Method of producing activated carbon for heavy metal removal in water

Abstract

The utility model relates to a method of producing chemically activated carbon from pili nut shells for use as sorbents in removing heavy metals from aqueous solutions. The method comprises washing, drying, crushing, acid-treating, and sonicating the biomass prior to phosphoric-acid impregnation, followed by controlled pyrolysis under nitrogen flow, oxidation using breathing-grade air, and final drying and sieving to obtain uniform activated carbon particles. The activated carbon produced through the method described in this utility model contains phosphate-enriched and oxygen-containing functional groups that enhance its affinity toward nickel and chromium ions. The method also allowed for increasing porosity and the formation of phosphate and carbonyl groups on the activated carbon surface. These surface modifications results in improved heavy metal removal in water.