Removal of toluene from air streams by cobalt-copper bimetallic catalysts supported on sepiolite

Oxidative removal of toluene using copper and cobalt bimetallic catalysts with varying molar ratios supported on sepiolite was investigated. The catalysts prepared by a deposition precipitation method and were characterized using X-ray diffraction, nitrogen adsorption-desorption, field emission scanning electron microscopy, H-2-temperature-programmed reduction, transmission electron microscope, and inductive coupled plasma atomic emission spectroscopy. The species supported on sepiolite are Co3O4, CuO, and CuCo2O4. The activities of the tested catalysts increased in the order 0Co-4Cu/Sep <1Co-3Cu/Sep <4Co-0Cu/Sep <1Co-1Cu/Sep <3Co-1Cu/Sep. The latter exhibiting 90% toluene oxidative degradation at 288 degrees C within 15 h, having high selectivity towards CO2, and being stable at 300 degrees C up to 15 h. In conclusion, this study showed that sepiolite has excellent properties as a support.