Use of Nano-Porous Calcium Silicate for Heavy Metal Removal from Aqueous Solutions

Abstract

Water is indispensable for our life and fresh water resources are becoming rich by heavy metals particularly by industrial wastes. Heavy metals are very harmful to the living organisms and accumulated in the food chain. Removal of heavy metals are therefore very important for protection of ecological systems. In this study, nano-porous calcium silicate produced from Rice Hull Ash in the laboratory, was used for the adsorption of copper, lead and zinc ions from an aqueous solution. The three elements – copper, lead and zinc – were adsorbed on the calcium silicate surface in ratios of 90-96 % in the first 15 minutes. Before and after the adsorption experiments, FTIR analyses of calcium silicate samples were done to investigate the adsorption type which can be chemical or physical.

Keywords

• Nano-porous,calcium silicate,heavy metal,adsorption,FTIR spectra

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