| 摘要 |
<PICT:0832425/III/1> Catalyst for use in a fluidized bed reactor is treated by contacting the catalyst with a flame while suspended in a finely-divided state. The catalyst may be regenerated by the treatment, or it may be fresh catalyst. Catalyst fluidized in a chamber 14 (Fig. 1) is treated by a flame emanating from a burner 10, air or oxygen being introduced by a pipe 44. Catalyst passing overhead is recovered by cyclone separators 20 and 24 and either returned to chamber 14 by a pipe 34, or discharged to a drum 36. Catalyst is introduced into the apparatus by a pipe 50 through the cyclone separators. In another embodiment the catalyst is introduced at a point near the burner. The catalyst may be silica-alumina, sand, silicon carbide, clay, diatomaceous earth, aluminium silicate, silica, alumina, or aluminium-magnesium silicate, and is used in the reaction of ethylene dichloride and chlorine to obtain tetrachlorethylene.ALSO:Chloro-substituted ethylenes are produced by chlorinating and dehydrochlorinating ethylene dichloride in a fluidized catalyst bed in which the catalyst is sand, silicon carbide, clay, diatomaceous earth, synthetic aluminium silicate, silica, alumina gel or natural aluminiummagnesium silicate which has been contacted with a flame while fluidized. Degraded catalyst is removed from the beds and replaced with more catalyst which has been activated or regenerated by being maintained in a fluidized state in contact with a flame. In examples, tetrachloroethylene is obtained using a silicaalumina catalyst. |
