Summary: | 碩士 === 義守大學 === 生物技術與化學工程研究所碩士班 === 99 === Selective CO oxidation in rich hydrogen was studied over copper oxide supported on reverse micelles-synthesized ceria. Activity tests employing 1 or 2 % CO and O2 with hydrogen the balance were carried out over the catalysts of 5-20 wt% copper loading. It was found that the oxidation of CO was able to be initiated at low temperatures and 100% CO oxidation could be achieved at 100~120℃, yet retaining relatively high selectivity. The temperature for complete CO conversion was shifted to slightly higher value for catalysts of 10 and 20 wt% copper loadings. XRD and TEM characterizations verified it showing that copper particles would agglomerate and segregate on the surface of these catalysts, thereby resulting in poor dispersion of copper particles. BET tests revealed that catalyst surface area declined with the increase of copper loading, matched quite well with the aforementioned results. H2-TPR investigations pointed out that the reduction temperature of metal-support interfacial oxygen ions (α peak appearance) coincided well with that of complete CO oxidation. Experimental works at 130 ℃ studying competitive oxidation of CO and H2 at a temperature higher than that of hydrogen ‘light-off’ were carried out to provide evidence that CO has higher reactivity toward the interfacial oxygen ions, This study demonstrates the excellence of the microemulsion-synthesized catalysts in the selective CO oxidation.
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