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Schematic representation showing the adsorption interaction of AO?10 dye and Cr(VI) ions on CMX?g?P4VP copolymer.AbstractThe 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.