Removal of Copper from Industrial Effluents Using New Biosorbents: Thermodynamic, Kinetic and Isothermal Studies and Applications

Abstract

New effective biosorbents for the removal of Cu2+ ions from industrial wastewater were identified. Premna serratifolia plant stem powder (PSSP) and its active carbon (PSSAC) were strongly observed to adsorb Cu2+ ions in a wide pH range 6 to 9. Extraction conditions were optimized and sorption capacities are found to be 40.1 mg/g for PSSP and 45.6 mg/g for PSSAC. The extraction of Cu2+ from simulated solutions of concentration 25 mg/L were 85% with PSSP and 90% with PSSAC. Common co-ions were marginally interfered. The spent sorbents can be regenerated and reused. Thermodynamic studies revealed the spontaneity and favourability of the sorption process at high temperatures. Homogeneity of sorbents surfaces and monolayer formation of Cu2+ ion on the surfaces, were inferred from the analysis of adsorption isotherms. Pseudo-second order kinetics explain well the sorption. The developed adsorbents were also effectively applied to treat polluted industrial effluents for the removal of Cu2+ ions.