Applicability of the Pinus bark (Pinus elliottii) for the adsorption of toxic heavy metals from aqueous solutions

Abstract

Current research evaluates the efficaciousness of pine (Pinus elliottii) bark as adsorbent of the toxic heavy metals cadmium (Cd), lead (Pb) and chromium (Cr) from aqueous solutions, at two pH conditions: 5.0 and 7.0. Approximately 500 mg of adsorbent material and 50 mL of solution contaminated by Cd, Pb and Cr at different concentrations prepared from standard solutions of each metal were added in 125 mL Erlenmeyer flasks. Flasks were stirred during 3h at 200 rpm at 25 o C. Further, 10 mL aliquots were then retrieved and concentration of metal Cd, Pb and Cr determined by AAS. Adsorption isotherms for each metal were consequently obtained and linearized according to Langmuir and Freundlich's mathematical models. Results show that the Pinus bark was efficacious in the removal of toxic heavy metals Cd, Pb and Cr from contaminated solutions and that the bark's adsorption capacity depended on pH solution.