Abstract：
Cu-Zn-Al and Cu-Zn-Al-no hydrotalcite precursors, which were respectively aged and un-aged during the preparation process, were prepared by coprecipitation. After the hydrotalcite precursors were calcined and reduced, Cu-based catalysts were obtained. The effect of ageing on the structure and performance of the catalysts for the hydrogenolysis of glycerol was studied by means of H2-TPR, XRD, H2-TPD, NH3-TPD and CO2-TPD and activity test. Also, the effect of the reaction conditions on the performance of Cu-Zn-Al catalyst was investigated. After calcination at 450 ℃, the hydrotalcite-like precursors were transformed to the mixed oxides without hydrotalcitelike structure, in which Cu species dispersed well. Cu-Zn-Al-no and Cu-Zn-Al had similar reducibility. After reduction at 270 ℃, the mixed oxides were converted to Cu-based catalysts. Compared with the Cu-Zn-Al-no, Cu-Zn-Al had larger active surface, more acid sites and less basic sites. Thus, in the hydrogenolysis of glycerol, the Cu-Zn-Al catalyst showed better activity, selectivity and stability than the Cu-Zn-Al-no catalyst. Under the condition of 220 ℃, 3.0 MPa H2 pressure, H2/glycerol molar ratio of 18.9, space velocity of 1.89 h-1 and 60%(mass fraction) glycerol aqueous solution, the Cu-Zn-Al catalyst gave glycerol conversion of 100% and 1,2-propanediol selectivity of 96%.
LI Li, YANG Juan, YU Lei, CHEN Ji-Xiang.Performance of Cu-Zn-Al Catalyst for Hydrogenolysis of Glycerol to 1,2-Propanediol[J]. Chemcial Industry and Engineering, 2013,30(4): 16-22
2013, Vol. 30 
