Batch adsorption of Hg2+ and As3+ ions in Hospital wastewater using activated carbon from Balanites aegyptiaca and Detarium microcarpum

Abstract

Hospital waste water has a great potential to pollute the environment and severely affect public health. In order to remediate the toxic impact of arsenic (III) and mercury (II) ions, activated carbon were prepared from Detarium microcarpum and Balanites aegyptiaca fruit shells using 2M ortho phosphoric acid and 2M zinc chloride as activating agents. The adsorption of Hg2+ and As3+ were investigated by varying the dosage of the adsorbent, pH and period of contact using batch adsorption experiment. Concentrations of Hg2+ and As3+ were determined using ICP-AES. The results obtained indicated that all the adsorbent effectively removed As3+ and Hg2+ at varying experimental conditions. Optimum adsorption capacities were recorded at dosage values of 0.4 and 0.6 g for Hg2+ and As2+ respectively, pH of 6 and contact time between a0 and 15 minutes. Acitivated carbon synthesised from Detarium microcarpum using H3PO4 and ZnCl2 displayed better efficiencies than commercial activated carbon while others exhibited comparative adsorption efficiency. Therefore, the use of local materials can provide the needed technology that can help in the removal of hospital wastewater