investigation of the use of various silica source on nax zeolite properties

silicon and aluminum sources are most important reactants in the synthesis of zeolite. the use of the silicon source has an important effect on the crystallization of zeolites. also, it can change the properties of the end product. this work reports the influence of three common commercial silica sources such as colloidal silica (ludox am-30), fumed silica and water glass on the crystallinity of nax zeolite by hydrothermal method, also the adsorption of carbon dioxide on these samples have also been studied. the synthesized samples from different sources are characterized by x-ray diffraction (xrd), scanning electron microscope (sem), fourier transformin frared (ft-ir) and nitrogen adsorption–desorption analysis. the sample obtained by fumed silica, colloidal silica and water glass is nax phase. the percentage of crystallinity and surface area increased in the sequence: water glass< colloidal silica < fumed silica, also the sample of synthesized by fumed silica (z-f) with higher crystallinity, shows better performance in the adsorption process.