An efficient, sustainable catalytic ozonation over Ag/ZrO2 and Ru/ZrO2 for degradation and mineralization of Trichlorophenol

Abstract

The enhanced industrialisation and urbanisation have made it difficult to maintain a decent water contaminants ratio which has led to the discovery of many water purification techniques. The most hazardous of all the pollutants are phenols which are considered ‘Persistent organic pollutants’ owing to its high stability and resistance to degradation. Advanced oxidative processes have been ascertained to help get rid of unwanted pollutants with resistance to classical water treatment techniques. In this work we have synthesised hybrid catalytic nano-composites by doping Ag2O and RuO2 to Zirconia. The prepared nanocomposites have been characterised using various analytical techniques such as PXRD (Powder X-Ray Diffraction), BET (Brunauer–Emmett–Teller), SEM (Scanning Electron Microscopy), EDX (Energy Dispersive X-ray spectrometry), and TEM (transmission electron microscopy). These catalysts were employed in combination with ozonation to study the degradation of trichlorophenols (TCPs) present in water. Later the external factors and internal factors that affect the degradation process were optimised. We were able to gather value added products such as 3,4,6-trihydroxycyclohexa-3,5-diene-1,2-dione (THCD), 3,5-dihydroxycyclohexa-3,5-diene-1,2-dione (DHCD), (E)-3-hydroxy-4,5-dioxohex-2-enedioic acid (HDHA), 2-oxomalonic acid (OMA) and oxalic acid (OA) and successfully achieved complete mineralisation of the target phenolic pollutants within two hours. The obtained value-added products were characterised and confirmed by significant spectroscopic techniques (GC-MS, FTIR, 1H NMR and 13C NMR). These catalysts showed high degradation capacity and reusability. The advantage of using this process is the eco-friendly or green nature of the reaction system.