Document Type
Article
Publication Date
1-1-2011
Abstract
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.
Keywords
Adsorption isotherm, Kinetics, Lead, Mechanism, Waste cow bone powder, apatite, calcium, phosphate, adsorption, complexation, diffusion, ion exchange, precipitation (chemistry), reaction kinetics, solid waste, animal, article, bone, cattle, chemistry, ecosystem restoration, methodology, pollutant, surface property, Animals, Apatites, Bone and Bones, Environmental Pollutants Environmental Remediation, Phosphates, Surface Properties
Divisions
fac_eng
Publication Title
Environmental Geochemistry and Health
Volume
33
Issue
SUPPL.
Additional Information
Cha, Jihoon Cui, Mingcan Jang, Min Cho, Sang-Hyun Moon, Deok Hyun Khim, Jeehyeong eng Research Support, Non-U.S. Gov't Netherlands 2010/11/04 06:00 Environ Geochem Health. 2011 Jan;33 Suppl 1:81-9. doi: 10.1007/s10653-010-9357-z. Epub 2010 Nov 3.