【摘要】 根据Flory-Huggins模型和Wilson方程,建立了聚乙烯醇(PVA)膜渗透汽化分离异丙醇水溶液过程的溶胀平衡数学模型,模型计算值与实验值吻合良好.水与PVA膜的相互作用参数小于异丙醇与PVA膜的相互作用参数,说明水在PVA膜中优先吸附溶解,PVA膜可作为优先透水膜实现异丙醇水溶液的分离.异丙醇与水之间的相互作用参数随溶液中异丙醇浓度的升高而增大,说明异丙醇含量越高,膜的溶胀选择性越好,越有利于水在膜中的溶解透过,渗透汽化分离效果越好.模型计算结果表明,随溶液中异丙醇浓度的升高,PVA膜中水浓度逐渐下降,而异丙醇浓度先升高,当溶液中异丙醇摩尔分率超过0.1后趋于稳定,与实验结果一致.更多还原

【Abstract】 Based on the Flory-Huggins model and Wilson equation, the swelling balance mathematical model of the pervaporation process of isopropanol/water mixtures using polyvinyl alcohol(PVA) membrane was established.And the calculated values agreed well with the experimental data.The interactional parameter between water and PVA membrane is less than that between isopropanol and PVA membrane,which shows that water is preferentially adsorbed and dissolved in PVA membrane as a high hydrophilic membrane.The interactional parameter between water and isopropanol rises with an increase of isopropanol content in the mixture,which shows that the larger isopropanol content is,the higher swelling selectivity of the membrane is.So it is more advantageous to dissolution and permeation of water,which results in remarkable separation effect of pervaporation.The calculated results of the model,in a good agreement with experimental results,illuminate that,with the growth of isopropanol content in mixture,water content in PVA membrane decreases,while isopropanol content in PVA membrane increases at first,and then tends to invariableness when the mole fraction of isopropanol is beyond 0.1.更多还原