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Патент USA US2405959

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Aug. 20,‘
TREATING
. I P. E. HYDROCARBON
KUHL ETAL
FLUID
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Filed Aug. 24, 1940 Y
FEAICTIGNA’TING
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Patented Aug. 20, 1946
2,4053%
UNITED STATES PATENT OFFICE
_
2,405,959
TREATING HYDROCARBON FLUID
Paul E. Kuhl, Madison, and Robert M. Shepard
son, Cranford, N. J., assignors to Standard Oil
Development Company, a corporation of Dela
ware
Application August 24, 1940, Serial No. 353,998
15 Claims. (01. 196-—52)
1
2
.
This invention relates to the conversion or '
cracking of hydrocarbons in the presence of a
catalyst and more particularly relates to the con
grammatio showing of one form of apparatus
adapted for carrying out our invention.
7
Referring now to the drawing, the reference
character It designates a line through which the
version of relatively heavy hydrocarbon mixtures
by mixing the particles of solid catalyst with the
relatively heavy hydrocarbons to form a liquid
mixture. or slurry and then passing the resulting
hydrocarbon oil to be converted is preferably a
slurry through a reaction zone.
relatively heavy ,oil, such as East Texas gas oil,
hydrocarbon oil isiorced by means of pump l2
and introduced into a mixer or the like It.
The
but other hydrocarbon oils may be used. Solid
It is'known in the catalytic cracking of hydro
carbons to heat and vaporize the hydrocarbons 10 catalyst in powdered form is introduced into the
mixer 14 through line Hi. The catalyst may be
and then pass the hydrocarbon vapors over sta
any active cracking catalyst such as active nat
tionary beds of catalyst in a catalyst tower or
ural or synthetic clays, Super Filtrol, synthetic
reaction zone. While these prior art processes
gels containing silica and alumina, etc. Super
may be used to produce gasoline, we have found
that our invention has distinct advantages over 15 Filtrol is an adsorptive material produced by the
acid treatment of clay. We have given some
processes usingthe ?xed catalysts.
catalysts by way of example, but our invention
‘According to our invention, the catalyst is
mixed in any suitable manner with relatively
is not to be restricted thereto as many other
heavy hydrocarbons or other hydrocarbon mix
cracking catalysts may be used. The mixer. i4 is
tures, such as gas oil for example, to form a 20 preferably provided with a mixing device (not
slurry.
The catalyst in powdered form is mixed
with the liquid hydrocarbons so as to form a
liquid mixture containing the catalyst in suspen
sion. A large quantity of catalyst per volume of
hydrocarbons is used as compared to previously
known methods usingcatalysts suspended in oil.
The slurry or mixture of catalyst and liquid hy
drocarbons is then passed through a reaction zone
wherein the hydrocarbons are heated to reaction
temperature. By using a slurry, the relatively
small solid catalytic particles are substantially
shown) for mixing the hydrocarbon oil and solid
catalyst particles introduced into the mixer M
in order to maintain the catalyst particles in sus
pension in the oil.
Relatively large amounts of catalyst per Volume
of oil are used. When thecatalyst is exceedingly
active, such as fresh Super Filtrol, about 35-40
Weight per cent on the hydrocarbon oil is pref
erably used. This amount may be varied, and
30 We are not tobe limited to this speci?c percentage
rangegiven. If the catalyst is not as active as
the fresh SuperFiltrol or after the Super Filtrol
or other catalyst has been regenerated a number
of times,.1arger quantities of catalyst will be re
bons are contacted with catalyst particles as'the
catalyst and hydrocarbons are passed through 35 quired. In such cases where the catalyst is rela
tively inactive, about 90 to 100. weight per cent
the conversion zone to obtain a greater yield of
of catalyst on the oil may be used. The weight
desired products. Another feature of our inven
uniformly distributed throughout the hydrocar
bon liquid and substantially all of the hydrocar
'
tion comprises separating the catalyst particles
as a dry powder from the reaction products rather
than as a slurry. In our invention, large quan
titles of catalyst with respect to the hydrocar
bons to be cracked are used. If relatively small
amounts of catalyst per oil are used, the process
is not suitable for catalytic cracking of hydro
carbons because of poor yields.
In vusing our invention with a relatively large
amount of catalyst per volume of hydrocarbon
per cent of catalyst on the oil may vary from
about 35% to about 100%.
The mixture or slurry of catalyst and oil are
40. withdrawn
from the bottom of mixer M and
passed through line 20 by pump 22, 'and then
passed through a heating coil 24 in heater 26
wherein the mixture is heated to an elevated tem
45 perature of about 800 to 950° F. and under pres
sure from about atmospheric to about 350.1bs.
per square inch.
Under these conditions, con
version of the hydrocarbon oil to lower boiling
oil and passing the mixture through a conver
hydrocarbons ‘is. effected. The hydrocarbon oil
sion zone wherein it remains for a time su?icient
is vaporized in the heater in the presence of the
to effect the desired extent of conversion, it has 50 catalyst particles and substantially all of the
been found that improved product distribution
hydrocarbon vapors are contacted by the cata
results as compared to results obtained by using
lyst particles, and in this way maximum conver
processes utilizing .?xed catalysts. .Also, larger
sion of the higher boiling hydrocarbons to lower
yields of cycle gas oil are obtained, and the cycle
55 boiling hydrocarbons results. The distribution
gas oil .is of a better quality than that obtained
of the catalyst particles in the hydrocarbon oil
when using stationary or ?xed catalysts. Our
vapors in. the reaction zone is obtained by ?rst
invention will be hereinafter described in greater
mixing the catalyst with the liquid hydrocarbon.
detail.
The hydrocarbon vapors and catalyst particles
In the drawing, the ?gure represents ,a dia— 60 are maintained in the reaction zone for a rela
2,405,959
3
4
tively short period of time but su?icient to effect
maximum conversion of the hydrocarbon vapors
to desired product. Other types of reaction zones
fractionating tower 48 wherein the vapors are
may be used such as reactors of a delayed settling
type wherein the larger catalyst particles remain
in the reaction zone for a longer period of time
than the smaller catalyst particles. Also an un
heated reaction vessel following the reaction zone
may be employed. The products of conversion ‘in
vapor form, together with the catalyst particles,
fractionated to separate a light hydrocarbon
fraction containing gasoline constituents from a
relatively heavy condensate oil. The condensate
oil is withdrawn from the bottom of. the frac
tionating tower 48 and passed through line 52 by
pump 54. The condensate oil may be recycled to
the line H) and admixed with the feed or hydro
carbon oil being introduced into the mixer 14 or
10 may be withdrawn at 53. In some cases, it may
leave the reaction zone or heating coil 24 through
line 28 and are introduced into the upper portion .
be desirable to withdraw the recycle stock as a
side stream from tower 48 over a small quantity
of bottoms so as to reduce coking in the catalytic
of a separator 30 which may be a cyclone sepa-,
cracking step, the bottoms being withdrawn from
‘rator or any other suitable apparatus for sepa
rating vapors from solid catalyst particles. In 15 the system.
i
this way a dry separation of catalyst particles is
The vapors passing overhead from the frac
obtained. The products of reaction leaving the
tionating tower 48 pass through line 58 and con
denser 60 for condensing normally liquid hydro
reaction zone or coil 24 are at a relatively high
temperature and they are not cooled, so that a
carbons, and the cooled and condensed hydro;
dry separation between vapors and solids takes
carbons and water are introduced into a gas
place in the separator 30.
v
'
’
separator 62 for separating gases from normally
liquid hydrocarbons within the gasoline boiling
During the conversion in the reaction zonev or
range and water. The gases are removed by
coil24, carbonaceous material‘ or the like settles
or deposits on the catalyst particles, and it is
means of line 63, the normally liquid hydrocar
necessary to regenerate the catalyst particles by
bons are withdrawn from the lower portion of the
separator 62 by lines 64 and 65. The Water is
burning oiT the carbonaceous deposits before re
using the catalyst. ‘ The separator 30 provides a
removed from the bottom of separator 62 through
line 66. Preferably, a portion of the normally
means for separating the reaction products in
liquid hydrocarbons is passed through line ‘I0 by
vapor form from solid catalyst particles together >
pump 12 and. returned to the upper portion of
with any carbonaceous deposit
The separator 30 is provided in its upper por
the fractionating tower 48 as re?ux for the tower.
Data are presented below showing the results
tion with a downwardly extending tubular mem
obtained by mixing a gas oil with powdered Super
ber 32, which extends below the point of intro
duction of the reaction products into the sepa
Filtrol as catalyst to form a. slurry, and this slurry
rator 30, so that the reaction products and solid 7 ' is then passed through the reaction zone or coil.
catalyst particles are given a rotary motion and
Data are also presented for purposes of compari
passed horizontally and downwardly before the
son which were obtained by passing gas oil vapors
vapors'may pass ‘upwardly through the interior of
over a stationary or ?xed bed catalyst. The last
the tubular exit member 32 in the separator 30.
mentioned data are correlated with the powdered
The solid particles; together with any tar or at moving catalyst for purposes of easier compari
carbonaceous material, fall downwardly in the
son. Using the catalyst-oil slurry improved prod
separator 30 and strike the inclined 'ba?le mem
uct distribution over ?xed catalyst operation was
ber 34 from which the catalyst and solid particles
obtained as will be seen from an inspection of the
pass to the next and lower inclined baffle member
36 and then to the last inclined ba?le member 38. 74:5
following data.v
From the ‘baffle member 38, ‘the solids and
catalyst particles fall into the bottom portion 40
of the separator 30 from which they are with
drawnithrough outlet 42 in any desired manner.
The catalytic particles with their carbonaceous
Powdered vs. Fixed Catalyst Operation on 33.3"’
deposits after removal are regenerated in any
correlation
A. P. I. East Texas Gas Oil
Powdered moving
6 a yst
suitablemanner as by burning off the carbona
Operation
ceous deposits with diluted air or other oxygen
containing gas, care being taken to prevent over
heating of the‘ catalyst particles.
'
Catalyst
Powdered Super Pilled Super
The regen- 3'
erated catalyst particles are then returned to the
mixing chamber M by means of line IE or a
Operating Conditions:
separate line, if desired. While we have shown
Pressure, #/sq. in. gauge_____._
three ba?le members in the separator 30, it is
Temperature, °F ____________ ._
to be understood that these are by way of ex to?)
Dry1 catalyst, wt. percent on
ample. only, and the number of ba?le members
may be varied as desired.
- In order to assist in removing residual oil from
thecatalyst particles, steam, hydrogen or other
heated gas is preferably introduced into the lower 7
portion of the separator by means of valved line
44.
The steam or other heated gas passes up
.wardly
countercurrent
to
the
down-falling
catalyst particles, and in this way residual oil is
vaporized and removed from the catalyst 70
particles, and the resulting vapors are mixed with
the vaporized reaction products which leave the
top of the separator 30 by means of the tubular
member 32 and line 46.
The hydrocarbon vapors are introduced into a 75
catalyst
o
13"1 . rol
_________________________ __
Steam (A), wt. percent on oil.
Contact time, seconds _______ ._
Coil velocity, ft./scc ___. __ ____ __
Feed rate, vol. cold oil/cat.
vol./hr ______ .r ____________ __
Cycle length, minutes (B).____
Yields on feed:
Gasoline, 10)? R. V. P., per
cent vol
,
Excess butane, percent v01
Cycle gas 01], percent vol
Dry gas, percent wt-..“
Coke, percent wt ____________ __
Gasoline inspections, l0# B. V. P.:
A. S. T. M. octane No__
Percent at 212° F________
_ Gravity cycle gas oil, “A. P. ___-
(A) Water in undried catalyst employed.
(_B) At catalyst age of 200 cycles.
Fil tro l
2,405,959
5
In obtaining thesedata with the oil slurry, the
6
carbons tolower‘boiling hydrocarbons "which
catalyst was Super Filtrol and was fresh and very
comprises‘ mixing a- gas oil with ‘about 38%--'by
weight of the oil of a solid powdered highly ac
‘Super Filtrol is used, the quantity of catalyst per
tive clay/cracking catalyst in a mixing'zone-to
weight of oil must‘ be increased up to about two U! form a wet slurry, heating the slurry of oil and
or two-and-one-‘half times the amount given in
catalyst to a cracking temperature and passing
the'above table. After continued regenerations,
it through a reaction zone to form lower boiling
the activity of the catalyst falls off and larger
hydrocarbons as vapors and sep-arating'the va
amounts of. catalyst will be required to obtain
pors from relatively dry catalyst particles.
the best results. The quantity of catalyst used 10
5. A method of converting higher‘bfoiling hy
will depend on the activity of the catalyst and the
drocarbons to lower boiling hydrocarbons which
type of catalyst used or selected.
‘
comprises mixing a gas oil with solid, powdered,
The cycle gas oil separated from the reaction
adsorptive, cracking catalyst in a mixing zone
products in the above examples was a better
to form a wet slurry, heating said slurry of oil
cracking stock than cycle gas oil obtained with
and catalyst to a temperature su?icient to sub
stationary bed catalyst operations, and also a
stantially completely vaporize said gas oil, pass
larger yield of gas oil was obtained with our
ing the mixture or vaporized gas oil and catalyst
invention.
particles through a reaction zone wherein higher
While we have set forth examples of operating
boiling hydrocarbons are converted to lower'boil
and treating oil slurries containing catalyst, it is 20 ing hydrocarbons in vapor form, separating the
to be understood that'these examples are by Way
product vapors from the catalyst particles with
of illustration only, and modi?cations and ‘ out substantially cooling the reaction products ‘so
changes may be made within the scope of the
as to obtain a dry separation and subjecting ‘the
disclosure without departing from the spirit of
separated-catalyst particles to contact with a
the invention.
heated gas to vaporize residual oil upon said cat’
active.
If a less active catalyst or a less active
We claim:
1. A method or converting higher boiling hydro
carbons to lower boiling hydrocarbons which com~
prises mixing a relatively heavy hydrocarbon oil
with about 38% by weight on the oil of powdered
Super Filtrol in a mixing zone to form a catalyst
oil slurry, heating the slurry of oil and catalyst
to an elevated temperature so that the hydro
carbon oil is substantially completely vaporized
and is maintained'at a conversion temperature ~
alyst particles.
' ‘
6. A method of converting higher boiling hy
drocarbons to lower boiling hydrocarbons which
comprises mixing a gas oil with solid, powdered,
adsorptive, cracking‘ catalyst in a mixing zone
to form a Wet slurry, heating said slurry of oil
and catalyst to a temperature sufficient to ‘sub
stantially completely vaporize said gas oil, pass
ing the mixture of vaporized gas oil and catalyst
particles through a reaction zone wherein higher
boiling hydrocarbons are converted to lower boil
in the presence of the Super Filtrol particles, sep
arating vapors from catalyst particles Without
, ing hydrocarbons in vapor form, separating the
substantially cooling the reaction products so as
product vapors from the catalyst particles with»
to obtain a substantially dry separation, contact
out substantially cooling the reaction products
ing the catalyst particles with a heated gas to 40 so as to obtain a dry Separation, subjecting the
remove residual oil from the catalyst particles,
separated catalyst particles‘ to contact with a
and fractionating the vapors to separate con
heated gas to vaporize residual oil upon said cat
densate oil from relatively light hydrocarbons
alyst particles, combining the vaporized residual
within the gasoline boiling range.
_ oil'with the product vapors and fractionating the
2. A method of converting higher boiling hydro
'" combined vapors to obtain a fraction boiling
carbons to lower boiling hydrocarbons which com
within the gasoline boiling range.
prises mixing a relatively heavy hydrocarbon oil
'IJA method of convertinghigher boiling hy
with about 38% by weight on the oil of powdered
drocarbons to lower boiling hydrocarbons which
Super Filtrol in a mixing zone to form a catalyst
comprises mixing a gas oil with solid, powdered,
oil slurry, heating the slurry of oil and catalyst
adsorptive, cracking catalyst‘ in a mixing zone to
to an elevated temperature so that the hydrocar
vform a wet slurry, heating said slurry of oil and
bon oil is substantially completely vaporized and
catalyst to a temperature sufficient to substan
is maintained at a conversion temperature in the
tially completely vaporize said gas oil, passing the
presence of the Super Filtr'ol particles, separating .
mixture of vaporized gas oil and catalyst par
vapors from catalyst particles without substan
ticles through a reaction zone wherein higher
tially cooling the reaction products so as to obtain
boiling hydrocarbons are converted to lower boil
a substantially dry separation and fractionating
ing hydrocarbons in vapor form, separating the
the vapors to separate condensate oil from rela
product vapors from the catalyst particles with
tively light hydrocarbons within the gasoline boil
out substantially cooling the reaction products
ing range.
so as to obtain a dry separation, subjecting the
3. A method of converting higher boiling hy
separated catalyst particles to contact with a
drocarbons to lower boiling hydrocarbons which
‘heated gas to vaporize residual oil upon said cat
comprises mixing a relatively heavy hydrocar
alyst particles, combining the ‘vaporized residual
bon oil with about 35 to about 100% by weight on
oil with the product vapors and fractionating
the oil of a powdered, adsorptive, cracking cat
the combined vapors to separate condensate oil
alyst in a mixing zone to form a catalyst-oil
slurry, heating the slurry of oil and catalyst to
an elevated temperature so that the hydrocarbon
oil isv substantially completely vaporized and is
maintained at a conversion temperature in the 70
presence of the particles, and separating vapors
from catalyst particles without substantially cool
ing the reaction products so as to obtain a dry
separation.
4. A method of cracking higher boiling hydro
from‘ the relatively light hydrocarbon fraction
boiling within the gasoline boiling range and re
cycling the condensate oil to said mixing zone for
further treatment.
8. A method of converting higher boiling hy
drocarbons to lower boiling hydrocarbons which
comprises mixing a gas oil with about 35 to about
100% by Weight based on the oil of a solid; pow
dered, adsorptive, cracking catalyst in a mixing
zone to form a wet slurry, percentages of cat
2,405,959
7
8
alyst in‘the lower portion ofthe range being used
‘when the catalyst is active and'percentages in
the upper portion of the range being used when
the catalyst is less active, heating said slurry of
higher boiling ‘hydrocarbons are converted to
lower boiling hydrocarbons in vapor form, sep
arating the product vapors from the catalyst
particles without substantially cooling the reac
oil and catalyst to a temperature sunicient to
tion products so as to obtain a dry separation,
subjecting the separated catalyst particles to con
tact with a heated gas to vaporize residual oil
‘passing the mixture of vaporized gas oil and cat
"upon said catalyst particles, combining the va
alyst particles through a reaction Zone wherein
porized residual oil with the product vapors and
higher boiling hydrocarbons are converted to
lower boiling hydrocarbons in?vapor form and 10 fractionating the combined vapors to separate
condensate oil from the relatively light hydro
separating the product vapors from the catalyst
carbon iraction boiling within the gasoline boil
particles without substantially cooling the reac
ing range and recycling the condensate oil to said
tion products so as to obtain a dry separation.
mixing zone for further treatment.
9. A method of converting higher boiling hy
12. A method of converting higher boiling hy
drocarbons to lower boiling hydrocarbons which 15
drocarbons to lower boiling hydrocarbons which
comprises mixing a gas oil-with about 35 to about
comprises mixing a gas oil with about 35 to about
100% by weight based on the‘ oil of a solid pow
100% by weight based on the oil of an active
dered, adsorptive, cracking catalyst in a mixing
clay cracking catalyst in a, mixing zone to form
zone to form a wet slurry, percentages of cat
alyst in the lower portion of the range being used 20 a wet slurry, heating said slurry of oil and cat
alyst to a temperature sufficient to substantially
when the catalyst is active and percentages in
completely vaporize said gas oil, passing the mix
the upper portion of the range being used when
ture of vaporized gas oil and catalyst particles
the catalyst is less active, heating said slurry of
through a reaction zone wherein higher boiling
oil and catalyst to a temperature su?icient to
substantially completely vaporize said gas oil, 25 hydrocarbons are converted to lower boiling hy
drocarbons in vapor form and separating the
passing the mixture of vaporized gas oil and cat
product vapors from the catalyst particles‘ With
alyst particles through a reaction zone wherein
out substantially cooling the reaction products
higher boiling hydrocarbons are converted to
so as to obtain a dry separation.
lower boiling hydrocarbons in vapor form, sep
13. A method of converting higher boiling hy
arating the product vapors from the catalyst par 30
drocarbons to lower boiling hydrocarbons which
ticles without substantially cooling the reaction
comprises mixing a gas oil with about 35 to about
products ‘so as to obtain a dry separation and
100% by weight based on the oil of an active
subjecting the separated catalyst particles to con
clay cracking catalyst in a mixing zone to form
tact with a heated gas to ‘vaporize residual oil
upon said catalyst particles.
35 a, wet slurry, heating said slurry of oil and cat
alyst to a temperature sufficient to substantially
10. A method of converting higher boiling hy
completely vaporize said gas oil, passing the mix
drocarbons to lower boiling hydrocarbons which
ture of vaporized gas oil and catalyst particles
comprises mixing a gas oil with about 35 to
through a reaction zone wherein higher boiling
about 100% by weight based on the oil of a solid
powdered, adsorptive, cracking catalyst in a mix 40 hydrocarbons are converted to lower boiling hy
drocarbons in vapor form, separating the prod
ing zone to form a wet slurry, percentages of
uct vapors from the catalyst particles without
catalyst in the lower portion of the range being
substantially cooling the reaction products so as
used when the catalyst is active and percentages
to obtain a dry separation and subjecting the
in the upper portion of the range being used When
separated catalyst particles to contact with a
the catalyst is less active, heating said slurry of
heated gas to vaporize residual oil upon said cat
oil and catalyst to a temperature su?‘icient to
alyst particles.
substantially completely vaporize said gas oil,
14. A method of converting higher boiling hy
passing the mixture of vaporized gas oil and cat
drocarbons to lower boiling hydrocarbons which
alyst particles through a reaction zone wherein
comprises mixing a gas oil with about 35 to about
higher boiling hydrocarbons are converted to
100% by weight based on the oil of an active clay
lower boiling hydrocarbons in vapor form, sep
cracking catalyst in a mixing zone to form a wet
arating the product vapors from the catalyst
slurry, heating said slurry of oil and catalyst to
particles without substantially cooling the reac
substantially completely vaporize said gas oil,
tion products so as to obtain a dry separation,
subjecting the separated catalyst particles to
a temperature su?icient to substantially com
“ pletely vaporize said gas oil, passing the mixture
contact with a heated gas to vaporize residual
of vaporized gas oil and catalyst particles through
oil upon said catalyst particles, combining the
vaporized residual oil with the product vapors
and fractionating the combined vapors to obtain
a, fraction boiling within the gasoline boiling 00
a reaction zone wherein higher boiling hydrocar
bons are converted to lower boiling hydrocar
bons in vapor form, separating the product va
pors from the catalyst particles Without substan
tially cooling the reaction products so as to ob
range.
11. A method of converting higher boiling hy
drocarbons to lower boiling hydrocarbons which
tain a dry separation, subjecting the separated
catalyst particles to contact with a heated gas to
vaporize residual oil upon said catalyst particles,
comprises mixing a gas oil with about 35 to
about 100% by weight based on the oil of a solid 65 combining the vaporized residual oil with the
product vapors and fractionating the combined
powdered, adsorptive, cracking catalyst in a mix
vapors to obtain a fraction boiling within the gas
ing zone to form a wet slurry, percentages of
oline boiling range.
catalyst in the lower portion of the range being
15. A method of converting higher boiling hy
used when the catalyst is active and percentages
in the upper portion of the range being used when 70 drocarbons to lower boiling hydrocarbons which
comprises mixing a gas oil with about 35 to about
the catalyst is less active, heating said slurry of
100% by weight based on the oil of an active
oil and catalyst to a temperature su?‘icient to
clay cracking catalyst in a mixing zone to form
substantially completely vaporize said gas oil,
a wet slurry, heating said slurry of oil and cata
passing the mixture of vaporized gas oil and cat
alyst particles through a reaction zone wherein 75 lyst to a temperature su?icient to substantially
2,405,959
9
10
completely vaporize said gas oil, passing the mix
ture of vaporized gas oil and catalyst particles
particles, combining the vaporized residual oil
with the product vapors and fractionating the
through a reaction zone wherein higher boiling
hydrocarbons are converted ‘to lower boiling hy
the relatively light hydrocarbon fraction boiling
combined vapors to separate condensate oil from
drocarbons in vapor form, separating the prod
within the gasoline boiling range and recycling
uct vapors from the catalyst particles without
the condensate oil to said mixing zone for further
substantially cooling the reaction products so as
treatment.
to obtain a dry separation, subjecting the sep
PAUL E. KUHL.
arated catalyst particles to contact with a, heated
ROBERT M. SHEPARDSON.
gas to vaporize residual oil upon said catalyst 10
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