Asia-Pacific Journal of Chemical Engineering
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2017
·Vol. 12
·期 4
·527-535
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IF 0.836
Guizhuan Xu,Binglin Chen,Zhangbin Zheng,Kai Li,Hongge Tao
5-Ethoxymethylfurfural (EMF) and ethyl levulinate (EL) have been considered as the new promising biofuels. A comparative study was conducted for the direct conversion of carbohydrates into EMF and EL in different medium containing ethanol. The distribution and formation kinetics of EL, EMF, 5-hydroxymethylfurfural (HMF) and levulinic acid (LA) in pure ethanol and ethanol/organic solvent medium were compared, and the results showed that the addition of n-hexane can improve the accumulation of EMF. When the volume ratio of ethanol to n-hexane was 6:4, 66.29% of EMF yield can be obtained from fructose at 120°C and 180 min. The total yield of the EMF and EL can reach to 83.71%, increased by 5.73% compared with that in pure ethanol medium. Moreover, water addition can suppress the etherification of HMF to EMF and promote the rehydration of HMF to LA in the process. On the basis, a putative reaction pathway for the conversion of carbohydrates in ethanol/n-hexane medium was proposed. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
化学工程
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可再生能源
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2013
·Vol. 9
·期 2
·248-255
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IF 0.797
Jianxian Zeng,Qiannan Guo,Zhenzhong Ou-Yang,Hu Zhou,Huajun Chen
Polyelectrolyte-enhanced ultrafiltration was investigated for the removal of chromium(VI) anion from aqueous solutions with the help of cationic polyquaternium-6 (PQ6). The ultrafiltration behavior of Cr(VI) aqueous solutions was studied at pH 6. Owing to an effect of electrostatic repulsion, the membrane with a molecular weight cutoff (MWCO) of 10 000 Da rejected about 30% of Cr(VI). Then, ultrafiltration of aqueous solutions of a Cr(VI)–PQ6 complex was further studied. Factors affecting Cr(VI) rejection coefficient ( R Cr ) and permeate flux ( J ) such as pH, polymer metal ratio (PMR), the added salts, temperature, operating pressure and MWCO were investigated. The best operating parameters, such as pH 9 and PMR 10, were obtained in order to achieve high R Cr (>0.97). By increasing the concentrations of the added salts (KCl, KNO 3 and K 2 SO 4 ), R Cr was found to decrease significantly. J decreases slightly in the pH range of 2–5. Cl − or SO 4 2− does not affect J , whereas NO 3 − results in the decrease of J . The binding mechanisms of dichromate, chromate and nitrate with PQ6 were proposed. Finally, the concentration experiment was carried out under the optimal conditions. R Cr was close to 1, and J decreases slightly. Chromium was effectively concentrated by the membrane. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
环境科学
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化学工程
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2014
·Vol. 9
·期 5
·686-695
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IF 0.623
Peng Peng Zhang,Dong Shen Tong,Chun Xiang Lin,Hui Min Yang,Zhe Ke Zhong,Wei Hua Yu,Hao Wang,Chun Hui Zhou
The production of nanocellulose with controlled structure from plant sources with easy availability and good sustainability is very important in science and engineering. In this work, the isolation of cellulose from bamboo and the effects of the hydrolysis of different acids on the morphology, structure, and properties of the resultant cellulose and cellulose nanocrystals were investigated. Bamboo cellulose (PHC) was first isolated from raw bamboo powder by alkali and consecutive bleaching treatments. Cellulose crystallites were then prepared by the controlled hydrolysis of PHC in acid solutions. The samples were characterized by using thermogravimetric analysis, Fourier transform infrared spectroscopy, powder X-ray diffraction, laser particle size analyzer, Scanning electron microscopy, and Transmission electron microscopy. Cellulose nanocrystals prepared from the hydrolysis of the isolated bamboo cellulose in the sulfate acid, hydrochloric acid, phosphoric acid, or acetic acid solution had the length of 3–200 nm, 20–85 nm, 20–40 nm, and 6.5–20 nm, respectively. Nanocrystals made by the uses of sulfuric acid and phosphoric acid possessed higher crystallinity and lower thermal stability than those by the uses of hydrochloric acid and a mixture of acetic acid and nitric acid. Results suggested the type of acids significantly influenced the structure, morphology, and thermal stability of cellulose crystallites. The anions in the acid solution also contributed to those differences because they affected the swelling of cellulose chains and breakage of hydrogen bonds in cellulose. The findings indicate that a judicious choice of pretreatment of the cellulose and its moieties can be used for the production of different cellulose nanocrystals. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
材料科学
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化学工程
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植物学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2017
·Vol. 13
·期 1
·e2156
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IF 0.836
Zhengjiang Liu,Huiyan Ma,Juming Liu,Lei Xing,Lin Cheng,Jucai Yang,Baodong Mao,Qiancheng Zhang
In this work, Hangjin2 # clay (HC), a natural iron-contained clay mineral first discovered in Inner Mongolia of China, is found to be able to catalyze the heterogeneous Fenton reaction efficiently upon rational modification. After activation using dilute sulfuric acid, the HC prohibited a significantly enhanced activity for heterogeneous Fenton reaction. Via acid activation process, Fe 2+ /Fe 3+ redox can be introduced on the surface of sulfuric acid-activated Hangjin2 # clay (SHC), and Brønsted acid sites can be also created on the surface of SHC. Furthermore, Brønsted acid sites could effectively promote the generation of •OH for methyl orange (MO) oxidation and facilitate the Fe 3+ /Fe 2+ redox process. Fenton degradation of MO was used to evaluate the effect of acid activation on the catalytic activities of SHC. Experimental results revealed that the high activity of SHC was mainly attributed to the synergetic effect of the abundant acid sites on catalyst surface and the Fe 3+ /Fe 2+ redox process. In addition, quenching studies confirmed that •OH radicals were principally responsible for the degradation of MO. More importantly, MO degradation for 3 consecutive cycles demonstrated SHC exhibited reusable and stable activity.
研究领域:
环境科学
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材料科学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2017
·Vol. 13
·期 1
·e2153
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IF 0.836
Zhuqian Xiao,Yidan Xu,Yu Fan,Qiang Zhang,Jianwei Mao,Jianbing Ji
Here, we developed a new strategy for preparation of series of in-situ reduction bimetallic catalysts Ni-W/SiO 2 by introducing of reducing agent in the preparation process. And these catalysts were applied into the catalytic hydrogenolysis of microcrystalline cellulose and pretreated lignocellulose. The results show that the in situ reduction 15%Ni–20%W/SiO 2 shows the prominent activity for microcrystalline cellulose conversion into ethylene glycol (EG), 1,2-propylene glycol, and glycerol with the highest yield of EG at 61.30% under the experimental condition. And the relative high of EG yield (30.23%) was obtained when a combinative pretreatment technology of steam explosion (0.45 MPa) coupled with hot alkali (70 °C) was introduced to enhance the hydrogenolysis of plant lignocellulose-based feedstocks over the in situ reduction catalyst 15%Ni–20%W/SiO 2 . The SEM and thermogravimetry analysis revealed that segmental lignin and hemicellulose were removed partly by hot alkali pretreatment. Meanwhile, the existence of Ni–W alloys and metal Ni particles were evidenced by X-ray diffraction spectra. In addition, by the detailed analysis via transmission electron microscopy and X-ray photoelectron spectroscopy, the catalytic particle size was distributed in the range of 9.3 ± 1.3 nm.
研究领域:
催化化学
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可再生资源转化
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2016
·Vol. 11
·期 2
·305-313
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IF 0.728
Xing Li,Lei Bei,Zhi Sun,Kun Liu,Xu Zhang,Xiaozhao Han
The study aimed at investigating the addition effects of P, K, and micronutrient fertilizers on the permeability of N-nutrient fertilizer urea through a representative polymer membrane, which is of great importance in polymer-coated compound fertilizer. Specifically, the permeability of urea through polystyrene membrane was determined experimentally at the nominal temperature of 298 K using the Ussing chamber method for fertilizer solutions of urea–water, urea–NaH 2 PO 4 –water, urea–Ca(H 2 PO 4 ) 2 –water, urea–KCl–water, and urea–NaCl–water. The experimental data showed that the addition effects of NaH 2 PO 4 , KCl, and NaCl on urea permeability were pronounced and could be promotion or suppression depending on the amounts added. The variation of urea permeability with additive concentration could be explained by the ‘solution–diffusion’ model, suggesting that the specific intermolecular and interionic interactions in the permeation solution were an important factor determining the permeability. Using the saturated urea–water solution as basis, the addition of saturated KCl increased the urea permeability by 2.5 times, while the addition of saturated Ca(H 2 PO 4 ) 2 and NaH 2 PO 4 decreased the permeability by 41% and 76%, respectively. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
农业科学
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材料科学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2022
·Vol. 17
·期 2
·e2754
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IF 1.777
Hao Zhou,Laiquan Lv,Mengting Ji,Yize Zhang,Fangzheng Cheng,Kefa Cen
Erythritol has attracted wide attention due to high latent heat of 297.2 kJ/kg and excellent chemical stability as a medium- to low-temperature thermal energy storage (TES) material. However, low thermal conductivity leads to extended charging and discharging time and severely affects its large-scale application. In this article, three cheap nanoparticles (CuO, Al 2 O 3 , and Fe 2 O 3 ) and triethanolamine (TEA) were used as heat transfer enhancers and dispersant to improve the TES performance of erythritol. Sedimentation of nanoparticles in erythritol indicates that TEA is an effective dispersant in erythritol for three kinds of nanoparticles. The experimental results show that the thermal conductivity increased from 0.671 W/(m·K) of erythritol to 0.722 W/(m·K) and 0.761 W/(m·K) of 1.5 wt% CuO and Fe 2 O 3 nano-enhanced phase change materials (NePCMs), respectively. Based on the DSC results, the melting temperature and heat of fusion of NePCMs stayed stable with nanoparticles but increased significantly after adding TEA. Furthermore, the charging/discharging cyclic behaviors of NePCMs were tested in the cycle test platform. During the cycle test, the melting time of 1.5 wt% CuO NePCM decreased from 657.9 s for pure erythritol to 615.8 s but increased to 757 s and 680.6 s for 1.5 wt% Al 2 O 3 and 1.5 wt% Fe 2 O 3 NePCMs. The solidification time decreased from 311.2 s for erythritol to 179.3 s, 198.5 s, and 132.4 s for 1.5 wt% CuO, 1.5 wt% Al 2 O 3 , and 1.5 wt% Fe 2 O 3 NePCMs. Interestingly, the supercooling degree of NePCMs we got from the test was much lower than that from the DSC curves, indicating that the supercooling is related to the sample size. These results testify that CuO and Fe 2 O 3 nanoparticles can improve the thermal conductivity of erythritol effectively.
研究领域:
材料科学
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能源工程
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2022
·Vol. 17
·期 4
·e2779
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IF 1.777
Dongxue Chu,Xiaoshu Qu,Shangfei Zhang,Jianrong Zhang,Zefeng Liu,Lili Zhou,Yanyan Yang
Polyoxometalates (POMs) are considered as an attractive option for electrochromic energy storage (EES) system due to their unique electrochemical feature. Herein, a composite film NW/P 2 W 17 /Cu (phen) 2 based on Dawson-type monolacunary POMs K 10 P 2 W 17 O 61 (abbreviated as P 2 W 17 ) and copper complex [Cu II (phen) 2 ](NO 3 ) 2 (abbreviated as Cu (phen) 2 ) formed on TiO 2 nanowire (abbreviated as NW) array substrate was fabricated by hydrothermal process and layer-by-layer self-assembly combination method. This rational designed film NW/P 2 W 17 /Cu (phen) 2 exhibits excellent tunable multicolor electrochromic behavior and improved pseudocapacitive performance with large optical modulation (43.7% at 600 nm), fast switching time (t c = 2.9 s, t b = 9.5 s), and high volumetric capacitance (228.0 F cm −3 at 0.3 mA cm −2 ). In the process of charge and discharge, the composite film can realize the transformation from light green to orange, green, and finally to blue-green color, successfully achieve the bridge between electrochromic behavior and energy storage, and monitor the level of stored energy by color change. This work showed great potential of POMs-based electrode materials for integrated electrochromism and energy storage applications.
研究领域:
材料科学
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电化学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2022
·Vol. 18
·期 1
·e2840
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IF 1.777
Qiaolin Ren,Ruirui Yang,Junying Li,Wenjun Yan,Zhongde Wang,Ailian Wu
Electrocatalytic oxidation technology has been proved as an efficient method for degradation in organic wastewater. The service lifetime and degradation efficiency of the electrode, one crucial struggle, limits the broad application of electrocatalytic oxidation technology. Herein, a Ru/Ir doped TiO 2 electrode with a long service lifetime was developed. Accelerated life experiment showed that the service life of an electrode was 33 h when the concentration of sulfuric acid was 1 M and the current density was 2000 mA·cm −2 . The influence on the phenol degradation was evaluated by researching the operating parameters. In particular, the possible mechanism of phenol removal at different pH is elucidated. It is found that acidic environment is favorable for chemical oxygen demand (COD) and phenol removal at a current density of 20 mA·cm −2 , pH 3 at 800 ppm NaCl, which can make the removal rates of phenol and COD with Ru/Ir doped TiO 2 anode up to 97.21% and 100%. In addition, it was demonstrated that the hydroxyl radicals play a foremost role in the degradation of phenol. Given the well stability and high service life, the Ru/Ir doped TiO 2 electrode holds promise for further industrial application in wastewater treatment.
研究领域:
环境科学
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电化学工程
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2022
·Vol. 18
·期 2
·e2871
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IF 1.777
Biao Jin,Shanshan Liu,Dongri Jin
The design of electrode materials for sensitive electrochemical sensors is important for the rapid detection of ascorbic acid. Using Physalis alkekengi L. husks (PaLH) as the carbon precursor, PaLH-derived carbon materials (PCM) were prepared by high temperature carbonization, and hierarchical porous carbon materials (KPCM) were prepared by KOH activation. The carbon materials were characterized by scanning electron microscopy, X-ray diffraction, and isothermal nitrogen adsorption and desorption. KPCM had a larger specific surface area (1345.45 m 2 g −1 ) and more micro/mesopores than PCM without KOH activation. Two types of carbon materials, PCM and KPCM, were used as electrode modifiers, and the electrochemical properties of KPCM/GCE and PCM/GCE (GCE = glassy carbon electrode) were investigated. KPCM/GCE had a higher electron-transfer rate, higher electrochemically active area, smaller charge-transfer resistance, wider potential window, and higher catalytic activity for ascorbic acid detection. An ascorbic acid electrochemical sensing platform constructed with KPCM/GCE showed high sensitivity (334.03 μA mM −1 cm −2 and 134.52 μA mM −1 cm −2 ) and a low detection limit (0.92 μM) ( S/N = 3) in the linear range of 0.005–1.6 mM. This method was applied to the analysis and determination of ascorbic acid in chewable vitamin C tablets.
研究领域:
分析化学
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材料科学
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电化学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2022
·Vol. 18
·期 1
·e2842
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IF 1.777
Jian Ruan,Youkai Jiang,Yaheng Zhang,Luhaibo Zhao,Jie Zhang,Zhiyong Tang
Microbubbles were applied for the first time to enhance the aqueous biphasic hydroformylation of long-chain alkenes. The gas–liquid–liquid multiphase hydroformylation was carried out using 1-dodecene as model higher olefin and dihexadecyl dimethyl ammonium bromide (DDAB) as surfactant. The increasing liquid temperature resulted in the increased mean bubble size and total bubble number, but this trend became inapparent at high temperatures due to the reduced liquid viscosity. The increasing gas flow rate was favorable to increase the multiphase interfacial area, thus leading to the increasing mass transfer coefficient K L a . The conversion of 1-dodecene reached maximum 95% in the three-phase microemulsion system, and at a gas flow rate of 40 ml min −1 . Further increasing the gas flow rate to 80 ml min −1 decreased the conversion, which was attributed to the destroyed flow field, as observed in micro-PIV. Owing to the increased multiphase mass transfer efficiency, the application of microbubbles allowed to intensify the hydroformylation reaction with reduced reaction pressure, higher chemoselectivity, and increased turnover frequency (TOF).
研究领域:
化学工程
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催化化学
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高影响因子
Asia-Pacific Journal of Chemical Engineering
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2023
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IF 1.8
Liang Shen,Zihan Li,Jiabao Gong,Lingyun Liu,Erle Qiao,Yifang Liu,Fanfei Min
With the deterioration of underground coal quality, hundreds of millions of tons of coal slime in China need to be treated using flotation methods every year. However, the design and selection of coal slurry flotation collectors lack theoretical guidance. In this paper, the quantitative structure–activity relationship (QSAR) model between the molecular structure descriptors of collectors and the flotation recovery and selectivity index is established by using pure kaolinite/clean coal flotation experiments and molecular simulation techniques. Flotation results showed that the flotation recovery rate of kaolinite by collectors with larger head group size, such as DDMAC, DDP, and DTAC, is higher than that of the other collectors with smaller head group size. DDA, DDP, and DD have similar flotation capabilities for clean coal, and their selectivity was slightly better than others. The QSAR model between the molecular structure descriptor and the selectivity index was successfully constructed by combining flotation experiments and molecular simulation results. The reliability of this model has been proven through theoretical analysis and flotation experiments. The molecular simulation results indicate that all eight collectors can advertise on 001 (−) surface of kaolinite, but the final advertisement configuration is different. DDA has less coverage on the surface of kaolinite. When the collector is DDA, the concentration of water molecules near the 001 (−) surface of kaolinite is the highest, indicating that the collector DDA has the weakest effect on improving the hydrophobicity of the 001 (−) surface of kaolinite. DDMAC and DDBAC have the best facilitation to the surface hydrophobicity of kaolinite 001 (−). The research results have theoretical guidance significance for the selection and design of mineral flotation collectors.
研究领域:
矿物加工工程
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化学工程
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高影响因子
危险品化学品经营许可证（带存储）