Catalytic activity of CuO n–La 2O 3/γ-Al 2O 3 for microwave assisted ClO 2 catalytic oxidation of phenol wastewater

Abstract

In order to develop a catalyst with high activity and stability for microwave assisted ClO 2 catalytic oxidation, we prepared CuO n –La 2O 3/γ-Al 2O 3 by impregnation–deposition method, and determined its properties using BET, XRF, XPS and chemical analysis techniques. The test results show that, better thermal ability of γ-Al 2O 3 and high loading of Cu in the catalyst can be achieved by adding La 2O 3. The microwave assisted ClO 2 catalytic oxidation process with CuO n –La 2O 3/γ-Al 2O 3 used as catalyst was also investigated, and the results show that the catalyst has an excellent catalytic activity in treating synthetic wastewater containing 100 mg/L phenol, and 91.66% of phenol and 50.35% of total organic carbon (TOC) can be removed under the optimum process conditions. Compared with no catalyst process, CuO n –La 2O 3/γ-Al 2O 3 can effectively degrade contaminants in short reaction time and with low oxidant dosage, extensive pH range. The comparison of phenol removal efficiency in the different process indicates that microwave irradiation and catalyst work together to oxidize phenol effectively. It can therefore be concluded from results and discussion that CuO n –La 2O 3/γ-Al 2O 3 is a suitable catalyst in microwave assisted ClO 2 catalytic oxidation process.