Abstract
We have successfully investigated nitrogen adsorption measurement using ZSM–5 type zeolite membrane prepared by seed assisted hydrothermal synthesis with various crystallization periods under non–destructive condition. Micro– and meso–pores derived from zeolitic and non–zeolitic structures were analyzed using nitrogen adsorption isotherm with the Saito–Foley model and the Kelvin equation. ZSM–5 membranes synthesized for various crystallization periods were characterized and evaluated by SEM, XRD, nanopermporometry and permeation tests. In this study, it could be considered that ZSM–5 membrane formation process had two–step as follows. First, ZSM–5 seed crystal was grown up in/onα–alumina support, and ZSM–5 micro–crystals generated in pore ofα–alumina support until 6 hours synthesis. After that, ZSM–5 crystals on theα–alumina support surface were predominantly grown up, and these crystals covered the support surface. After synthesis of 12 hours, the membrane had hardly defects.
