Hydrogenolysis of Glycerol to Monoalcohols over Supported Mo and W Catalysts
Hydrogenolysis of Glycerol to Monoalcohols over Supported Mo and W Catalysts
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DOI：
10.1021/acssuschemeng.6b01675
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发表时间：
2016-10-01
影响因子：
8.4
通讯作者：
Friedrich, Holger B.
中科院分区：
文献类型：
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作者：
Shozi, Mzamo L.;Dasireddy, Venkata D. B. C.;Friedrich, Holger B.
通过湿浸渍将MoO 3和WO 3负载在γ-Al 2 O3和SiO2上，标称负载量为10wt%。采用XRD、TPR、Pulse TPD、拉曼、TEM和BET比表面积等手段对催化剂进行了表征。氧化铝负载的催化剂被发现含有更高的布朗斯台德酸性相比，那些负载在二氧化硅上。在连续流动固定床反应器中，在250-325 ℃的温度范围和60巴的H-2压力下，在甘油的氢解中评价这些催化剂。所有催化剂都是活性的，活性随温度和布朗斯台德酸性的增加而增加。乙二醇和1，2-丙二醇的选择性随温度的升高而降低。平行地，对低级醇如甲醇、乙醇、2-丙醇和1-丙醇的选择性随着温度增加，因为乙二醇和1，2-丙二醇由于C-C键断裂而进一步反应成这些产物。在Mo/Al_2O_3、Mo/SiO_2、W/Al_2O_3和W/SiO_2上，低碳醇的总选择性分别为34.6%、64.8%、70.6%和54.6%。当H2：丙三醇比增加一倍时，Mo/Al 2 O3、Mo/SiO2、W/Al 2 O3和W/SiO2催化剂对低碳醇的总选择性分别提高到73.6%、72.8%、85.3%和66.1%。
MoO3 and WO3 were supported on gamma-Al2O3 and SiO2 with nominal loadings of 10 wt % via wet impregnation. The catalysts were characterized using XRD, TPR, Pulse TPD, Raman, TEM, and BET surface area. The alumina supported catalysts were found to contain higher Bronsted acidity compared to those supported on silica. These catalysts were evaluated in the hydrogenolysis of glycerol in a continuous flow fixed bed reactor in a temperature range of 250-325 degrees C and a H-2 pressure of 60 bar. All catalysts were active, with activity increasing with temperature as well as Bronsted acidity. The selectivity to ethylene glycol and 1,2-propanediol decreased with increase in temperature. In parallel, the selectivity to lower alcohols such as methanol, ethanol, 2-propanol, and 1-propanol increased with temperature as the ethylene glycol and 1,2-propanediol reacted further to these products due to C-C bond cleavage. The total selectivity to lower alcohols was 34.6, 64.8, 70.6, and 54.6% over Mo/Al2O3, Mo/SiO2, W/Al2O3, and W/SiO2 respectively. The total selectivity to lower alcohols increased to 73.6, 72.8, 85.3, and 66.1% over Mo/Al2O3, Mo/SiO2, W/Al2O3, and W/SiO2 respectively when the H2:glycerol ratio was doubled.