Characterization of Se(IV) removal from aqueous solution by Aspergillus sp. J2

Experiments were conducted to study the removal of Se(IV) from aqueous solution using Aspergillus sp. J2. Batch Se(IV) removal experiments including biosorption kinetics, isotherms, effects of pH and competitive ions were investigated. Removal of Se(IV) was pH independent in the initial pH range from 4.0 to 10.7. The kinetics of Se(IV) sorption were better fit to both pseudo-second order and the pseudo-first order kinetic model. The Langmuir isotherm model gave a better fit to the experimental data than the Freundlich model. The presence of 0.2 mM competing anions, such as Cl−, NO3−, HCO3- and HPO42-, except SO42-, had no significant effect on the removal of Se(IV). The biosorption capacity increased from 4.14 to 5.67 mg/g as temperature increased from 18 to 38 °C, which indicated the endothermic nature of the Se(IV) removal by Aspergillus sp. J2. FTIR analysis indicated that the sulfur compound was involved in Se(IV) biosorption.

► Aspergillus   sp. J2 is used as an adsorbent for the biosorption of Se(IV).
► SO42- had significant effect on the biosorption of Se(IV).
► Removal of Se(IV) by Aspergillus sp. J2 was pH independent in the initial pH range 4.0–10.7.
► FTIR analysis suggested the role of sulfur compound in the Se(IV) biosorption process.