Patent GB-732825-A (GB)
Title: Improvements in or relating to fluidised hydroforming process
IPC: C10G35/14
Filed: 1953-03-30
Abstract: <PICT:0732825/IV (b)/1> A fluidized process for hydroforming naphthas, wherein a dense fluidized stream of spent catalyst particles is continuously withdrawn from a reaction zone, regenerated under oxidizing conditions and returned to the reaction vessel, is characterized in that after entering the reaction vessel, but prior to entering the reaction zone, the regenerated catalyst particles are contacted in a stripping zone above the level of the reaction zone countercurrently with a rising stream of stripping and reducing gas whereby the regenerated catalyst particles are further activated and thereafter enter the said reaction zone, and the stripping and reducing gas is at all times above the level of the said reaction zone.  Spent catalyst from fluidized bed 3 is withdrawn through line 8 via stripper 10 or an external stripper and conveyed through line 19 as a dense fluidized stream to the regenerator.  The regenerated catalyst is withdrawn from bed 22 through line 29 and passed downwards through a U-bend seal 30 which extends below bed levels 4 and 23 so as to prevent any back mixing of gases or catalyst from either reactor or regenerator. The catalyst enters the reactor at point 35 and flows downward through a stripping zone 32, formed by a baffle 33 extending below the bed level 4.  A stripping and reducing gas, which may be recycle gas, enters zone 32 at a lower level which is always above bed level 4.  Suitable baffles 38 improve the gas-solids contact and baffle 39 directs the regenerated catalyst into bed 3 while minimizing the access of reactant vapours to the stripping zone. The extent of reduction of the regenerated catalyst is determined by the amount of pretreating gas introduced and the contact time of gas and solids in the stripping zone.  This latter is determined by the extent of baffle 33 above the gas inlet and is desirably between about 5 to 20 seconds.  The treatment of the regenerated catalyst in zone 32 causes a rise in temperature of about 50 DEG  F., supplying heat to the hydroforming reaction and enabling a lower regeneration temperature to be used.  The preferred catalyst comprises a Group VI metal, particularly molybdenum.ALSO:<PICT:0732825/III/1> A fluidized process for hydroforming naphthas, wherein a dense fluidized stream of spent catalyst particles is continuously withdrawn from a reaction zone, regenerated under oxidizing conditions and returned to the reaction vessel, is characterized in that after entering the reaction vessel, but prior to entering the reaction zone, the regenerated catalyst particles are contacted in a stripping zone above the level of the reaction zone countercurrently with a rising stream of stripping and reducing gas whereby the regenerated catalyst particles are further activated and thereafter enter the said reaction zone, and the stripping and reducing gas is at all times above the level of the said reaction zone.  Spent catalyst from fluidized bed 3 is withdrawn through line 8 via stripper 10 or an external stripper and conveyed through line 19 as a dense fluidized stream to the regenerator.  The regenerated catalyst is withdrawn from bed 22 through line 29 and passed downwards through a U-bend seal 30 which extends below bed levels 4 and 23 so as to prevent any back mixing of gases or catalyst from either reactor or regenerator. The catalyst enters the reactor at point 35 and flows downwards through a stripping zone 32, formed by a baffle 33 extending below the bed level 4.  A stripping and reducing gas, which may be recycle gas, enters zone 32 at a lower level which is always above bed level 4.  Suitable baffles 38 improve the gas-solids contact and baffle 39 directs the regenerated catalyst into bed 3 while minimizing the access of reactant vapours to the stripping zone. The extent of reduction of the regenerated catalyst is determined by the amount of pretreating gas introduced and the contact time of gas and solids in the stripping zone.  This latter is determined by the extent of baffle 33 above the gas inlet and is desirably between about 5 to 20 seconds.  The treatment of the regenerated catalyst in zone 32 causes a rise in temperature of about 50 DEG  F., supplying heat to the hydroforming reaction and enabling a lower regeneration temperature to be used.  The preferred catalyst comprises a Group VI metal, particularly molybdenum.