Biosorption of heavy metals from aqueous solution using modified activated carbon: comparison of linear and nonlinear methods

摘要

BACKGROUND: Biosorption of heavy metals from aqueous solution by modified activated carbon with Phanerochaete chrysosporium immobilised in Ca-alginate beads was investigated using a batch system and comparison of linear and nonlinear methods. RESULTS: The amount of Cu(II), Zn(II) and Pb(II) ion sorption by the beads was as follows: activated carbon with P. chrysosporium immobilised in Ca-alginate beads (ACFCA) (193.4, 181.8, 136.6 mg g(-1)) > activated carbon immobilised in Ca-alginate beads (ACCA) (1.74.8, 162.0, 130.7 mg g(-1)) > P. chrysosporium (F) (148.8, 125.6, 120.4 mg g(-1)) > activated carbon (AC) (138.8, 112.3, 109.3 mg g-1) > plain Ca-alginate beads (PCA) (125.4, 105.2, 98.2 mg g(-1)). The widely used Langmuir and Freundlich isotherm models were utilised to describe the biosorption equilibrium process. CONCLUSION: The results of this study suggest that the immobilisation of modified activated carbon with P. chrysosporium in Ca-alginate beads is suitable for a batch system. The isotherm parameters were estimated using linear and nonlinear regression analyses. The surface charge density of the biosorbents varied with the pH of the medium; the maximum biosorption of heavy metal ions on the biosorbents was obtained when the pH was between 5.6 and 7.4. (c) 2008 Society of Chemical Industry.