Development of alumina-supported platinum catalyst for carbonmonoxide and hydrocarbon oxidation

Abstract

The objective of this study is to enhance the performance of platinum supported on gamma-alumina catalysts for CO and propane abatement by replacing calcination step with catalyst pretreatment in exhaust gas technique. The experiments were carried out in a quartz tube reactor with inside diameter of 0.6 cm in the temperature range of 150-700 ℃. The feed gas composition comprised 0.05 vol.%NO, 0.3 vol.%CO, 0.215 vol.% propane and 0.5-5 vol.% oxygen at gas hourly space velocity of 15,000 h-1. It was found that the temperatures for the 50% conversion (light-off temperature) of CO and propane were reduced by 15% and 20%, respectively. The suitable condition for the pretreatment of catalyst prepared from platinum tetrammine dichloride [Pt(NH3)4Cl2] precursor was the condition under rich condition (S=0.8) in the temperature range of 300-600 ℃. It was also found that the platinum supported on alumina and washcoat monolithic catalyst reached the maximum NO conversion of 80% at 500-700 ℃. When the pretreated catalyst was adopted, the light-off temperature for 50% NO conversion was reduced by 15%.