Evaluation of Aspergillus tamarii NRC 3 biomass as a biosorbent for removal and recovery of heavy metals from contaminated aqueous solutions

Abstract

Abstract Background Biomass produced as a byproduct from the β-mannanase production process by Aspergillus tamarii NRC 3was evaluated as a biosorbent for the removal and recovery of some heavy metal ions. Results Under optimal conditions, the isolated strain recorded the highest β-mannanase activity (31.88 Uml−1). Thus, the biomass produced from mannanase production process as a byproduct was evaluated as a biosorbent for the removal and recovery of some heavy metal ions from aqueous solutions and an industrial wastewater. The fungal biomass was found to be efficient for the removal of Cu+2 and some heavy metal ions. The biosorption process of copper(II) by Aspergillus tamarii NRC 3 biomass was affected by changing of time, temperature, pH, metal ions concentration, the presence of some heavy metals, and biomass concentration. The rate of Cu+2 uptake from Cu+2solution proceeded rapidly, and it appeared to be virtually complete during the initial 5 min (92%); the maximum uptake of Cu+2 appeared at 30 °C, pH 5, and biomass concentration 5 g w/w. On the other hand, the fungal biomass was to remove considerable proportion of Pb2+, Co+2, Ni2+, Fe+3, and Cr3+ in addition to Cu2+. The uptake of Cu+2 by pretreated biomass was studied. Recovery of the sorbed metal ions by desorbing agents and the potential reuse of the regenerated biomass in metal ions uptake (reloading) were evaluated. Conclusions Aspergillus tamarii NRC 3 biomass seems to be quite feasible in the removal of heavy metal ions especially Cu+2 from aqueous solutions.

Keywords

• Aspergillus tamarii NRC 3
• Heavy metal ions
• Sorption
• Desorption
• Reloading