Nanoalumina-supported Mn2O3 as efficient adsorbent for removal of fluoride and arsenic from water: a study from lab to field

摘要

Water pollution with heavy metals has been a problem for the environment and human health. The cohabitation of As(III) and fluoride in groundwater has gotten attention worldwide, and it is critical to get rid of them quickly. In this study, nano-gamma Al-Mn-O was synthesized via precipitation method based on a simple and economical route. A series of batch experiments were conducted to examine the effects of contact time, adsorbent dose, and pH and initial concentration on adsorbent removal capacity. The mechanism of fluoride and As(III) uptake by Al-Mn-O and Al2O3 is due to physical adsorption and intraparticle diffusion, which was confirmed by kinetics, isotherm, zeta potential measurements, and XPS. The impact of manganese oxide coating on gamma alumina oxide nanoparticles on fluoride and As(III) removal was compared to uncoated gamma alumina oxide. The removal capacity of fluoride on gamma Al-Mn-O and gamma-Al2O3 is 53% and 23%, respectively. As(III) removal capacity is 40% and 30%, respectively, on alumina-manganese oxide and alumina oxide. The synthesized sample was found equally effective in removing fluoride from the fluoride contaminated water collected from the Dhar district of Madhya Pradesh in India, one of the most fluoride-affected region in Asia.