Isotherms and kinetic modelling of mycoremediation of hexavalent chromium contaminated wastewater

Abstract

Fungal biomass, Aspergillus terricola, was synthesized and employed for the biosorption of aqueous hexavalent chromium via batch technique. Insight into the nature of the surface chemistry and morphology of the fungal biomass was obtained via infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses, respectively. Also, the effect of selected process variables on the Aspergillus terricola biosorption capacity was elucidated. By employing isotherm and kinetic of varying parametric equations, the study investigated the effect of the number of parameters in a given model equation on their modelling performance. Marczewki-Jaroniec (4-parameter) and Fractal-like Pseudo-first order (3-parameter) model emerged as the best fit for isotherm and kinetics studies, respectively. The finding demonstrated the dependence of modelling accuracy on the inherent number of parameters of a given model. Meanwhile, the result of the mechanistic studies highlighted the superiority of the film diffusion mechanism during the hexavalent chromium biosorption, with a Langmuir maximum adsorption capacity (q max) of 87.3 mg. g-1. Notably, the biosorption efficacy of Aspergillus terricola biomass was succinctly demonstrated in the study.