Preparation of Active Catalysts by Mechanical Alloying

利用振动磨研究了机械力化学对催化反应的影响。试验反应为（1）环己烯脱氢和（2）费托合成。（1）在氦气气氛下，采用振动球磨法对镍粉进行机械活化。机械力化学活化的镍粉在室温下也能催化环己烯脱氢。镍、铁混合催化剂具有较高的催化活性。结果表明，铁粉对镍的球磨过程有促进作用。（2）使用铁粉和镍粉作为催化剂。当反应气体混合物（氢气和一氧化碳）与预活化粉末在120 ℃下加热3小时时，观察到催化反应并形成少量甲烷。当在120 ℃下在反应气体下进行研磨时，产物即甲烷的量增加。虽然铁的催化活性比镍低，但在球磨条件下与铁进行催化反应可生成乙烷和丙烷。可以得出结论，即使在120 ℃下，通过机械化学活化也可以进行费托合成。

Mechanochemical effects on catalytic reactions were carried out using vibromill. The test reactions were(1)dehydrogenation of cyclohexene and(2)Fischer-Tropsch synthesis.(1)Nickel powder was mechanically activated by vibromilling under helium atmosphere. Catalytic dehydrogenation of cyclohexene occurred by the mechanochemically activated nickel powder even at room temperature. High catalytic activity was observed with mixed catalyst of nickel and iron. It was found that milling process of nickel was accelerated by iron powder.(2)Iron and nickel powders were used as a catalyst. When reactant gas mixture(hydrogen and carbon monoxide)was heated with preactivated powders at 120 C for 3 hr, catalytic reaction was observed and a small amount of methane was formed. When milling was carried out under the reactant gas at 120 C, the amount of product, that is, methane increased. Although iron has a lower catalytic activity than nickel, ethane and propane were produced by catalytic reaction with iron under milling conditions. It can be concluded that Fischer-Tropsch synthesis can be performed even at 120 C by mechanochemical activation.