TY - JOUR
T1 - Characterization of aqueous Pb(II) and Cd(II) biosorption on native and chemically modified Alstonia macrophylla saw dust
AU - Sewwandi, B. G.N.
AU - Vithanage, Meththika
AU - Wijesekara, S. S.R.M.D.H.R.
AU - Rajapaksha, Anushka Upamali
AU - Jayarathna, D. G.L.M.
AU - Mowjood, M. I.M.
PY - 2012
Y1 - 2012
N2 - This study was conducted in order to understand the mechanism of Cd and Pb adsorption in aqueous solutions by raw and modified saw dust (SD) of Alstonia macrophylla. The biosorbent was characterized by Boehm titration, specific surface area, scanning electron microscopy (SEM), X-ray energy dispersion (EDAX), and Fourier transform infrared (FTIR) analyses. SD was treated using organic acids and bases. Batch studies were conducted for raw and modified SD to determine the effect of initial concentration, pH, ionic strength, and contact time on metal adsorption. The specific surface area and total basic and acidic groups of SD were 77 m 2/g and 1521 and 2312 μmol/g, respectively. The adsorption of both metals onto SD was pH dependent. No ionic strength dependency was observed in adsorption of Cd and Pb at pH >6, indicating inner sphere surface complexation. Monolayer adsorption is dominant in both metal sorptions by SD. Furthermore, there is no competition between metals on adsorption and raw SD was found to be suitable for removal of Cd and Pb as compared to organic acid- or base-treated SD. Maximum adsorption capacity of SD for Cd and Pb were 30.6 and 204.2 mg/g, respectively. Results indicate that the A. macrophylla SD can be considered as a potential material for metal ion removal from wastewater.
AB - This study was conducted in order to understand the mechanism of Cd and Pb adsorption in aqueous solutions by raw and modified saw dust (SD) of Alstonia macrophylla. The biosorbent was characterized by Boehm titration, specific surface area, scanning electron microscopy (SEM), X-ray energy dispersion (EDAX), and Fourier transform infrared (FTIR) analyses. SD was treated using organic acids and bases. Batch studies were conducted for raw and modified SD to determine the effect of initial concentration, pH, ionic strength, and contact time on metal adsorption. The specific surface area and total basic and acidic groups of SD were 77 m 2/g and 1521 and 2312 μmol/g, respectively. The adsorption of both metals onto SD was pH dependent. No ionic strength dependency was observed in adsorption of Cd and Pb at pH >6, indicating inner sphere surface complexation. Monolayer adsorption is dominant in both metal sorptions by SD. Furthermore, there is no competition between metals on adsorption and raw SD was found to be suitable for removal of Cd and Pb as compared to organic acid- or base-treated SD. Maximum adsorption capacity of SD for Cd and Pb were 30.6 and 204.2 mg/g, respectively. Results indicate that the A. macrophylla SD can be considered as a potential material for metal ion removal from wastewater.
KW - Biosorption
KW - Isotherms
KW - Kinetics
KW - Surface modification
UR - http://www.scopus.com/inward/record.url?scp=84862860700&partnerID=8YFLogxK
U2 - 10.1080/10889868.2012.665963
DO - 10.1080/10889868.2012.665963
M3 - Article
AN - SCOPUS:84862860700
SN - 1088-9868
VL - 16
SP - 113
EP - 124
JO - Bioremediation Journal
JF - Bioremediation Journal
IS - 2
ER -