PHENOL removal in refinery wastewater using mixed oxides prepared by green synthesis

Abstract

Mixed solid oxides are known for their excellent catalytic property and applications in environmental remediation. This study presents a green-synthesis route for magnesium oxide–titanium oxide, a mixed oxide demonstrated to possess high performance of phenol removal from hydrocarbon refinery process wastewater. Mixed oxide (MgO-TiO2) was prepared by using the whole extract from leaves of Piliostigma Thonningii as a reducing agent. A structural attribute of the mixed oxide was investigated using X-ray Diffractometer, High Resolution Scanning Electronic Microscopy and Energy Dispersive X-ray. Petroleum refinery raw wastewater having a phenol concentration of 19.961 mg/L was treated using green-synthesized mixed oxide. Adsorptive phenols removal up to 99.5% was achieved with a dosage of 0.04 g/100 mL at a temperature of 35 °C, and a contact time of 1.167 h. By this, the treated water meets the standard acceptable phenol concentration (0.1 mg/L) in wastewater of hydrocarbon refinery. Keywords: Green synthesis; Magnesium oxide; Mixed oxide; Phenol; Process wastewater; Titanium oxide.