The Study Of Hydrogen Production By Biologic Glycerol Steam Reforming

The method of glycerol steam reforming to produce hydrogen was taken in a fixed bed in this paper. Different reforming conditions over different catalysts were studied for utilizing the byproduct of biological diesel and these explorations were also good for the industrial application of hydrogen generation from reforming.Firstly, the effects of reaction temperature, weight hourly space velocity (WHSV), water steam/carbon (S/C) on hydrogen production by glycerol steam reforming over char at atmospheric pressure had been studied. The results showed that the catalytic activity of char is better than char ash and silica sand. At the temperature of 800℃, WHSV of 1.5-1 and the S/C of 4, the hydrogen yield and the potential hydrogen yield reached 75.12% and 84.31%, respectively. The carbon conversion of gaseous phase was 89.09% under this condition.Secondly, the hydrogen production by glycerol steam reforming over Co-La-Ni/Al2O3 catalyst, which was made by impregnation method, was studied. The influences of reaction temperature, WHSV and S/C were investigated. The results showed that Co-La-Ni/Al2O3b catalyst has good catalysis to the hydrogen production by glycerol steam reforming. Hydrogen yield, potential hydrogen yield and carbon conversion were enhanced by increasing the reaction temperature and S/C. At the reaction temperature of 700℃, WHSV of 2.5 and the S/C of 3, the hydrogen yield, potential hydrogen yield and carbon conversion reached 75.12%, 84.31% and 89.08%, respectively. In addition, reforming effects and Co-La-Ni/Al2O3 catalyst’s stability were also enhanced by using two-stage fixed bed with char and Co-La-Ni/Al2O3 at the same time.Finally, the liquid products of glycerol steam reforming under the reaction condition (T=700℃, WHSV=1.5h-1,S/C=3) over char, Co-La-Ni/Al2O3 and in the two-stage fixed bed with char and Co-La-Ni/Al2O3 were analyzed by GC/MS, to deduce that the possible catalytic reaction paths. The results showed that the reaction paths and the selectivity of liquid products were changed over different catalysts.