Carbon-Zeolite NaA Composite Membranes

Zeolites are crystalline microporous materials with well-defined and uniform pore structure that find extensive industrial uses as adsorbents, catalysts and ion exchangers [1-2]. Zeolite films supported on different materials have been successfully prepared and have potential applications as highly selective membrane separators, membrane reactors, chemical sensor and microdevices [3-10]. Most of the early work focused on zeolite membranes grown on polymers and ceramics as supports. Porous carbon materials are promising candidates as supports because of their high internal surface area, porosity and excellent stability in a non-oxidising atmosphere. Zeolite films grown on porous carbon supports can modify the nature of the carbon materials themselves and present different other types of potential advantages in a number of applications. On the other hand, by being grown with a layer of zeolite, the pores of porous carbon materials can be narrowed to a desired uniform subnanometer size, which is one of the most difficult but fascinating tasks that carbon researchers have to attempt [11]. This may open up a novel approach to tune the pore structure of porous carbon materials at a subnanometer level by changing the size or the shape. This work investigates the preparation of zeolite NaA membranes on porous carbon tubes.