Impact of silver-doped alumina nanocomposite on water decontamination by remodeling of biogenic waste.

Abstract

The main cause of various fatal diseases in humans and animals is environmental pollution. Ag-doped alumina nanocomposite was prepared using coffee husk extract with a large BET surface area of 126.58 m2g-1 and investigated for its antibacterial potential against both bacterial strains Escherichia coli and Salmonella typhimurium, and observed as an effective sorbent for removing the water pollution dye indigo carmine (IGC). The lowest concentration of the nanocomposite and the maximum contact time required to achieve complete inhibition of bacteria present in the contaminated water, as well as the capacity of sorption of IGC, were investigated. The results showed that the minimum inhibitory concentration of the Ag-doped alumina nanocomposite was 12µgmL-1 for both bacterial strains, with the highest inhibition occurring in E. coli. Moreover, the nanocomposite exhibited an experimental qt of 462.7mgg-1 from 160mg L-1 IGC solution at 50°C and followed the Langmuir model. The thermodynamic results showed that the process was endothermic, spontaneous, and physisorptive. The nanocomposite was used to fully treat water samples contaminated with 10mg L-1 concentrations of IGC. For six consecutive cycles, the reuse research showed an average efficiency of 95.72 ± 3.6%. Consequently, the synthesized Ag-doped alumina nanocomposite is suitable for treatments of contaminated water.