In this work we have analyzed the adsorption-desorption kinetics in the framework of the lattice gas model. We have shown that the coefficients representing the transition probabilities must be carefully chosen even when they fulfill the principle of detailed balance, otherwise the observables arising from the kinetics present anomalous behavior. We have demonstrated that when the adsorption Ai...

The adsorption/desorption processes of oxygen are investigated in nanoporous carbon (activated carbon fiber (ACF)) consisting of a disordered network of nanographene sheets. The heat-induced desorption at 200 °C shows the decomposition of oxygen-including functional groups weakly bonded to nanographene edges. The removal of these oxygen-including negatively charged functional groups brings abou...

In this work, we report a new hybrid nanomaterial based on the immobilization of 4-formyl benzo-9-crown-3 ether (FB9C3) onto the mesopores of MCM-41. First, the mesoporous molecular sieve MCM-41 was covalently grafted with 3-aminopropyl triethoxysilane to give aminopropyl modified MCM-41 (AmpMCM-41). Reaction of this material with FB9C3 afforded the B9C3-AmpMCM-41 hybrid nanomaterial. The prepa...

Rice straw/magnetic nanocomposites (RS/Fe3O4-NCs) were prepared via co-precipitation method for removal of Pb(II) and Cu(II) from aqueous solutions. Response surface methodology (RSM) was utilized to find the optimum conditions for removal of ions. The effects of three independent variables including initial ion concentration, removal time, and adsorbent dosage were investigated on the maximum ...

The aim of the present work is to prepare an adsorption package to simulate adsorption / desorption operation for both single and multi-component systems in an isothermal condition by different mechanisms such as; local adsorption theory and mass transfer resistance (rigorous and approximated methods). Different mass transfer resistance mechanisms of pore, solid and bidispersed diffusion, t...

The adhesion of granulocytes to a glass surface is both theoretically and experimentally investigated. The basic results are: (i) The adherence process of cells to a surface can be described by the Langmuir adsorption isotherm which also holds for the adsorption of molecules to a substrate. (ii) The granulocytes do not interact with each other during the adsorption/desorption process. (iii) The...

The desorption of methanol and dimethyl ether has been studied over fresh and hydrocarbon-occluded ZSM-5 catalysts with Si/Al ratios of 25, 36 and 135 using a temporal analysis of products reactor. The catalysts were characterized by XRD, SEM, N2 physisorption and pyridine FT-IR. The crystal size increases with Si/Al ratio from 0.10 to 0.78 μm. The kinetic parameters were obtained using the Red...

the performance of msu-s and its forms modified with phosphotungstic acid (hpw) and nickel (ni) for the desulfurization and denitrogenation of model diesel fuel were studied. according to the results of the characteristic tests (n2 adsorption-desorption, xrd, sem, and nh3-tpd), heteropoly acid incorporation causes higher acidity along with a negligible loss of structural aspects, while ni impre...

Ustiloxins are cyclopeptide mycotoxins produced by Villosiclava virens, the pathogenic fungus of rice false smut disease. Both resins SP207 and SP700 were screened to show the best adsorption and desorption properties for ustiloxins A and B among 20 commercial macroporous resins. Dynamic adsorption and desorption tests were carried out to optimize the process parameters. The optimal conditions ...

− One among factors responsible of the instability of mass standard is the adsorption and desorption induced by the cleaning products. An optical non-contact method based on mirage effect is proposed to investigate the adsorption/desorption of cleaning solvents on the surface of mass standards at conditions close to normal temperature and pressure (NTP). A model developed for the mirage effect ...