Dehydrogenation of Alkyl Aromatics

Abstract

Dehydrogenation of a reactor system of one or more vertically oriented flow reactors equipped with a system for introducing a catalyst extender into the inlet of the reactor. A vertically oriented radial flow reactor comprises inner and outer reactor tubes having perforated wall members extending longitudily of the reactor and defining an annulus containing a dehydrogenation catalyst. A supply line to the reactor is equipped with a rotation vane. An injection nozzle comprising a coaxial flow tube extends into the supply line downstream of the vane. The coaxial flow tube has an interior chamber and an annular chamber surrounding the interior chamber and extending into the supply line along with the interior chamber. The interior chamber is connected to a catalyst extender source and the annular chamber is connected to a source of a carrier gas which is effective to disperse the extender within feedstock flowing into the reactor.

1 - 18 . (canceled) 
     
     
         19 . A method for the production of styrene by the catalytic dehydrogenation of ethyl benzene in a radial flow dehydrogenation reactor comprising:
 a) supplying an ethyl benzene containing feedstock into the bottom of a radial flow dehydrogenation reactor having a longitudily extending annular catalyst bed containing a catalyst for the dehydrogenation of ethyl benzene to styrene;   b) operating said radial flow dehydrogenation reactor under temperature and pressure conditions effective to cause the dehydrogenation of ethyl benzene to styrene in the presence of said dehydrogenation catalyst;   c) flowing said feedstock to the inlet of said radial flow dehydrogenation reactor through a u-shaped flow path in which said feed stock flows in a substantially vertical direction followed by a flow in a generally horizontal direction and subsequent flow in a generally vertical direction opposed to the initial direction of flow into said reactor and;   d) introducing a catalyst extender into said feed stock within said u-shaped flow path and flowing said catalyst extender along with said feed stock through said annular catalyst bed within said radial flow reactor.   
     
     
         20 . The method of  claim 19  further comprising within said u-shaped flow path passing said feedstock over a rotation vane comprising a plurality of turning sections which impart rotational flow to said feedstock within said flow path and wherein said catalyst extender is introduced into said feedstock within said u-shaped flow path at a location downstream of said rotation vane section. 
     
     
         21 . The method of  claim 20  wherein said catalyst extender is introduced into said feedstock through a concurrent flow injection nozzle in which said catalyst extender flows through a central path of said injection nozzle and further comprising injecting a carrier gas into an annular path of said injection nozzle so that said carrier gas and said catalyst extender are introduced into said flow stock. 
     
     
         22 . The method  claim 19  wherein said catalyst extender is a potassium salt of a C 2 -C 6  carboxylic acid and said carrier gas is methane or ethane. 
     
     
         23 . The method of  claim 22  wherein said catalyst extender is potassium acetate. 
     
     
         24 . The method of  claim 20  wherein said catalyst extender is introduced into the bottom of said reactor through a said u-shaped flow path having a first leg in a general vertical downward direction and a second leg in an opposed general vertical upward direction flowing into said reactor. 
     
     
         25 . The method of  claim 24  wherein said first leg incorporates said rotation vane section imparting a rotational flow to said feed stock and said flow path.