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Патент USA US2411996

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Dec. 3, 1946.
_
L. s. KASSEL
l 2,411,996
ME‘II’HOD FOR CATALYTIC CONVERSION _
Filed April I12, 1944
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Patented Dec. 3, 1946
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UNITED -STATES PATENT OFFICE
METH'OD FOR CATALYTIC CGNVERSION
Louis S. Kassel, Riverside. Ill.,v assignor toUni
versal Oil Products Company, Chicago, Ill., a
corporation of Delaware
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Application .4pm 12, 1944, serai No. 530,643
2 claims. (cl. 19e-_52)
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This invention relates to a method for conduct
ing catalytic conversions and more particularly
to a method for converting hydrocarbons by con
tact with suitable conversion catalysts.
The invention is concerned with a method of 5
conducting conversion reactions which may advantageously be employed in various processes
ior the conversion of hydrocarbons. Among the.
several processes to which the invention may be
applied are catalytic cracking of hydrocarbon oil, 10
catalytic reforming of gasoline boiling range ma:v
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generated catalyst from the lower end oi said
regeneration zone, introducing oxygen containing
gas under pressure to said regeneration zone and
contacting it therein with a moving bed oil cata
lyst to remove the contamination therefrom by
vcombustion andv employing the resultant flue gas
with no increase in pressure to transfer the re
generated catalyst from a point below said re
generation zone to a point above said conversion
zone, and to transfer the contaminated catalyst
from a~ point below said conversion zone to a
terials, catalytic aromatization of hydrocarbons,
point above said regeneration zone.
dehydrogenation of dehydrogenatable hydrocarbons,v and similar reactions for the conversion of
In a more limited embodiment the transfer o
catalyst by the Aflue gas from a point below the
hydrocarbons.
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15 regeneration zone to a point above the conversion
The invention although adaptable for use in
the above and similar reactions is especially suit-
zone and from a point below the- conversion zone
to a point above the regeneration’ zone is con'
able for use in the process for catalytically
cracking higher boiling hydrocarbon oils to form
ducted in substantially straight lines.
Suitable catalysts andlconditions for the vari
motor fuels of high antiknock rating.
.
20 ous conversion reactions which come within the
One object of the present invention is to provide a method of conducting catalytic conversions
scope of the invention are well-known in the art
~ and .will not be described in detail herein. How
in which catalyst, in the form of solid particles is
ever, to more clearly illustrate the advantages
passed successively through the conversion zone
which may be obtained from the use of the pres
and regeneration zone in continuously moving L5 ent invention the accompanying diagrammatic
beds.
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drawing will be explained in connection with a
Another object of the invention is to provide a
catalytic cracking process.
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catalytic conversion system, employing a moving
Referring to the drawing, numeral I denotes
catalyst bed in which the attrition of the catalyst
the reactor to which vaporous hydrocarbons are
and the erosion of processing equipment is held 3" charged through conduit 2 and valve 3. Reactor
to a minimum.
'
I when employed in a process for the cracking of
Another object of the invention is to provide
a method of conducting catalytic conversions by
a heavy Mid-Continent gas oil will be operated at
temperatures Within the range 0f about `’750 t0
means of which equipment of a given size may be
1050"- F. and at pressures of from about atmos
made to process a large Yquantity of charging 35 pheric to slightly superatmospheric.' The catalyst
material without sacrificing product yields or
employed may be formed of granular particles
quality.
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and may be composed of various natural occur
Another object of the invention is to provide a
ring clays or synthetic silica-alumina composites
catalytic conversion system in which the heat of
made, for example, by the process described in
regeneration supplies a substantial portion ofthe 40 U. S. Patent No. 2,229,353- BeSides Silica-alu
heat of reaction.
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mina, the catalyst may also include other oxides,
Another object of the invention is to provide
for example, oxides of magnesium, zirconium,fand
a system for the conversion of hydrocarbons
wherein the utility requirements are held to a
titanium. Very excellent results yhave been ob
tained employing a spherical shaped catalyst
minimum.
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45 made' by precipitating spheres of hydrated silica
In one embodiment the invention concerns a
method of converting hydrocarbons which comprises contacting said hydrocarbons in a zone
maintained at conversion conditions with a mov.. .
and impregnatlng them with alumina by soak~
ing them successively in an aqueous solution of
‘aluminum sulfate and in an alkaline precipitant.
The _spheres are then `washed, aged and dried.
ing bed oi catalyst, continuously introducing cat- 50
Although the preferred range of catalyst par
alyst to the upper end of said zone and _continuticle size is between about 11s to ?‘g inch average
ously removing contaminated catalyst from vthe
diameter the invention includes within its scope
lower end of said zone. continuously introducing
the use of larger and smaller size catalyst par
said contaminated catalyst to the upper end of
ticles. The main considerations in-the selection
a regeneration zone, continuously removing re- 55 of‘size are the allowable pressure drop through
2,41 1,996
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the catalyst beds in the various contacting vessels
and the ability of the carrying gases -to transport
the catalyst between the diñerent vessels.
The reaction products from reactor I are con
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from the system through valve 28 or it may be
directed by means of conduit 4I' and valve 42 to
conduit I8 to transport contaminated catalyst
withdrawn from the reactor to disengaging
chamber _I1 as has already been described. In
ducted through conduit 4 and valve 5 to suit
chamber 30 the catalyst particles fall by gravity
able separating and recovery equipment not
to hopper sectionßl wherefrom they pass by
shown. Catalyst is introduced to reactor I by
means of conduit 8 into reactor I,_thus complet
means of conduit G and withdrawn therefrom by
, ing the- cycle. `Chamber 30 like chamber I1 may
conduit- 1. Within the lower portion'of the re
actor is placed a cone-shaped member 8 which 10 be provided with a baille 32 which functions to
may consist oi" a perforated plate or screen '
which serves as a distribution means for the'in
substantially prevent catalyst parties from be
ing withdrawn from the chamber by means of
conduit 35.
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coming reactant stream. _Inlet condut 8 for sup
The pressure in reactor I is ‘normally higher
plying the regenerated catalyst to the reactor ex
tends some distance below the upper head of the 15 than in disengaging chamber 30. In order to
prevent reaction products from iiowing up
reactor to provide a separation space for the re
through conduit 8 into chamber 30 and ultimately
action products leaving the' catalyst bed.
being lost with the spent regenerating- gas, a
Below reactor I and connected thereto by con
stream of splitting iluid is provided. This stream. '
duit 1 is stripper .9 through which the catalyst
particles are passed in contact with a suitable 20 enters conduit 6 by valve 3_4 and line 33. The
quantity of the> splitting stream is regulated so
stripping iluid, such as steam, ilue gases, or
that the pressure at the junction of line 33 and
other inert material -to remove vaporizable con
conduit 8 is higher than that in reactor I. The
taminating materials‘from the catalyst to pre
splitting stream therefore fiows'away from the
vent their loss by combustion in the regeneration
zone. Stripper 9 is similar in constructionto 25 junction in both directions, and provides a pos
itive seal against mixing of reaction products and
reactor I and is supplied with a stripping iluid
regeneration gas. This splitting stream may be
introduced by means of conduit _ I0 and valve
Il. 'I‘he stripping fluid plus any materials ,re
any inert gas or vapor, such as nitrogen, helium _
or steam. As a practical matter, steam is pre
moved from the catalyst'is withdrawn through
conduit. I2 and valve I3 and directed to suitable 30 ferred on economic grounds.
The following discussion of pressure gradients
recovery equipment not shown. The“ stripped
is supplied in order to clarify the method of op-catalyst is withdrawn from the bottom of strip
per! by means of conduit I4 controlled by valve
eration. The air which enters the process by
-or adjustable orifice I5. The catalyst passing
conduit 25 and ultimately leaves as regenerating
through valve I5 is commingled in conduit I8 35 gas by conduit I8 can take any one 0f three paths
through the plant. It can flow up through re
with a carrying gas produced as> will hereinafter
_generator 22 and conduit 2'I into chamber I1 and
be described, and passes therewith into disengag
. thence 'out' through line I8. It can ilow through
ing chamber I1. The catalyst particlesare sepa
the lower conical section of regenerator 22 and '
rated from the carrying gas in chamber I1, the
gas leaving the system through conduit I8- and 40 the distribution section 23 into conduit 28 and
the catalyst particles falling to the bottom or
thence by, valve 29, conduit 39, chamber 30, con- ‘
' hopper section I9 of the disengaging chamber.
duits 35,- 4I and I8 and chamber I'I to line I8. Or
it can take the desired path through regenerator
A baille plate 20 is provided in disengaging cham
ber I1 to prevent catalyst particles from entering
22, conduit 21, conduits 31 and 39, chamber 30, ~
conduit I8 and being removed thereby from the
conduits 35, 4I and I5 and chamber I1 to line I8.
system. 'I'he contaminated catalyst flows from
The amount of air which takes the ilrst undesired
path is made small by making conduit 2I of
chamber I1 by means of conduit 2| into regener
. great enough height and small enough diameter
ator22. Regenerator 22 is similar in construc
' so that the frictional pressure drop of gas flow`
. tion to the reactor and stripper vessels being pro
vided with a distribution member 23 and a sepa 50 through the catalyst mass in this conduit pro
ration space 24 for emuent gases. Air is sup- ’ ' vides an effective ilow resistance. 'I'he quantity
of air which takes the second undesired path is '
plied to the regenerator by means of conduit 25
likewise made small by provision of suilicient
' controlled by valve 28.
resistance infconduit 28. The' major part 0f the
The temperature maintained~ >in regenerator 22
will be higher than the temperature maintained 55 air stream 4is therefore constrained to take the
in reactor I. The magnitude of this difference
A portion of the stripping fluid will likewise
will vary with the charging stock to be convert- v
flow down through conduit I4, and here again
ed and the particular product which may bede
this undesirable tlow is minimized by proper de
sirable. In general, however, this differential
'
will vary from about 50 to 150° F. The air sup 60 sign of conduit- I4.
Any of these undesired ñows could be com
plied to regenerator 22- removesthe contamina
pletely prevented by the use of a splitting stream
tion from the catalyst by combustion and the
resultant flue gas is withdrawn from the regen
such as is shown in conduit 8. In most cases,
erator by means of conduit 21 and maybe di
however,- _this would not be particularly advan
verted to conduits I 8 and 39 respectively by 65 tageous.
From the drawingit can readily be ~'seen that f
means of valve 40 and conduit 31 and valve 38.
the only conduits carryin'g‘high velocity catalyst
The regenerated catalyst is removed from the
regenerator by means .of conduit 28 controlledparticles conduct them in a' substantially straight
by valve or adjustable orifice 29.l The catalyst
line flow which, of course, will limit erosion of
passing through valve 29 is commingled with ilue 70 the line and attrition of the catalyst particles to
Vgas passing through' conduit 39 and is transport
ed thereby to catalyst disengaging chamber 35
, In order to further illustrate the utility of the
wherein the catalyst is separated from the ñue
-process the following example is included in this
specification:
.
gas. The ñue gas is withdrawn from chamber
88 by means of conduit 35 and maybe removed 75 ^ A 31.2° API heavy Mid-Continent gas oil is
desired
path.
a minimum. _
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2,411,996
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vaporized and introduced to reactor I which is
zone maintained at combustion temperature to
maintained at an average temperature of 975° F.
burn contaminants from the catalyst particles,
The catalyst used is a spherical shaped silicasupplying regenerated catalyst particles by grav~
alumina composite having a particle size oi' about
ity to the upper portion of the reaction zone from
11g inch diameter. `The oil is charged at a rate 5 a separating zone disposed lat a higher elevation
equivalent to a weight hourly space velocity of
than the reaction and regenerating zones, sup
` 8.5 (8.5 pounds of oil per pound of catalyst in
. plying contaminated catalyst particles by gravity
the reaction zone) and the catalyst is circulated
to the upper portion of the regenerating zone
at a catalyst to oil weight ratio ‘of 3.2 (3.2 pounds
of catalyst entering the reaction zone to each
pound of'oil).
from a second separating zone disposed at a
The resultant product contains a
higher elevation than the reaction and regener
ating zones, removing contaminated catalyst
motor fuel having a clear ASTM octane num
ber by the motor method of 82.5. The yield of '
this gasoline on a once through basis is 38.8 vol
urne per cent of the gas oil charged. The con 15
with‘drawn regenerated catalyst particles up
version obtained based on the per cent of dis
appearance of the gas oil charged is 54.7.
wardly to the vfirst-'named separating zone in sus
pension in combustion gases formed in the re
from the lower portion of the reaction zone, re
moving regenerated catalyst from the lower por
tion of the regenerating zone, transporting the
From this example it can readily be seen that
generating zone, separating the regenerated par
the present invention oiïers a process by which
ticles ‘from the combustion gases in said iìrstu
large quantities of charging material may be conf 20 named separating zone, suspending in at least
verted to a highly desirable product in relatively
`a portion of the thus separated combustion gases
small and inexpensive equipment. .
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the contaminated catalyst removed from the
lower portion, of' the reaction zone, passing the
resultant suspension upwardly into saidv second
separating zone and therein separating the con
taminated catalyst from the combustion gases.
2. The process as deñned in claim 1 further
characterized in that the regenerating zone is
maintained under a pressure such that the pres
Also by employing the present invention veryv
e?cient and economical transfer of catalyst be»
tween the various processing' zones is accom
plished, the incoming regenerating air under
moderate pressure supplying all the necessary
lifting power.
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' I claim as my invention:
1. A conversion process which comprises con
tacting hydrocarbons with subdivided solid cata-=
30 sure of the combustion gases'kiischarging there
viyst in a reaction zone maintained under con
version conditions, simultaneously passing an'
oxygen-»containing gas through a mass oi' con
taminated catalyst particles in a regenerating 35
from is sumcient to overcome the flow resistance
in_said‘ transportation „of the catalyst, the latter
being transported as aforesaid under the pres
sure of the regenerating zone.
.
LOUIS S. KASSEL.
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