CuO/zeolite catalyzed oxidation of gaseous toluene under microwave heating

Abstract

The development of a combined process of catalytic oxidation and microwave heating for treatment of toluene waste gas was described in this work. Toluene, a typical toxic volatile organic compound, was oxidized through a fixed bed reaction chamber containing zeolite-supported copper oxide (CuO/zeolite) catalyst mixed with silicon carbide (SiC), an excellent microwave-absorbing material. The target compound was efficiently degraded on the surface of the catalyst at high reaction temperature achieved by microwave-heated SiC. A set of experimental parameters, such as microwave power, air flow and the loading size of CuO etc., were investigated, respectively. The study demonstrated these parameters had critical impact on toluene degradation. Under optimal condition, 92% toluene was removed by this combined process, corresponding to an 80%–90% TOC removal rate. Furthermore, the catalyst was highly stable even after eight consecutive 6-h runs. At last, a hypothetical degradation pathway of toluene was proposed based on the experimental data obtained from gas chromatography-mass spectrum and Fourier transform infrared spectroscopy analyses.

Keywords

microwave / catalytic oxidation / CuO/zeolite catalyst / silicon carbide (SiC) / toluene

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Acknowledgements

This research was funded by the program for Changjiang Scholars and Innovative Research Team in University (PCSIRT) (No. IRT0853). The work was also supported by the Natural Science Basic Research Fund of Shaanxi Province (Project No. 2009JM7004) and the Key Science and Research Plan Project from Education Department of Shaanxi Province (Project No. 2010JS027).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg