Adsorption of anionic dyes onto 1,5-Diphenylcarbazide functionalized magnetic hybrid polymer: Impact of water salinity and surfactants on adsorption isotherms

Abstract

Herein, an effective hybrid adsorbent based on magnetic chitosan (MC) and magnetic glycidyl methacrylate (Mp(GMA)) was synthesized. The prepared hybrid material was functionalized by 1,5-Diphenylcarbazide (DPC), then employed for the adsorption of two anionic dyes (Coomassie brilliant blue G-250; CBB, and Eosin Y; EO) from their synthetic solutions. The as-fabricated adsorbent (MC-Mp(GMA)/DPC) was specifically investigated via FTIR, SEM-EDX, BET, TGA, and VSM analyses. The influence of several operational key factors; initial solution pH, initial dye concentration, contact time, temperature, and influence of cationic, anionic surfactant, and salinity on adsorption isotherms were investigated. The findings revealed that MC-Mp(GMA)/DPC highest adsorption capacities were recorded in the presence of cationic surfactant (0.795, 0.817 mmol g−1 for CBB and EO, respectively) and salinity hardly affects adsorption isotherms. Moreover, the adsorption process of each dye was reported to fit with the Langmuir model at all conditions, while the PSORE model well-defined their adsorption kinetics. Meanwhile, thermodynamics revealed that the separation of CBB and EO dyes was endothermic. Moreover, MC-Mp(GMA)/DPC possessed a desirable efficacy for the regeneration (e.g., 77.9% and 71.7 for CBB and EO, respectively) up to the 4th cycle, affirming its outstanding renewability. Overall, the produced MC-Mp(GMA)/DPC can potentially be offered as a promising recyclable dye scavenger for wastewater remediation.