Article thumbnail

Kinetic and mechanism studies of the adsorption of lead onto waste cow bone powder (WCBP) surfaces

By J. Cha, M. Cui, M. Jang, S.H. Cho, D.H. Moon and J. Khim


This study examines the adsorption isotherms, kinetics and mechanisms of Pb2+ sorption onto waste cow bone powder (WCBP) surfaces. The concentrations of Pb2+ in the study range from 10 to 90 mg/L. Although the sorption data follow the Langmuir and Freundlich isotherm, a detailed examination reveals that surface sorption or complexation and co-precipitation are the most important mechanisms, along with possibly ion exchange and solid diffusion also contributing to the overall sorption process. The co-precipitation of Pb2+ with the calcium hydroxyapatite (Ca-HAP) is implied by significant changes in Ca2+ and PO4 3- concentrations during the metal sorption processes. The Pb2+ sorption onto the WCBP surface by metal complexation with surface functional groups such as ≡ POH. The major metal surface species are likely to be ≡ POPb+. The sorption isotherm results indicated that Pb2+ sorption onto the Langmuir and Freundlich constant qmax and KF is 9.52 and 8.18 mg g-1, respectively. Sorption kinetics results indicated that Pb2+ sorption onto WCBP was pseudo-second-order rate constants K2 was 1.12 g mg-1 h-1. The main mechanism is adsorption or surface complexation (≡POPb+: 61.6%), co-precipitation or ion exchange [Ca3.93 Pb1.07 (PO4)3 (OH): 21.4%] and other precipitation [Pb 50 mg L-1 and natural pH: 17%). Sorption isotherms showed that WCBP has a much higher Pb2+ removal rate in an aqueous solution; the greater capability of WCBP to remove aqueous Pb2+ indicates its potential as another promising way to remediate Pb2+-contaminated media. © 2010 Springer Science+Business Media B.V

Topics: TA Engineering (General). Civil engineering (General)
Publisher: 'Springer Science and Business Media LLC'
Year: 2011
DOI identifier: 10.1007/s10653-010-9357-z
OAI identifier:
Provided by: UM Digital Repository

Suggested articles

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.