Bioleaching of heavy metals from spent batteries using Aspergillus nomius JAMK1

The present study focuses on recovery of heavy metals from e-waste fungus isolated from heavy metal rich industrial sewage soil. Molecular identification revealed the organism to be Aspergillus nomius and was designated as A. nomius JAMK1. The isolate was subjected for heavy metals uptake following two mechanisms: bioaccumulation and biosorption. Atomic absorption spectroscopy (AAS) was primarily used to analyse the heavy metal ions uptake and further confirmed by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDAX). Kinetics study was performed using pseudo-first-order, pseudo-second-order, Elovich, Weber and Morris and Boyd's kinetic model. Central composite design, a subunit of response surface methodology, was utilized to obtain design of experiments for the experimental values in bioaccumulation. Adsorption isotherm assessment, conducted for the biosorption activity of strain JAMK1, showed that the process followed Freundlich mode of isotherm. The adsorbed heavy metals were comprehensively desorbed from the metal-loaded sorbent using HCl and Ca(OH)(2). The activity of A. nomius JAMK1 in bioleaching of metals from spent batteries was studied and analysed using AAS, X-ray diffraction, SEM and EDAX. The investigation proved A. nomius JAMK1 to be a potential strain for heavy metals uptake from aqueous solution as well as electronic waste.