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Патент USA US2406778

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Sept. 3, 1946.A
Filed Deo. _15, 1941
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Patented Sept. 3, 1946
Willard E. Kruse, Chicago, Ill., Cecil W. Nyse
wander, `Highland, Ind., and John A. Bolt, Chi
cago, Ill., assignors to Standard Oil Company,
Chicago, Ill., a corporation of Indiana
Application December 15, 1941, Serial No. 422,981
2 Claims, (Cl. Zim-683.5)
This invention relates to improvements in alu
feed stock such as light naphtha is previously
minum chloride hydrocarbon conversion proc
esses and it pertains more particularly to improved
methods and means for introducing make-up
aluminum chloride into a continuous conversion
In certain continuous aluminum chloride hy
drocarbon conversion processes such as cracking,
pended form for an extended period of time.
Slurries of make-up aluminum chloride which
are formed by the use of such pretreated naphtha
can be readily handled and injected into the sys
polymerization, alkylation, isomerization, etc.,
it is essential to effect a continuous or intermit
treated with aluminum chloride before it is em
ployed for making up the aluminum chloride
slurry, the resulting slurry will remain in sus
Even in the case of a pretreated slurrying
10 vehicle, however, it is desirable to avoid a pro
longed time between slurry formation and actual
slurry injection.
in order to maintain catalyst> activity at the dem
We have discovered that a remarkably and un
sired level. An object of our invention is to pro~
usually stable aluminum chloride slurry results
vide an improved method and means for supply
ing make-up aluminum chloride to such a con 15 from the use as slurrying agents of liquids which
have already undergone treatment in the isom
tinuous reaction chamber. A further object i5 to
erization reaction itself. Products directly from
provide a new and improved aluminum chloride
the reactor (or from the settlers following the
isomerization system wherein liquids produced in
tent introduction of make-up aluminum chloride
reactor) are usually contaminated with complex
20 material that would be deleterious in the slurry
make-up aluminum chloride.
ing step; products from these points also contain
Considerable trouble has been experienced with
dissolved hydrogen chloride which promotes
the maintenance of aluminum chloride slurries
in hydrocarbon charging stocks such, for eX
comp‘ex formation and which is hence objection
ample, as light naphtha. Thus in a system for
able in the slurrying step. However, the cooled
injecting aluminum chloride into a light naphtha 25 product from which hydrogen chlorideY has been
the system may serve as a vehicle for introducing
isomerization reactor Where a slurry of 2 pounds
of finely ground aluminum chloride per gal
lon of 153° F. end point naphtha feed stock is v
removed is an excellent source of slurrying liquid.
Also, the heavy ends of the isomerization prod
ucts, i. e., components boiling just above neo
employed, at least ’75% of the aluminum chloride
heXane, are also effective for producing a stable
settles out of the naphtha at a rate of 20 to 30 30 slurry which is substantially free from sticky and
feet per minute. Furthermore, on contacting the
adhesive materials; the recycling of this heavy
fresh feed the aluminum chloride almost imme
isomate fraction serves the additional and imdiately becomes sticky and tends to form a paste.
portant function of increasing the- neohexane
It appears that the naphtha contains a small
production in the isomerization system.
amount of material which reacts readily with the 35
aluminum chloride to form an adhesive.
It might be supposed that since products from
the isomerization system are effective slurrying
thorough drying of the charging stock does not
agents that light iso~parañins would likewise be
avoid the tendency of the catalyst to agglom~
effective. A test with isooctane as a slurrying
erate and become sticky, and it, therefore, ap
agent showed that this agent was even worse
pears that the trouble is caused by the nature 40 than untreated light naphtha charging stock.
of the charging stock itself or by a trace of ad»
The use of isooctane resulted in an adhesive mass
hesive-forming materials in said charging stock.
that settled and stuck to the bottom of a con
An object of our invention is to avoid the forma
tainer. Isooctane is thus utterly worthless as a
tion of sticky or adhesivesubstances in suchcat
slurrying agent.
alyst slurries and to avoid the clogging of line-s,
The »sludge produced in the aluminum chloride
pumps, valves, injection means, etc., through
step (or spent sludge from the isom
which the slurry must be passed en -route to the
erization reaction Zone) may be introduced into
reaction chamber.
av high pressure hydrogen chloride generator and
A further object of our invention is to vprovide
a more efñcient utilization of liquids separated 50 treated ywith a hydrolyzing agent such as sulfuric
acid or water in order to supply at least a part
from isomerization products in an isomerization
of the necessary make-up hydrogen chloride
reaction system. Other objects will become ap-4
which is required in the isomerization reaction.
parent as the .detailed description of ourinven
Alternatively it may be used as catalyst mate
tion proceeds.V
We have discovered that if the hydrocarbon 55 rial in the isomerization reactor, being intro
duced separately or with recycled complex and
not with the make-up catalyst slurry.
Our invention will be more clearly understood
from the following detailed description read in
which is a schematic flow diagram of an improved
about 35 pounds pressure. Hydrocarbon gases
may be purged from the system through line 45
and the butane from the base of the separator'
may be returned through line 45, pump 4i) and
line 4I back to the top of the absorber. Hydrogen
leaves the top of the absorber through line 4l.
The charging stock-hydrogen chloride solution
system for isomerizing light naphtha.
from the base of absorber 20 is forced by pump
conjunction with the accompanying drawing
which forms a part of this specification and
While our invention is applicable to a wide
48 4through heater 49 and lines 55 and 50a into
variety of aluminum chloride-hydrogen chloride li) isomerization reactor 5I. Hydrogen from line 4l
hydrocarbon conversion processes, it is particu
larly applicable in the process for isomerizing a
or from outside source 52 is introduced by com
pressor 53 either into line 50 or directly into re
light naphtha consisting essentially of parañinic
actor 5I. Make-up aluminum chloride ín the
hydrocarbons of the butane to hexane boiling
form of a slurry is introduced into reactor 5I from
range. Referring to the drawing, a virgin naph
a slurry tank by means of pump 54 and line 55.
tha charging lstock is introduced by pump iil
Aluminum chloride or complex from other parts
through heat exchanger II to fractionating
of the system are introduced into the reactor
tower I2 which is provided with suitable heat
through line 56.
ing means I3 at its base and which is operated
The reactor contains a large amount of alumi
under such conditions that heptanes and heav 20 num chloride catalyst material which is usually
ier hydrocarbons are removed from the base
in the form of an aluminum chloride hydrocarbon
through line I4. An intermediate cut consisting
complex. The charging stock passes upwardly
essentially of C5, Ce or C5 and Cs hydrocarbons
through this catalyst material in ñnely divided
may be withdrawn by pump I5 (a plurality of
d‘spersed phase at a space velocity of about .2
towers will be used for the fractionation in ac 25 to 4 volumes of liquid charging stock per hour
tual practice, the side stream being a diagram
per Volume of catalyst material. The tempera
matic representation) through heater I5 and
ture in the reactor is within the range of 100 to
then split into two streams, the 'small stream
400° F. and is usually in the general viciniïy of
passing by line I'I to pretreating tank I3 and the
250° F. The pressure in the reactor is in the
large Istream pas-sing by line I 9 to hydrogen chlo 30 range of 500 to 1500 pounds per square inch and
ride absorber 2B. When the make-up aluminum
may be about 850 pounds per square inch. Reac
chloride is slurried with recycled material. the
tion products are withdrawn from the top of re
valve in line I 'I may be closed and all of the
actor 5I through lines 57 and 58 to warm settler
59 and thence through line EU, cooler 6I and pres
sure reducing Valve 62 to cool settler 63. Gases
through line 2l and cooler 22 to reflux drum 23
leave the top of the cool settler through line 64.
from which' uncondensed gases may be vented
and are returned by line 32 to hydrogen chloride
through line 24. When an intermediate cut has
absorber 20.
been withdrawn, the reflux condensate may con
Clear product liquids leave the cool settler
sist essentially of butane (or a mixture of bu 40 through line 65 and are introduced by pump 56
tanes and pentanes) which is withdrawn from
into hydrogen chloride Stripper column 61 which
the base of the drum by means of pump 25. A
is provided with a suitable heating means 68 at
portion of this reflux condensate may be re
its base. The overhead from this stripper may be
turned through line 26 to serve as reflux in the
passed through line 69 to line -32 for recyclingV or
top of tower I 2. Reñux condensate from this 45 may be passed through cooler ‘I0 to reñux drum
source may also be introduced through line 2l
'I I. Gases from the top of this drum pass by linesy
to line I7, through line 23 to line I9, through line
12 and line 32 to the hydrogen chloride absorber
29 to a hydrogen absorber system, or through
20 and liquids from the base of this drum may
line 30 to storage or to a point of use elsewhere
be either returned by line 'I3 for use as reflux in
in the refinery.
the top of the stripper or may be withdrawn
The hydrogen chloride absorber 2i! is prefer
line 14. The product from line 74 is
ably operated under a superatmospheric pressure
chieily isobutane and when it is passed to an
which may range from about 50 to 350 cr more
aluminum chloride alkvlation system it is un
pounds per square inch but which is preferably in
necessary that dissolved hydrogen chloride be re
the general vicinity of 200 to 250 pounds rer
charging stock may be passed to the absorber.
Overhead from fractionator I2 is withdraw):` ‘-‘~
square inch. Make-up hydrogen chloride may b2
introduced through lines 3| or 33 and a gaseous
stream containing hydrogen chloride is introduced
at the base of this absorber through line 32. Un
55 moved therefrom.
Stripper tower S'I may thus
function both as a hydrogen chloride stripper and
as a stabilizer tower.
Liquid products from the base of tower El are
passed directly by line 'I5 or through cooler 'I6
absorbed gases, chiefly hydrogen, methane, eth 60 to caustic scrubber and Wash tower TI. Caus
ane, etc., leave the top of the absorber through
line 34 and may be vented from the system
through line 35 or introduced through line 36 to
gether with additional hydrogen containing gases
from line 31 into the base of absorber 33, a suit
able compressor 39 being employed for this purpose. Butane from line 29 may be introduced by
pump 49 and line 4I to the top of absorber 38.
This absorber may be provided with suitab`e
baffles or bubble plates and it may be operated at
a temperature of about 100° F. and a pressure of
about 900 pounds per square inch. Gaseous hy
drocarbons are absorbed and introduced through
line 42 and pressure reducing valve 43 into sep
arating chamber 44 which may Operate under
tic may be introduced through line 78 and water
through line 79. The wash water may be
trapped out above the caustic inlet or the water
and caustic may both be removed from the base
65 of the tower through line 80.
The neutralized and water washed product is
withdrawn from the top of the wash tower
through line BI and it may either be withdrawn
Vfrom the system through line 82 or passed
70 through line 83 and heat exchanger 84 to stabi
lizer or fractionating tower 85 which is provided
with a suitable heating means 86 at its base.k
Heavy isomate or hydrocarbon material may be
withdrawn from thebase of the stabilizer through
line 81 and removed from the system through
line 88. `or returned lthrough. vlinesßß and 30, tothe
slurry tank. A light isomateßmay be, withdrawn
as. a side stream from tower 8.5 through line 9|..
(Here again, a’plurality .of ,towers` would be used
in >actual practice.)
or >5Ib through lines 5,6 or IDB.
>The lpretreating with aluminum chloride in
lump form,> supported form or complex form in
chamber I8 alters thewcharaoter of the charging
stock in such a Way as to prevent the formation
`Overhead :from the stabilizer is passed `through
cooler 92toreflux drum’Bßfrom which gases
recovery drum I05„or >to one of .the reactors 5I
of sticky adhesive compounds with the powdered
aluminum chloride in slurry tank IIB. In the
absence .of ,the nretreating _step the. slurry 'formed
he vented through line. 8.4... >A portion .ofthe vre
flux may be returned'hyypump .95 Athrough line
96Á to theztop of the .stabilizer and a, lightfrac
tion consisting,V iorexar'npl , :chiefly .of butanes
maybe .withdrawn from .thefsystem through line
.in tank ,|.|8 rapidly plugs lines 55, 55a, etc. and
the pumps, -valves, etc. >associated therewith.
The pretreating step insures'the formation of a
slurry »which-is. sufiiciently free from sticky .and
adhesive materials so that it will not agglomerato
Instead of ¿employing a .single'reactor we may
employ Ía multiple reactorV system. Thus .charg
ing stockv with ahsorbedhydrogen chloride :may
be introduced throughlineâßb to reactor Elib and
make-up .catalyst `may be .added to .this reactor
through :line 5517. Alternatively, the products
leaving the top of reactor'äl may be> passed by
line .98..tl1rough cooler 99 .and to reactor 5Ib> and
the products from the top'of reactor 5|b Amay be
passed through “line |00 and line v58 to warmset
and will not cause aplugging of the transfer limes,
pumps and valves.
A hydrolyzing agent such as sulfuric >.acid or
wateris `introduced¿into drum |05 through line
|25 and the sludge or `colsey residue is withdrawn
from the .drum .through line |26. Recovered hy
Y drogen chloride _is returned through ,line |21 and
line >32 to absorber Z0. If water is used as a hy
drolyzing ragent it should be employed in lless than
stoichiometric amounts in order that the recov
tler 59.
¿Catalyst from the Vbase of reactor `5|b may lbe 25 ered hydrogen chloride ¿may be substantially an~
hydrous. Larger amounts of recovered khydrogen
withdrawn by pump |.0I and either withdrawn
chloride may be obtained by the use of sulfuric
from the system through .line |02, passed by lines
acid and such use is particularly advisable where
|03 and 5B .to reactor 5I or passed. through, lines
|03 to line |04 to "hydrogen Vchloride recovery
sludge cokermeans `are available Vfor recovering
drum |65. Catalyst‘'withdrawn from the 30
base of reactor. 5| by pump |05 and either with_
drawn from the system through line |01, passed
to reactor EIb .through line `I08'or passed to the
hydrogen chloride recovery drum through lines
|09 and |114.L `Material from lines ,|02 or |01 or. 35
both may be .employed to pretreat naphtha in
the sulfuric acid.
tank I8.
settieu catalyst _material from settler 59 may
be passed through lines .III and |08 to reactor
The hydrogen chloride _recovered from chamber
|05 mayA notbe _suiiicient to supply all of the re
quired >make-up `hydrogen chloride andV addi
tional hydrogen chloride may, therefore, have to
be added through line .3L „ The additional `hy
drogen chloride may be generated in a high
pressure generator |21 luy-adding a hydrogen sup
plying agent through line |28 and a chlorine` sup
plying agent through line |29. The by-oroduct
40 vfrom .this generator mayy be >withdrawn through
line |30 and the produced hydrogen chloride may
actor 5|. Precipitated catalyst material from
be introduced directly through line 33 into the
cool settler B3 may be pumped as a slurry by
base of the absorber 20 without the necessity of
pump ||3 through lines ||4 and 90 to the slurry
employing pumps or purifying means. The hy
tank but is preferably pumped through lines I I5
and |08 to reactor 5|b or through lines III;` and 45 drogen supplying agent may be hydrogen itself,
a gas containing hydrogen (e. g., from line 35),
56 to reactor 5|.
a hydrocarbon or sulfuric acid.` The chlorine
chamber 5|b or through lines || 2 and 56 to re
Our invention is primarily connected with the
supplying of make-up aluminum chloride to the
supplying agent may be chlorine gas, sodium
chloride, hydrochloric acid, etc. Thus chlorine
may be introduced through line |29 and burned
Powdered aluminum chloride from source ||1 is 50
with an excess of hydrogen or hydrogen contain
introduced into slurry tank ||8 by means of any
gas introduced through line |28 or reacted
suitable hopper, screw feeder, or other feeding
with a hydrocarbon introduced through line |28.
means. Slurry tank ||8 may be provided with a
Sodium chloride or aqueous hydrochloric acid
suitable mixer or high speed stirrer driven by
motor I 20. The oil for making up the slurry may 55 may be introduced through line |29 and sulfuric
acid may be introduced through line |28.
be obtained from pretreating tank I8 through line
While the pretreating of a portion of the feed
|2| or from various parts of the system through
stock with aluminum chloride makes it possible
line 90.
to produce a pumpable slurry in tank ||8 we
In prereating tank I8 the aluminum chloride is
preferably in lump form or is deposited on a 60 have found that a superior type of slurry is pro
duced by employing liquids recycled from the
suitable support such as Kieselguhr or is in the
system through line 8.0. Such liquid may be
form of a hydrocarbon complex. Thus lump alu
withdrawn from the product stream between
minum chloride may be introduced from source
cooler 'I6 and wash tower '|'| and passed to tank
|22 and may be retained in the pretreating cham
ber by screen support |23. Light naphtha from 65 |20 through lines |3I, 89 and 90. 'I'he product
at this point is substantially anhydrous and is
line |'| enters pretreating chamber IIB below
free from catalyst material and hydrogen chlo
screen |23 and passes upwardly through the bed
ride. The "pretreatment” of the charging stock
of lump aluminum chloride, leaving the top of
for the preparation of a slurry Vehicle is in this
the pretreating chamber through line I2 I. A vis
cous brownish red complex may be formed by the 70 instance effected in the isomerization reactor it
contacting of charging stock in this pretreating
Another liquid Which produces a highly desir
chamber and since this oil complex is heavier
type of slurry is that obtained from the base
than charging stock it settles to the base of the
of stabilizer or fractionator column B5 from lines
pretreating chamber and may be withdrawn
therefrom through line |24 to hydrogen chloride 75 81 and 89. This liquid may consist' chieñy of
methyl pentanes and unisomerized normal hex;`
ane. By using this liquid as a slurrying agent
for make-up aluminum chloride we not only ob
tain a highly satisfactory slurry but We 'also ob
unabsorbed gases from the top of the absorption
zone, making up an aluminum chloride slurry of
iinely divided «solid aluminum chloride particles
in a portion of the stream after hydrogen chlo
ride has been stripped therefrom and introducing
tain increased yields of neohexane, i. e.; We ob
tain isomerization products of higher octane
said aluminum chloride slurryV into said isom
number and hence of greater value as aviation
fuel blending stocks.
While We have described specific examples of
our invention in considerable detail it should be ll()
understood thatour invention is not limited to
these particular examples nor to the speciñc con
material contained therein.
2. The method of >isomerizing a parañinic hy
drocarbon charging stock boiling Within the bu
tane to hexane boiling range Which method com
ditions'recited therein since other examples and
other operating conditions will be apparent to
those skilled in the art from the above detailed
erization zone for maintaining the activity of the
liquid aluminum chloride-hydrocarbon complex
prises adding hydrogen chloride to said charging
stock, and introducing the charging stock With
added hydrogen chloride at a low level into a con
tinuous . isomerization zone containing a large
` `We claim:
amount of liquid aluminum chloride-hydrocar
bon complex catalyst material, eñecting isomeri
l. The method of isomerizing a paraiiìnic hy
drocarbon charging stock boiling within the bu
tane to hexane boiling range which method com
prises absorbing hydrogen chloride in said charg
zation of said charging stock in said isomeriza
tion zone, withdrawing a product stream contain-ing catalyst material and hydrogen chloride from
the upper part of said isomerization zone to a set
tling Zone, removing catalyst material from said
stream in said settling zone, introducing said
ing stock in an absorption zone to form a hy
drogen chloride solution, heating said solution toY
isomerization temperature and introducing the
heated solution at a low level in a continuous 25 stream from said settling zone to a stripping zone,
isomerization zone containing a large amount of
stripping hydrogen chloride from said stream in
said stripping zone, treating the stripped stream
with caustic to effect neutralization thereof, frac
liquid aluminum chloride-hydrocarbon complex
catalyst material, effecting isomerization of said
charging stock in said isomerization Zone, With
drawing an isomerization product stream con
taining dissolved catalyst material and hydrogen
tionating the neutralized product stream to obtain
- a plurality of fractions including a'heavy frac
tion, making up an aluminum chloride slurry of
finely divided aluminum chloride particles in a
portion of said heavy fraction and introducing
said aluminum chloride slurry into said continu
chloride from the top of the isomerization zone
to a settling zone, removing catalyst material
from said stream in said settling zone, intro
ducing the stream Whichstill contains hydrogen
chloride from said settling zone to a stripping
Zone, stripping hydrogen chloride from said
«stream in said stripping zone', returning hydrogen
chloride containing gases from the top of the
stripping zone tothe absorption zone, venting
` ous isomerization zone for Amaintaining the activ
ity of the liquid aluminum chloride-hydrocarbon
complex catalyst material contained therein.>
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