Adsorptive degradation of hexavalent chromium from aqueous solution using coconut shell as a green adsorbent

The present study aimed to remove the heavy metal compounds present in wastewater. In this study, we used hexavalent chromium Cr (VI) as a heavy metal compound, and coconut shell was used as a promising green bio-sorbent to remove Cr (VI) from wastewater. Coconut shells are readily available and are termed as waste materials. Various parameters such as contact time, pH of the solution, initial Cr (VI) concentration, and amount of coconut shell were studied. The adsorption data were fitted with various isotherm models. The Langmuir and Freundlich isotherm models were the best fit for the experimental data, and the maximum adsorption capacity was found to be 16.39 and 12.19 mg/g, respectively. Kinetic and thermodynamic studies were performed to assess the feasibility of the process. The pseudo-second-order kinetic model is also signified that the Cr (VI) adsorbent capacity was due to particle diffusion. To identify the morphological properties of the adsorbent various analysis such as Scanning Electron microscope (SEM) and BET surface area were performed. The experimental results and rate of adsorption, and the adsorption process was found to be feasible and endothermic in nature.