Modeling adsorption of hexavalent chromium using a low-cost Jordanian olive stone waste adsorbent

Olive stone waste (OSW) manifests as one of materials generated in Mediterranean countries. In Jordan produced thousands of tons of this natural waste. For removing the Cr(VI) ions from industrial liquid solutions, olive stone waste was employed as a natural adsorbent. The optimal conditions for removal processes were determined by sets of experiments. The contact time was 360 minutes, pH was 2.7, the adsorbent dosage was 4 g /L and the temperature was 25 degrees C. Results of adsorption mechanism data analysis for different Cr(VI) initial concentrations of 0.3, 2.7, 4.5, 9, 18 and 60 mg/l removed by OSW adsorbent fitted the Freundlich adsorption isotherm R-2 = 1, and near very close to pseudo second-order kinetics also R-2 = 0.998. It was found that the adsorption of Cr(VI) depended on concentration. Hexavalent chromium can be effectively removed from liquid industrial wastewater using olive stone waste.