Highly reactive adsorbent based on carboxymethyl xanthan gum-g-poly(4-vinylpyridine) copolymer for the potential removal of Acid Orange 10 dye and Cr(VI) ions for water treatment

The removal efficiency of an anionic acid dye, Acid Orange 10 dye (AO-10), and hexavalent chromium metal Cr(VI) from an aqueous medium using carboxymethyl xanthan gum-g-poly(4-vinyl pyridine), CMX-g-P(4VP), as a novel adsorbent was studied. The influences of pH, adsorbent dose, temperature, and equilibrium time on the adsorption process were evaluated to optimize the conditions for maximum removal of the adsorbate. Both AO-10 and Cr(VI) removal were pH-dependent, with the most excellent adsorption capacity occurring at pH 2.5. AO-10 and Cr(VI) had maximum adsorption capacities of 1961 and 492 mg g(-1), respectively, considerably high. The adsorbent may be efficiently reused for five cycles, according to the desorption studies. The experimental adsorption equilibrium data were described using the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The Langmuir is judged the closest to the description of the practical. In addition, the kinetics of the adsorption process is controlled using pseudo-first-order and intraparticle diffusion kinetic models, while the thermodynamic process proved the spontaneous and exothermic nature of removing AO-10 and Cr(VI) ions. Overall, the results showed that CMX-g-P(4VP) might be a very efficient re-usable adsorbent in wastewater treatment.

Automated summary

This study investigated the removal efficiency of anionic acid dye and hexavalent chromium using CMX-g-P(4VP) as an adsorbent. The results showed that the optimal pH for adsorption was 2.5. The adsorbent exhibited high adsorption capacities for both contaminants, and could be efficiently reused for multiple cycles.