Adsorption of Heavy Metals Using Activated Carbon Synthesized from the Residues of Medicinal Herbs

In this study, we used activated carbon produced from the biomass recovered from the medicinal plant residue for the adsorption process. This study aimed to investigate its effectiveness to adsorb heavy metals at different activating methods and operating conditions. The carbonized residue was activated using both physical and chemical activations to produce activated carbon. The physical and chemical properties of the prepared activated carbon and iodine adsorption capacity were measured and the performance of the activated carbon as an adsorbent examined. Results showed that the physical activation exhibited optimum operating conditions at the carbonization temperature of 650 degrees C for 60 min and moisture content of 10%. Experimental results on adsorption with synthetic wastewater showed that the optimal operating conditions for the removal of Pb2+, Zn2+, and Cd2+ ions were at pH 5, temperature of 25 degrees C, adsorbent dosage of 5 g/L and contact time of 1.5 h. Adsorption index of the Freundlich adsorption isotherm was higher, and the 1/n values of Cd2+, Pb2+ and Zn2+ ions was 0.37, 0.35 and 0.22, respectively. Results showed that the activated carbon from the sample material exhibited a high regeneration capacity.