SYNTHESIS, ACTIVITY AND THERMAL STABILITY OF GOLD NANOPARTICLE ON MODIFIED NH4-Y TYPE ZEOLITE FOR COOXIDATION

Gold nanoparticle is the active catalyst for co oxidation at low temperature. this feature of gold basecatalysts is suitable to overcome the problem of cold-start problem of automobile exhaust twcconverters. in this study gold nanoparticle were deposited on modified nh4-y type zeolite. the activity ofsynthesized catalyst was measured in a fixed-bed quartz-tubular reactor (7mm i.d.) under atmosphericpressure. in order to investigate the catalytic activities toward co oxidation reaction, 31ml/min of air and0.155ml/min of carbon monoxide were mixed and then passed through the reactor. it was found thatactivity of au/y catalyst was 100% at 20°c. the thermal stability of au/y catalyst was measured at400°c for 4h. the activity of the catalyst was decreased to 65% at 20°c after thermal stability test.results of energy dispersive analysis by x-rays before and after thermal stability have showed that aucontent of these samples were 3.89% and 1.76, respectively. it was found that the amount of au contentdecreased after thermal stability process. fourier transform infrared (ft-ir) spectra showed no changesin framework structure of zeolite during thermal stabilization process of the catalyst.