Synthesis and pervaporation performance of high-reproducibility silicalite-1 membranes

High-reproducibility silicalite-1 membranes were synthesized on silica tubes by in-situ hydrothermal synthesis, and the relative standard deviation (R.S.D.) of average separation factor for eight membranes was only 7.5%. By using an effective method called “solution-filling (SF)”, the average flux of membranes prepared with SF method was improved by about 49% compared to membranes prepared without SF method, and the highest flux of membrane prepared with SF method towards ethanol/H₂O mixture at 80 °C was 1.49 kg/(m²·h). Pervaporation experiments showed that the fluxes of silicalite-1 membranes at 60 °C were 2.63, 0.87, 0.24, and 0.20 kg/(m²·h) towards methanol/H₂O, ethanol/H₂O, 2-propanol/H₂O, and 1-propanol/H₂O mixtures, respectively, and the corresponding separation factors were 22, 69, 81, and159, respectively. Supported by the National Advanced Materials Committee of China (Grant No. 2003AA328010) and the Ministry of Science and Technology of China (Grant No. G2003CB615802)