Sorption Performance of Live and Heat-Inactivated Loofa-Immobilized Phanerochaete chrysosporium in Mercury Removal from Aqueous Solution

The sorption behavior of loofa-immobilized Phanerochaete chrysosporium mycelia in two forms, Live (L) and Heat-Inactivated (HIA), was studied for the removal of Hg2+ ions from aqueous solution. Using the Langmuir isotherm, the two key parameters for the sorption performance, qm and the coefficient b, were obtained; the qm values for Hg2+ ions were 72.46 mg/g and 92.59 mg/g and the b coefficients were 0.073 L/mg and 0.114 L/mg for the L and HIA biosorbents, respectively. Using the Freundlich isotherm, the values of kF were determined as 13.28 and 21.30, and the values of the coefficient n were 3.22 and 3.51 for the L and HIA biosorbents, respectively. Although the biosorption data were well fitted by both the Langmuir and Freundlich models, the Langmuir isotherm gave a better fit, with a higher correlation coefficient than the Freundlich model. Moreover, the essential characteristic of the Langmuir isotherm model, described as the separation factor, was indicative of the favorable adsorption of Hg2+ onto both of the test biosorbents (02ads were 1.16×10-3 g/mg·min and 1.08×10-3 g/mg·min for the L and HIA biosorbents, respectively. Regenerating the biosorbents was possible using hydrochloric acid to leach the sequestered mercury ions, providing an easy way to reduce the cost of the process. The prevailing criteria in the industrial selection and use of biosorbents were satisfactorily met by this system.