the removal of as(iii) ions from aqueous solutions has been investigated using silica ceramic under different experimental conditions of initial arsenite concentration, adsorbent dose, temperature and ph. better removal was obtained at temperature 25âºc and ph 7.5. the adsorption data have been explained in terms of langmuir and freundlich equations. the sorption kinetics was tested for the pse...

We have measured experimental adsorption isotherms of water in zeolite LTA4A, and studied the regeneration process by performing subsequent adsorption cycles after degassing at different temperatures. We observed incomplete desorption at low temperatures, and cation rearrangement at successive adsorption cycles. We also developed a new molecular simulation force field able to reproduce experime...

A modified two-dimensional van der Waals equation model was proposed for the prediction of multicomponent gas-solid adsorption isotherms from corresponding single-component adsorption equilibrium data. The model was used to predict adsorption isotherms of CO-CO2 mixtures and CO2-N2 mixtures on Cu(I)-NaY zeolite. Experimental adsorption equilibrium data of the two systems were compared with resu...

Adsorption of Cd(2+) on two types of Egyptian soils: clay (alluvial) and sandy loam (calcareous), was studied. Effect of changing the matrix electrolyte type and concentration was used to mimic the natural soil salts. Kinetics and thermodynamic parameters of the adsorption were calculated at two different electrolyte concentrations: 0.05 N and 0.15 N. The adsorption was described by Langmuir an...

This paper describes the adsorption of heavy metal ions from aqueous solutions by oak (Quercus coccifera) sawdust modified by means of HCl treatment. Our study tested the removal of three heavy metals: Cu, Ni, and Cr. The optimum shaking speed, adsorbent mass, contact time, and pH were determined, and adsorption isotherms were obtained using concentrations of the metal ions ranging from 0.1 to ...

in the present work, we have investigated the sorption efficiency of the treated activated carbon from walnut shell(acw) towards direct red 81 (dr81) and direct blue 71 (db71) for the removal from aqueous solution. thesorption study of acw at the solid-liquid interface was investigated using kinetic, sorption isotherms, ph effectand amount of adsorbent. experimental data were analyzed by langmu...

in this paper, the adsorption of cerium on modified mesoporous aluminosilicate (with si/al mole ratio of 10) was studied. the effects of ph, contact time, initial concentration of cerium on adsorption of cerium were investigated. the adsorption capacity was high in the ph range of 4-8 and decreases with decreasing of the ph value. the langmuir and freundlich isotherms were applied to represent ...