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Seawater desalination is primarily conducted using multistage flash (MSF) distillation and reverse osmosis (RO). During the last decade, desalination studies using pervaporation with zeolite membranes began to receive considerable attention [1]. Therefore, zeolite membranes will play an important role in seawater desalination using pervaporation.In the last decades, zeolite membranes have attracted considerable research attention because of their potential applications, such as separation membranes, catalytic membrane reactors, and chemical sensors [1-6]. Because zeolite membranes are required to have sufficient mechanical strength without macroscopic defects to be used as a separation filter, two types of zeolite membranes can be considered: (1) thick zeolite polycrystalline films (self-supported) and (2) thin zeolite films supported by some porous materials (e.g., alumina, silica, and stainless steel) [7-8]. However, few self-supporting zeolite membranes have been reported, and their separation performances have not been intensively studied [9]. In general, the preparation of self-supported zeolite membranes introduces some drawbacks related to the dimensions, the lack of homogeneous thickness, and the mechanical stability of the membrane. Usually, self-supporting zeolites membranes are composed of packed zeolite particles with interzeolitic pores (that are non-zeolitic pores) [9]. However, the self-supported zeolite layers lack strength and are highly fragile. Therefore, zeolite-layer membranes with permanent supports are more common than self-supporting membranes. For example, the growth of zeolites on porous supports, such as alumina and stainless steel, generally results in a random orientation of crystals due to the roughness of the applied supports [1-7, 10-13]. |