Assessment of two low-cost geological materials as adsorbents for arsenic

Two easily accessible local materials, kaolin, and sediments from the reservoir of a dam, were evaluated to compare their efficiencies as adsorbents for As. The kaolin sample was composed mainly by kaolinite quartz, while contained illite, montmorrillonite quartz. Also, iron, calcium magnesium minerals present minor components. adsorption experiments performed using batch equilibrium techniques. samples chemically treated piranha solution, trimesic acid, study effects on capacity. treatment seems be good alternative improve capacity kaolin. However, intact showed higher than or On other hand, initial uptake acid only slightly positive effect arsenic sediments. Most due finest particles sediments, iron minerals, organic matter contributes scarcely uptake. influences pH, contact time, concentration, chemical treatments studied. Freundlich Dubinin-Kaganer-Radushkevich isotherm models used evaluate Maximum completed almost within five hours reaction, reaching measured sorption 137 mg/kg lower