Patent GB-730223-A (GB)
Title: Improved fluidized hydroforming process
IPC: C10G35/14
Filed: 1952-11-21
Abstract: <PICT:0730223/IV (b)/1> <PICT:0730223/IV (b)/2> In a process of hydroforming hydrocarbons using a fluidized catalyst, continuously withdrawing a stream of catalyst to a regeneration zone where carbon is burnt off, treating the regenerated catalyst with hydrogen-rich gas, and recycling to the hydroforming zone, the hot regenerated catalyst is cooled with a second stream of catalyst from the hydroforming zone prior to the treatment with hydrogen.  The amount of said second stream is sufficient to absorb the heat of reduction and prevent a rise of temperature of the regenerated catalyst on treatment with hydrogen.  The regenerated catalyst may be mixed with spent catalyst in a separate hydrogen treatment vessel or the mixture carried by a stream of hydrogen-rich gas to the main reactor. Alternatively, indirect heat exchange may be used, preferably using a reactor having at least two vertically spaced beds connected by downcomers, catalyst being taken from the upper bed to the regenerator and regenerated catalyst recycled to the lower bed.  The heated reactor catalyst is recycled to the upper bed whereby a higher temperature is maintained therein, e.g. 900-950 DEG  F., compared with 875-900 DEG  F. in the lower bed.  Regeneration may be at 1050-1200 DEG  F., the regenerated catalyst then being cooled to below 1050 DEG  F. prior to the hydrogen treatment.  Gaseous products of the latter which contain water vapour are preferably separated from the catalyst to prevent deleterious action thereon under hydroforming conditions.  For direct mixing, reactor 10, Fig. 1, is provided with conduit 18, whereby spent catalyst is taken to a stripper 19, and thence to regenerator 30.  Regenerated catalyst overflows into a stripping cell formed by conduit 37 which connects with conduit 40 and transfer lines 42, 48. Catalyst from the reactor flows by conduits 43, 44 to line 42 where mixing with regenerated catalyst occurs.  The hydrogen-containing gas is separated in 49, and catalyst returned by line 51.  For indirect heat exchange, reactor 110, Fig. 2, is divided to contain two fluidized beds 116, 117. Catalyst withdrawn from the upper bed passes through stripper 121 and U-line 124 to regenerator 130.  Regenerated catalyst is taken by line 136 to heat exchanger 145 where it is cooled by catalyst withdrawn from the reactor by line 137 and passing via stripper 138 and U-line 141 through the exchanger back to the reactor. The cooled, regenerated catalyst passes via line 147, where it is treated with hydrogen-rich gas fed by conduit 148, to the lower bed 116.  The feed may be virgin, cracked or Fischer-Tropsch naphtha and is preheated either alone or with recycle gas to as high a temperature as possible, while avoiding degradation.ALSO:<PICT:0730223/III/1> <PICT:0730223/III/2> In a process of hydroforming hydrocarbons using a fluidized catalyst, continuously withdrawing a stream of catalyst to a regeneration zone where carbon is burnt off, treating the regenerated catalyst with hydrogen-rich gas, and recycling to the hydroforming zone, the hot regenerated catalyst is cooled with a second stream of catalyst from the hydroforming zone prior to the treatment with hydrogen.  The amount of said second stream is sufficient to absorb the heat of reduction and prevent a rise of temperature of the regenerated catalyst on treatment with hydrogen. The regenerated catalyst may be mixed with spent catalyst in a separate hydrogen treatment vessel or the mixture carried by a stream of hydrogen-rich gas to the main reactor. Alternatively, indirect heat exchange may be used, preferably using a reactor having at least two vertically spaced beds connected by downcomers, catalyst being taken from the upper bed to the regenerator and regenerated catalyst recycled to the lower bed.  The heated reactor catalyst is recycled to the upper bed whereby a higher temperature is maintained therein, e.g. 900-950 DEG  F. compared with 875-900 DEG  F. in the lower bed. Regeneration may be at 1050-1200 DEG  F., the regenerated catalyst then being cooled to below 1050 DEG  F., prior to the hydrogen treatment.  Gaseous products of the latter which contain water vapour are preferably separated from the catalyst to prevent deleterious action thereon under hydroforming conditions.  For direct mixing, reactor 10, Fig. 1, is provided with conduit 18, whereby spent catalyst is taken to a stripper 19, and thence to regenerator 30. Regenerated catalyst overflows into a stripping cell formed by conduit 37 which connects with conduit 40 and transfer lines 42, 48. Catalyst from the reactor flows by conduits 43, 44 to line 42 where mixing with regenerated catalyst occurs.  The hydrogen-containing gas is separated in 49, and catalyst returned by line 51.  For indirect heat exchange, reactor 110, Fig. 2, is divided to contain two fluidized beds 116, 117.  Catalyst withdrawn from the upper bed passes through stripper 121 and U-line 124 to regenerator 130. Regenerated catalyst is taken by line 136 to heat exchanger 145 where it is cooled by catalyst withdrawn from the reactor by line 137 and passing via stripper 138 and U-line 141 through the exchanger back to the reactor.  The cooled, regenerated catalyst passes via line 147, where it is treated with hydrogen-rich gas fed by conduit 148, to the lower bed 116.  The feed may be a virgin, cracked or Fischer-Tropsch naphtha and is preheated either alone or with recycle gas to as high a temperature as possible while avoiding degradation.