Biosorption of Lead Using Immobilized Cells of Aspergillus niger

Fungal strain-Aspergillus niger was isolated from effluent of chemical and pharmaceutical industry using SDA agar. Pretreatment of live cells of Aspergillus niger was carried out. This dried biomass was immobilized in Ca-alginate beads. Ability of Pb biosorption with immobilized Aspergillus niger biomass was premeditated in the present study. Effect of Initial metal ion concentration, concentration of adsorbent and contact time doses on Lead (Pb) removal was determined. The concentration of lead in the filtrate was then analyzed by atomic absorption spectrophotometer. Suitable conditions for Aspergillus niger to take up Pb were shown to be at 50ppm lead as initial metal ion concentration using 2.4 grams of fungal beads as the adsorbent. The optimum contact time was found to be 150 minutes. Based on optimization results, biosorption and desorption processes were carried out. Biosorption experiment revealed that Aspergillus niger showed 74.61 per cent Pb removal. Desorption using EDTA retrieved 77.78 per cent Pb from the beads. Immobilized biomass offers many advantages including better reusability; high biomass loading and minimal clogging, increased substrate uptake and yield improvement, easier product recovery, thus reducing cost for equipment and energy demands.