Integrated thermo-chemical embedment of waste fish-scale onto polyaniline matrix to destroy bacteria with simultaneous wastewater abatement.

Huge fish scale waste accumulation in the marketplace and the fishing industry is awkwardly challenging due to the pungent odor arising from trimethylamine N-oxide. Moreover, continuous release of toxic dyes from industries as effluents seriously endangers human health and aquatic ecosystems. In line with the waste-to-best protocol, an advanced material, namely polyaniline decorated fish scale biochar (PANI@FSB) composite, was prepared and employed for dual purposes. PANI@FSB was confirmed through Brunauer-Emmett-Teller (BET) surface area, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray (SEM-EDX), pHzpc, and powder X-ray diffraction (PXRD). As a bactericide, it acts upon Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with 76.7% and 94.4% destruction efficiencies, as confirmed by the colony counting method. Targeted membrane breakdown augments cell lysis, resulting in destruction. Besides, reactive oxygen species (ROS) generated from PANI@FSB may potentially oxidize the deoxynucleotide pool. Moreover, PANI@FSB rapidly scavenges Eriochrome black T (EBT) dye from wastewater. PANI@FSB could scavenge 94.573 mg/g of EBT dye at 500 mg/L concentration following the Freundlich isotherm model (R2 = 0.998) and pseudo-second-order (R2 = 0.999) model. 77.26% regeneration was obtained in methanol to re-establish the composite for 5 cycles. Favorably, the PANI@FSB displayed well in real wastewater over previously demonstrated materials. The long-hankered disposal issue was resolved with a second-generation adsorbent whose efficacy has been mapped with 73% dye removal efficiency.