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Abstrac t The adsorption through zeolite is an efficient way of phenol removal from water. The adsorption performance of all-silica zeolites including BEA (Beta), FAU (Faujasite), MFI (silicalite-1), and MOR (Mordenite) to adsorb phenol from phenol/water vapor mixture was predicted and compared through Grand Canonical Monte Carlo (GCMC) simulation. The results show that the adsorption of phenol on zeolites is a function of diameter of largest included sphere and largest free sphere dimensions at high loading (FAU > BEA > MFI > MOR). At low pressure, the phenol adsorption is a function of Framework Density, FD Si , as: MFI > MOR ∼ BEA > FAU due to dominant adsorbate–wall attractions compared to other interactions. The preferential siting of zeolite is suggested by both GCMC simulation and quantum mechanics approaches. Hydrogen bonding and dispersion can improve the formation of clusters of organic compounds in the intersection and middle channel of zeolite. In distribution function versus energy curve, FAU shows a clear peak at about −20 kcal mol −1 since it possesses supercages with one tetrahedral center. Our results show that both the difference between structures of the zeolites and the interactions can be taken into account to determine the adsorption capacity. [ABSTRACT FROM AUTHOR]

In this work, cationic (Mg, Ca, Sr, and Ba) substitution in X and Y faujasite zeolite structures and their effects on capacity of zeolites for methane adsorption were studied by applying multiple linear regression and expert adaptive neuro-fuzzy inference system (ANFIS) . Temperature, pressure, and molecular weight of cations were used as the input parameters. The results obtained from application of the proposed ANFIS model showed that at high pressures, the zeolite with smaller cation in their structure have higher methane adsorption capacity. The root-mean-square error, square correlation coefficient ( R ), mean absolute error, and percentage of mean absolute relative error for X and Y faujasite zeolites were evaluated, which indicated that ANFIS model can accurately predict the adsorption of methane gas on X and Y zeolites in the presence of the substituted cations. [ABSTRACT FROM AUTHOR]

Highlights: [•] The adsorption and separation properties of new siliceous zeolites were investigated. [•] The force fields of COMPASS, PCFF, CVFF, DREIDING and Universal were used in the GCMC. [•] The PCFF is the best force field for simulation of adsorption in zeolites. [•] RWY zeolite is the best zeolite types for the separation of binary mixture. [Copyright &y& Elsevier]

The adsorption isotherm of hydrogen in zeolites FAU, LTA, KFI, RWY, RHO and TSC has been simulated employing grand canonical Monte Carlo procedure for a temperature range of 77 to 95 K and different pressures. The effects of structural composition, unit cell volume, framework density and specific surface area of zeolite on hydrogen adsorption in zeolites were investigated. The results clearly show that the adsorption of hydrogen in zeolites with the same silica density is a function of oxygen density at low pressures, and it is approximately the same at intermediate pressures. Nevertheless, at high pressures, the adsorption of hydrogen is a function of pore diameter for zeolites with same silica density. The effect of specific surface area on the adsorption isotherm of hydrogen on zeolites with approximately the same specific surface area is significant at low and high pressures. The results clearly indicate that the adsorption of hydrogen in RWY zeolite has maximum value at 77 K and at high pressures. The optimum condition of pressure for hydrogen adsorption isotherm in RWY zeolite is determined to be 600 bar. At a temperature of 77 K and a pressure of 600 bar, the adsorption of hydrogen in RWY zeolite is 6.93 wt %. [ABSTRACT FROM AUTHOR]

Abstract: Grand Canonical Monte Carlo simulation is used to study adsorption of nitrogen on new type of zeolites such as IHW, IWV, SIV, UFI, and MSE at temperature range 273–325K and pressures up to 50bars. The optimum parameters of Lennard–Jones potential are evaluated and their effects on the simulation results are examined. Besides, the effects of temperature, pressure, framework density (FD) and oxygen density in unit cell on the adsorption isotherms are investigated. Although, the adsorption of nitrogen is a complex function of pressure, temperature, and pore structure of zeolite, it is found that, at room temperature, the adsorption increases linearly with increasing pressure. The results show that IWV type of zeolite gives the greatest adsorption at sufficiently high pressure. At low pressure, the effect of oxygen density in simulation box on the adsorption isotherms is higher than pore diameter. At high pressure, the effect of temperature on the adsorption isotherm does not depend on structural composition of zeolites. [Copyright &y& Elsevier]

Abstract: Zeolites belong to a most prominent class of nanoporous materials which have been considered as potential sorbents for hydrogen storage. The adsorption of hydrogen molecules on purely siliceous zeolites such as ACO, MEP, ASV, ANA, RWY, and RHO, which encompass a range of different pore structures and their chemical compositions has been simulated employing Grand Canonical Monte Carlo (GCMC) procedure for a temperature range of 250–325K, and a pressure range of 0–10kbar. The effects of pore structure of zeolites, temperature and pressure on the hydrogen adsorption has been examined. The results clearly show that the number of adsorbed hydrogen molecules at high pressure, only depends on pore diameter, and the temperature effect on the adsorption decreases with decrease in the number of adsorbed of hydrogen molecules. [Copyright &y& Elsevier]