Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O（CH2）2O（CH2）2OH] ＋ water from 293.15 to 333.15 K at atmospheric pressur...Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O（CH2）2O（CH2）2OH] ＋ water from 293.15 to 333.15 K at atmospheric pressure, with a capillary pycnometer and Ubbelohde capillary viscometer respectively. From the experimental data, the excess molar volume V^E, viscosity deviation △η, and the excess energy of activation for viscous flow △G^＊E were calculated. These data were correlated by the Redlich-Kister type equations to obtain the coefficients and standard deviations. The results showed a strong molecular interaction between diethylene glycol monoethyl ether and water.展开更多
Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature ...Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature 303.15K. From the experimental densities, viscosities and sound velocity, the excess molar volume (<i>V<sup>E</sup></i>), deviation in viscosity (Δ<i>η</i>) and deviation in isentropic compressibility (Δ<i>K<sub>S</sub></i>) have been calculated. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures.展开更多
A powerful method is necessary for thermodynamic modeling of wax phase behavior in crude oils,such as the perturbed-chain statistical associating fluid theory（PC-SAFT）.In this work,a new approach based on the wax ap...A powerful method is necessary for thermodynamic modeling of wax phase behavior in crude oils,such as the perturbed-chain statistical associating fluid theory（PC-SAFT）.In this work,a new approach based on the wax appearance temperature of crude oil was proposed to estimate PC-SAFT parameters in thermodynamic modeling of wax precipitation from crude oil.The proposed approach was verified using experimental data obtained in this work and also with those reported in the literature.In order to compare the performance of the PC-SAFT model with previous models,the wax precipitation experimental data were correlated using previous models such as the solid solution model and multi-solid phase model.The results showed that the PC-SAFT model can correlate more accurately the wax precipitation experimental data of crude oil than the previous models,with an absolute average deviation less than 0.4 %.Also,a series of dynamic experiments were carried out to determine the rheological behavior of waxy crude oil in the absence and presence of a flow improver such as ethylene–vinyl acetate copolymer.It was found that the apparent viscosity of waxy crude oil decreased with increasing shear rate.Also,the results showed that the performance of flow improver was dependent on its molecular weight.展开更多
文摘Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O（CH2）2O（CH2）2OH] ＋ water from 293.15 to 333.15 K at atmospheric pressure, with a capillary pycnometer and Ubbelohde capillary viscometer respectively. From the experimental data, the excess molar volume V^E, viscosity deviation △η, and the excess energy of activation for viscous flow △G^＊E were calculated. These data were correlated by the Redlich-Kister type equations to obtain the coefficients and standard deviations. The results showed a strong molecular interaction between diethylene glycol monoethyl ether and water.
文摘Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature 303.15K. From the experimental densities, viscosities and sound velocity, the excess molar volume (<i>V<sup>E</sup></i>), deviation in viscosity (Δ<i>η</i>) and deviation in isentropic compressibility (Δ<i>K<sub>S</sub></i>) have been calculated. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures.
文摘A powerful method is necessary for thermodynamic modeling of wax phase behavior in crude oils,such as the perturbed-chain statistical associating fluid theory（PC-SAFT）.In this work,a new approach based on the wax appearance temperature of crude oil was proposed to estimate PC-SAFT parameters in thermodynamic modeling of wax precipitation from crude oil.The proposed approach was verified using experimental data obtained in this work and also with those reported in the literature.In order to compare the performance of the PC-SAFT model with previous models,the wax precipitation experimental data were correlated using previous models such as the solid solution model and multi-solid phase model.The results showed that the PC-SAFT model can correlate more accurately the wax precipitation experimental data of crude oil than the previous models,with an absolute average deviation less than 0.4 %.Also,a series of dynamic experiments were carried out to determine the rheological behavior of waxy crude oil in the absence and presence of a flow improver such as ethylene–vinyl acetate copolymer.It was found that the apparent viscosity of waxy crude oil decreased with increasing shear rate.Also,the results showed that the performance of flow improver was dependent on its molecular weight.
