CuZnAl催化剂甲醇水蒸气重整制氢催化性能研究

采用共沉淀法制备一系列CuZn和CuZnAl催化剂，考察了催化剂对甲醇水蒸气重整制氢反应的催化性能，并采用BET，XRD，H2-TPR等对催化剂进行表征，以探讨Al和Cu/Zn比对催化剂活性的影响。在合适的Cu/Zn比时，引入Al能提高催化剂的比表面积和活性组分的分散度，以及稳定表面活性物种。对比试验结果表明：在所考察的CuZnAl催化剂中，Cu50Zn40Al10催化剂对甲醇水蒸气重整反应的催化活性最高，在温度250 ℃、压力1 MPa、 n（H2O）/n（CH3OH） = 1.5、体积空速为0.56 h-1的条件下，甲醇转化率达到100%，氢气产率达到 97.7%；经过200 h连续实验，Cu50Zn40Al10催化剂上甲醇蒸汽重整反应的转化率稳定在97%左右，其稳定性明显优越于Cu50Zn40催化剂。

HYDROGEN PRODUCTION FROM METHANOL STEAM REFORMING OVER CuZnAl CATALYSTS

A series of CuZn and CuZnAl catalysts were prepared by co-precipitation method. The catalytic performance of these catalysts for methanol steam reforming was investigated. The catalysts were characterized by BET, XRD, H2-TPR and N2O chemisorptions to explore the effect of the introduction of Al into CuZn catalyst. The results show that with the moderate ratio of Cu/Zn, the addition of Al can enlarge the specific surface area of CuZn catalyst and promote the dispersion and stability of Cu species on the catalyst surface and that the Cu50Zn40Al10 catalyst exhibits the highest catalytic activity for methanol steam reforming in the tested CuZnAl catalysts. The methanol conversion reaches 100% and the hydrogen yield is up to 97.7% under the reaction conditions: T=250 oC and P=1.0 MPa, H2O/CH3OH=1.5 molar ratio, VHSV=0.56 h-1. The Cu50Zn40Al10 catalyst has the excellent catalytic stability for methanol steam reforming during 200 h on stream and the methanol conversion has been kept at around 97%, much better than that of Cu50Zn40.