Adsorptive remediation of hexavalent chromium using agro-waste rice husk: Optimization of process parameters and functional groups characterization using FTIR analysis

Abstract

Hexavalent chromium [Cr (VI)] is considered as a toxic heavy metal in water bodies, posing global environmental and health risks. It has various detrimental impacts on the environment and human beings. The remediation of such toxicants from polluted sites has become essential for the good health of our ecosystem. Adsorption is a sustainable and eco-friendly solution for the efficient removal of such toxic heavy metals. In this study, the potential of an agro-waste material like rice husk (adsorbent) was investigated for remediation of the Cr(VI), and various parameters affecting the adsorption process were optimized to obtain the optimal conditions for effective remediation. By utilizing rice husk, the maximum 96.5% of Cr(VI) remediation efficiency was observed at an initial Cr(VI) level of 100 mg/L, pH 2, temperature 40oC with an adsorbent dosage of 26 g/L. The fourier transform infrared (FTIR) spectroscopy of rice husk with and without Cr (VI) indicated the functional group involvement in the metal adsorption. This study highlights the potential of agricultural waste, rice husk as an effective adsorbent material that may possibly employed in the remediation of Cr (VI) at a larger level.