Catalytic Oxidation and Reduction of Gases

Much of the research on periodic operation of chemical reactors has concentrated on oxidation or reduction reactions. CO oxidation over noble metal catalysts such as Pt or Pt alloyed with other metals such as Rh, Pd and Zn has been the focus, although alumina supported oxides like NiO, K 2 O-V 2 O 5 and CuO were also investigated. Modulation in the presence of autonomous oscillations and over single crystal catalysts is discussed. Experiments on Pt as well as simulation suggest surface reconstruction on adsorption/desorption of CO along with the formation of oxygen reservoirs below the outermost layers of Pt atoms occurs in both forced and autonomous oscillation. Unexplained multiple resonance peaks in SO 2 oxidation over a vanadia catalyst are described. The chapter concludes with a section on reduction of nitrogen oxides.