Removal of Pb2+, Cd2+, Fe3+, and Sr2+ from Aqueous Solution by Selected Activated Carbons Derived from Date Pits

Abstract

Date pits (DP) are a huge solid waste in Egypt and are of little or no economic value and in fact present a disposal problem. The quantity of DP has been estimated at a million tons per year. DP have been used for the preparation of physically and chemically activated carbons. The raw materials were physically activated with steam or chemically by impregnation with 10% ferric chloride or calcium acetate. The present study deals with the factors affecting the uptake of (Pb2+, Cd2+, Fe3+, and Sr2+) as pollutants from aqueous solution using activated carbon developed from locally available material DP, by a one‐step steam pyrolysis in a batch mode. The effect of various factors—carbon type, carbon dosage, pH, initial concentration, and temperature on the adsorption capacity were quantitatively determined. The two equilibrium models, the Langmuir and Freundlich equations, were discussed. In this work, analyses and batch adsorption experiments have been carried out to characterize and understand the adsorption mechanism by modeling the adsorption kinetics. Concurrently removal of these cations from the aqueous medium were found to be affected by the presence of some anions, NO3 −, CO3 −2, SO4 −2 and masking agents, oxalic acid, and EDTA in solution.