Removal of lead from aqueous solutions by natural phosphate

The removal of lead ions from aqueous solution was studied in batch experiments using natural phosphate (NP). The effects of initial concentration of lead and initial pH of solution were investigated and the mechanism for removal of lead has been suggested. The data obtained from sorption isotherms at different temperatures conformed to the linear form of the Langmuir adsorption equation. The influence of NO3- and Cl- anions has been evaluated. The effect of varying levels of Cl- has significant influence on the sorption capacity of Pb2+, while NO3- did not. The abundance of natural phosphate, its low price and non-aggressive nature towards the environment are advantages for its utilization in point of view of wastewater and wastes clean up. (c) 2006 Elsevier B.V. All rights reserved.