Marble slurry waste as a scavenger material for Cr(III) ions from aqueous medium

Abstract

AbstractThe present paper reports removal of chromium from aqueous solution using marble slurry waste material at room temperature. Optimum conditions such as concentration of Cr(III) and adsorbent, solution pH, stirring time, effect of foreign ions, and effect of temperature were studied. The adsorption of Cr(III) ion onto marble slurry is well described by Langmuir and Freundlich adsorption isotherm. The maximum Cr(III) removal was 139.92 mg of Cr(III) per gram of marble slurry as evaluated from Langmuir isotherm. Thermodynamic parameters like enthalpy, entropy, and Gibbs free energy have been found to be 30.92 kJ/mol, 118.14 J/mol K, and −4.21 kJ/mol, respectively. These parameters indicated that the process was spontaneous and endothermic in nature. It has been found that 1 g/L marble slurry is capable to remove ≈100% of Cr(III) ions in the pH range of 5–10.