Aspergillus tamarii mediated green synthesis of magnetic chitosan beads for sustainable remediation of wastewater contaminants.

The release of different hazardous substances into the water bodies during the industrial and textile processing stages is a serious problem in recent decades. This study focuses on the potentiality of FeO-NPs-based polymer in sustainable bioremediation of toxic substances from contaminated water. The biosynthesis of FeO-NPs by A. tamarii was performed for the first time. The effect of different independent variables on the FeO-NPs production were optimized using Plackett-Burman design and central composite design (CCD) of Response Surface Methodology. The optimum FeO-NPs production was determined using incubation period (24 h), temperature (30 °C), pH (12), stirring speed (100 rpm) and stirring time (1 h). The incorporation of FeO-NPs into chitosan beads was successfully performed using sol-gel method. The modified nanocomposite exhibited remarkable removal capability with improved stability and regeneration, compared to control beads. The optimal decolorization was 94.7% at 1.5 g/l after 90 min of treatment process. The reusability of biosorbent beads displayed 75.35% decolorization after the 7th cycle. The results showed a highly significant reduction of physico-chemical parameters (pH, TDS, TSS, COD, EC, and PO) of contaminated wastewater. The sorption trials marked FeO-NPs-based biopolymer as efficient and sustainable biosorbent for the elimination of hazardous toxic pollutants of wastewater in a high-speed rate.