Primary Study On The Motocycle Exhaust Gases Catalyst

In present paper, the works of the preparation of supporters and catalysts to control exhaust emissions of motocycles have been done in detail. Based on the advanced oxygen storage materials (CZ-X) and durable materials (YSZ-Al2O3) with high surface area, which have been investigated carefully, the performance of the catalyst relation to the composition, preparation method, preparation condition and the feature of the substrates have been studied. The light-off performance, and conversion efficiencies in converting HC,CO and NOx at various GHSV and at various air/fuel ratio were studied and aging testing and resistant to thermal shock of the catalysts testing were conduct . TWC catalysts for motocycles with high performance have been prepared.The three-way catalytic performance of the catalysts of the different noble metal-loaded the different supporters has been investigated. The results shown that the activity of the Pt-Rh catalyst was higher than that of the only Pd catalyst for saturation hydrocarbons (C3H8) conversion. Light-off temperature of the fresh Pt-Rh catalysts for HC,CO and NOx were 239℃,211℃and 217℃ respectively,that of the aged catalyst was 275℃,243℃and 261℃ respectively. It suggested that the catalyst with better low-temperature activity and durability. The performance of the catalyst was tested added oxygen storage materials CeO2-ZrO2 and CZ-X respectively, the results shown that the catalyst with higher durability after novel composition CZ-X was added, as well as the wider air-fuel ratio window. The catalysts keep high activity at GHSV ranging from 3.0×104h-1～6.0×104h-1 , it was shown that the GHSV property of the catalyst was better.The works of the test the catalysts resistance to thermal shock have been carried out, the results shown that the catalyst with stronger adhesion after treatment the metallic substrates in air at 850℃ keep about 10 hour and the mass loss of the catalyst tested was only 3wt%, the coating amount of the catalysts control in about 20% by weight of the substrates was better, which ensure the activity of the catalysts and prolong service life of the catalysts. The activity could be improved by increasing cell density of the metallic substrates.