Optimization of UHMWPE/Graphene Nanocomposite Processing using Ziegler-Natta Catalytic System via Response Surface Methodology

Experimental design data for the zinc ions adsorption based on mesoporous modified chitosan using central composite design method

In the present study, new generation of silica-based mesoporous adsorbents were introduced for the removal of heavy metals with the aim of developing new adsorption technologies in water treatment. The magnetic nanoadsorbent, prepared by modification of SBA-15 with [3-(2-Aminoethylamino) propyl] trimethoxysilane (AEAPTMS)-functionalized chitosan, was applied for the removal of Zn²⁺ from aqueous solution. The synthesized Fe₂O₃@SBA-15-CS-AEAPTMS nanoadsorbent was thoroughly characterized using XRD, TEM, FTIR and BET analysis. In order to determine the optimum condition of Zn²⁺ adsorption on Fe₂O₃@SBA-15-CS-AEAPTMS (3 ml), the experiments were performed based on central composite design in a response surface methodology method. The obtained results were further studied using adsorption kinetic, isotherm and thermodynamic relations which revealed that Zn²⁺ adsorption was spontaneous and endothermic with enhanced adsorption efficiency achieved for higher contents of functional groups. In addition, according to the results, the adsorption process was best conformed to Langmuir isotherm (with R² > 0.99 and q_max = 107.21 mg g^-1) and pseudo second-order kinetic model (with R² > 0.999). The values of standard entropy (DS°) and activation energy (E_a) reduced as the initial concentration was increased and the dominant mechanism was found to be chemisorption.