Save Solid state reaction between CaCO3 and MoO3 was studied using non-isothermal thermal analysis method. On the basis of TG curve and extent of reaction, the chosen 13 solid reaction mechanism functions were fitted respectively. The Coats-Redfern method used for model fitting and kinetic parameter was calculated by slope and intercept. The results indicate that the reaction between CaCO3 and MoO3 begins at 450℃, its reaction mechanism belongs to random nucleation and growth with integral form g(a)=-ln(1-a), the apparent activation energy is determined to be about 170.2 kJ/mol with pre-exponential factor of about 1.3′107 s-1. Related Articles | Metrics page Page 1 of 5 Total 174 records First page Prev page Next page Last page