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Catalytic oxidation technology is a promising strategy to eliminate carbon monoxide (CO), volatile organic compounds (VOC) and other emissions from industrial boilers and to address ammonia (NH 3) escape. Herein, we demonstrate the potential of copper-cerium-zirconium mixed oxides or those supported on TiO 2 or ZSM-5 substrates for the simultaneous catalytic removal of CO, toluene and NH 3. Among them, CuCeZr/ZSM-5 exhibits the best co-processing ability for mixed gases. In situ infrared spectroscopy analyses suggest that there is a competitive adsorption among CO, toluene and NH 3 , and the inhibition is in descending order of toluene＞CO＞NH 3. Based on the physical-chemical characterizations, the Cu-Ce interfacial structure plays an important role in CO ignition at low temperatures. More importantly, the abundant acidic sites on the ZSM-5 support can improve the stability of adsorbed NH 3 at high temperatures, resulting in the best NH 3 catalytic oxidation performance of CuCeZr/ZSM-5 with no secondary pollutants of NO x. This study provides a strategy for the catalyst design to eliminate multiple pollutants targeting the properties of pollutants. [Display omitted] • Simultaneous removal of CO, toluene and NH 3 was achieved by CuCeZr based catalyst. • The best mixed gas treatment was observed for CuCeZr/ZSM-5 catalyst. • Cu-Ce interfacial structure allows preferential ignition of CO at low temperature. • The acidic sites on the ZSM-5 promoted the adsorption and oxidation of NH 3. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The catalytic self-sustained combustion of toluene was successfully developed. • CuCeZr/TiO 2 catalyst showed the excellent performance in self-sustained combustion. • TPO in N 2 atmosphere was used to investigate the role of lattice oxygen in toluene combustion. Abstract The catalytic self-sustained combustion of toluene over Cu x Mn 1-x Ce 0.75 Zr 0.25 /TiO 2 catalysts (x = 1, 0.5, 0) was studied in a microscale combustor. The catalytic activity is determined not only by the temperature with toluene conversion of 90% (T co), but also by the corresponding lean-combustion limits. It was found that the self-sustained combustion was achieved successfully over the catalysts, with the toluene concentrations of 0.35 con.%, 0.50 con.% and 1.00 con.%. According to T co, the activity decreased in the order of CuCe 0.75 Zr 0.25 /TiO 2 (234 °C)＞Cu 0.5 Mn 0.5 Ce 0.75 Zr 0.25 /TiO 2 (238 °C) ＞MnCe 0.75 Zr 0.25 /TiO 2 (284 °C). The excellent activity of CuCe 0.75 Zr 0.25 /TiO 2 catalyst could be ascribed to the high content of active lattice oxygen, good low-temperature reducibility and homogeneous dispersion, combined with the results of H 2 -TPR, O 2 -TPD and XPS. Furthermore, the results of in-situ DRIFT and temperature-programmed oxidation (TPO) of toluene in N 2 atmosphere suggested that toluene was adsorbed on the catalyst surface by removing α-H from methyl and combining with active oxygen specie to form benzyl group, which was finally oxidized into CO 2 and H 2 O with lattice oxygen. [ABSTRACT FROM AUTHOR]

Toluene was removed by dielectric barrier discharge coupling with Cu-Ce-Zr supported ZSM-5/TiO 2 /Al 2 O 3 catalysts. Copper, cerium, and zirconium species were highly dispersed on the support surface, and copper was mostly in Cu 2 + and Cu + state co-existed. The reaction process of toluene removal in the plasma-catalyst system was influenced by the support of the catalyst and it could be divided into three steps. Pure plasma and thermal catalytic chemistry triggered by background temperature played different roles in the different step. Large pore size, more oxygen vacancy and lattice oxygen in the CuCeZr/TiO 2 were responsible to the excellent toluene removal, CO 2 selectivity and energy yield. [ABSTRACT FROM AUTHOR]