the aim of this research is studying the effects of ge-doped on co adsorption on the outer and inner surfaces of (6, 0) zigzag model of boron nitride nanotube (bnnts) by using dft theory. for this purpose, eight models of co adsorption on the surfaces of bnnts are considered. at first step, all structures were optimized at b3lyp and 6-31g (d) standard base set and then the electronic structure,...

in the paper we developed a new method to determine the absolute amount of adsorption. this method relies on the excess adsorption isotherm and the density profile in the pore of one material. to compute the density profile and decrease complex calculation of obtaining the absolute amount of adsorption we introduced simplified local-density (sld) model. a few of appropriate parameters were acqu...

The potential of spherical lignin beads as an adsorbent to take up Llysine from aqueous solution was investigated. The kinetic data were estimated by the pseudo-first-order and pseudo-second-order models. The mechanism of adsorption was also studied using the Boyd model and Webber’s intraparticle diffusion model. The equilibrium data were modeled by the Langmuir, Freundlich, and Dubinin-Radushk...

Some nanoporous, crystalline materials possess dynamic constituents, for example, rotatable moieties. These moieties can undergo a conformation change in response to the adsorption of guest molecules, which qualitatively impacts adsorption behavior. We pose and solve a statistical mechanical model of gas adsorption in a porous crystal whose cages share a common ligand that can adopt two distinc...

Activated carbon derived from biomass waste, namely palm shell, was evaluated as a potential adsorbent for the removal of Reactive Black 5 dye (RB5) from an aqueous solution. This work focused on the equilibrium isotherms and the kinetics of the adsorption process. Batch adsorption tests were conducted to determine the effects of various parameters, such as contact time, RB5 concentration, adso...

This study investigated the power of hydroxyapatite adsorbent prepared by a combined precipitation-microwave method, for removing a cationic dye methylene blue in aqueous media. The used adsorbent was characterized by X-ray diffraction (XRD) and infrared spectroscopy (IR). The adsorption tests were conducted in batch mode. The effect of temperature, the pH of the solution and the mass of the ad...

The occurrence of contaminants in wastewaters, and their behavior during wastewater treatment and production of drinking water are key issues to re-use water resources. The present research aims to remove caffeine from aqueous solutions via adsorption technique, using Multi-Wall Carbon Nanotubes (MWCNTs) as an adsorbent under different experimental conditions. The processing variables such as p...

Adsorption on heterogeneous surfaces with three basic energy distribution models (uniform model, exponential model, and normal-like model) is studied. Exact analytical solutions of the adsorption isotherms and the heats of adsorption are derived for the uniform and exponential models, and, with these solutions including a numerical solution for the normal-like model, the behavior of the differe...

In this study, removal of Acid blue 62 from aqueous solution by mesoporous silicate MCM-41 modified by Aminopropyltriethoxysilane (APTES) composite was studied. Properties of synthesized composite were analyzed and confirmed by SEM, EDX and FTIR. Results show that Langmuir adsorption isotherm has the best compatibility with the results of experiments. Kinetic analysis using pseudo-first-order m...