this paper presents a systematic study of the surface chemistry, porous texture and adsorptive characteristics of prepared new activated carbon using persian mesquite grain. several techniques and methodologies such as, proximate analysis, n2 adsorption–desorption isotherms, scanning electron microscope (sem), fourier transform infrared spectroscopy(ft-ir), x-ray diffraction (xrd), x-ray photoe...

A model of the capillary condensation process, i.e., of adsorption-desorption isotherms, having only porepore interactions is constructed. The model yields ~1! hysteretic isotherms, ~2! invasion percolation on desorption, and ~3! hysteresis with discrete memory for interior chemical potential loops. All of these features are seen in experiment. The model is compared to a model with no pore-pore...

plants uptake boron (b) from the soil solution, in which boron concentration is controlled by adsorption and desorption reactions on soil organic and inorganic colloids. considering the importance of aluminosilicate minerals in ion adsorption and desorption reactions in soil, in this research, b adsorption behavior on kaolinite was studied as a function of equilibrium concentration, ph, kaolini...

Isotherms for the adsorption of KCl in PVOH-borate hydrogel was studied at 303 K by determining the amount of potassium and chloride ions adsorbed in PVOH-borate hydrogel using ion exchange chromatography and potentiometric titrations respectively. Experimental data was tested for Frendulich’s, Langmuir’s, Temkin’s and Dubinin–Radushkevich isotherms equations. The adsorption data follows isothe...

The recently developed density functional theory method for pore size distribution analysis from nitrogen adsorption and desorption isotherms is extended to materials with pores ranging from 2 to 100 nm. The method is based on the nonlocal density functional theory (NLDFT) of capillary condensation hysteresis in cylindrical pores. It is shown that NLDFT correctly predicts both the adsorption an...

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...

Fully dehydrated and partially sodium-cesium containing RHO zeolite (Na,Cs-RHO) shows a genuine inflection in the CO2 isotherms in the temperature range 293-333 K that can be attributed to a sorbate-induced framework deformation from an acentric (A) to a centric (C) phase due to a partial cation rearrangement. This peculiar sorption pattern can be captured by the formulation of thermodynamic is...

the adsorption and desorption properties of sqd-85 resin for cu(ii) had been investigated. a series of experiments were conducted in a batch system to assess the effect of the system variables, i.e. initial ph, contact time and temperature. the results show that the optimal ph for the adsorption was 5.99 in the hac-naac system, and the maximum adsorption capacity was estimated to 324 mg/g at 29...

Adsorption and desorption of atrazine and its metabolites in vegetated filter strip soil (VFS) has not been evaluated, yet these data are needed to predict the transport of these compounds through the VFS. Adsorption and desorption parameters for atrazine, desethylatrazine (DEA), deisopropylatrazine (DIA), and hydroxyatrazine (HA) were compared between a cultivated Houston Black clay (CS) and a...

in the present study seven synthetic polymers were used as adsorbents for the removal of cd(ii) from aqueous solution. the equilibrium studies were systematically carried out in a batch process, covering various process parameters that include agitation time, adsorbent dosage, and ph of the aqueous solution. the analyzing system was an atomic absorption spectrometer (perkin-analyst 100). it was...