利用完全液相法制备了CuO/ZrO2浆状催化剂,通过X射线衍射、氮气吸附和程序升温还原等方法对催化剂的结构和织构性质进行了研究,并考察了CuO/ZrO2催化剂上CO加氢反应的性能.结果表明,本方法制备的CuO/ZrO2浆状催化剂具有与传统方法制备的固体催化剂相似的相结构;利用共沸蒸馏法进行表面处理后,CuO/ZrO2催化剂分散均匀且易于还原;CuO/ZrO2浆状催化剂用于CO加氢反应时,不需另外添加甲醇脱水剂就可以直接合成二甲醚,在473K时CuO/ZrO2对二甲醚的选择性达到92.1%,并且在15d的反应中催化剂呈现出良好的稳定性.
Slurry reactors have recently received more attention because of their advantages in caloric transfer. At present, the synthesis of dimethyl ether (DME) and methanol in slurry reactors is considered to be promising. The catalysts currently used in slurry reactors are all prepared by dispersing the traditional solid catalysts into an organic medium, which easily leads to the medium viscosity increase, defluidization decrease, and activity drop. This work suggests a novel method of preparing slurry catalysts for slurry reactors. Its main innovative thought lies in the direct preparation of catalysts from a solution to the slurry. Firstly, a catalyst precursor with a threedimensional net structure is prepared. Then the precursor is modified by solvent substitution or heterogeneous azeotropic distillation and treated by N2. After the treatment, a slurry catalyst is obtained. In this paper, two CuO/ZrO2 slurry catalysts were prepared by this new method and characterized by X-ray diffraction, N2 adsorption, and temperature-programmed reduction. The catalysts were evaluated in CO hydrogenation in a slurry reactor. The results show that the slurry catalysts have a phase structure similar to that of the catalyst prepared by the traditional method. The CuO/ZrO2 slurry catalyst modified by heterogeneous azeotropic distillation is highly dispersed. Using this CuO/ZrO2 slurry catalyst can directly synthesize DME from CO hydrogenation without adding any methanol dehydration component, and the highest DME selectivity reaches 92.10%. The slurry catalvst is stable during the reaction for fifteen davs. and no sianificant deactivation occurs.