| 摘要 |
The present invention concerns a heterogenic catalyst suited to the metathesis reactions of hydrocarbons in particular. Such a catalyst includes an inorganic oxide support, typically consisting of gamma -alumina, having rhenium oxide absorbed onto its surface. The catalyst in accordance with the invention is prepared by vapourizing a precursor of rhenium, preferably rhenium heptoxide, preferably at a temperature of at least 160 DEG C, and routing the vapour into a reaction chamber where they are brought to interaction with the support material. The temperature of the support material is kept above the condensation temperature of the vapour and simultaneously sufficiently high so as to attain the thermal activation energy level necessary for the generation of bonds between the rhenium oxide and the support material. According to the invention, the process is carried out preferredly within a temperature range of approx. 160...500 DEG C. The rhenium oxide precursor is introduced in vapour phase in an amount, which is at least equal to or, preferably, in excess of the number of available binding sites on the support material surface. The activity of a catalyst even with a very low content of catalytic metal species is as high as the activity of a catalyst of appreciably higher content of rhenium that has been prepared by the methods of conventional technology. |
