Zahra Gholami
Tsinghua University, China
Title: Selective catalytic reduction of NOx by CO under oxygen condition over Cu:Ce catalysts supported by carbon nanotubes
Biography
Biography: Zahra Gholami
Abstract
Flue gas DeNOx process with no ammonia under oxygen condition and moderate temperatures is an ideal process with low cost, but is very challenging. In this work, catalytic activity of a series of carbon nanotubes (CNT) supported catalysts with different molar ratios of Cu:Ce prepared by co-impregnation method were studied for NO reduction by CO. Physicochemical properties of the catalysts were studied by means of SEM, TEM, XRD and XPS. The catalytic performances of these catalysts were evaluated through reduction of NO by CO. The 20wt.% Cu1:Ce3/CNT catalyst shows the highest NOx conversion of 96% at 220°C. Compared to some literatures results, the catalytic activity of the CNT-supported catalysts was significantly enhanced due to the synergistic interactions between Cu:Ce and good properties of CNTs such as high mechanical strength and electrical and thermal conductivity, adsorption and unique nanostructure. The redox equilibrium (Cu2++Ce3+↔Cu++Ce4+) was proposed here and the interaction between copper and cerium resulted in the formation of Cu+ species on the surface of the CNTs. The synergistic effect between surface oxygen vacancies and Cu+ species over the CNT supported catalysts plays an important role in the reduction of NO by CO under oxygen condition and the activity is mainly related to the electronegativity of elements, the reduction and adsorption behaviors of these catalysts. This work can provide some insights into the catalytic reactions among NO and CO under oxygen condition.