Growth process and short chain alcohol separation performance of fluoride-containing NaY zeolite membrane

Growth process of the NaY zeolite membranes was investigated by fluoride-containing precursor synthesis gel. Compared with the fluoride-free precursor synthesis gel, the irregular NaY zeolite crystals were dissolved into amorphous by the fluoride-containing precursor synthesis gel initially, the amorphous contained the Y-type zeolite characteristic bands by the IR characterization. The fine square NaY zeolite crystals arose from the amorphous, which were accumulated and gradually grew into a dense NaY zeolite layer on the support surface after 6.5 h. Because the excessive NaY zeolites were dissolved by the strong alkaline and fluoride-containing precursor synthesis gel, there was plenty of amorphous on NaY zeolites layer for prolonging the crystallization time. The as-synthesized NaY zeolite membranes had a good separation performance and repeatability for separation of 10 wt% methanol (MeOH)/methyl methacrylate (MMA) mixture by pervaporation, the flux and separation factor were (1.27 +/- 0.07) kg.m(-2).h(-1) and (4900 +/- 1500) at 323 K, respectively. Besides, the NaY zeolite membranes were applied to separate the other short chain alcohol from the various alcohol/organic ester and alcohol/organic ether mixtures, the NaY zeolite membranes showed high short chain alcohol perm-selectivity. (C) 2020 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

The growth of NaY zeolite membranes using fluoride-containing precursor synthesis gel resulted in the formation of fine square crystals on the support surface after 6.5 hours. The excess NaY zeolites were dissolved by the gel, prolonging the crystallization time and enhancing membrane performance. The resulting NaY zeolite membranes showed high perm-selectivity for short chain alcohols in various alcohol/organic ester and alcohol/organic ether mixtures.