Synthesis of ASB-CuO nanocomposite for efficient cyanide degradation from aqueous systems: Fundamentals and potential applications to tailings water from gold operations

Abstract

Synthesis of nanoparticles through physical and chemical processes for several applications is common, but it is often expensive and involves inorganic chemicals. For the first time, in this study, a simple and novel approach for producing a CuO-loaded Alocasia macrorrhizos stem biomass (ASB–CuO) nanocomposite that is effective in cyanide degradation has been presented. The CuO nanoparticles (CuO NPs) synthesis was revealed by UV spectroscopy at a wavelength of 247 nm. The CuO NPs on the dried ASB surface were well scattered and mostly spherical, as revealed by SEM/EDX analysis. The crystalline structure of ASB–CuO was established by XRD investigations. For the elimination of cyanide from aqueous systems, it was shown that the nanocomposite of ASB–CuO had a higher removal performance than the raw ASB. A catalytic test on the efficacy of ASB–CuO in removing cyanide (100 mg/L) from wastewater revealed a removal efficiency of 90% within 60 min. Different factors, such as contact time, dosage, initial concentration, and temperature were examined. The cyanide removal followed pseudo-second-order kinetics with the ASB–CuO having higher rate constant than the raw ASB. Furthermore, the produced nanocomposite was able to remove 90% of cyanide from real wastewater samples, as demonstrated by removal studies on the tailings water samples of a gold cyanidation operation.