本研究以稻殼灰分為主原料，利用離子交換法製備矽-鋁二元氧化物擔體鎳觸媒，並於一大氣壓、573K ~ 923K下進行二氧化碳甲烷化反應活性測試，結果顯示矽-鋁二元氧化物擔體鎳觸媒於高溫下的熱穩定性能使甲烷化反應有高甲烷選擇率。 於觸媒製備方面，實驗結果發現：金屬載量愈低，則金屬分散度愈高；而適當的鍛燒程序，能夠控制觸媒表面金屬晶粒的大小及分佈，使其有較佳的催化活性。因此，欲使矽-鋁二元氧化物擔體鎳觸媒發揮最佳的催化效率，4.44 wt%的金屬載量、773K下4小時的鍛燒，由室溫升溫至773K的還原程序及923K下的甲烷化反應，將是最佳的製備及操作條件。且經由TPR及TPD技術的分析證實，以稻殼灰分製備而成的矽-鋁二元氧化物擔體﹙RHA-Al2O3﹚，其特殊的擔體表面性質有利於鎳金屬分散，乃是一種兼具高促進效果及經濟效益的甲烷化觸媒擔體。 RHA-Al2O3 binary oxide supported nickel catalyst prepared by ion exchange was examined in methanation of CO2 at 573 ~ 923K and high selectivity for CH4 formation was found at high reaction temperature due to its thermal stability. During the investigations of preparation conditions, effects of nickel loading, calcination temperature, calcination time, reaction time and reaction temperature on catalytic behavior were presented and discussed. The results indicate that the metal dispersion increases with decreasing of nickel loading; the CH4 selectivity depends on calcination conditions; the activity of nickel catalyst achieves a maximum value with a nickel loading of 4.44 wt% , calcined at 773K for 4h and reduced at 773K in CO2 hydrogenation at 973K. Moreover, by using TPR and H2-TPD techniques, RHA-Al2O3 is good for the dispersion of nickel and is a preferable and economic support.
