Removal of hexavalent Cr (VI) from aqueous solution by Agricultural Waste

Agricultural wastes are affordable adsorbents for the removal of heavy metals from aqueous solutions. Chromium is considered as one of the important environmental pollutants due to its toxicity considered as water contaminant that may disturb metabolic activity. This study explores the potential of Saffron petals powder and Saffron petals charcoal for adsorption of Cr (VI) in aqueous solution and compression with Granular Activated Carbon (GAC). The influences of several main parameters such as pH value of solution, sorbent amount, initial metal-ion concentration, and contact time in batch experiments have been studied. The adsorption was solution pH dependent and the maximum adsorption was observed at solution pH of 2.0. The amounts of Cr (VI) adsorbed increased with increase in dose of three adsorbents and their contact time. Maximum Cr removal efficiencies were obtained by Saffron petals powder, Saffron petals charcoal and GAC, 0.16mg/g, 65.33mg/g and 62 mg/g respectively. Adsorption isotherms were compared with both Langmuir and Freundlich adsorption models. The experimental data best fit with the Langmuir isotherm model. Experimental results show low cost biosorbent was effective for the removal of pollutants from aqueous solution

کلیدواژه ها:

Removal of Chromium ، Agricultural wastes ، Adsorption isotherms ، environmental pollutants