利用完全液相法,以不同加料顺序制备了Cu—Zn—Al-Zr浆状催化剂.采用X射线粉末衍射、氮吸附、程序升温还原、X射线光电子能谱和氨程序升温脱附对其进行了表征,考察了Cu—Zn—Al-Zr浆状催化剂在合成气一步法合成二甲醚(DME)反应中的催化性能.结果表明,不同加料顺序对催化剂性能有显著的影响;Zr与Al同时加入时,催化剂的活性组分分散均匀,易于还原,表面结构稳定,拥有与CuZnAl催化剂相似的强弱酸中心;当Al/Zr=10/1时,催化剂的CO转化率和DME选择性与CuZnAl催化剂基本持平,但催化剂的流变性得到明显改善.
Cu-Zn-Al-Zr slurry catalysts were prepared by a complete liquid-phase technology, and characterized by means of X-ray diffraction, N2 adsorption, H2 temperature-programmed reduction, X-ray photoelectron spectroscopy and NH3 temperature-programmed desorption. The performance of the catalysts was evaluated in a slurry reactor for the synthesis of dimethyl ether (DME) from syngas. The results indicate that Zr-introducing manner influences significantly catalyst property. When Zr and A1 were added simultaneously, the active component of the catalyst was dispersed uniformly and reduced easily, meanwhile, the catalyst surface structure was stable and the sites of strong and weak acid coexisted. When the ratio of Al to Zr was 10 : 1, the CO conversion and DME selectivity of Cu-Zn-Al-Zr catalyst were comparative with those of CuZnAl catalyst, but its rheological property was obviously improved.