La掺杂对CuO/CeO_(2)纳米棒催化剂的甲醇水蒸气重整制氢性能影响

Effect of Lanthanum Doping in CuO/CeO_(2) Nanorods on Catalytic Methanol Steam Reforming forHydrogen Production

为验证稀土元素掺杂对铜基催化剂在甲醇水蒸气重整反应中的性能影响,采用水热法和静电吸附法制备了1%CuO/CeO_(2)和1%CuO/Ce_(0.9)La_(0.1)O_(2)纳米棒催化剂。通过XRD、H_(2)-TPR、TEM等方法表征,证实了CuO与CeO_(2)之间的协同作用可以降低CuO的还原温度,掺杂的La元素可以均匀嵌入到CeO_(2)晶格中,降低了表相CuO的占比,从而减弱了CeO_(2)对CuO的还原温度降低程度。对其甲醇水蒸气重整反应的性能测试表明,在反应温度为400℃,两种催化剂的甲醇转化率均达到了100%,1%CuO/CeO_(2)的H_(2)产率更高,可达125.11mL·gcat^(-1)·min^(-1)。虽然La掺杂降低了大部分反应温度区间的甲醇转化率和氢气产率,但是在低温区间,1%CuO/CeO_(2)和1%CuO/Ce_(0.9)La_(0.1)O_(2)催化剂的甲醇转化率比较接近,后者的氢气产率明显高于前者,展示了La掺杂在低温区间的催化优势。

To verify the effect of rare earth element as an dopant on the performance of copper-based catalysts in methanol steam reforming,1%CuO/CeO_(2) and 1%CuO/Ce_(0.9)La_(0.1)O_(2) nanorod catalysts were prepared by hydrothermal method and elec⁃trostatic adsorption method.With assisted of XRD,H2-TPR,TEM and other characterizations,we confirmed that the syn⁃ergic effect between CuO and CeO_(2) can reduce the reduction temperature of CuO,and the La dopant can be uniformly em⁃bedded in the CeO_(2) lattice,thus reducing the proportion of surface CuO ratio and weakening the effect of CeO_(2) on reduction temperature of CuO.The performance tests of methanol steam reforming reaction showed that the methanol conversion of both catalysts reached 100%,and the H2 yield of 1%CuO/CeO_(2) was the better one of the two samples,reaching 125.11 mL·gcat^(-1)·min^(-1) at the reaction temperature of 400℃.Although doping La reduces methanol conversion and hydrogen yield in most reaction temperature ranges,the methanol conversions of 1%CuO/CeO_(2) and 1%CuO/Ce_(0.9)La_(0.1)O_(2) catalysts are close in the low temperature range,and the latter exhibited a significantly higher hydrogen yield than the former,demonstrating the catalytic advantage of doping La in the low temperature range.