Molecular transport through the nanoporous particles, in particular, zeolite crystallites, is influenced both by intracrystalline diffusion and surface resistance. In comparison to zeolite crystallites with ideal structure, molecular transport in real-world zeolite particles may often be influenced by the surface barriers resulting from various defects at the surface of the crystallite. The pot...

This study evaluated the applicability of natural zeolite for the removal of the NH-forms in the enzyme-mediated calcite precipitation technique. The natural zeolite of mordenite was added to prepared grouting solutions composed of urea and urease and mixed thoroughly using a rotation table for the mixing times of 0.5, 1.0, and 2.0 h. Then, the concentrations of evolving NH-forms in the solutio...

1. Introduction Zeolites have gained an irreplaceable role as catalysts in the refining industry. With a production capacity of 625·10 6 t in 2004, the fluid catalytic cracking process (FCC) represents the second most important heterogeneously catalyzed process [1]. As an active component, the catalyst of this process contains zeolite H-Y. Since a high-molecular feed is used, a detailed knowled...

Using reactive molecular dynamics (RMD), we present an atomistic insight into the interaction between water molecules and acidic centers of H-ZSM-5 zeolite. The reactive force field method, ReaxFF, was used to evaluate the adsorption and diffusion of water as well as to study the protonation of water molecules inside zeolite channels. The existing Si/Al/O/H parameters were refitted against DFT ...

The decontamination reactions of O,S-diethyl methyl phosphonothiolate, as an agricultural organophosphorous pesticide onto 20 wt% loaded manganese dioxide nanoparticles-silver-Y zeolite as a nanocomposite catalyst in different solvents, were evaluated and monitored by means of gas chromatography–flame ionization detector and gas chromatography–mass spectrometry. Prior to the reaction, the catal...

The use of zeolites for the adsorption of harmful gases has widened [1, 2]. In [2] we have studied the ionic states, motional behavior and binding degrees of SO2 and CO2 reacted with type 5A (CaA) zeolite, and we have concluded that SO2 is adsorbed on the surfaces while CO2 is absorbed in the deep pores of this zeolite. In the present work the binding states of CO2 on the same zeolite was inves...