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Патент USA US2406633

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2,406,633,
Patented Aug. 27, 1946
UNITED STATES PATENT > OFFICE»
ISOMERIZATION OF SATURATED
HYDROCARBONS
‘Herman Pines and Richard C. Wackher, River-iv
‘ Side, _ 111., assignors t 0 Universal Oil Products
Company, Chicago, 111., a corporation ‘of Del
aware
No Drawing. Application November ,19, .1943,‘ ‘
Serial No. 510,912
‘
12 Claims. (Cl. 260-6835)
.
‘1
This .invention relates to the catalytic isomer
ization of isomerizable saturated hydrocarbons
drogen.
.
ing “said ‘hydrocarbon with :an .isomerizing cata
lyst under isomerization conditions in the pres-'
ence of‘al'rel‘ativelyiminor amount of a diaryl, al
kylaryl, ‘or cycloalkylaryl ether;
‘The isomerization of saturatedhydrocarbons
‘ ent time, particularly the isomerization of .nor
~
isomerizing a saturated ‘hydrocarbon by'contact
-
has assumed considerable importance at the pres
»
‘Broadly, l the '- invention comprises a ' process for
and is morespeci?cally concerned with an im
proved process wherein these hydrocarbons ‘are
isomerized under carefully selected conditions of
operation in the presence of certain aromatic
ethers;
2
di'iliculties ‘which are inherent in‘ the ‘use ~oi 'hy
“In-one specific embodiment'the present inven
10 tion comprisesa process ‘for ‘the production of
isopentane by contacting normal pentane con
taining a relatively'minor amount of a diaryl,
alkylaryl, or cycloalkylarylether with an alumi
num chloride-hydrogen chloride catalyst under
mally liquid paraffinic hydrocarbons such as pen
tane, 'hexanes. heptanes, etc., which upon-‘isom
erization gproduce compounds which. have very
desirable antiknock properties ‘when included : in
aviation gasoline blends :and other motor .fuels. 15
isomerizing
conditions.
'
'
’
'
'
»
‘We have discovered that‘the addition of these
aromatic ethers selectively suppresses the decom
Moreover, these'tisomerized products, "especially
the isomers having‘atlleastone tertiary carbon
position reactions and-permits the isomerization
atom ‘per molecule, may bealk-ylated with an fal_
of 1the saturated "hydrocarbons with ‘a high de
gree of ef?ciency and low :catalyst ‘consumption.
The exact mechanism by which these‘ aromatic
kylating agent such as \antole?n, alcohol, etc., to
produce higher molecular ‘weight alkyl‘derivatives
whichhaveivery;desirable 'antiknock qualities and
which are useful intermediates ‘in organic syn
ethers suppressdecomposition reactions‘ is not
thoroughlyunderstood, but‘ it willbe evident from
thesis-
the experimental ‘data-hereinafterpresented that »
I
.It is welliknown that saturate'dihydrocarbons
may be isomerized using catalysts of the‘Friedel
Crafts :type'such as aluminum halides, zinc hal
ides, zirconium "halides, or mixturesithereof in‘the
presence of ahydrogen halide. Therpr-imary 'op
erating "dii?culty accompanying these visomer'iza
tion operationsis the tendency toward :high cata
greatly improved results are ‘obtained when the
aromatic ethers'are'present.
‘
’
The aromatic ‘ethers whichinay beemployed
to suppress decomposition reactions during the
isomerization'of saturatedthydrocarbons comprise
30 broadly ‘ the ethers ' ‘having the "following "formula:
lyst ‘consumption ‘due ‘to the‘formation 'of’metal
halide-hydrocarbon complexes.
The catalyst
where-‘Risen aryl group and R'is analkyl, cy- -
complexes or sludges are formed by the'interac
tion of the metal halide with the products of ,
decomposition reactions which occur simultane
ously with the’ isomerization. reaction.
j, Various methods bave‘been proposed to prevent
the decomposition of the saturated hydrocarbons
thereby preventing high catalyst consu'mptions.
Forexample, it has been proposed-to'introduc'e
.cloalkyl, oriaryl. group. It will thus be seen that
the aromatic ethers which are within the scope
of our. invention'fall into three groups, namely,
the diaryl ethers, the alkylaryl ethers, ‘and the cy
cloalkylaryl ethers. Typical diaryl ethers which
‘may be employedare diphenyl ether ‘and the al
, 40
kylated 'diphenyl ethers suchtas methyltolyl ether.
Typical examples'of the alk-ylaryl ethers which
hydrogen into "the reaction zone to suppress de_
maybe used .in our invention are methylphenyl
composition and presumably‘ to hydrogenate un
saturated hydrocarbcn fragments formed by de
‘ether .or anisole-?ethylphenyl ‘ether or phenetole,
hydrogen as a decomposition suppressor has been
are illustrative cfvthecycloalkylaryl ethers.
gpropylphenyl ether, butylphenyl ether, etc. Cy
composition of the charging stock. The use of 2:45 clop‘entylp‘henyl ether and cyclohexylphenyl ether
‘found'to beevery expensive and entails the use ‘of
_ a considerable amount of auxiliary‘ equipment
such as compressors, separators, etc., to provide .av
means for recycling the hydrogen to the reactionv
.Itis an object of the present invention to pro
vide a method. forv suppressing the-decomposition
of. theisomerizable hydrocarbons which‘ is econo
rnomical and practical and which obviates the
’ These various ‘ethers are‘not necessarily equiv
alent in their effectiveness since obviously-differ
'ent amounts '~.Of aromatic ether maybe required
dependent upon thenatureof ‘the catalyst and
chargingstock and also'upon the operatingrcon
:ditions'employed'. The concentration of theiaro
mati'c'wether in ' the isomerization charging stock
is generally?from about 1 01% 1to "about'5-‘% “by
'1 weight.‘v ‘.Theiuserof the "above mentioned aro
2,406,633
3
' 4
matic ethers to suppress decomposition reactions
vestigate the e?ect of methylphenyl ether and.
diphenyl ether in the normal pentane isomeriza
tion reaction. An electrically heated autoclave
is particularly applicable to the isomerization of
normal pentane since normal pentane exhibits an
unusual tendency to undergo decomposition when
equipped with a mechanical stirrer was charged
subjected to isomerizing conditions. The various; 5 with 85 grams of normal pentane and the desig
aromatic ethers are separated from the isomeriz
nated amount of aromatic ether, and anhydrous
ation reaction products by fractionation or other
aluminum chloride and hydrogen chloride were
suitable means and may be recycled to the isom-.
erization step.
added. The autoclave was sealed and the reac
tion was carried out for a period of six hours.
A blank run was also made without the addition
of an aromatic ether to suppress decomposition
.
The operating conditions of the isomerization
process such as temperature and pressure will
vary somewhat depending upon the aromatic
reactions.
ether and catalyst employed. Ordinarily, tem
peratures within the range of about 50° F. to
about 350° F. and more preferably within the
range of from about 120° F. to about 250° F. and 15
pressures varying from substantially atmospheric: 7. v
The pertinent data from these tests
are tabulated as follows:
Run No.
to about 500 pounds per square inch or more are _
desirable.
-
.
Charge, grams:
Aluminum chloride".
Any of vthe well-known Friedel-Crafts type
isomerization catalysts may be employed. It is
desirable that a hydrogen halide such as hydro
gen chloride and hydrogen bromide be used in
conjunction with these catalytic materials. The
ordinary concentration of the hydrogen halide
Hydrogen chl0ride_.__.
n—Pentane _________ __
Methylphenyl ether___
Diphenyl ether. _ .
Temperature, °O___
is within the range of about 1 to about 40 mol
per cent of the charge and preferably from about
5 to about 20 molper cent. The preferred cata
lysts comprise the chlorides and bromides of
aluminum, 'zinc, zirconium, and iron, either alone
or in admixture with one another. These cata
lysts may be employed in the solid granular state
or upon inert supporting materials such as alu
mina, silica, thoria, crushed ?rebrick,v quartz,
activated clays, and activated chars. I '
It is also within the scope of this invention to
employ mixtures of these compounds and in par
ticular the aluminum halides with the halides of
antimony, bismuth, and arsenic, to form catalyst
i-Butane.____
30
54.1
110.1 ____ ..
n-Butane__
__
8.1
i-Pentane_.
_ _
19.2
54.9
63.6
u-Pentane___
_.. 11.8
Hexane and higher _______________________ __
6. 8
30.3
4. 2
0.5
44.3
0.7
1. 4
LAlso includes’ 0.1% H01.
In ‘run 1, which was the blank run, it will be
noted that although 19.2% isopentane was obtained
there was also a total butane production of 62.2%
35 which - represents a relatively low efficiency of
conversion to isopentane.
In run 2 employing
methylphenyl ether, 54.9% isopentane was ob
tained with only 10.5% of butane thus indicating
composites which are molten under the conditions 40 the marked e?ect of methylphenyl ether or ani
of
operation.
‘
.
,
‘
sole in‘suppressing decomposition reactions. It
The isomerization'operation may be conducted
in various ways. For example, the heated hydro
carbon charge containing the added aromatic
ether may be passed either in the liquid, vapor,
will also be noted in run 2 that 30.3% of uncon
verted normal pentane was recovered. At some
or mixed phase through a reaction zone contain
ing a bed of solid granular catalyst either sup
obtained.
ported ‘or unsupported, and the reaction products
may be separated into the desired isomers and
unconverted material the latter being recycled to
the reaction zone. I
what more severe‘ operating conditions higher
conversions to'isopentane would undoubtedly be
'
In run 3 diphenyl ether was employed to sup
press decomposition. Comparing the results of
this test with the results obtained in run 1 it will
be noted that the presence of the aromatic ether
50 suppressed the butane production to a very
marked extent and resulted in a high yield of iso
Another method of operation consists of em
pentane.
‘
playing a catalyst supply chamber containing .a
We claim as our invention:
bed of granular catalyst through which a stream
1. An isomerization process which comprises
of the charge is passed in liquid phase to dis
solve the required amount of catalyst. This cata 55 contacting a paraffin‘ hydrocarbon under isomer
izing conditions with a‘ metal halide isomerizing
lyst-containing stream is introduced into a reac
catalyst of theFriedel-‘Crafts type in the pres
tion zone along with a regulated amount of the
ence of a relatively minor amount of an ether
hydrogen halide, and a substantial portion of
having the formula R-—O-R' wherein R is an
the hydrocarbon is isomerized therein. This re
action zone may comprise a large vessel which -60 aryl group and R’ is a, hydrocarbon radical se
will provide suf?cient time for the reaction to
occur or may be ?lled with a retaining material
such as molten salts, hydrocarbon-metal halide
complexes, or solid packing materials such as
bauxite,‘ Raschig rings, berl saddles, granular
quartz and other materials well known to those
skilled in the art.
‘ '
>
‘
The following examples illustrate in a general
way the e?ectiveness of the ‘aromatic ethers dis
closed herein in suppressing decomposition reac
tions during the isomerization operation .' ' It is not
intended that these examples unduly limit the
‘generally broad scope of this invention.
A series‘v of experiments was conducted to in
lected from the class consisting of alkyl, cyclo
alkyl, and aryl ‘groups.
' '
. 2. An isomerization processv which comprises
contacting a normally liquid paraffin hydrocar
bon and an ether having the formula RPOe-R'
wherein R is. an aryl group and R’ is a hydro
carbon radical selected from the‘class consist
' ing of alkyl, cycloalkyl, and arylv groups with a
Friedelecrafts type .isomerizling catalyst under
70 isomerizing conditions.
'
,
3. An isomerization 'process which comprises
contacting a. normally liquid para?ln hydrocar
bon and an ether having the formula lt-O-R'
wherein'R is an aryl group and R’, is a hydro
75 vcarbon radical selected from‘the class consist
2,406,633
5
a hydrocarbon radical selected from the class
ing of alkyl, cycloalkyl, and aryl groups with a
consisting of alkyl, oycloalkyl, and aryl groups
metal halide of the Friedel-Crafts type and a
with a metal halide isomerizing catalyst of the
hydrogen halide under isomerizing conditions.
Friedel-Crafts type under isomerizing conditions.
9. An isomerization process which comprises
4. An isomerization process which comprises
contacting a normally liquid para?in and an
contacting normal pentane containing a rela- ‘
tively minor amount of an ether having the for
mula R—O—-R’ wherein R is an aryl group and R’
is a hydrocarbon radical selected from the class
ether having the formula Pt-—O-R’ wherein R.
is an aryl group and R’ is a hydrocarbon radical
selected from the class consisting of alkyl, cyclo
alkyl, and aryl groups with an aluminum chloride
consisting of alkyl, cycloalkyl, and aryl groups
catalyst and hydrogen chloride under isomeriz 10 with an aluminum chloride catalyst and hydrogen
ing conditions.
chloride under isomerizing conditions.
5. The process of claim 1 wherein said ether
10. The process of claim 9 wherein said ether
comprises methylphenyl ether.
comprises methylphenyl ether.
6. The process of claim 1 wherein said ether
comprises diphenyl ether.
'7. The process of claim 1 wherein said ether
15
11. The process of claim 9 wherein said ether
comprises dip-henyl ether.
12. The process of claim 9 wherein said ether
comprises cyclohexyphenyl ether.
8. An isomerization process which comprises
HERMAN PINES.
.
contacting normal pentane containing a relatively
RICHARD
C.
WACKHER.
minor amount of an ether having the formula 20
comprises cyclohexylphenyl ether. .
R,--O--R’ wherein R is an aryl group and R,’ is
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