Zeolite (NaX, NaX-CeO2) and mixed oxide (Co4MnAl, NiMgMn) catalysts were tested in catalytic oxidation of volatile organic compounds (VOCs). The different kinds of catalysts proved remarkable activity in catalytic oxidation of ethanol and isopropanol respectively. The deepen comparison revealed that basic zeolite NaX-CeO2 is more suitable for oxidation of isopropanol while oxidation of ethanol ...

The results of X-band EPR, X-ray absorption and Fourier transform infrared spectroscopy on Pt(NH(3))(4)(2+) exchanged NaX, NaY and NaA zeolites reveal after oxygen calcination at 573 K that diamagnetic Pt(2+) is not the only product. Calcination provides Pt(3+) cations, but depending on the heating rate, the decomposition of amino groups during calcination also produces hydrogen that reduces Pt...

In the present work, the nano-NaX zeolite and micro-NaX zeolite were synthesized via hydrothermal method. Then, the adsorption capacities and isotherms of pure gases CO2 and CH4 on the synthesized zeolite nanoparticles were determined at three temperatures of 288, 298 and 308 K and various pressures from 1 up to 20 bar. Adsorption capacities of CO2 on the nano-sized zeolites NaX were showed to ...

A series of experiments were designed to utilize the Taguchi method for investigating the effects of important parameters on the synthesis of NaX zeolite and to find the best conditions of synthesis. An L9 orthogonal design of Taguchi approach was applied to design experiments consisting of 9 trails. The effect of molar composition, including SiO2/Al2O3 and Na2O/Al2O3 ratios, and the crystalliz...

The effects of varying the silica source on synthesis of NaX zeolite crystals via conventional hydrothermal method have been investigated. Five different silica sources were selected while other parameters like Al source, reaction and aging time, SiO2/Al2O3 molar ratio and temperature were same. The prepared products were characterized by XRD technique. The results showed that different cry...

a series of experiments were designed to utilize the taguchi method for investigating the effects of important parameters on the synthesis of nax zeolite and to find the best conditions of synthesis. an l9 orthogonal design of taguchi approach was applied to design experiments consisting of 9 trails. the effect of molar composition, including sio2/al2o3 and na2o/al2o3 ratios, and the crystalliz...

The ion exchange of Na for Cr/K, Cr/Mg and Cr/Ca in Y and X zeolites was studied using breakthrough curves. It was observed that Cr ions were able to remove some competitive ions that had already been exchanged at the zeolitic sites, producing a sequential ion exchange. Some mass transfer parameters such as length of unused bed, overall mass transfer coefficient, operational ratio and dimension...

We review recent applications of jump models for diffusion in zeolites. We describe the results of a coarse-grained model of the interplay between zeolite anisotropy and disorder, finding that certain disorder patterns can change how anisotropy controls membrane permeation. We show the results of a lattice model for single-file diffusion in zeolite membranes, demonstrating how single-file motio...

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 o...

Due to the neurotoxicity of organophosphate (OP) pesticides and nerve agents synthesized as military or terror agents, their safe destruction and disposal is of considerable current importance. A representative OP, trimethyl phosphate (TMP), was adsorbed onto NaX zeolite, two mesoporous modifications, and a low-silica X zeolite. The nucleophilic chemical reactions of TMP with the zeolites were ...