Multimetal bioremediation from aqueous solution using dead biomass of Mucor sp. NRCC6 derived from detergent...

Among ten metal-tolerant fungal isolates obtained from the microbiomes of detergent industry effluent, Mucor sp. NRCC6 showed the highest tolerance and an adaptive behavior toward the heavy metals Ni²⁺, Pb²⁺, Mn²⁺, and Zn²⁺. It gave the highest growth rates 0.790 ± 0.59, 0.832 ± 0.32, 0.774 ± 0.40, and 0.741 ± 1.06 mm/h along with the lowest growth inhibition 9.19, 4.37, 11.04, and 14.83% in the presence of Pb²⁺, Zn²⁺, Ni²⁺, and Mn²⁺, respectively, at a concentration of 5.0 g/L. Then, Mucor sp. NRCC6 was selected as a biotrap for the removal of these heavy metals. The optimized operating conditions were detected to be pH 6.0 for Pb²⁺, Zn²⁺, and Mn²⁺ and pH 5.5 for Ni²⁺ at 30 °C; agitation speed 150 rpm; contact time 30 min for Mn²⁺ and Ni²⁺, 30-60 min for Pb²⁺, and 90-180 min for Zn²⁺; NRCC6 biomass dosage 5.0 g/L for Ni²⁺ and Pb²⁺ and 10.0 g/L for Mn²⁺ and Zn²⁺; and initial concentration 12 mg/L of each ion in the multimetal aqueous solutions. Under these optimized conditions, the adsorption capacity for Pb²⁺, Ni²⁺, Mn²⁺, and Zn²⁺ reached 98.75, 59.25, 58.33, and 50.83%. The Langmuir isotherm was the best for describing the adsorption of Zn²⁺ (0.970) and Mn²⁺ (0.977). The Freundlich isotherm significantly giving a good fit to the adsorption of Pb²⁺ (0.998) while the adsorption of Ni²⁺ onto NRCC6 biomass can follow DKR (0.998). Furthermore, the current study revealed that Mucor sp. NRCC6 fungus is a new efficient and eco-friendly method that revealed a maximum removal of 100% for Pb²⁺ and Zn²⁺ as well as 97.39, 88.70, 78.95, 74.0, 70.22, 68.57, and 60.0% for Ni²⁺, Mn²⁺, Cd²⁺, Cu²⁺, Fe³⁺, As²⁺, and Cr⁶⁺ from the industrial wastewater, respectively.