Layer-by-Layer Assembly of Zeolite/Polyelectrolyte Nanocomposite Membranes with High Zeolite Loading

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• 作者：Yan Kang ; Laleh Emdadi ; Michael J. Lee ; Dongxia Liu ; Baoxia Mi
• 刊名：Environmental Science & Technology Letters
• 出版年：2014
• 出版时间：December 9, 2014
• 年：2014
• 卷：1
• 期：12
• 页码：504-509
• 全文大小：392K

文摘

Incorporation of zeolite nanoparticles into nanocomposite membranes is advantageous with respect to enhancing membrane permeability by providing preferential water flow paths through the subnanometer porous structure of zeolite while maintaining excellent separation capability. We present a layer-by-layer assembly approach to effectively incorporate zeolite nanoparticles into nanocomposite membranes. Negatively charged Linde type A (LTA) zeolite nanoparticles were sandwiched between two different polyelectrolyte layers, negatively charged poly(acrylic acid) (PAA) and positively charged polyethylenimine (PEI), to form a PEI鈥揕TA鈥揚AA trilayer. The zeolite loading in the multitrilayer membranes was between 30 and 60 wt %, which is attributed to the drastically improved compatibility between zeolite and polymers, a direct result of electrostatic interactions. The performance of the trilayer membrane was compared with that of a control PEI鈥揚AA bilayer membrane in a forward osmosis membrane system. The incorporation of zeolite nanoparticles was found to enhance membrane water permeability by >2-fold without compromising the membrane selectivity for tested species.