DFT Investigations and Experimental Studies for Competitive and Adsorptive Removal of Two Cationic Dyes onto an Eco-friendly Material from Aqueous Media

Abstract

The adsorption of cationic dyes in the binary system is more important than the single system; it is a component of the study of a complex matrix. The experimental and theoretical studies were realized for the adsorption of two cationic ones, the Basic Blue 41 (BB41) and Basic Yellow 28 (BY28) onto Bombax buonopozense (BBP) adsorbent, in the single and binary system. Only the effect of pH and adsorbent dosage in both systems was studied. The electrophilicity power of dyes affects the removal efficiency. The theoretical study proves that BB41 is more electrophilic than BY28, and more interactions with surface sites in the single and binary system with a removal efficiency of 93.12 and 78.41%, respectively. A pH of 7 was found to be the best condition for both systems to have a maximum removal. Freundlich is the best selected model to describe the removal of dyes in the single and binary system, also kinetics study shows that the phenomenon follows the pseudo-second-order. Theoretical studies are in good agreement with experimental ones, and the decrease of removal efficiency of BY28 in the binary system is well explicated by the lower acceptance of electrons in the presence of BB41.