Waste wood wool derived cellulose-based adsorbent for removal of heavy metal and bacterial contaminants: double-edged sword
摘要
The present study demonstrates the isolation of pure cellulose (CU) from Cedrus deodara (C. deodara) wood wool. Further, CU and modified mercaptobenzothiazole-functionalized CU (CU-MBT) were evaluated for adsorptive removal of Hg(II), Pb(II), Cd(II) ions and bacterial strains from water. Advanced characterizations through TGA, HR-TEM, FE-SEM, FTIR, XRD, EDX, BET and XPS were performed to analyze the adsorbents. The optimal pH for Pb(II) adsorption observed was 6, and for Cd(II) and Hg(II) was 7 with adsorption capacities 89.22, 103.09, 80.64 mg/g for Pb(II), Cd(II), and Hg(II) with CU, while CU-MBT exhibited 185.18, 178.57, and 140.84 mg/g for Pb(II), Cd(II), and Hg(II) respectively. CU and CU-MBT followed pseudo-second-order kinetics (R2 = 0.99) with equilibrium achieved in 90 min, showing high regeneration efficiency (9898.71%, 98.8% and 96.21%) and minimal loss over five cycles. Thermodynamic studies confirmed favourable adsorption (ΔG° values of -2.364, -2.338 and -12.781 kJ/mol), while DFT analysis revealed CU-MBT’s superior stability, lower energy gap (5.09 eV), and enhanced reactivity. Later, in the antibacterial analysis, the developed adsorbents revealed good antibacterial properties. In conclusion, CU-MBT has considerable calibre to adsorb Pb(II), Cd(II), and Hg(II) as well as bacterial species from water, demonstrating its potential in water treatment.