Preparation and pervaporation performance of high-quality silicalite-1 membranes

High-performance silicalite-1 membranes were successfully synthesized on novel porous silica tubes by two-step in-situ hydrothermal synthesis.The flux and separation factor towards ethanol/water mix- ture at 60℃were 0.56 kg/(m2·h)and 84,respectively.The as-synthesized silicalite-1 membranes were characterized by scanning electron microscopy(SEM).The influence of different synthesis conditions on the separation performance of the silicalite-1 membranes was investigated.It was found that the average flux of silicalite-1 membranes was improved by about 26%after filling the silica tubes with mixed solution containing glycerol and water.After calcinating at 400℃for 5 h repeatedly,membrane synthesized on silica tube still showed high pervaporation performance towards ethanol/water mixture even at a calcination rate of 4℃/min,which suggested that silica support was more suitable for pre- paring high-performance silicalite-1 membranes.

High-performance silicalite-1 membranes were successfully synthesized on novel porous silica tubes by two-step in-situ hydrothermal synthesis. The flux and separation factor towards ethanol/water mixture at 60°C were 0.56 kg/(m2·h) and 84, respectively. The as-synthesized silicalite-1 membranes were characterized by scanning electron microscopy (SEM). The influence of different synthesis conditions on the separation performance of the silicalite-1 membranes was investigated. It was found that the average flux of silicalite-1 membranes was improved by about 26% after filling the silica tubes with mixed solution containing glycerol and water. After calcinating at 400°C for 5 h repeatedly, membrane synthesized on silica tube still showed high pervaporation performance towards ethanol/water mixture even at a calcination rate of 4°C/min, which suggested that silica support was more suitable for preparing high-performance silicalite-1 membranes.