Catalytic Combustion of Acrylonitrile over CuCeOx-HBETA Catalysts

Abstract

Purpose: Evaluate the acrylonitrile combustion using copper and cerium catalysts supported on BETA zeolite (CuCeOx-HBETA), aiming to reduce the emission of this pollutant in industrial exhaust gases.   Theoretical framework: Acrylonitrile (ACN) is one of the most used monomers in the chemical industry. However, it is a volatile organic compound (VOC) of high toxicity, being present in the exhaust gases of its own production process. In this context, selective catalytic combustion (SCC) stands as a highly promising technology for the removal of ACN in industrial gas effluents.   Method: CuCeOx-HBETA catalysts were prepared by wet impregnation. For characterize the catalysts, the techniques of X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and reduction with hydrogen at programmed temperature (TPR-H2) were used. Catalytic tests were carried out on ACN combustion by varying the reaction temperature.   Results and conclusion: The characterization results showed that copper and/or cerium oxides are present in the catalysts as nanoparticles. The addition of CeO2 improved the dispersion and facilitated the reducibility of CuO. The CuCeOx-HBETA catalysts achieved high ACN conversions at temperatures (300-350°C) much lower than traditional thermal combustion (T > 900°C). The greater activity of the catalysts can be attributed to the presence of highly dispersed CuO species and isolated Cu2+ ions. The 10Cu10Ce-HBETA catalyst, with a copper/cerium ratio equal to 1, was the most active due to the best synergy between copper and cerium species.   Research implications: The research indicates great potential for the use of CuCeOx-HBETA catalysts in the combustion of ACN.   Originality/value: This study brings new contributions to the research of catalysts to be applied in the catalytic combustion of nitrile compounds.