The Chinese Journal of Process Engineering

Recent Advance in Biomimetic Modification of Membranes with Biomolecules and Their Derivatives

Mingbo JI Jianquan LUO Xiangrong CHEN Yinhua WAN

Chin. J. Process Eng.. 2017, 17(6): 1109-1118. DOI: 10.12034/j.issn.1009-606X.217144

Asbtract ( )

PDF (1252KB) ( )

References | Related Articles | Metrics

Biomimetic modification of polymeric membranes with biomolecules and its derivatives is an effective approach to enhance the hydrophilicity, biocompatibility, antifouling performance and specific selectivity of separation membranes. In this review, the structures and properties of some biomolecules and their derivatives, such as chitosan, heparin, phosphorylcholine and dopamine, are systematically introduced at first. Then various biomimetic modification methods are reviewed. Finally, the applications of modified membranes are briefly summarized.

Research Advances in Acidity Characterization of Acid Catalysts

Liuyang WANG Guoying ZHAO Baozeng REN Suojiang ZHANG

Chin. J. Process Eng.. 2017, 17(6): 1119-1126. DOI: 10.12034/j.issn.1009-606X.217148

Asbtract ( )

PDF (446KB) ( )

References | Related Articles | Metrics

Acid catalyst has been widely used and well-studied in chemical process and their catalytic activities are normally dictated by their acidities. Determination of acidity of acid catalyst, such as type, amount (concentration), and strength, are the great significance for achieving desired results of catalytic reactions. In this mini review, the characterization methods for acid type, acid amount, acid strength and their recent progresses were summarized, and the merits and disadvantages of each method were also reviewed with specific focus on the progress of the three characterization methods in acid type, structure and application of the catalysts. It is of great significance to help readers fully understand the mechanism of acid catalysis and select suitable catalysts.

Advances on Hydroacylation Reaction Catalyzed by First-row Transition Metals

Ting LI Deping ZHU Baohua XU

Chin. J. Process Eng.. 2017, 17(6): 1127-1133. DOI: 10.12034/j.issn.1009-606X.217177

Asbtract ( )

PDF (726KB) ( )

References | Related Articles | Metrics

Recently, the non-noble transition metals show an increasingly enormous application potential in homogeneous catalysis due to its relatively low cost and high abundance. And they are considered as promising catalysts which could serve as an alternative to the noble metals. The review summarizes the advances in hydroacylation, the addition of a formyl C?H bond across an unsaturated bond C X (X=C, O), catalyzed by first-row transition metals. And challenges focusing on scope of substrates, catalytic reactivity and selectivity, even the mechanism insight into the transformation are still worthy of exploration.

Heat Transfer Enhancement of Syrup Vertical Falling-film Evaporation by Spiral Inserts

Deqi PENG Lanwei CHEN Haisong LUO Tianlan YU Kang CHEN Hao LI Yuye HAN

Chin. J. Process Eng.. 2017, 17(6): 1134-1139. DOI: 10.12034/j.issn.1009-606X.217133

Asbtract ( )

PDF (470KB) ( )

References | Related Articles | Metrics

The new form of vertical single tube steam-syrup falling film evaporation experimental platform was built to study the heat transfer performance of inserting the specific structure and technological parameters’ spiral in tube for the viscous syrup falling film evaporation, and conducting the 4 h comparative syrup falling film evaporation experiment for added and no added spiral. The results showed that inserting spiral has obviously effect on improving the heat transfer performance of syrup falling film evaporation, under the same experimental conditions, the total heat transfer coefficient improved 25.9%~82.9% than that inserted nothing, and the decline rate of total heat transfer coefficient with time was lower apparently. When the heat transfer temperature difference increased, the heat transfer of the evaporation side for inner tube get better but the condensation side for outer tube get deterioration, material physical properties changes (viscosity reduction) can enhanced heat transfer effect by increasing the heat transfer temperature difference. In the non-fouling affected heat transfer period, further processed was made for the evaporation side heat transfer coefficient, which obtaining the correlation between the inner tube comprehensive heat transfer coefficient and heat transfer temperature difference.

Characterization of Pressure Drop in Three-phase Filtration on Natural Gas Filters

Yitong HAO Zhongli JI Zhen LIU Yufeng LIU

Chin. J. Process Eng.. 2017, 17(6): 1140-1147. DOI: 10.12034/j.issn.1009-606X.217136

Asbtract ( )

PDF (1953KB) ( )

References | Related Articles | Metrics

The characterization of industrial filter was investigated by alternation of gas?solid, gas?liquid filtration and gas?liquid?solid filtration experiments. By observing the microstructure of the filter surface, the reason of the filter pressure drop change and the filtration mechanism were demonstrated. The results showed that under the same filtration conditions, during gas?liquid filtration using solid?containing filter, due to the interaction between the droplets and the filter cake layer, the structure of the filter surface changed. The filter pressure drop can be divided into four stages: gas?solid filtration, cake layer abscission, droplet filling and surface filtration. Gas?solid filtration of liquid-containing filter can be divided into two stages: initial filtration and dust filling. Although liquid holdup of filter was different, and the pressure drop of gas?solid filtration was similar. And the growth rate of pressure drop in three-phase filtration was between the solid filtration and the liquid filtration, therefore the droplet can effectively suppress the pressure drop growth.

Simulation on Blast Volume Distribution of Blast Furnace Tuyeres with Double Hot Blast Main Structure

Wenpeng LIU Yan JIN Xiaosen DONG

Chin. J. Process Eng.. 2017, 17(6): 1148-1155. DOI: 10.12034/j.issn.1009-606X.217149

Asbtract ( )

PDF (3837KB) ( )

References | Related Articles | Metrics

According to the requirement of blast furnace smelting, the distribution of blast volume was changed directly by using the tuyeres with different diameters or blocking one tuyere, which further improve the smelting environment. The numerical simulation method was used to study the blast volume distribution of the 3200 m3 blast furnace with double hot blast main structure of hot-blast system in a steel work, by establishing fluid dynamics model to simulate the flow field of the hot blast system from different aspects. The results showed that the asymmetry of blast volume distribution increased when blocking single or double tuyeres, but the volume difference between each tuyere decreased when plugging the two symmetrical tuyeres on the two sides of the entrance, the inhomogeneity was only 4.02%, less about 10% than non-blocking tuyere. When reducing diameter of single tuyere 10 mm, the distribution of blast volume was basically unchanged, and it had a significant effect only to reduced tuyere itself and the tuyere with the farthest distance from the entrance, and heterogeneity increased significantly. Reducing the diameter of one tuyere with the farthest distance from the entrance, lead the largest volume variation of 21.57% between each tuyere, which was about 4 times as normal condition.

Structural Optimization for Hopper of Bottom Inlet Bag Filter Based on Airflow Uniform Distribution

Meitao REN Yi WANG Honggang YANG Xiaoni YANG

Chin. J. Process Eng.. 2017, 17(6): 1156-1162. DOI: 10.12034/j.issn.1009-606X.217170

Asbtract ( )

PDF (1261KB) ( )

References | Related Articles | Metrics

The computational fluid dynamic simulation of the airflow inside a bag filter was carried out, three optimized structures of the hopper were proposed to improve the original hopper structure. The flow characteristics of the airflow inside the bag filter were obtained. The effect of airflow distribution of three optimized structures were compared with original structure. The results showed that the airflow in the hopper of the original structure formed an impinging jet. The maximum velocity was 8.3 m/s, and the minimum velocity was only 0.5 m/s, the relative root mean square velocity of the monitoring surface was 0.99. The velocity distribution on the corresponding monitoring surface was extremely uneven along the mainstream direction. The airflow uniformity inside the bag filter was improved in all three optimized structures, thus it was possible to improve the airflow uniform distribution by adding baffles. Considering the airflow uniform distribution inside the bag filter, adding vertical baffles was optimal, which can be improved by 41.41%. However the uniformity of the optimized structures with the third tilted baffle or the straight plate with a wing were not significantly improved compared to the addition of vertical baffles. Therefore when the hopper structure is optimized, the influence of the deflection of impinging jet on the airflow distribution inside the hopper can be neglected.

Discrete Modeling of Effect of Insert on Discharge Dynamics of Granular Material in Moving Bed

Qiang LIU Jinglin SU Jinhui ZHAN Guangwen XU Xiaoxing LIU

Chin. J. Process Eng.. 2017, 17(6): 1163-1169. DOI: 10.12034/j.issn.1009-606X.217171

Asbtract ( )

PDF (722KB) ( )

References | Related Articles | Metrics

To satisfy the design requirement that in coal pyrolysis moving bed reactor the flow structure should be in mass flow pattern, the influences of insert settings on the flow behavior of granular assembly in moving bed were investigated by conducting discrete element simulations with three types of insert with different geometrical structures were considered: disk-shape, triangle-shape and splayed-shape. The simulation results showed that for disk-shape and triangle-shape inserts, the flowing zone width was approximately equal to the sum of the flowing zone width of the moving bed without insert and the maximum projection size of insert in the flowing direction. As to the splayed-shape insert, depending on its vertical position and the distance between the two wings there existed three types of flow structure. The flowing zone width achieved the maximum value when the distance between the two wings was equal to the outlet size. For the investigated conditions, there existed optimal vertical position(~30d) and the distance of wings (~20d) (d was diameter of the largest particle) under which condition the flow rate is notably larger than that for moving bed without insert.

Copper Separation from Spent Lithium Ion Battery by Hydroxyoxime Extractants

Yan CHEN Jiehong CHENG

Chin. J. Process Eng.. 2017, 17(6): 1170-1175. DOI: 10.12034/j.issn.1009-606X.217125

Asbtract ( )

PDF (363KB) ( )

References | Related Articles | Metrics

To extract and separate copper from spent lithium ion battery leaching solution were carried out by using two domestically-made extractants of N902 and AD100. Effects of initial pH of aqueous phase, extractant concentration, phase ratio (O/A) and extraction time on copper extraction rate were investigated. The experiments were carried out at room temperature. The results showed that the first-stage copper extraction rate can achieved 98.3% for N902, under the optimal conditions of initial pH of 3.0, extractant concentration of 20%, phase ratio (O/A) 1:1 and extraction time 240 s. While the first-stage extraction rate can be 97.1% for AD100, under the conditions of initial pH 3.0, extractant concentration 25%, O/A 1:1 and extraction time 180 s. By using sulfuric acid as stripping agent, the first stage stripping rates of the copper for two extractants of N902 and AD100 can achieved both more than 95%, copper was recovered efficiently, and presented similar effect.

Complexation Extraction of 3-Hydroxypropionic Acid from Its Dilute Solution

Yifan ZHU Yingbo LI Xiangfeng LIANG Mo XIAN Huizhou LIU

Chin. J. Process Eng.. 2017, 17(6): 1176-1181. DOI: 10.12034/j.issn.1009-606X.217158

Asbtract ( )

PDF (450KB) ( )

References | Related Articles | Metrics

Tri-n-octylamine (TOA) was employed as extractant, and n-octanol, dichloromethane, ethyl acetate, methyl-iso-butyl ketone (MIBK), n-hexane and cyclohexane were used as diluents for the extraction of 3-hydroxypropionic acid (3-HP) from its dilute aqueous solution. The effects of diluents on extraction was explained. The influences of temperature, aqueous pH, phase ratio and volume fraction of TOA on the equilibrium distribution coefficient were investigated. The structure of organic phase loaded with 3-HP was studied by IR spectrometer and the mechanism of complexation extraction was explored and proposed. The results showed that n-octanol exhibited best extractability among the tested diluents, with a distribution coefficient of 4.46. Backward extraction was performed with sodium hydroxide aqueous solutions, and a backward extraction rate of 99.6% was obtained.

Separation of Vanadium(IV) from Iron(II) in Hydrochloric Acid Solution by Solvent Extraction with P507

Dan LI Desheng CHEN Guozhi ZHANG Hongxin ZHAO Tao QI Weijing WANG

Chin. J. Process Eng.. 2017, 17(6): 1182-1187. DOI: 10.12034/j.issn.1009-606X.217173

Asbtract ( )

PDF (439KB) ( )

References | Related Articles | Metrics

The separation of vanadium (IV) from iron (II) in hydrochloric acid leaching solution, which contained low concentration of vanadium (IV), high concentration of iron (II), and many kinds of impurities was investigated by solvent extraction with 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (P507). Under the optimal extraction conditions, i.e., initial pH of leaching solution of 0-0.6, extraction temperature of 30°C, extraction time of 15 min, P507 concentration(v/v) of 20%, and phase ratio (O/A) of 1:1, the extraction of vanadium (IV) and iron (II) was 70% and 5% in a single step. The sulfuric acid solution was used as the stripping agent. Under the optimal stripping conditions, i.e., stripping time of 12 min, stripping temperature of 30°C, phase ratio (O/A) of 4:1, and H2SO4 concentration of 368 g/L, nearly 100% of vanadium (IV) and 3% of iron (II) was stripped in a single step. Through one step extraction and stripping, a loaded stripping solution containing vanadium (IV) of 18.62 g/L and iron (II) of 0.37 g/L was obtained, showing a good separation of vanadium (IV) from iron (II). The results showed that vanadium (IV) could be also separated from other impurities such as aluminum, calcium, magnesium, and manganese.

Fabrication of Forward Osmosis Membranes with CNTs/PAN Fibers Supporting Layer

Wanxiao LONG Liangjie WANG Yuping LI Chunlei SU

Chin. J. Process Eng.. 2017, 17(6): 1188-1194. DOI: 10.12034/j.issn.1009-606X.217193

Asbtract ( )

PDF (2860KB) ( )

References | Related Articles | Metrics

A thin film forward osmosis (FO) composite membrane with a polyacrylonitrile/multi-walled carbon nanotubes (PAN/f-MWCNTs) substrate via electrospinning was fabricated, the effects of PAN concentration and f-MWCNTs on membrane morphology, hydrophilicity and FO performance were investigated. The results showed that increase of PAN concentration promoted the diameter of nanofiber and decreased water flux and reverse salt flux. The addition of f-MWCNTs improved both the hydrophilicity and mechanical strength. The contact angle of FO memebrane with PAN/f-MWCNTs substrate was 41.39°, much smaller than that of FO memebrane with pure PAN fiber substrate (61.86°), and its mechanical strengths was 10.55 MPa while that of pure PAN fiber substrate was 3.60 MPa. The prepared membrane exhibited a high water flux of 79.1 L/(m2?h) with 1.0 mol/L NaCl as the draw solution and deionized water as feed solution, which surpassed that of two commercial FO membranes [CTA-NW 8.8 L/(m2?h) and CTA-ES 18.4 L/(m2?h)] and reported thin-film composite FO membrane, and also had a low reverse salt flux of 50.4 g/(m2?h).

Selective Reduction and Enrichment of Nickel and Iron in Limonitic Laterite Ore with the Addition of Sodium Sulfate

Chao LU Jingcheng DONG Bo LI Shiwei ZHOU Hua WANG Yonggang WEI

Chin. J. Process Eng.. 2017, 17(6): 1195-1202. DOI: 10.12034/j.issn.1009-606X.217122

Asbtract ( )

PDF (1273KB) ( )

References | Related Articles | Metrics

The limonitic laterite ore containing 1.17% Ni and 35.71% Fe by the coal-based reduction?magnetic separation process was studied using sodium sulfate as additive. The results showed that nickel was mainly associated with oxides (27.40%) and silicates (69.35%) in ore. For a ferronickel content of 13.26% Ni and 67.34% Fe, nickel recovery rate of 88.40%, iron recovery rate of 14.71% could be obtained under the best conditions of reduction temperature 1100℃, reduction time 60 min, the mass fraction of additive 20% and reductant 8% by the application of a 200 mT magnetic field, the enrichment ratio of nickel reached 11.33. Addition of sodium sulfate destroys the silicate mineral structure, and the majority of nickel and iron is liberated from silicates, FeS could also be generated. The formation of FeS inhibits the reduction of iron, decreases the system melting point, intensifies the process of metal irons mass transfer and enhances ferronickel particles growth during the reduction of laterite.

Melting Temperature Test of Slag Rich in Rare Earth Oxides

Yongchun DENG Yinju JIANG Yongqiang WANG

Chin. J. Process Eng.. 2017, 17(6): 1203-1207. DOI: 10.12034/j.issn.1009-606X.217131

Asbtract ( )

PDF (451KB) ( )

References | Related Articles | Metrics

Processed by selective oxidation?reduction and melting separation, the rare earth oxides in the rare earth wastes such as rare earth NdFeB, hydrogen storage alloys, Ni?MH battery electrodes, etc. were enriched into molten slag. In order to get the needed slag which was rich in rare earth oxides and with suitable melting temperature, the hemispherical method was adopted to study the melting temperature. The results showed that the melting temperature of the REO?SiO2?Al2O3?FeO?B2O3 slag decreased as the content of REO decreased and the content of FeO increased, and the melting temperature of the REO?SiO2?Al2O3?MnO slag decreased with REO content reduced. Because of their high content of rare earth oxides and proper melting temperature, the 60%(Pr,Nd)Ox?19.3%SiO2?9.7%Al2O3?7%FeO?4%B2O3 slag and the 55%(La, Ce)Ox?25.3%SiO2?12.7%Al2O3?7%MnO slags were the best choices for the based slag for NdFeB and hydrogen storage alloys and Ni–MH battery electrodes to extract rare earth.

Development and Pilot Test of Surface-coating SCR Denitration Catalyst at Low Temperature

Hong ZENG Pingle LIU Yusheng ZHANG Changming LI Jian YU Guangwen XU Shiqiu GAO

Chin. J. Process Eng.. 2017, 17(6): 1208-1216. DOI: 10.12034/j.issn.1009-606X.217141

Asbtract ( )

PDF (1049KB) ( )

References | Related Articles | Metrics

The honeycomb deNOx catalyst was fabricated by coating the 4%V2O5?4%MoO3?5%WO3/TiO2 catalyst slurry on the cheap honeycomb substrate. The results showed that monolithic coating catalyst with thickness of 110 ?m showed nearly the same deNOx activity as the conventional extruded honeycomb catalyst. However, the usage of expensive active components only accounted for 12.8% raw material needed for the extruded catalyst, which significantly decreased the catalyst costs. The catalyst showed extraordinary SO2/H2O-resistant stability at 250℃ during the 100 h discontinuous test with excellent intensity and wearability. The pilot test of the coating catalyst over the flue gas from glass kiln exhibited excellent deNOx performance with above 80% NO conversion rate and less than 3?10?6(?) NH3 escape during the 1100 h stable test under the conditions of 2800 mg/Nm3 inlet NOx concentration, 240?300℃ and 7150 h?1 GHSV.

Filtration and Dewatering Characteristics of Nesquehonite Suspensions: Experimental and Modeling

Daoguang WANG Zhibao LI Yingjun WANG

Chin. J. Process Eng.. 2017, 17(6): 1217-1226. DOI: 10.12034/j.issn.1009-606X.217142

Asbtract ( )

PDF (1184KB) ( )

References | Related Articles | Metrics

The effect of particle characteristics (i.e. particle size and shape), as well as operating conditions (i.e. pressure drop, ionic strength, solid concentration in slurry and filtration temperature) on the settling, filtration and dewatering properties of nesquehonite were investigated. The results showed that the settling rate was strongly dependent on ionic strength and solid concentration. Meanwhile, the filterability, independent of ionic strength, was improved under the conditions of high solid concentration and filtration temperature, low vacuum pressure drop and large crystal size of nesquehonite. Increased dewaterability was revealed at high vacuum pressure drop and solid concentration. Besides, compressibility coefficient and pore size distribution index of nesquehonite cake were determined by further modeling work. Finally, Happel model was used to predict the specific cake resistance with the particle size, average cake porosity and other particle characteristic data of nesquehonite, and the calculated values were in good agreement with experimental data.

Regeneration and Cyclic Utilization of Iron-based Desulfurization Residue

Pengju HU Zhihong PENG Qiusheng ZHOU Tiangui QI Guihua LIU Xiaobin LI

Chin. J. Process Eng.. 2017, 17(6): 1227-1232. DOI: 10.12034/j.issn.1009-606X.217157

Asbtract ( )

PDF (459KB) ( )

References | Related Articles | Metrics

The regeneration and cyclic desulfurizing of iron-based desulfurization residue by oxidation was studied. The results indicated that sulfur removal rate of the residue and cyclic desulfurization rate of the regenerative desulfurizer were 97.70% and 40.90% respectively, after the desulfurization residue was oxidized at 50℃ with 1 times theoretical dosage of hydrogen peroxide and 50 g/L NaOH. While, the sulfur removal rate and the cyclic desulfurization rate were correspondingly 83.71% and 52.74%, by aerating oxygen at 1.2 L/min and oxidizing the residue at 70℃ for 110 min with 50 g/L NaOH. When the residue was oxidized in alkaline system, sulfur species of the residue mainly converted to S2O32? in liquid phase and the iron species could transform into FeOOH in solid phase.

Isothermal Drying Kinetics of Paddy Based on Thermogravimetric Analysis

Jing ZHANG Peiyong MA Xianjun XING Yongqiang XING Yongling LI Jinzhou WU

Chin. J. Process Eng.. 2017, 17(6): 1233-1238. DOI: 10.12034/j.issn.1009-606X.217160

Asbtract ( )

PDF (539KB) ( )

References | Related Articles | Metrics

The isothermal drying kinetics of 21.05% dry basis moisture content paddy was studied by thermogravimetric analysis at experimental temperature of 40, 50, 60 and 70℃. The results indicated that the final moisture content of the sample gradually decreased with the drying temperature increasing, the drying rate and the drying rate peak became higher. The five drying models were utilized to fit the different experimental data. The results showed good fitting effect with all models’ R2 (correlation coefficients) more than 0.9653. The Midilli?Kucuk model’s R2 even more significant than others, due to its value larger than 0.9994, which indicated that the Midilli?Kucuk model was the most appropriate model for this experiment. The effective moisture diffusion coefficient would increase with the drying temperature increasing, and the calculated activation energy was 5.23 kJ/mol.

Alkylation of Alkylphenol, Alkoxyphenol and Their Mixture with Methanol under the Catalysis of Alkali and Alkaline-earth Salts Modified Activated Alumina

Shaohua ZHANG Ze WANG Weigang LIN Wenli SONG Songgeng LI

Chin. J. Process Eng.. 2017, 17(6): 1239-1248. DOI: 10.12034/j.issn.1009-606X.217162

Asbtract ( )

PDF (392KB) ( )

References | Related Articles | Metrics

Using methanol as the alkylation reagent, the alkylations of alkylphenol, alkoxyphenol, and their binary and five-component mixtures were investigated, under the catalysis of alkali (A) and alkaline-earth (AE) salts modified activated alumina (AA). The results showed that phenol and methylphenol can high efficiently be converted to O-alkylation products over A/AA. Specifically, under the catalysis of Cs2CO3/AA, the conversion rate of phenol reached to the highest value of 90.4%(?) with high anisole selectivity of 96.1%(area). However, under the same reaction conditions, neither the conversion rate nor the product selectivity is satisfactory for the alkylation of methoxyphenol, and the adjustment of the reaction temperature, the space velocity, or the Cs loading amount cannot make the results better. There exists a strong synergistic effect for the co-alkylation of the alkylphenol/alkoxyphenol mixture, under this effect, the conversion of alkylphenol is inhibited, while the conversion of alkoxyphenol is promoted, with remarkably enhanced selectivity to C-alkylation products.

Preparation of V₂O₅-WO₃-TiO₂/Cordierite Based Catalytic Filter for Removal of NOx from Flue Gas

Yusheng ZHANG Changming LI Hong ZENG Chao YU Jian YU Yunquan YANG Guangwen XU Shiqiu GAO

Chin. J. Process Eng.. 2017, 17(6): 1249-1256. DOI: 10.12034/j.issn.1009-606X.217172

Asbtract ( )

PDF (5724KB) ( )

References | Related Articles | Metrics

After optimization of preparation methods and catalyst slurry recipes, the correlation among the solid content of slurries, catalyst loading and catalytic performance were researched. The results showed that the catalytic filter with 4.2%(?) catalyst loading was obtained by being immersed a practical cordierite ceramic filter into the 10% (?, TiO2) aqueous catalyst slurry under vacuum condition, followed by drying and calcination process. The slurry was composed of metatitanic acid, ammonium metavanadate and ammonium metatungstate with mass ratios of V2O5/TiO2=0.1 and WO3/TiO2=0.08. The resulting catalytic filter was evaluated for NH3-SCR reaction at filtration velocity of 1 cm/s and NH3/NO=1(?) at standard conditons. It exhibited that the NO conversion rate was beyond 90%, N2O escape is less than 25?10?6(?) and pressure drop was lower than 650 Pa at the temperature of 250?350℃. The catalytic filter also showed a excellent performance for resistance to steam and SO2 poisoning, which meets well the request of industrial application.

Preparation of Uniform-sized PLGA Microspheres Based on Novel Membrane Emulsification

Pei ZHAO Yan LI Jianmei WANG Xueying WANG Min XU Liqiu WANG

Chin. J. Process Eng.. 2017, 17(6): 1257-1264. DOI: 10.12034/j.issn.1009-606X.217180

Asbtract ( )

PDF (4089KB) ( )

Related Articles | Metrics

A novel pressure control method (constant-flow pump) was introduced to conventional membrane emulsification, for precisely controlling the transmembrane pressure of the dispersed phase, named novel membrane emulsification. Poly(lactic-co-glycolic acid) (PLGA) microspheres was prepared by oil-in-water emulsion method respectively, based on conventional membrane emulsification and novel membrane emulsification. Compared with conventional membrane emulsification, this novel membrane emulsification could remarkably improve the size distribution of PLGA microspheres. The processing conditions, stirring rate, the stabilizer concentration, the PLGA concentration and the dispersed phase flow rate, were optimized to fabricate PLGA microspheres with controllable sizes and narrow size distribution. The results showed that uniform-sized PLGA microspheres (size distribution coefficient Rspan<0.50) were successfully fabricated using 2 ?m microporous membraneunder the conditions of stirring speed about 300 r/min, the stabilizer concentration of 1.0%(?), the PLGA concentration of 60 mg/mL and the dispersed phase flow rate of 20 mL/h. The relative standard deviation was 1.99%, and the product repeatability was good.

Acetalization of 1,2,4-Butanetriol with Aldehydes in Dilute Aqueous Solutions: Thermodynamic and Kinetic Characteristic

Min LI Yingbo LI Haiyan LUO Mo XIAN Xiangfeng LIANG Huizhou LIU

Chin. J. Process Eng.. 2017, 17(6): 1265-1273. DOI: 10.12034/j.issn.1009-606X.217202

Asbtract ( )

PDF (507KB) ( )

References | Related Articles | Metrics

The acetalization reaction between 1,2,4-butanetriol and aldehydes (butyaldehyde, valeraldehyde and hexaldehyde) to produce butanetriol acetals (AC) was investigated with different catalyst amounts, molar ratios and temperatures. Through the study of the reaction thermodynamic equilibrium, the value of the equilibrium constant as a function of temperature and the corresponding thermodynamic parameters ?rH0298K, ?rS0298K, and ?rG0298K were obtained. The results showed that the reaction in the temperature range of 298?323 K was exothermic and significantly thermodynamic limitations. A simple kinetic model well describing the reaction process was presented. The activation energy of the overall acetalization reaction was 51.1?52.3 kJ/mol. Furthermore, the effect of alkyl of various aldehydes on acetalization was quantitatively analyzed using LFER and it demonstrated that excellent correlation between reaction equilibrium and rate constants and polar effect parameter (?*) was found.

Synthesis and Electrocatalytic Performance of the Carbon-supported ORR Catalyst from Pork Liver

Tuanyu GUO Dandan YANG Ruowen LIANG Wenmu LI Guiyang YAN

Chin. J. Process Eng.. 2017, 17(6): 1274-1280. DOI: 10.12034/j.issn.1009-606X.217257

Asbtract ( )

PDF (750KB) ( )

Related Articles | Metrics

The non-precious metal catalyst was prepared by two-step pyrolysis method and carbon-supported method from the very cheap biomass, pork liver, as the raw material. The influences of the heat-treatment temperature, the ratio of mixed gase and precursor on the catalytic activity were investigated. The results showed that the catalyst, which was prepared at 1000℃ and the volume ratio of N2:NH3 was 7:3, exhibited remarkably excellent electrocatalytic performance for the oxygen reduction reaction (ORR). The two-step pyrolysis under NH3 has changed the surface morphology and crystal phase structure of the as-prepared catalyst, which assisted to obtain the high percentage of pyridinic-N. It has enhanced the electrocatalytic performance for the oxygen reduction reaction in the alkaline environment. Alought Black Pearls 2000 (BP2000) could improved the performance of one-step pyrolysis catalyst, its reactivity under NH3 was not good as that of carbon-supported from pork liver, causing an adverse impact on the performance of two-step pyrolysis catalyst.

Effects of Organic Media Treatment Saccharomyces cerevisiae on Its Catalytic Performance to Asymmetric Reduction Reaction

Feng LI Shiyin FANG Xianai SHI

Chin. J. Process Eng.. 2017, 17(6): 1281-1286. DOI: 10.12034/j.issn.1009-606X.217217

Asbtract ( )

PDF (452KB) ( )

References | Related Articles | Metrics

Different organic media were used to induce changes of cell membrane properties, i.e. the membrane permeability, mobility and integrity. The effect of organic media treatment on the asymmetric reduction of 2-octanone catalyzed by Saccharomyces cerevisiae cells was investigated. The results showed that the reaction yield was significantly decreased when the leakage values of nucleic acid and protein reached 0.057 and 0.046 respectively, or the propidium iodide (PI) uptake factor reached 1.157. When the anisotropy value of cell membrane labeled with diphenylhexatriene (DPH) reached 111.7% of the control group, the cells lost the ability of catalyzing asymmetric reduction. When the ratio of cell with damaged membrane integrity reached 41.8%, the reaction yield was significantly reduced. In the premise of maintaining the integrity of cell membrane, cell membrane permeability and mobility in the appropriate range make Saccharomyces cerevisiae cells show good performance on catalyzing 2-octanone asymmetric reduction reaction.

Synthesis and Characterization of MnCo2O4 Magnetic Nanocrystals

Yanping LI Dongwei YAN Shaoxiong ZHOU

Chin. J. Process Eng.. 2017, 17(6): 1287-1290. DOI: 10.12034/j.issn.1009-606X.217155

Asbtract ( )

PDF (1055KB) ( )

References | Related Articles | Metrics

MnCo2O4 magnetic nanocrystals was synthesized by one-step method used potassium permanganate (KMnO4), manganese acetate [Mn(Ac)2] and cobalt acetate [Co(Ac)2] as raw materials. The morphology, structure, composition and magnetic property of MnCo2O4 crystals were studied. The results showed that MnCo2O4 magnetic nanocrystals had a narrow size distribution of 80?120 nm and display perfect sheet shape with high crystallinity and good dispersity. MnCo2O4 nanocrystals exhibit good magnetic property with a high Curie temperature of 182 K.

Effect of Cr Modification on the Solidification Structure and Effective Nucleation of Metal Manganese

Weitao QIAN Zhi WANG Guoyu QIAN Keqiang XIE Liyuan SUN Wenhui MA

Chin. J. Process Eng.. 2017, 17(6): 1291-1298. DOI: 10.12034/j.issn.1009-606X.217164

Asbtract ( )

PDF (1085KB) ( )

References | Related Articles | Metrics

ICP-OES, DSC?TGA and metallographic microscope were used to study the effect of Cr addition on the solidification structure of metal manganese. The results showed that the solidification structure of metal manganese was mainly columnar dendrite after metamorphic treatment. However, the addition of Cr was beneficial to the refinement of dendritic structure. When the addition of Cr increased from 0 to 3.7%(?), the average grain size was first decreased and then increased. When the addition of Cr was 0, the average grain size of metal manganese was 69.0 ?m. However, with the addition of Cr increased to 2.0%(?), the average grain size reached the minimun, and it was only 37.5 ?m. Further increasing the addition of Cr to 3.7%(?), the average grain size would increase to 51.8 ?m. The increase of number of effective heterogeneous nuclei in melt was the main reason for solidification structure refinement of metal manganese.

Preparation of Environmentally Friendly Styrene Butadiene Rubber with Modified Steel Slag Instead of Carbon Black and Their Properties

Hao ZHANG Gang YANG Hongming LONG Gang TANG Xiuyu LIU

Chin. J. Process Eng.. 2017, 17(6): 1299-1303. DOI: 10.12034/j.issn.1009-606X.217165

Asbtract ( )

PDF (1190KB) ( )

Related Articles | Metrics

Phosphoric acid and steel slag were used to prepare modified steel slag, then, environmentally friendly styrene butadiene rubber were prepared by synthesizing styrene butadiene and carbon black partially substituted by modified steel slag. The effects of ratios of phosphoric acid/steel slag, modified steel slag/carbon black and accelerator/sulfur on the mechanical properties of prepared samples were studied, respectively. The results showed that when the mass ratio of phosphoric acid/steel slag was 10:250, modified steel slag showed the optimal pore structure, the specific surface area, pore volume and average pore diameter were 15.093 m2/g, 0.0868 mL/g and 24.87 nm accordingly. With the mass ratios of modified steel slag/carbon black and accelerator/sulfur as 260:250 and 10:15, the prepared sample presents the best comprehensive performance in terms of mechanics and economy, tensile strength 23.7 MPa, Shore A hardness 67.9 and tear strength 41.2 kN/m.

Preparation and Performance of Modified Steel Slag-based Phase Change Powders

Hao ZHANG Gang YANG Hongming LONG

Chin. J. Process Eng.. 2017, 17(6): 1304-1309. DOI: 10.12034/j.issn.1009-606X.217181

Asbtract ( )

PDF (1066KB) ( )

Related Articles | Metrics

Modified steel slag-based phase change powders with modified steel slag shell and paraffin core were synthesized by vacuum adsorption. The pore structure, material composition, phase change temperature and phase change enthalpy, particle size distribution, surface morphology of modified steel slag-based phase change powder were characterized. And concrete of modified steel slag-based phase change powders with modified steel slag-based phase change powders were synthesized, the flow performance, cohesive performance and water resistance, mechanical properties, hydration heat performance were analyzing. The results showed that phosphate amount, paraffin amount and pressure in drying oven had great effects on the paraffin intake of modified powders. When phosphate amount 6%(?), paraffin amount 30%(?) and pressure in drying oven 0.04 MPa, modified steel slag-based phase change powder had good phase change energy storage performances, such as phase change temperature 53.7℃ and phase change enthalpy 12.20 J/g. Concrete of modified steel slag-based phase change powders not only had good flow performance, cohesive performance and water resistance, as well as mechanical properties of high early strength and post strength stability, but also had the characteristics of reduce the concrete temperature peak and hysteresis temperature peak to peak.

Effect of Dissolution Systems on Properties of Cellulose-based Aerogels

Yuqing ZHANG Yifan LIU Guifang YANG Jiachen LU Minghua LIU

Chin. J. Process Eng.. 2017, 17(6): 1310-1315. DOI: 10.12034/j.issn.1009-606X.217188

Asbtract ( )

PDF (1860KB) ( )

References | Related Articles | Metrics

In order to study the properties of cellulose-based aerogels obtained from different dissolution systems, cotton cellulose was dissolved in four kinds of dissolving system including NaOH/urea/H2O, NaOH/thiourea/H2O, ionic liquids 1-butyl-3-methylimidazolium chloride (BMIMCl) and 1-allyl-3-methylimidazolium chloride salt (AMIMCl). Additionally, the obtained cellulose-based aerogels were characterized, and the adsorption performance to chlorate ions (ClO3?) were studied. The results showed that the crystal structures of cellulose-based aerogels transforms from type I into II. The aerogels obtained from BMIMCl solvent system gives lower crystallinity a thermal stability than those from the other solvent systems, whereas it possesses higher specific surface area, total pore volume and smaller average pore size, and higher adsorption performance for trace amount of ClO3? in aqueous solution.

Reaction Characteristics of Intermediate Product during Oil Shale Pyrolysis

Mengya LI Jinhui ZHAN Yong TIAN Dengguo LAI Xiaoxing LIU Guangwen XU

Chin. J. Process Eng.. 2017, 17(6): 1316-1321. DOI: 10.12034/j.issn.1009-606X.217150

Asbtract ( )

PDF (548KB) ( )

References | Related Articles | Metrics

The pyrolysis experiments of oil shale were performed under different ending temperatures, and the pyrolysis intermediate pyrolysis bitumen were obtained by the solution extraction of semicoke. The component analysis of shale oil and pyrolysis intermediate was implemented by gas chromatography?mass spectrometry characterization method. Furthermore, pyrolysis?gas chromatography?mass spectrometry method was used to analyze the distribution of intermediate decomposition products with comparison of pyrolysis of shale oil. The results showed that the intermediate can be produced and stably exist at a limited temperature range of 350~400℃, yield of intermediate reaches the highest value at the temperature of 375℃. The stage of the highest rate for oil-producing occurred at temperature range of 375~400℃, while yield of pyrolysis intermediate started to decrease. Actually pyrolysis intermediate was thermally unstable during the high temperature. The kerogen cracked to form bitumen intermediate and then transformed to final pyrolysis products immediately. The relative content of light components in intermediate increased with rising temperature. Heteroatom-containing compounds can be first released from kerogen and convert into intermediate products. The generation of alkenes in shale oil may be derived from the decomposition of kerogen without experiencing intermediate stage. The long side chains of aromatic hydrocarbons in intermediate can become short by decomposition.

Effect of CaCO3 on Gasification Reactivity of Anthracite Char

Shaolong WANG Pengfei ZHANG Songhua ZHOU Yan XIE Yang CAO Xianquan AO

Chin. J. Process Eng.. 2017, 17(6): 1322-1328. DOI: 10.12034/j.issn.1009-606X.217182

Asbtract ( )

PDF (1140KB) ( )

References | Related Articles | Metrics

The influence of CaCO3 on Guizhou anthracite char?CO2 gasification reactivity was studied. The effects of CaCO3 coking method, gasification temperature and addition amount on the gasification reactivity were investigated in a fixed-bed reactor at atmospheric pressure. The calcium forms existing during the coal pyrolysis or char gasification, functional groups of coal char and the surface morphology of coal char were characterize. The results showed that the gasification activity of coke obtained by loading CaCO3 after pyrolysis is higher than that by loading CaCO3 before pyrolysis. The gasification activity increased with the increase of CaCO3 addition, but when the addition amount was more than 3.5%(?), the gasification activity changed little. In the process of pyrolysis and char gasification, CaCO3 will react with other substances in coal and convert to CaS and CaAl2Si2O8.

Table of Content