Dealuminated L-zeolite(s) production

摘要

Production of dealuminated L-zeolites comprises treating with silicon tetrachloride (SiCl4). The zeolites used are previously converted into the sodium form by ion exchange. Also claimed are dealuminated L-zeolites having a symmetrical T-O valence swing measured by infra-red spectroscopy with a wave number of more than 785 cm<-1>. The double swing has a wave number of more than 612 cm<-1>.