Method of operating a dehydrogenation reactor system

A method of operating a dehydrogenation reactor system, said method comprises:

• providing said dehydrogenation reactor system, which comprises a dehydrogenation reactor defining a reaction zone and containing therein a dehydrogenation catalyst;
• introducing a dehydrogenation feed into said dehydrogenation reactor operated under dehydrogenation reaction conditions such that said dehydrogenation catalyst is at a first temperature;
• terminating the introduction of said dehydrogenation feed into said dehydrogenation reactor;
• introducing a carbon dioxide-containing cooling gas, comprising carbon dioxide, into said dehydrogenation reactor for a time period sufficient to provide a cooled dehydrogenation catalyst having a temperature that is below said first temperature;
• and
• terminating the introduction of said carbon dioxide-containing cooling gas into said dehydrogenation reactor.

A method, comprising:

• contacting a dehydrogenation feed with a dehydrogenation catalyst under dehydrogenation reaction conditions thereby providing said dehydrogenation catalyst that is at a first temperature;
• terminating the contacting of said dehydrogenation feed with said dehydrogenation catalyst;
• contacting said dehydrogenation catalyst with a first cooling gas, comprising steam, for a first time period sufficient to reduce the temperature of said dehydrogenation catalyst to a second temperature that is lower than said first temperature but greater than the condensation temperature of said first cooling gas;
• terminating the contacting of said dehydrogenation catalyst with said first cooling gas;
• and
• contacting said dehydrogenation catalyst with a second cooling gas, comprising carbon dioxide, for a second time period sufficient to reduce the temperature of said dehydrogenation catalyst to a third temperature that is lower than said second temperature.

A method of operating a dehydrogenation reactor system, said method comprises:

• providing said dehydrogenation reactor system, which comprises a dehydrogenation reactor defining a reaction zone and containing therein a dehydrogenation catalyst;
• introducing a dehydrogenation feed into said dehydrogenation reactor operated under dehydrogenation reaction conditions such that said dehydrogenation catalyst is at a first temperature;
• terminating the introduction of said dehydrogenation feed into said dehydrogenation reactor;
• introducing a first cooling gas, comprising steam, into said dehydrogenation reactor for a first time period sufficient to reduce the temperature of said dehydrogenation catalyst to a second temperature below said first temperature but greater than the condensation temperature of the first cooling gas;
• terminating the introduction of said first cooling gas into said dehydrogenation reactor;
• and
• introducing a second cooling gas, comprising a major portion carbon dioxide, into said dehydrogenation reactor for a second time period sufficient to reduce the temperature of said dehydrogenation catalyst to a third temperature below said second temperature.