Peanut shell as adsorbent material for the removal of copper ions and fluorides

Like many other pollutants that alter the quality of water bodies, copper and fluoride represent a risk to ecosystems and people's health. To solve this problem, various adsorbent materials are used as an economical and efficient alternative in processes that seek to remove these elements from contaminated water. The process will also be environmentally friendly if the adsorbent materials are biodegradable, as with peanut shells. This project's main objective is to apply peanut shells as an adsorbent material in copper removal processes and its subsequent reuse in fluoride removal. For this, the peanut shell is first used for copper removal, and the material with adsorbed copper is dried and used again for fluoride removal. Through mathematical models, it was determined that the adsorption was carried out by a combination ofphysical and chemi-cal processes in both cases. According to the Langmuir model, the removal capacity was 31.1 mg/g for Cu2+, while for the removal of F-, it was 1.6 mg/g. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) characterize the peanut shell before and after the adsorption processes.