Co-reporter:Chao Yu, Shutian Wu, Yang Zhao, Zuoxiang Zeng, and Weilan Xue
Journal of Chemical & Engineering Data August 10, 2017 Volume 62(Issue 8) pp:2244-2244
Publication Date(Web):July 5, 2017
DOI:10.1021/acs.jced.6b00941
Liquid–liquid equilibrium (LLE) data of water + butyric acid + {butanal or n-butanol} ternary systems were determined at T = 293.15, 308.15, and 323.15 K and p = 0.1 MPa. The ternary systems investigated display Type I behavior of LLE. Nonrandom two-liquid (NRTL) and universal quasichemical (UNIQUAC) activity coefficient models were applied here to fit the experimental results, and the root-mean-square deviations (RMSD) between experimental data and calculated ones were considered in the calculation. The results indicated that the LLE data were well-fitted with both models, in which the RMSD were less than 0.0124. Moreover, solute and diluent compositions in each equilibrium phase were used to calculate the distribution coefficient (D) and the selectivity (S).
Co-reporter:Chao Yu;Yang Zhao;Weilan Xue
Journal of Solution Chemistry 2017 Volume 46( Issue 3) pp:738-740
Publication Date(Web):2017 March
DOI:10.1007/s10953-017-0588-9
Co-reporter:Chao Yu, Shutian Wu, Zhijuan Huang, Yang Zhao, Zuoxiang Zeng, Weilan Xue
Journal of Molecular Liquids 2016 Volume 224(Part A) pp:139-145
Publication Date(Web):December 2016
DOI:10.1016/j.molliq.2016.09.094
•We measured solubility of Co(OTs)2·6H2O and Ni(OTs)2·6H2O in water/ethanol mixtures.•The experimental data were correlated by the (CNIBS)/Redlich-Kister model.•We proposed two possible water/ethanol clusters [(water)2-ethanol, water-(ethanol)3].•Five special values of x0 were obtained by the (CNIBS)/Redlich-Kister model.•We calculated the hydrogen-bond between solute and solvent by Materials Studio DMol3.Water/ethanol complexation inducing solubility variation of transition-metal p-toluenesulfonates (tosylates) was investigated. The solubilities of hexaquocobalt(II) bis (p-toluenesulfonate) [Co(OTs)2·6H2O] and hexaquonickel(II) bis (p-toluenesulfonate) [Ni(OTs)2·6H2O] in water/ethanol mixtures were measured at T = 298.15 K. All the experimental data were well-correlated by the (CNIBS)/Redlich-Kister model. A distinct variation phenomenon of solubility was observed when the mole fraction of ethanol (x0) changed from 0.000–1.000. Based on the experimental data, two kinds of possible water/ethanol clusters [(water)2-ethanol and water-(ethanol)3] were proposed, and five special values of x0 (x0,1 − x0,5) were obtained by a mathematical study of the (CNIBS)/Redlich-Kister model. The interactions of hydrogen bonds between tosylates and water (or ethanol, water/ethanol clusters) were calculated by Materials Studio DMol3. The formation and change of the above clusters at special values of x0 were analyzed, based on which, the variation of solubility induced by water/ethanol complexation was investigated.
Co-reporter:Chao Yu;Zhijuan Huang;Weilan Xue
Journal of Solution Chemistry 2016 Volume 45( Issue 3) pp:395-409
Publication Date(Web):2016 March
DOI:10.1007/s10953-016-0443-4
The solubilities of hexaquocobalt(II) bis(p-toluenesulfonate) [Co(OTs)2·6H2O] in water and ethanol mixed solvents with ethanol mole fractions of 0–0.342 were determined from 288.15 to 333.15 K by a synthetic method. The generated data were well correlated with the modified Apelblat equation, the Redlich–Kister (CNIBS/R–K) model, and the hybrid model in which the mean deviations are less than 3.06 %. Materials Studio DMol3 (Accelrys Software Inc.) was chosen to investigate the molecular modeling. The results indicated that the increase of solubility of Co(OTs)2·6H2O with increase of the initial mole fraction of ethanol (x2) is due to stronger interactions occurring between ethanol and Co(OTs)2·6H2O. Moreover, this tends to level out when x2 is greater than 0.228 because some new clusters will be formed by the water and ethanol molecules in the binary mixture. The modified van’t Hoff equation was adopted to analyze the enthalpy, entropy, and Gibbs energy, indicating the dissolution process of Co(OTs)2·6H2O in mixed solvents is endothermic, spontaneous, and entropy driven.
Co-reporter:Chao Yu, Zuo-Xiang Zeng, and Wei-Lan Xue
Industrial & Engineering Chemistry Research 2015 Volume 54(Issue 15) pp:3961-3967
Publication Date(Web):March 27, 2015
DOI:10.1021/ie5049753
The solubilities of hexaquonickel(II) bis(p-toluenesulfonate) [Ni(OTs)2·6H2O] in an ethanol–water mixture containing a mole fraction of 0−0.342 ethanol were measured at temperatures ranging from 288.15 to 333.15 K by using a synthetic method. The experimental data were fitted using the van’t Hoff plot, the modified Apelblat equation, the general single model, and the hybrid model. All of these models show good agreement with the experimental data. The solubility of Ni(OTs)2·6H2O increases with an increase of the temperature and the initial mole fraction of ethanol in the mixed solvents. Further, the molecular modeling studies using Materials Studio DMol3 (Accelrys Software Inc.) indicated that the solubility of Ni(OTs)2·6H2O depends not only on the polarities of the solvents but also on the interactions between Ni(OTs)2·6H2O and solvent molecules. The enthalpy, Gibbs energy, and entropy of the solution process were derived by the modified van’t Hoff equation.
Co-reporter:Zhi-Hong Yang, Zuo-Xiang Zeng, Li Sun, Wei-Lan Xue, and Nan Chen
Journal of Chemical & Engineering Data 2014 Volume 59(Issue 9) pp:2725-2731
Publication Date(Web):August 14, 2014
DOI:10.1021/je500222s
The solubilities of lauric acid in methanol, ethanol, propanol, n-butanol, n-pentanol, n-hexanol, isobutanol, and isoamylol were measured by synthetic method in the temperature ranging from (276.17 to 306.12) K. Results of these measurements were correlated by the modified Apelblat equation, the λh equation and activity coefficient models (NRTL and UNIQUAC). It was found that the modified Apelblat equation and the λh equation gave better correlation results. The thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated by the van’t Hoff analysis.
Co-reporter:Zuoxiang Zeng;Hailing Zhang;Weilan Xue;Wanyu Zhu;Xiaoling Xiao;Yu Sun;Zhelong Li
Journal of Applied Polymer Science 2011 Volume 121( Issue 2) pp:735-742
Publication Date(Web):
DOI:10.1002/app.33814
Abstract
Poly(butylene terephalate) (PBT) and poly(butylene terephthalate-co- sebacate) (PBTS) copolymers containing 5 mol % and 10 mol % sebacate components (Mn = 12,700–14,600) were synthesized by polycondensation. The isothermal crystallization kinetics and melting behaviors after isothermal crystallization of the polymers were investigated by differential scanning calorimetry (DSC). The equilibrium melting temperatures of the polymers were determined by Hoffman-Weeks equation. Analysis of the crystallization kinetic data using the Avrami equation showed that the introduction of sebacate enhanced the crystallization of PBT in PBTS. And the Avrami exponent n varies in the range of 2.16–3.68, indicating that the isothermal crystallization follows two- and three-dimensional growth mechanism. The isothermal crystallization activation energies of the polymers were also calculated by the Arrhenius equation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Co-reporter:Na Yin;Zuo-Xiang Zeng;Wei-Lan Xue
Journal of Applied Polymer Science 2010 Volume 117( Issue 4) pp:1883-1887
Publication Date(Web):
DOI:10.1002/app.32058
Abstract
The relationship between number average molecular weight (Mn) and intrinsic viscosity ([η]) was studied for poly(1,4-butylene adipate) diol (PBAD) in tetrahydrofuran, toluene, and ethyl acetate at 25°C. Thus, a series of PBAD samples were prepared by polymerization between 1,6-adipic acid and 1,4-butanediol. The values of Mn for the samples were determined by end-group analysis as well as by ebulliometry, and the average difference of Mn between the two analysis ways was about 2.69%. The Mark–Houwink–Sakurada equations for PBAD were obtained to relate [η] with Mn in the range of 1900–10,000. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Co-reporter:Zuoxiang Zeng, Li Sun, Weilan Xue, Na Yin, Wanyu Zhu
Polymer Testing 2010 Volume 29(Issue 1) pp:66-71
Publication Date(Web):February 2010
DOI:10.1016/j.polymertesting.2009.09.006
The relationships between molecular weight and intrinsic viscosity were established for poly(1, 4-butylene adipate) (PBA) with the molecular weight Mw ≤ 20,000 in tetrahydrofuran at 298 K. Thus, two series of PBA samples having narrow and broad molecular weight distributions (MWD) were prepared by polymerization between 1,6-adipic acid and 1,4-butanediol. The number average molecular weights (Mn) of the samples were measured by end-group analysis. Size-exclusion chromatography (SEC) was used to determine average molecular weights (Mn, Mv, Mw and Mz). A numerical method for determination of Mark-Houwink-Sakurada (MHS) equation constants, a and K , was tested with success for the PBA samples, and the influences of polydispersity correction factor (qMHS)(qMHS) on the relationships were studied for PBA with narrow MWD(1.065-1.181) and broad MWD (1.75-2.327).
Co-reporter:Zuoxiang Zeng, Zhihong Yang, Weilan Xue, Xiaonan Li
Chinese Journal of Chemical Engineering (October 2014) Volume 22(Issue 10) pp:1145-1152
Publication Date(Web):1 October 2014
DOI:10.1016/j.cjche.2014.08.003
The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equation and the second virial coefficient was determined by the Vetere model. Then the standard enthalpy of vaporization for n-butyl carbamate was estimated. The heat capacity was measured for the solid state (299.39–324.2 K) and liquid state (336.65–453.21 K) by means of adiabatic calorimeter. The standard enthalpy of formation ΔfHθ[crystal (cr),298.15 K] and standard entropy Sθ(crystal,298.15 K) of the substance were calculated on the basis of the gas-phase standard enthalpy of formation ΔfHθ(g,298.15 K) and gas-phase standard entropy Sθ(g,298.15 K), which were estimated by the Benson method. The results are acceptable, validated by a thermochemical cycle.The vapor pressures of n-butyl carbamate (BC) were measured in the temperature range from 372.37 K to 479.27 K. The plot of lgp of n-butyl carbamate against lgp′ of ethyl butyrate in the temperature range shows that lgp/lgp′ is constant and independent of temperature, which is used to calculate ΔvapHθ(298.15 K) of BC by the Othmer method.Download full-size image
Co-reporter:Weilan XUE, Dan WANG, Zuoxiang ZENG, Xuechao GAO
Chinese Journal of Chemical Engineering (February 2013) Volume 21(Issue 2) pp:177-184
Publication Date(Web):1 February 2013
DOI:10.1016/S1004-9541(13)60456-5
On the basis of energy conservation law and surface pressure isotherm, the conformation energy changes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) in pure phospholipid monolayer at the air/water interface during compression are derived. The optimized conformations of phospholipids at absolute freedom state are simulated by Gaussian 98 software. Based on following assumptions: (1) the conformation energy change is mainly caused by the rotation of one special bond; (2) the atoms of glycerol near the water surface are active; (3) the rotation is motivated by hydrogen-bond action; (4) the rotation of bond is inertial, one simplified track of conformational change is suggested and the conformations of DPPC and DPPG at different states are determined by the plots of conformation energy change vs. dihedral angle. The thickness of the simulated phospholipid monolayer is consistent with published experimental result. According to molecular areas at different states, the molecular orientations in the compressing process are also developed.
Co-reporter:Wenyu TIAN, Weilan XUE, Zuoxiang ZENG, Ji SHAO
Chinese Journal of Chemical Engineering (February 2009) Volume 17(Issue 1) pp:72-77
Publication Date(Web):1 February 2009
DOI:10.1016/S1004-9541(09)60035-5
In this paper, a kinetics model for the liquid-phase oxidation of 2-methyl-6-acetyl-naphthalene to 2,6-naphthalene dicarboxylic acid catalyzed by cobalt-manganese-bromide is proposed. The effects of the reaction temperature, catalyst concentration and ratio of catalyst on the time evolution of the experimental concentration for theconstituents including raw material, intermediates and product are investigated. The model parameters are determined in a nonlinear optimization, minimizing the difference between the simulated and experimental time evolution of the product composition obtained in a semi-batch oxidation reactor where the gas and liquid phase were well mixed. Thekinetics data demonstrate that the model is suitable to the liquid-phase oxidation of 2-methyl-6-acetyl-naphthalene to 2,6-naphthalene dicarboxylic acid.
Co-reporter:Wenyu TIAN, Zuoxiang ZENG, Weilan XUE, Yingbin LI, Tianyu ZHANG
Chinese Journal of Chemical Engineering (2010) Volume 18(Issue 3) pp:391-396
Publication Date(Web):1 January 2010
DOI:10.1016/S1004-9541(10)60236-4
The chemical kinetics of the monoesterification between terephthalic acid (TPA) and 1,4-butanediol (BDO) catalyzed by a metallo-organic compound was studied using the initial rate method. The experiments were carried out in the temperature range of 463-483 K, and butylhydroxyoxo-stannane (BuSnOOH) and tetrabutyl titanate [Ti(OBu)4] were used as catalyst respectively. The initial rates of the reaction catalyzed by BuSnOOH or Ti(OBu)4 were measured at a series of initial concentrations of BDO (or TPA) with the concentration of TPA (or BDO) kept constant. The reaction orders of reagents were determined by the initial rate method. The results indicate that the reaction order for TPA is related with the species of catalyst and it is 2 and 0.7 for BuSnOOH and Ti(OBu)4 respectively. However, the order for BDO is the same 0.9 for the two catalysts. Furthermore, the effects of temperature and catalyst concentration are investigated, and the activation energies and the reaction rate constants for the two catalysts were determined.
![Poly[imino(1,10-dioxo-1,10-decanediyl)imino-1,10-decanediyl]](http://img.cochemist.com/ccimg/28800/28774-87-0.png)
![Poly[imino(1,10-dioxo-1,10-decanediyl)imino-1,10-decanediyl]](http://img.cochemist.com/ccimg/28800/28774-87-0_b.png)
