جستجوی مقالات مرتبط با کلیدواژه "sorption" در نشریات گروه "شیمی"

This research work aims to investigate the sorption of nickel ions from an aqueous solution using Activated Carbon modified by Sodium Dodecyl Sulfate (AC-SDS). The sorption process by the batch method is carried out. The characterization of the adsorbent structure was studied by FT-IR, SEM, and BET. The effect of pH, contact time, initial concentration, and temperature were investigated. The optimum condition of nickel sorption onto AC-SDS was found to be: a sorbent dose of 1 g in 100 ml of nickel ions, contact time of 300 min, pH=8, in optimum condition removal efficiency was 95.18% for nickel. Three equations, i.e. Morris Weber, Pseudo first order, and pseudo-second-order have been tested to track the kinetics of the removal process. The Langmuir, Freundlich, and R-P are subjected to sorption data to estimate sorption capacity. It can be concluded that AC-SDS has the potential to remove nickel ions from an aqueous solution at different concentrations. In addition, the effect of temperature on the process was investigated. It was found that the temperature has a positive effect on the process and the negative ΔG values indicated the thermodynamically feasible and spontaneous nature of the sorption. The positive value of ΔS reveals the increased randomness at the solid–solution interface during the fixation of the ion on the surface of the sorbent.

Magnetic core-zeolitic shell structures modified with 3-Glycidyloxypropyl-trimethoxysilane (GPTMS) organic agents prepared by the hydrothermal method. The samples were characterized by X-Ray Diffraction (XRD), Thermo Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), and nitrogen adsorption-desorption isotherms (BET). The results of the XRD patterns confirmed the successful growth of aluminosilicate crystals on the surface of the magnetic cores. Furthermore, the SEM images indicated that structures were spherical and the particle size was below 100 nm. The sorption activity of the samples was evaluated by removal of lead and cadmium ions from the wastewaters and according to the results, the final sorbent was enabled to decrease the concentration of cadmium ions selectively. The sorption routes and the effect of the presence of organic agents on the sorption efficiency were mechanistically discussed. The effect of the acidity of the medium on the sorption capacity of the prepared structures was studied and the obtained results were discussed in terms of the chemical structure of the surface.