Synthesis and characterization of some novel supported metal catalysts to control carbon monoxide emission from automobile vehicle exhaust

Abstract

Catalytic oxidation of carbon monoxide (CO) has been receiving attention due to higher amount of CO emission from automobile vehicle exhaust [Internal Combustion (IC) engine] which affects human health and environment to a great extent. The main focus of this piece of research is to synthesize a dedicated catalyst to control carbon monoxide emission selectively, in presence of carbon dioxide, hydrocarbons, and oxides of nitrogen and sulphur. A series of three catalysts is prepared. At first the supports were prepared. The CeO2-Al2O3 supported Cu catalyst is synthesized using conventional one step incipient wet impregnation method [named as Cu/CA]. Next, another CeO2-Al2O3 supported Cu catalyst is prepared using the same method where copper nitrate hydrate is used as a precursor for both support and the catalyst [named as Cu/CA-T]. A reference Cu/Al2O3 catalyst is also prepared. A detailed characterization study is undertaken to gain insight into the impact of the support morphology on the surface, structural and chemical properties. The catalysts are specifically characterized using a Scanning Electron Microscopy (SEM) for morphological details, X-ray Powder Diffraction (XRD) to identify the molecular structure, Fourier-Transform Infrared Spectroscopy (FTIR) based analysis to identify the functional groups, CHNS for elemental analysis, Thermo-Gravimetric Analysis (TGA) to establish the thermal stability and Brunauer–Emmett–Teller Analysis (BET) to find out the surface area to volume ratio and pore-size distribution. Finally, the synthesized catalysts are tested to determine their capability of removal of CO from automobile exhaust pipe. This study focus on the behaviour of catalysts at varying temperatures, gas compositions and flow rates, characteristic of automobile exhaust environments.