Application of Box-Behnken Model to Study the Biosorption of Chromium Cr(VI) Ion by Aspergillus niger isolated from Polluted Site

The biosorption of Cr(VI) metal ion by fungal biomass isolated from polluted soil samples was optimized by using response surface methodology (RSM). The box-behnken design of RSM was used to optimize the parameters such as pH, temperature, initial metal ion concentration and contact time. The isolated strain was identified as Aspergillus niger. Total thirty experiments were used to evaluate the interactions between the selected independent variables. The results showed that the fungal biomass isolated from the polluted site impart an important environmental impact through biosorption of Cr(VI) metal ions from the metal solution. The maximum removal value of Cr(VI) obtained was 82.60 percent at pH 5.0 with 103.55 ppm initial metal ion concentration, 35°C temperature and contact time of 60 minutes.