Synthesis of Zeolite LTN-(SOD) Self-Supporting Membranes from SiO2-Rich Industrial Waste

• 作者: Josef-Christian Buhl Valeriy Petrov
• 来源期刊: 材料科学与化学工程(英文)
• 学科: 化学
• 关键词: LTN ZEOLITE SELF-SUPPORTING MEMBRANE 60℃ Synthesis Industrial WASTE FLOTATION
• 年，卷（期）: 2018,（3）
• 页码范围: 68-84
• 页数: 17页
• 分类号: O6

摘要

Synthesis of zeolite LTN (“Linde Type N”) was investigated under insertion of a SiO2-rich filtration residue (FR) from waste water cleaning of the silane production. A new synthesis procedure was therefore developed applying a flotation mechanism with the aim to grow LTN in form of thin membrane like sheets. Preparation starts with preactivation of FR by slurrying first in alkaline solution, followed by an addition of aluminate solution and citric acid. The latter was added as suitable chelating agent for the initiation of the flotation process. In the course of these experiments, we succeeded in synthesizing zeo-lite LTN with more or less zeolite SOD as byproduct in the form of a stable compact membrane-like layer at low temperature of 60℃. The crystallization was performed under isotherm static conditions in an open reaction system without addition of organic templates as structure directing agents (OSDA’s). FR was utilized as a total substitute of sodium silicate in all experiments and an expansive pre-treatment procedure like calcinations was not needed. Furthermore, membrane formation with LTN of usual synthesis needs chemically functionalized supports. In contrast self-supporting membranous LTN layers were grown for the first time in the present study.