| Summary: | 碩士 === 國立中央大學 === 化學工程與材料工程研究所 === 90 ===
In our study ,the catalysts of CuB/SiO2 and Me-CuB/SiO2(Me: Cr, Th, W) were prepared by a reductive-impregnation method. Using butyradehyde liquid hydrogenation reaction searched suitable preparation conditions . Then, we probed to the catalysis property in selectivity hydrogenation of furfural, crotonaldehyde and citral ,and compared with CuB, Cu/SiO2 and Copper chromite.
The suitable preparation conditions were base on the conversions, using copper nitrate precursor salt impregnated into SiO2 and furthermore passing through 100℃drying and 140℃calcination, the feeding rate of NaBH4 solusion about 6 ml/min and the copper salt/ NaBH4ratio of 1/3 was the optimal choices for preparing CuB/SiO2 and Me-CuB/SiO2 catalysts.
In catalyst characterization, these borons of CuB/SiO2 catalyst were containing more than non-surport catalyst. CuB could loaded averagely above SiO2 ,and then didn’t block pore of surport. Diference from other amorphous Me-B catalysts, CuB/SiO2 is crystal. Passing through surporting, CuB could promote its stability of heat ,and doppimgTh and Cr could furthermore upgrate its dispersion and stability.
In activity measurement, 10% loading had best activity in liquid hydrogenation and was better than CuB, Cu/SiO2, by dopping Cr, its activity could to compare favorably with copper chromite. In furfural hydrogenation reaction, major product was reduced the carbonyl bond to produce furfuryl alcohol and no residue was found. In crotonaldehyde hydrogenation reaction, the major product in 3 h was reduced conjugated C=C bond to produce butyraldehyde, with reaction time increasing, butyradehyde could proceed to butanol. In citral hydrogenation reaction, owing to steric hiderence effect, the major product was reduced the carbonyl bond to produce Nerol and Geraniol, and others were citronellal, with reaction time increasing, citronellal could proceed to citronellol.
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