Synthesis of NaA zeolite using PTMAOH(phenyltrimethylammoniumhydroxide): hydrothermal and microwave heating methods and comparison of their XRD patterns

Abstract

Ion exchanging is one of the characteristics of the zeolites. Zeolites have octahedral and tetrahedral holes to trap ions and molecules. They also can exchange many ions in solution because of the size of the attendant ions. As a matter of fact, the property of the ion-exchanged zeolites depends on the ligands involved in the ion exchanging solutions. Ion exchanged zeolites are used as catalyst for studying the anodic oxidation of methanol in an acidic medium to investigate their suitability for use in direct methanol fuel cells (DMFCs). Some of the zeolites that have exchanged ions are shown to have redox and catalytic properties [1-3]. As an example A. Itadani et al., have reported the preparation of copper ion exchanged ZSM-5 for calorimetric study of N2 adsorption on Cu-ZSM-5 zeolite [4]. In another study, A. Ribera et al. have reported the characterization of redox properties and application of Fe-ZSM-5 catalysts [5]. In this research we prepared silicate solutions by dissolving silica in sodium hydroxide. Aluminosilicate solutions with different Al/Si ratios were prepared by mixing appropriate quantities of sodium silicate solutions with freshly prepared sodium aluminate solutions and the NaA zeolites were made by hydrothermal method. Then, their XRD patterns and IR spectra were also considered. Obviously, those zeolites which have Al-OH and Si-OH groups can lose their protons in basic solutions. In this way zeolites can adsorb many ions with positive charge. We investigated ion exchange property of Fe3+, Cu2+, Ni2+ and Hg2+ in systems with pH equals to 2, 4, 6 and 8. We found that the aluminosilicate with Si/Al = 1, has greatest exchange capacity for all of the ions studied in this work.