The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's...The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's law is not applicable if the gas phase is a mixture.This problem can be solved by using UNIQUAC model to calculate the activity coefficient of gas dissolved in the membrane.A method was proposed in this study to obtain the gas-membrane interaction parameter for UNIQUAC model.By the experiments of gas permeation through polydimethylsiloxane PDMS membrane,the solubility coefficients of some gases(N2,CO2,CH4) were measured.Through non-linear fitting UNIQUAC model to the experimental results from this study and in literature(H2,O2,C3H8),the gas-membrane interaction parameters for these gases were obtained.Based on these parameters,the activity coefficients of the dissolved gas were calculated by UNIQUAC model,and their values agree well with the experimental data.These results confirm the feasibility and effectiveness of the proposed method,which makes it possible to better predict gas-membrane solution equilibrium.展开更多
Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^* level with DFT method. Based on the experimental data of aqueous solubility (–lgSw) and n-octa...Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^* level with DFT method. Based on the experimental data of aqueous solubility (–lgSw) and n-octanol/water partition coefficient (lgKow), using the modified theoretical linear solvation energy relation (MTLSER) model, correlation equations that can predict –lgSw and lgKow were developed using structural parameters as theoretical descriptors. The correlation coefficients (r) of these equations are 0.9728 and 0.9967, respectively. These equations were further validated by variance inflation factors (VIF) and t-test methods and then used to predict –lgSw and lgKow values. By comparison, the correlation and predictive ability of our work are more advantageous than those calculated from valence molecular connectivity indices method and molecular topology index method.展开更多
文摘The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's law is not applicable if the gas phase is a mixture.This problem can be solved by using UNIQUAC model to calculate the activity coefficient of gas dissolved in the membrane.A method was proposed in this study to obtain the gas-membrane interaction parameter for UNIQUAC model.By the experiments of gas permeation through polydimethylsiloxane PDMS membrane,the solubility coefficients of some gases(N2,CO2,CH4) were measured.Through non-linear fitting UNIQUAC model to the experimental results from this study and in literature(H2,O2,C3H8),the gas-membrane interaction parameters for these gases were obtained.Based on these parameters,the activity coefficients of the dissolved gas were calculated by UNIQUAC model,and their values agree well with the experimental data.These results confirm the feasibility and effectiveness of the proposed method,which makes it possible to better predict gas-membrane solution equilibrium.
基金Project supported by the 973 National Basic Research Program of China (2003CB415002)the Chinese Postdoctoral Science Foundation (No. 2003033486)
文摘Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^* level with DFT method. Based on the experimental data of aqueous solubility (–lgSw) and n-octanol/water partition coefficient (lgKow), using the modified theoretical linear solvation energy relation (MTLSER) model, correlation equations that can predict –lgSw and lgKow were developed using structural parameters as theoretical descriptors. The correlation coefficients (r) of these equations are 0.9728 and 0.9967, respectively. These equations were further validated by variance inflation factors (VIF) and t-test methods and then used to predict –lgSw and lgKow values. By comparison, the correlation and predictive ability of our work are more advantageous than those calculated from valence molecular connectivity indices method and molecular topology index method.