title: Batch studies of adsorption of copper and lead on activated carbon from Eucalyptus camaldulensis dehn. bark.
abstract: Powdered activated carbon (PAC) prepared from Eucalyptus camaldulensis Dehn. bark was tested for its adsorption capacity for Cu(II) and Pb(II). The experiment was conducted to investigate the effects of pH, contact time, initial metal concentration, and temperature. The best adsorption of both Cu(II) and Pb(II) occurred at pH 5, where the adsorption reached equilibrium within 45 min for the whole range of initial heavy metal concentrations (0.1-10 mmol/L). The adsorption kinetics was found to follow the pseudo-second order model where equilibrium adsorption capacities and adsorption rate constants increased with initial heavy metal concentrations. The adsorption isotherm followed Langmuir better than Freundlich models within the temperature range (25-60 degrees C). The maximum adsorption capacities (qm) occurred at 60 degrees C, where qm for Cu(II) and Pb(II) were 0.85 and 0.89 mmol/g, respectively. The enthalpies of Cu(II) and Pb(II) adsorption were 43.26 and 58.77 kJ/mol, respectively. The positive enthalpy of adsorption indicated an endothermic nature of the adsorption.
authors.affiliation: National Center of Excellence for Environmental and Hazardous Waste Management, Chulalongkorn University, Bangkok 10330, Thailand. phussadee@gmail.com
authors.forename: Phussadee
authors.initials: P
authors.lastname: Patnukao
authors.forename: Apipreeya
authors.initials: A
authors.lastname: Kongsuwan
authors.forename: Prasert
authors.initials: P
authors.lastname: Pavasant
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D003247:Conservation of Natural Resources; D003300:Copper / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry; D005052:Eucalyptus / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007854:Lead / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry*
chemical_list: D004785:Environmental Pollutants; D007854:Lead; D002244:Carbon; D003300:Copper