丙烷在负载型催化剂上脱氢反应的研究——Ⅷ.丙烷在负载型金属催化剂上临氢脱氢

INVESTIGATION ON DEHYDROGENATION OF PROPANE OVER SUPPORTEDBI-COMPO.NENT CATALYSTS Ⅷ. DEHYDROGENATION OF PROPANE ON SUPPORTED MATAL CATALYSTS

通过对丙烷在负载型金属催化剂上临氢脱氢反应性能的考察,发现除负载型Pt、Pd等具有脱氢活性外;负载型Cu也同样具有脱氢活性,并且随Cu载量增加而升高。对催化剂稳定性研究结果表明,载体与金属组分间相互作用是不容忽视的因素之一。催化剂选择性影响因素主要是加氢裂化或氢解反应。因此,对催化剂脱氢选择性的改善既可通过调变金属组分的脱氢加氢性能,也可通过改变载体酸性进行。

A series of supported metal catalysts was prepared by impregenating support with different metal chloride solutions. The dehydrogenation of propane on these catalysts was carried out in a fixed bed reactor under reaction conditions of pressure 50kPa, temperature 560℃, LHSV 6h^(-1) ;and H_2/C_3H_8= 3(mole ratios).The results showed that the dehydrogenation of propane proceeded not only on supported platinum and palladium catalysts, but also on supported copper, catalysts. The activity for the dehydrogenation of propane increased with the increasing of copper content, and finally approached a steady value. The investigation of catalyst stability suggested that the interaction between metal and support plays an important role. The selectivity of these catalysts was affected mainly by hydrocracking reaction. Therefore, it may be improved by controlling the acidity of the support and/or the dehydrogenation-hydrogenation property of the metal component.For obtaining optimal activity and selectivity, we suggest that the optimal metal loadings should be 0.35～0.5w% for Pt, 0.5～1.0w% for Pd, and 5～10w% for Cu.