负载金属离子ZSM-5分子筛膜脱除噻吩的性能

以四丙基氢氧化铵、四乙氧基硅烷和去离子水为原料,采用一次水热合成法,制得了 ZSM-5分子筛膜;采用 X 射线衍射和扫描电子显微镜对膜的物理及化学结构进行了分析和表征。将 ZSM-5分子筛膜用于正己烷中噻吩的脱除,研究了负载金属离子种类、负载 Ag~+浓度、料液温度和焙烧温度对膜性能的影响,并考察了膜的再生效果。实验结果表明,负载 Ag~+的 ZSM-5分子筛膜对噻吩的脱除效果最佳,噻吩的脱除效果随负载 Ag~+浓度的增加而提高;升高料液温度,渗透通量增加,负载 Ag~+的ZSM-5分子筛膜对噻吩的选择性下降;未经焙烧的负载 Ag~+的 ZSM-5分子筛膜的脱硫性能比经焙烧的负载 Ag~+的 ZSM-5分子筛膜的脱硫性能低。从脱硫效果和再生效果看,只需简单焙烧即可恢复 ZSM-5分子筛膜的脱硫性能,且操作简单。

Thiophene Removal Activity of ZSM-5 Zeolite Membrane Loaded with Metallic Ions

ZSM-5 zeolite membranes were prepared by single-step in situ hydrothermal synthesis on surfaces of α-Al_2O_3 tubes in tetrapropylammonium hydro xide-tetraethoxy silicone-deionized H_2O system.Characteristic structures of membranes were analyzed by means of XRD and SEM.Thiophene was removed from n-hexane by ZSM-5 membranes.Effects of loaded ion type,loading Ag~+solution concentration,feed solution temperature and calcination temperature on membrane activity were studied. Regeneration of membrane was examined.Thiophene removal activity was the best when ZSM-5 membranes were loaded with Ag~+and was improved with increasing of loading Ag~+solution concentration.Raising feed solution temperature favored permeation flux but decreased the selectivity of thiophene removal.Calcination of membrane loaded with Ag~+was advantageous to removal of thiophene.The used ZSM-5 membranes after thiophene removal can be recovered by simple calcination.