纳米二氧化硅填充催化与分离双功能复合膜的性能

Performances of Catalytic and Separative Difunctional Composite Membrane Embedded with Nano SiO_2

以聚丙烯腈(PAN)中空纤维膜为支撑底膜,聚乙烯醇(PVA)为渗透汽化(PV)层,全氟磺酸树脂(PFSA)为催化层,催化层中填充纳米二氧化硅,制备了催化与分离双功能中空纤维复合膜。考察了该双功能膜的一系列表面性能:亲水性、对乙酸乙酯塔顶粗酯的分离性能、力学性能以及对乙酸-乙醇酯化反应的催化性能。实验结果表明:催化与分离双功能膜具有良好的力学性能和亲水性,其渗透通量可达175 g/(m2.h),相对应的分离选择性为144;相比于空白实验,双功能膜可明显提高乙酸-乙醇酯化反应的转化率,缩短达到平衡转化率的时间,其平衡转化率达60%。

Catalytic and separative difunctional hollow fiber composite membranes were prepared using polyacrylonitrile （PAN） hollow fiber membrane as support, polyvinyl alcohol （PVA） as separative layer, and perfluorosulfonic acid resin （PFSA） as catalytic layer where nano-sized SiO2 was embedded. The surface performances of difunctional membranes such as water contact angles, mechanical properties, separation performances and catalytic performances for the acetic acid-ethanol esterification were investigated. The results showed that the catalytic and separative difunctional membranes had good mechanical properties and hydrophilicity with a permeation flux of 175 g/（m2 ·h） and the corresponding selectivity of 144. Compared with blank, the conversion of acetic acid-ethanol esterification increased significantly by using difunctional membranes. The time to reach equlibrum conversion reduced, and the conversion could reach 60%.