Pioneering bio-derived greener and sustainable Cu/biochar nanoplates for expedient adsorption of DR 227 dye

Abstract

The present work reports a comparative study of fish scale biomass (FSBM), fish scale biochar (FSBC), acid treated fish scale biochar (ATFSBC), and a nano Cu-acid treated fish scale biochar composite (Cu/FS NCs), synthesized by using Punica granatum as a reducing and capping agent. All the experiments were performed in a batch process where the effect of pH (1.0–10.0), dose rate (0.05–0.1 g), dye initial concentration (10–150 ppm), and contact time (24 hours) were investigated for maximum adsorption of Direct Red (DR) 227 dye. Results showed that the Cu/FS NC adsorbent has the maximum degradation of DR-227 dye, i.e., 99.99% was found among all adsorbents. The highest value of q_e (mg g⁻¹) for Cu/FS NCs was obtained at optimum pH 2, dose rate 0.05 g, contact time 240 min, and concentration 120 ppm. The Freundlich model and the pseudo-second-order model match the dye adsorption process of DR-227. The reusability of Cu/FS NCs was maintained through cyclic testing, revealing negligible degradation in catalytic activity. Further identification of the material properties was achieved through SEM analysis, and it showed that the adsorbent was obtained in nanoplate form. Furthermore, FTIR spectra of the adsorbent were a clear indication of the formation of the material. So, the current study proposes that biomass-derived Cu nanoplates can be useful in targeting sustainability threats.