Kill-gas introduction to a fluidized bed reactor containing chromium oxide catalyst

摘要

The present invention relates to a process for stopping an olefin polymerization which is carried out in a low pressure gas phase reactor, which process comprises introducing an effective quantity of deactivating agent into the reactor, characterized in that the olefin polymerisation is carried out using a chromium oxide catalyst and in that the deactivating agent is selected from oxygen, ammonia, water and carbon monoxide and is introduced over a relatively short period of time. The deactivating agent is preferably introduced into the polymerization reactor in a quantity such that in the reactor the weight ratio of the deactivating agent to the catalyst is at least 0.001.