FUEL PROCESSING TECHNOLOGY
·
2016
·
IF 3.847
Yong-gang Wang,Guang-ce Jiang,Sheng-juan Zhang,Hai-yong Zhang,Xiong-chao Lin,Xin Huang,Mao-hong Fan
The selectivity of organic solvent extraction for separating non-aromatic hydrocarbons, aromatic hydrocarbons and polar components in low-temperature coal tar was enhanced by applying the Hansen Solubility Parameters theory. The relationship between solubility parameter “distance” ( R a ) and solubility was obtained by turbidimetric titration, thus allowing an approximate comparison of dissolving properties between different solvents and the typical model compound (solute). A modified dissolving model in terms of the Hansen solubility sphere was established in order to select the extraction solvent. In practice, the low-temperature coal tar was successfully divided into three parts (i.e., enriching non-aromatic hydrocarbons, aromatic hydrocarbons and polar components) by a three-step extraction-precipitation process at 298 K and 1 atm. Experimental results demonstrated a high correlation with the estimation made by the ellipsoidal model. The mass percentage of non-aromatic hydrocarbons, aromatic hydrocarbons and polar components in their separation products were all ca. 90 wt.%. The mass percentages of the three products in total feedstock were around 12%, 46% and 36%, respectively. The mass loss during the entire separation process was from 4.5% to 6.0%.
研究领域:
能源化学
·
煤化工
·
分离科学
·
物理化学
·
应用化学
·
材料化学
·
过程工程
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Yu Dong,Tiantian Ping,Xiaoqin Shi,Shufeng Shen
Nonaqueous amine-based blends have great potential for energy-efficient CO 2 absorbent. In this work, densities and viscosities were measured for liquid binary mixtures of 2-(ethylamino)ethanol (EAE) and 2-(butylamino)ethanol (BAE) with 2-butoxyethanol (EGBE) at temperatures of (293.15–353.15)K over the entire concentration range and atmospheric pressure. Intermolecular interactions between EGBE and two secondary amines with different carbon chain length were discussed. The excess molar volume ( V E ), viscosity deviations ( ∆η ) and excess Gibbs free energy ( ∆G ⁎ E ) were calculated from the experimental data and also correlated with the Redlich-Kister equation to estimate the binary interaction parameters. The experimental data and the calculated from the proposed correlations for the studied binary mixtures matched well each other, with AADs within 0.01% and 1.45% for density and viscosity respectively. The variation of excess properties was also discussed in terms of intermolecular interactions. Weak interactions on mixing these binary mixtures with different mass fractions were observed from the FTIR spectra analysis.
研究领域:
化学工程
·
热力学
·
流体物理化学
·
气体吸收
·
分离科学
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DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Zhanjing Guo,Xiongmin Liu,Hongmiao Huang,Lingfeng Jiang
The strong acidic cationic exchange fiber (SACEF) was used to adsorb yohimbine from alcoholic solution. Batch experiments were performed to examine the effects of adsorbent dosage, solution pH and temperature in the adsorption process. The thermodynamics and kinetics of adsorption were also analyzed. The optimum yohimbine adsorption onto the SACEF was found at pH = 5 of solution and equilibrium could be attained within 20 min. The equilibrium adsorption data were preferably modeled with the Freundlich isotherm model and the thermodynamic parameters were calculated to be: 11.99 kJ/mol < Δ H < 13.72 kJ/mol, −21.17 kJ/mol < Δ G < −17.87 kJ/mol and 63.18 J/mol K < Δ S < 65.60 J/mol K. The results demonstrated that the adsorption was an endothermic, spontaneous and feasible process of physisorption . Meanwhile, yohimbine adsorption on SACEF fitted well to the pseudo-second-order kinetic model and the adsorption rate was limited by film diffusion. The activation energy Ea was calculated to be 14.39 kJ/mol. Furthermore, the surface morphologies of the SACEF before and after yohimbine adsorption were analyzed by SEM and the adsorption mechanism was discussed by FTIR analysis. SACEF could effectively adsorb yohimbine from alcoholic solution and could be used repeatedly for more than five cycles.
研究领域:
药物化学
·
药剂学
·
物理化学
·
分离科学
·
吸附科学
·
天然产物提取
·
药物代谢
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Qi Liu,Xiaoxiao Chen,Yan Guo,Chuanhong Han,Jing Li,Lihan Jia,Jie Liu,Xilian Wei
A ternary phase diagram of the system of 1-butyl-3-methylimidazolium tetrafluoroborate ([ Bmim ]BF4), sodium dodecylbenzenesulfonate (SDBS) and water using ocular estimate and turbidity method was drawn based on experimental data at 298.2 K. We got a narrow aqueous two-phase region near the side of water-ionic liquid (IL). A series of samples with different compositions around the phase diagram were chosen. The enthalpy change of these systems after injecting triply distilled water into these samples has been studied by using isothermal titration microcalorimetry (ITC). It is found that with increasing the water content there are weak endothermic and exothermic processes appearing, separately, which matches perfectly with the location of the formation and disappearance of the aqueous two-phase in the ternary phase diagram. This suggests the ITC is a feasible and effective method for the thermodynamic study of aqueous two-phase systems (ATPS) and was first reported. The experimental results show that the formation of the ATPS is endothermic (Δ H > 0), but the process of disappearing is exothermic (Δ H < 0). Due to the formation of aqueous two-phase is a thermodynamic spontaneous process under the isothermal constant pressure, we can judge that the formation of this ATPS is an entropy driven course and the vanishing is a synergy driven process by entropy and enthalpy.
研究领域:
物理化学
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热力学
·
胶体与界面化学
·
分离科学
·
分析化学
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DOI
高影响因子
DESALINATION
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2019
·
IF 6.035
Yuchen Wu,Mingfu Gao,Weitao Chen,Zhenhua Lü,Sanchuan Yu,Meihong Liu,Congjie Gao
In this work, nanofiltration membrane with an asymmetric selective separation layer and improved surface negative charge was designed and fabricated to efficient remove anionic dyes from aqueous solution. Firstly, loose polyester selective separation layer was formed through interfacial polymerization of triethanolamine and trimesoyl chloride. Surface carboxylation was then implemented via esterification using poly(acrylic acid) to generate a dense skin. Membrane characterizations verified the asymmetric structure and enrichment of surface carboxyl group, which endowed the carboxylated membrane with improved perm-selectivity and anti-dye-deposition property to anionic dye aqueous solutions. The desired surface carboxylated membrane exhibited 99.6% methyl blue removal, 8.05 l/m 2 h bar steady-state water permeability and 14.3% relative flux decline ratio under 5.0 bar. The water permeability of carboxylated membrane to methyl blue aqueous solution was higher than those of most reported membranes and even at least two times higher than that of the polyester-based membrane having nearly the same dye removal ability. The attractive results indicate that surface carboxylated polyester based thin-film composite membrane is a promising material for high-efficiency nanofiltration of anionic dye aqueous solution. This study provides valuable insights into the construction and fabrication of high performance nanofiltration membrane for efficient treatment of anionic dye aqueous solution.
研究领域:
环境工程
·
膜科学与技术
·
水处理
·
材料化学
·
纳米技术
·
分离科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Jianxian Zeng,Zhihui Dong,Zhe Zhang,Yuan Liu
A surface-grafted imprinted ceramic membrane (IIP-PVI/CM) for recognizing molybdate (Mo(VI)) anion was prepared by surface-initiated graft-polymerization. Firstly, raw alumina ceramic membrane (CM) was deposited with SiO 2 active layer by situ hydrolysis deposition method. Subsequently, γ-methacryloxy propyl trimethoxyl silane (MPS) was used as a coupling agent to introduce double bonds onto the SiO 2 layer (MPS-CM). Then, 1-vinylimidazole (VI) was employed as a functional monomer to graft-polymerization onto the MPS-CM (PVI-CM). During the graft-polymerization, the influence factors of grafting degree of PVI were investigated in detail. Under optimum conditions (monomer concentration 20 wt%, temperature 70 °C, initiator amount 1.1 wt% and reaction time 8 h), the grafting degree of 20.39 g/100 g was obtained. Further, Mo(VI) anion was used as a template to imprint in the PVI-CM by employing 1,6-dibromohexane as a cross-linking agent, and then Mo(VI) was removed, obtaining the IIP-PVI/CM with many imprinted cavities for Mo(VI). Thereafter, static adsorption and dynamic separation properties of IIP-PVI/CM for Mo(VI) were studied. Results indicate that IIP-PVI/CM shows a specific selectivity for Mo(VI) with the adsorption capacity of 0.69 mmol/100 g, and the selectivity coefficient of IIP-PVI/CM is 7.48 for molybdate to tungstate anions. During the dynamic separation, IIP-PVI/CM has also good selectivity for separation of Mo(VI) and W(VI) anions.
研究领域:
环境化学
·
材料科学
·
分离科学
·
高分子化学
·
无机分析化学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yan-zhen Shen,Xun-liang Wang,Yu-xiang Jia,Meng Wang
The endowment of perm-selectivity for specific ions will further extend the applications of heterogeneous membrane. In this work, a side-chain type weak cationic polyelectrolyte, PVDF-g-PVP, was synthesized for surface hydrophobilization of heterogeneous anion-exchange membrane (AEM) in order to impart perm-selectivity between specific anions with different Gibbs hydration energy. After microstructure observation and chemical composition analyses by SEM, AFM, EA and FTIR, the perm-selectivity between specific anions, electrical resistance, transport number, limiting current density, surface homogeneity, as well as salt permeability of the modified AEMs were investigated. Series of electrodialysis experiments in SO 4 2– /Cl – system indicated that a significant perm-selectivity was indeed achieved by the attachment of PVDF-g-PVP coating. In particular, it was worth noting that only a small loss of membrane conductivity was observed after the functionalization. This should be closely related to the micro-phase separation morphology of the coating layer which was induced by the polarity difference between the main chains and side chains of PVDF-g-PVP. Besides, the chronopotentiometric analyses indicated surface homogeneity of the heterogeneous AEM was significantly enhanced and then effectively ameliorated concentration polarization behaviors at the membrane-solution interface. Meanwhile, the perm-selectivity for co-ions was also improved and suppressed back diffusion behaviors of salt driven by concentration gradient. In brief, the modifying scheme proposed in this work can effectively improve comprehensive transport properties of conventional heterogeneous AEM.
研究领域:
膜科学与技术
·
高分子材料化学
·
分离科学
·
电化学工程
·
功能材料
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2011
·Vol. 29
·期 4
·778-782
·
IF 0.773
Haining Shi,Zonghua Wang,Hui Wang,Rui Zhao,Mingyu Ding
An anion-exchange chromatography method combined solid phase extraction (SPE) was developed for the simultaneous analysis of glycolate acid (GL), monochloroacetic acid (MCA) and dichloroacetic acid (DCA) in synthetical betaine products. The analytes and unknown anionic impurities were well separated on a Metrosep A supp5 anion-exchange column (150 mm×4 mm) with 2.0 mmol/L Na 2 CO 3 +2.0 mmol/L NaHCO 3 solution as eluent. Suppressed conductivity detection was used. A strong cation exchange (SCX) solid phase extraction (SPE) cartridge was used to reduce the concentration of matrix betaine and a Cleanert IC-Ag pretreatment cartridge was used to remove high Cl − concentration. The detection limits of GL, MCA and DCA were 0.09, 0.017 and 0.05 µg/L, respectively. The relative standard deviations (RSDs) of the retention times and peak areas were less than 0.09% and 0.49%, respectively. The recoveries of the three analytes were between 90.6% and 100.8%. The analytical results showed that GL and DCA were present in high concentration and no MCA was found when the proposed ion chromatography method was applied to three synthetical betaine samples. The proposed method is simple, sensitive and timesaving, and is also suitable for routine analysis in quality control of synthetical betaine products.
研究领域:
分析化学
·
药物质量控制
·
分离科学
·
环境分析
·
食品化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2024
·
IF 8.1
Meng Wang,Rongkang Yan,Meng Shan,Shasha Liu,Hai Tang
Adsorptive separation membranes are widely utilized for the removal of toxic dyeing pollutants from dyeing wastewater. However, developing novel adsorption membranes with large adsorption capacities and enhanced adsorption performance for dyes in actual wastewater poses a significant challenge. This study focuses on the fabrication of crown ether-containing copolymer porous membrane (CRPM) and investigation of the adsorption performance of dyes from aqueous solutions. The morphology structure and pore size distribution revealed that the membrane was endowed with rich micropores and hierarchical porous structures. Three typical cationic dyes (MB, RhB, CV) and an anionic dye (MO) were selected to evaluate the adsorption behavior. The results of adsorption isotherms and kinetics demonstrated that the adsorption data could be well-fitted using the Freundlich and pseudo-first-order kinetic models, the thermodynamic parameters revealed that the adsorption process of dyes on CRPM is a spontaneous endothermic reaction. The membrane exhibited excellent adsorption performance for cationic dyes, with RhB displaying a higher maximum adsorption capacity than previously reported porous membranes. Notably, dynamic adsorption-desorption filtration demonstrated a rapid removal efficiency, with RhB, MB, and CV achieving removal rates of 99.09%, 98.63%, and 99.14% respectively, after five cycles. The filtration volume of the CRPM membrane was 2.4-fold greater than that of a traditional PVDF membrane when applied to actual dyeing wastewater. DFT theoretical calculations were employed to elucidate the adsorption mechanism. These calculations confirmed the significant roles of electrostatic interactions, H-bonds and π–π interactions in facilitating the high-efficiency adsorption of cationic dyes. These findings highlight the potential of the crown ether-containing copolymer as a promising material for adsorption separation membranes in the treatment of dyeing wastewater.
研究领域:
环境科学
·
材料科学
·
高分子化学
·
分离科学
·
物理化学
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DOI
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2015
·Vol. 43
·期 10
·1569-1572
·
IF 0.754
Ming-Yan LUO,Bei LÜ,Guo-Bin SHEN,Fei-Fang ZHANG,Bing-Cheng YANG
Electrodialytic eluent generator, one of the key components of ion chromatography system, was fabricated and evaluated. The data achieved indicated that its performance could be comparable to that of commercial one. The maximal operation pressure was over 20 MPa, the generated KOH concentration was up to 100 mM, and the designed usage lifetime was about 354 day (take 8 h working time per day). This device will be helpful to the improvement of domestic instruments of ion chromatography.
研究领域:
分析化学
·
仪器科学与技术
·
分离科学
·
离子色谱技术
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2022
·Vol. 52
·期 2
·376-383
·
IF 4.569
Enming Ping,Lingyun Kong,Mengyao Liu,Yunshan Zhou,Lijuan Zhang,Nan Chen
The reaction of porous γ-Al2O3 particles acting as both a sacrificial template and an aluminum source with 1,4-naphthalene diacid (H2NDC) resulted in the formation of γ-AlOOH@Al(OH)(1,4-NDC) composites, in which ZIF-67 was then loaded by the in situ crystallization method, leading to the formation of γ-AlOOH@Al(OH)(1,4-NDC)@ZIF-67 composites. The deliberately designed composite was used to separate H2/D2 at 77 K in a 1 m chromatographic column. The results demonstrated that the optimized composite can achieve the effective separation of H2/D2 in gas chromatography due to the additive effects of kinetic sieving and chemical affinity quantum sieving of Al(OH)(1,4-NDC) and ZIF-67. By optimizing chromatographic separation conditions, the resolution R reached 2.02 with the separation time t = 7.72 min. The composite also showed satisfactory repeatability and reproducibility.
研究领域:
材料科学
·
分离科学
·
物理化学
·
纳米材料
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 129
·期 6
·3473-3481
·
IF 1.395
Wan-Zhong Lang,Hai-Yan Niu,Ya-Xin Liu,Chun-Xia Liu,Ya-Jun Guo
The waste perfluoro-ion-exchange membranes (PFIEMs) in chlor-alkali industry were regenerated and used to the separation of dimethyl carbonate (DMC)/methanol (MeOH) mixtures by pervaporation process. The energy-dispersive spectrum (EDS) demonstrates that the impurities on the surfaces of waste PFIEMs can be effectively cleared by the regeneration process. The degree of swelling, sorption, and pervaporation properties of the regenerated PFIEMs with different counter ions were investigated. The results indicate that the counter ions of PFIEMs conspicuously influence the degree of swelling, sorption, and pervaporation properties for DMC/MeOH mixtures. The degree of swelling and solubility selectivity both decreases with the alkali metal counter ions in the sequence: Li + > Na + > K + > Cs + . The degree of swelling increases with MeOH concentration increasing in feed liquid. The pervaporation measurements illustrate that the permeation flux decreases and the separation factor increases with the rising in ion radius of counter ions. The increase of feed concentration (MeOH) and feed temperature is advantageous to improve permeation flux while at the cost of separation factor decreasing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
高分子材料
·
化学工程
·
膜科学与技术
·
环境化工
·
分离科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）