Rh-Mo-K/γ-Al_2O_3催化剂的TPR研究

用TPR对γ－Al2O3负载的Rh催化剂和Rh-Mo-K催化剂的还原性能进行了比较研究,发现Rh催化剂在氧化过程中形成两种Rh的氧化物；向Mo-K催化剂加入铑使得Mo易还原，且Rh的氧化物部分覆盖K-Mo物种，因而形成了含有Mo-O-Rh键的混合氧化物，该物种稳定，500℃时不能被H2还原,这些氧化物提高反应活性的机理可能是降低了CO化学吸咐，增大了表面H原子的浓度，从而有利于长碳链醇的合成.

A TPR study on Rh-Mo-K/γ-Al_2O_3 catalysts

A comparative study is made of the reduction behaviors between aluminiasupported Rh catalysts and Rh-Mo-K catalysts with different rhodium loading by means of TPR, Oxidation of the Rh catalysts results in two forms of Rh oxide different in reduction temperature, Addition of rhodium into Mo-K system makes molybdenum easier to be reduced, and Rhodium oxides partly cover the surface of Mo-K species, thereby forming mixed oxides containing Mo-O-Rh bonds, which are so stable that they cannot be reduced by treatment with hydrogen at 500℃, A possible mechanism of these mixed oxides in the alcohol synthesis reactions is that they reduce CO chemisorption, thereby to increase the surface concentration of hydrogen atoms, thus promoting a greater increase in the synthesis of long-chain alcohols,