Biosorption of mercury (II) from aqueous solution onto biomass of Aspergillus niger

Mercury (II) removal capacity in aqueous solution by Aspergillus niger biomass was analyzed by the atomic absorption spectrometry method. The fungus grew in 2000 ppm of the metal (20.3%). Biosorption was evaluated at different pH (3.5, 4.5, and 5.5) at different times. In addition, the effect of temperature in the range of 28°C to 45oC and removal at different initial concentrations of Hg (II) from 100 to 500 mg/L were also studied. The highest biosorption (83.2% with 100 mg/L of the metal, and 1 g of biomass) was 24 h at pH of 5.5 and 28oC. With regard to temperature, the highest removal was to 28oC, with an 83.2% removal at 24 h, and at higher biomass concentrations, the removal was most efficient (100% in 12 h with 5 g of biomass). Fungal biomass showed good removal capacity of the metal in situ, 69% removal in contaminated water, after 7 days of incubation and 5 g of biomass (100 mL water), so it can be used to remove industrial wastewater.