INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Weiping Luo,Mengqi Yan,XiaoXiao Sheng,Bao Tao,Sile Shi,Wei Deng,Weijun Yang,Siqi Luo
The solubility of adipic acid (AA), glutaric acid (GA), and succinic acid (SA) in acetic acid (HAc) + cyclohexanol solvent mixtures was measured by the laser dynamic method. The experimental temperature ranged from 300.75 to 347.05 K, and the mole fraction of HAc in the solvent mixtures ranged from 0.0000 to 1.0000. Together with the available solid–liquid equilibrium (SLE) and liquid–liquid equilibrium (LLE) data of the oxidation for cyclohexane in the published literatures, the interaction parameters of the NRTL (non-random two-liquid) model are determined by correlating a large number of experimental data. By using the new interaction parameters, the NRTL model predicted vapor–liquid equilibrium (VLE), SLE, and LLE data well in extrapolating temperature and solvent composition for the cyclohexane oxidation systems, which was in agreement with the experimentally determined results and was satisfactorily in agreement with previously published literatures. The results showed that the NRTL model would be a suitable one for the unified thermodynamics model which can be used for the correlation and prediction of the SLE, LLE, and VLE data for the cyclohexane oxidation process.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2022
·
IF 2.745
Jingjun Liu,Dandan Pan,Qing Zhang,Yulei Guan,Bolun Yang
Phase splitting and merging exist in the glycerol transesterification with diethyl carbonate. This work measured the liquid-liquid equilibrium data for two ternary systems (glycerol – diethyl carbonate – glycerol carbonate/ethanol) and one quaternary system (glycerol – diethyl carbonate – glycerol carbonate – ethanol) involved in the glycerol transesterification at various temperatures (343.2 K, 363.2 K, 383.2 K, and 403.2 K) and 1.5 MPa. The equilibrium data were correlated using the NRTL as the activity coefficient model, and the corresponding binary interaction parameters were estimated and validated by checking the consistency of the Gibbs free energy and phase stability for all mixtures in both the immiscible and homogeneous regions. The NRTL model with the regressed parameters could tightly capture the phase equilibrium trends of the systems.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2019
·
IF 2.514
Xianming Zhang,Yufeng Hu,Weiting Ma,Jianguang Qi,Shuqin Mo
The salt effect on vapor–liquid phase equilibrium (VLE) has potential applications in industrial production of 1,3,5-trioxane. Optimizing reactive distillation process and developing new catalysts for industrial production of 1,3,5-trioxane require a reliable model for VLE of the reaction mixtures. Here an extended UNIFAC model combined a Debye–Hückel type is developed to describe the vapor–liquid and chemical equilibria of the multi-solvent salt-containing reactive mixtures associated with the 1,3,5-trioxane synthesis. New experimental data for the VLE of the quinary systems (formaldehyde + 1,3,5-trioxane + methanol + salt + water) and their ternary subsystems (1,3,5-trioxane + salt + water), (methanol + salt + water), and (formaldehyde + salt + water) are systematically measured at atmospheric pressure. The salts considered include LiCl, NaCl, KCl, NaBr, MgSO 4 , MgCl 2 , and Na 2 SO 4 . The model parameters, which are either obtained from the literature or determined from the VLE data of the above-mentioned ternary systems , are used to provide predictions for the quinary systems (formaldehyde + 1,3,5-trioxane + methanol + salt + water). The agreements between measured and predicted results are accurate. Furthermore, the model is used to uncover the effects of the salts considered on the VLE of these chemical reactive systems. The results show that MgSO 4 is a potential additive that can be used to improve the vapor–liquid phase separation during the reactive distillation process of 1,3,5-trioxane production.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2019
·Vol. 95
·期 3
·719-729
·
IF 2.659
Siqi Jiang,Xianming Zhang,Yufeng Hu,Liuyi Yin,Jianguang Qi,Chunxiao Ren,Shuqin Mo
BACKGROUND Trioxane (C 3 H 6 O 3 ) is industrially produced from aqueous formaldehyde (HCHO) solutions through catalytic distillation catalyzed by sulfuric acid (H 2 SO 4 ). Optimizing industrial process of the synthesis and developing new catalysts require a reliable model for the vapor–liquid equilibria in reaction mixture HCHO–C 3 H 6 O 3 –H 2 SO 4 – H 2 O and a deep understanding of the role of H 2 SO 4 in the industrial production of trioxane. RESULTS Here the Maurer and co-workers's model and the LIFAC model along with their model parameters were invoked to develop such a model. The vapor–liquid equilibrium data in HCHO–C 3 H 6 O 3 –H 2 SO 4 –H 2 O and HCHO–salt–H 2 O were systematically measured and utilized to determine the newly introduced model parameters. The model thus-established provides a reliable method for calculating and predicting the vapor–liquid and chemical equilibria data in HCHO–C 3 H 6 O 3 –H 2 SO 4 – H 2 O and HCHO–salt–H 2 O. CONCLUSIONS The prediction results uncover that, in addition to its ability to accelerate the reaction, the catalyst H 2 SO 4 has strong abilities to increase the activity of ‘real’ reactant for trioxane synthesis and to promote the phase separation that is very important for drastically increasing the yield of trioxane, reducing the energy requirement for the trioxane synthesis, and decreasing the formation of the by-product formic acid. © 2019 Society of Chemical Industry
研究领域:
化学工程
·
工业催化
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2022
·
IF 2.745
Jingjun Liu,Dandan Pan,Qing Zhang,Yulei Guan,Bolun Yang
Glycerol carbonate is a value-added glycerol derivative, which can be obtained by transesterification with dimethyl carbonate. Phase splitting and merging exist in the transesterification due to the low solubilities of glycerol with dimethyl carbonate. The isobaric liquid-liquid equilibrium data for two ternary systems (glycerol – dimethyl carbonate – glycerol carbonate/methanol) and one quaternary system (glycerol – dimethyl carbonate – glycerol carbonate – methanol) involved in the glycerol transesterification were measured at reaction relevant temperatures (333.2, 353.2, 373.2, and 393.2 K) and 1.5 MPa. The equilibrium data were correlated using the NRTL model to calculate activity coefficients, with temperature-dependent interaction parameters, which were estimated through data regression and validated by checking the consistency of the Gibbs free energy. The NRTL model with the regressed parameters could reproduce the phase equilibrium trends of all the studied systems.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Xiaofang Li,Wei Dai,Jilei Wang,Yougui Yu,Qing Zheng
This study addresses the persistent issue of “acid accumulation and ester reduction” that compromises flavor stability in the Baijiu industry by introducing a novel blending approach informed by chemical thermodynamics. Integrating theoretical analysis with experimental validation, the research determined the equilibrium constants for four key esters, leading to the development of a regulatory model for acid-ester equilibrium. A dynamic multi-batch base Baijiu blending strategy was implemented through simultaneous equations that combine concentration conservation and equilibrium constraints, which compresses the reaction quotient deviations from [0.50, 3.47] to [1.50, 1.63] with a 65 % improvement in ester-acid stability. From a methodological perspective, this study established the first acid-ester dynamic equilibrium model, resolving the empirical blending paradox. From an industrial perspective, this study establishes a theoretical foundation for understanding aging thermodynamics while providing innovative solutions to enhance flavor consistency, contributing to sustainable development in the Baijiu industry through improved standardization.
研究领域:
化学热力学
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食品科学
·
工业化学
·
风味化学
·
工艺优化
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Jun Li,Peng Huang,Xiangbin Sun,Xue Bai,Yufeng He,Rongmin Wang
Conventional N-halamine precursor polymers with excess hydrophilic/hydrophobic and rigid/flexible groups have failed to achieve a co-balanced effect of amphiphilicity and rigidity-flexibility. To overcome this problem, hydantoin terpolymer nanohemispheres (P(AMH-St-BA)NHs) were synthesized by regulating both hydrophilic/hydrophobic and rigid/flexible group ratios to 1:1 using emulsion polymerization. Thereafter, a novel N-halamine terpolymer nanohemisphere (P(ClA-St-BA)NHs) with antibacterial activity was fabricated through chlorination treatment. Interestingly, chlorinated nanohemispheres were more dispersed and regularly shaped. Moreover, the effective chlorine content (Cl + ) of P(ClA-St-BA)NHs was detected to be 1.1 % by iodometric/thiosulfate titration, and the existence of N-Cl bonds was supported from the color change of titration. In vitro cytotoxicity suggested that P(AMH-St-BA)NHs possessed superior biocompatibility and safety. Additionally, the antimicrobial performance of samples with three various morphologies was investigated, discovering that the antibacterial rates of P(ClA-St-BA)NHs up to 89.5 % and 93.5 % against E. coli and S. aureus , respectively, exhibited a stronger antimicrobial capability than membranous and porous N-halamine copolymers, which reveals that their special shape elevates the property. In parallel, the antibacterial mechanism of nanohemispheres was also explored, and it was recognized that indirectly released Cl + synergizes with direct contact of N-Cl bonds for antibacterial purposes. By designing nanohemispheres, this method helps to provide new thoughts for realizing the co-balancing effects of hydrophilicity/hydrophobicity and rigidity/flexibility.
研究领域:
材料科学
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生物学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Suzhou Dai,Yonggao Yin,Yikai Wang,Xuanlin Liu,Maurizio Peruzzini,Francesco Barzagli
Chemical heat pump based on ammonium carbamate (AC) is a promising low-grade heat utilization technology. It is essential to know the chemical equilibrium properties in the application of AC-based technologies. AC is usually mixed with solvents to realize circulation. However, the existing studies mainly focus on AC in the solid phase. Therefore, the influence of solvents on the chemical equilibrium of AC was experimentally investigated in this work. The results confirm the solvent effect on the equilibrium pressure of AC in the range of 10∼90 °C. For solvents capable of dissolving AC, the equilibrium pressure increases with both AC concentration and temperature. The solvent effect is mainly due to the influence on both the reaction enthalpy and entropy change terms. An equilibrium pressure–temperature–concentration relationship of AC solution is established. These results provide essential parameters for the design and operation of low-grade heat management and utilization systems based on AC.
研究领域:
热力学
·
化学工程
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Jiaming Zhu,Feihu Li,Xiwei Hu,Qunsheng Li,Hongkang Zhao
This study investigates the phase equilibrium behavior of the isopropyl acetate (IAC)-isopropanol (IPA) azeotrope system at 101.3 kPa in the presence of three different imidazolium-based ionic liquids (ILs) as entrainers, 1-butyl-3-methylimidazolium acetate ([BMIM][Ac]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][NTf2]), and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][NTf2]). First, according to the measured vapor–liquid equilibrium (VLE) data of the binary system IAC(1)-IPA(2) and the ternary system IAC(1)-IPA(2)-ILs(3), [BMIM][Ac] in the ternary system produces a strong salting-in effect on IPA, while [BMIM][NTf2] and [HMIM][NTf2] produces a salting-in effect on IAC, and the effect of [BMIM][Ac] is much stronger than [BMIM][NTf2] and [HMIM][NTf2]. This work uses the nonrandom (local) two-liquid equation to correlate the VLE data. The mole fractions of [BMIM][Ac], [BMIM][NTf2], and [HMIM][NTf2] required to exactly eliminate the azeotropic point of the IAC-IPA system are 0.035, 0.144, and 0.206, respectively.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Rui-Zhi Cui,Wu Li,Ya-Ping Dong,Jun Li
The solubilities in the thermodynamic phase equilibria of the LiBr–NaBr–KBr–H2O system and its two subsystems LiBr–NaBr–H2O and LiBr–KBr–H2O at 298.15 K were investigated experimentally by the isothermal solution equilibrium method. Relevant stable-phase diagrams were plotted based on the experimental results. Using Pitzer’s solution model, nonreported mixing parameters ΨLi,Na,Br and ΨLi,K,Br were acquired and the solubilities of three systems were also predicted at 298.15 K. The results show that good agreement was obtained between calculated and experimental values.
研究领域:
物理化学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Dongsheng Jiang,Yuzhe Li,Chao Zhang,Ruifang Wang,Jinpeng Zhu,Wen Chen,Yusi Che,Jilin He
Bayan Obo tailings are rich in niobium and other valuable elements; however, the phase evolution of niobium-bearing slag within these tailings remains poorly understood. This knowledge gap significantly impedes comprehensive utilization of these strategic resources. In this study, a CaO-SiO 2 -Nb 2 O 5 -5%Na 2 O-5%Al 2 O 3 -3%CaF 2 slag system was investigated to examine the phase equilibrium types, compositional characteristics, and distributional evolution under varying w (CaO)/ w (SiO 2 ) ratios and w (Nb 2 O 5 ) contents, using high-temperature equilibrium experiments. Following a 24-hour high-temperature equilibrium treatment at 1473 K under an argon atmosphere, a range of compounds including 13CaO·8SiO 2 ·Nb 2 O 5 ·CaF 2 , 2CaO·4SiO 2 ·Na 2 O·Al 2 O 3 , CaO·Nb 2 O 5 ·NaF, 2CaO·Nb 2 O 5 , and CaO·SiO 2 were identified. An increase in Nb 2 O 5 content coupled with a reduction in the w (CaO)/ w (SiO 2 ) ratio favored the formation of CaO·Nb 2 O 5 ·NaF (pyrochlore phase) and 2CaO·Nb 2 O 5 . These two phases exhibited high Nb concentrations, with the CaO·Nb 2 O 5 ·NaF (pyrochlore) phase containing up to approximately 70% Nb. The optimal smelting conditions for niobium enrichment in the pyrochlore phase were identified within the range of w (CaO)/ w (SiO 2 ) = 0.74∼0.80 and w (Nb 2 O 5 ) = 13.61%∼16.11%.
研究领域:
冶金学
·
材料科学
·
矿物加工
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Pei-Huan Jiang,Chun-Xia He,Shi-Hua Sang,Xing-Liu,Lan-Rong Zhao
The solid–liquid equilibria in the ternary system LiBr–SrBr2–H2O at 273.15, 308.15, and 323.15 K were studied by isothermal dissolution equilibrium method in this work. At three different temperatures, the ternary system LiBr–SrBr2–H2O belongs to hydrate type I saturation. The phase diagram at 273.15 K includes one cosaturation point, two univariant curves, and two crystallization zones corresponding to LiBr·2H2O and SrBr2·6H2O. The other two phase diagrams contain two cosaturation points, three univariant curves, and three crystallization fields corresponding to LiBr·2H2O, SrBr2·2H2O, and SrBr2·6H2O at 308.15 K and LiBr·H2O, SrBr2·2H2O, and SrBr2·6H2O at 323.15 K, respectively. Lithium bromide has an obvious salting-out effect on strontium bromide. The crystallization area of lithium bromide hydrate is the smallest, and lithium bromide is difficult to crystallize out of the solution at different temperatures.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）