Equilibrium and Kinetic Study on the Abolition of Hexavalent Chromium from Aqueous Solutions Utilizing Xanthated Tea Waste

Abstract Heavy metal removal is critically necessary to prevent water pollution. At various initial hexavalent chromium concentrations, adsorbent dosages, pHs, and contact periods, the removal of hexavalent chromium from aqueous solutions onto Xanthated Tea Waste was investigated. FTIR and XRD techniques were used to characterize the adsorbent. Hexavalent chromium was initially removed from aqueous solutions with an increase in adsorbent dosage and contact time, but it was shown that the adsorption of Cr (VI) was best at a contact period of 120 min and an adsorbent dose of 100 mg/L. In a similar manner, the amount of hexavalent chromium eliminated from the aqueous solutions increased as the hexavalent chromium concentration grew and decreased as the solution's pH increased, with pH 2.0 being the ideal. Using a pseudo second-order model, the kinetics of hexavalent chromium adsorption onto modified tea trash was studied. The adsorption equilibrium data were modeled using Langmuir isotherm models. The equilibrium results for the elimination of hexavalent chromium by modified tea trash were well represented by the Langmuir isotherm model. According to the isotherm analysis, the adsorption equilibrium fit the Langmuir isotherm well. At pH 2.0, the obtained maximum adsorption capacity was around 82%. According to the findings, chromium-containing aqueous solutions can be treated using Xanthated Tea Waste as a low-cost adsorbent.