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Патент USA US3084214

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United States, Patent 0 ’
3,084,204
Patented Apr. 2, 1963
2
1
the name of Triple A. The incorporation of a small
3,084,204
amount of ?uorine in this catalyst, e.g., 1 to 5 weight per
PROCESS FOR ALKYLATION IN THE PRESENCE
cent, markedly and unexpectedly increases its value as
OF A SEICA-ALUMINA-FLUORINE CATALYST
an alkylation catalyst. The silica-alumina cracking cata
Lionel Domash, Wilkins Township, Allegheny County,
Stephen L. Peake, Pittsburgh, and Raymond C. (idioso, (Fl lyst can be prepared by any of the known methods for pre~
paring synthetic‘ silica-alumina compositions, including
coprecipitation and cogelation.
Glenshaw, Pa., assiguors to Gulf Research 8; Develop
ment Company, Pittsburgh, Pa., a corporation of Dela
As indicated, the catalyst contains a minor amount,
such as 1 to 5 weight percent, of ?uorine, and preferably
10 1 to 3 weight percent of ?uorine. The ?uorine can be
added by treating the silica-alumina composite with an
This invention relates to an alkylation process and
aqueous solution of hydro?uoric acid or with gaseous
more particularly to the alkylation of aromatic hydro
hydrogen ?uoride. The ?uorine-promoted catalyst can
carbons with ole?ns in the presence of a speci?c catalyst.
also be prepared by using boron tri?uoride and a silica
It is known in the prior art to alkylate aromatics such
as benzene and toluene with ole?ns such as ethylene and 15 alumina base that contains enough water to react with the
ware
No Drawing. Filed May 9, 1960, Ser. No. 27,501
2 Claims. (Cl. 260-671)
boron tri?uoride to form hydrogen ?uoride, the hydrogen
?uoride then reacting with the silica-alumina to form
‘ propylene to produce compounds that are valuable as
>' chemical intermediates or as components of high octane
?uorine on the silica-alumina catalyst.
gasoline. For example, the meta- and para-isomers of
cymene produced by alkylating toluene with propylene
have very high blending octane numbers and are valuable
gasoline components. They are also valuable as inter
mediates in the production of dibasic aromatic acids.
Various catalysts have been proposed for alkylation of
carbon or a mixture of two or more of the same, or can
be a hydrocarbon fraction having a high concentration of
mononuclear aromatics, e.g., 50 percent or higher, ‘and
aromatics with ole?ns. These include acid catalysts such
as hydrogen ?uoride and sulfuric acid, which are em
ployed in the liquid or gaseous state.
'
The aromatic charge stock for our process can be any
of the mononuclear aromatics that are susceptible to
alkylation. Preferred stocks are benzene and toluene.
The charge stock can be a single such aromatic hydro
containing other hydrocarbons, such as para?‘ins, that are
However, these
normally present in petroleum distillate fractions boiling
highly corrosive ?uid catalysts have had certain draw
backs, including the dif?culty of recovering uncontami
in therange of the particular mononuclear aromatics.
The ole?ns employed in our process are ole?ns of the
have led to the use of solid cracking catalysts of the silica~ 3O C2-C5v range. The preferred ole?n is propylene. The
nated hydrocarbon products, and recent developments
alumina type for certain alkylation reactions. We have
alkylation reaction can employ a single highly puri?ed ole
now made a valuable improvement in the alkylation of
aromatics with ole?ns in the presence of a solid catalyst
?n or a mixture of two or more ole?ns or a fraction rich
in one or more of the ole?ns and containing paraf?ns or
other hydrocarbons of similar boiling range._ ,
through the employment of a ?uorine-promoted silica
alumina catalyst.
’
35
The process of the invention in general comprises con
tacting a mononuclear aromatic hydrocarbon with a low
molecular weight ole?n in the presence of a silica-alumina,
cracking-type catalyst containing a small amount of
The catalyst employed in our process can provide im
portant advantages over other catalysts over a considerable‘
range of alkylation conditions but shows its greatest
superiority in a certain range of conditions. Broadly, the
conditions can include a temperature of 300° to 600° F.,
a pressure above 500 p.s.i.g., e.g., 500 to 1500 p.s.i.g. or
?uorine. In a preferred modi?cation of the process Where
in its greatest advantages are obtained the catalyst con
higher, a mol ratio of aromatics to ole?n in the range of
1:1 to 10:1, and a liquid-hourly space velocity of 1 to 6
tains about 25 percent alumina and 1 to 3 percent ?uorine,
volumes of hydrocarbon per volume of catalyst per'
the aromatic charge stock is toluene and the ole?n is
hour. In our process space velocity is de?ned as the
propylene. The reaction conditions include a temperature
in the range of 450° to 550° F., a pressure in the range 45 number of liquid volumes of aromatic plus ole?n (the
ole?n being considered as dissolved in ideal solution) per
of 500 to 1500 pounds per square inch gauge (herein
volume of catalyst per hour (hereinafter abbreviated as
after‘abbreviated as p.s.i.g.), and an aromatics to ole?n
vol./vol./hr.). The greatest advantages of the invention
mol ratio of less than 3:1. This modi?cation of the process
are obtained with the preferred reaction conditions which
is characterized by a high yield of monoalkylated product
and particularly of the valuable meta- and para-cymene 50 include: temperature of 450° ‘to 550° F., pressure of 900
to 1100 p.s.i.g., space velocity of 1 to 3 vol./vol./hr., and
isomers.
mol ratio of aromatics to ole?n of less than 3 :1 and pref
As indicated, the catalyst for our process consists essen
erably of about 2:1. The preferred space velocity of 1 to
tially of a silica-alumina composite which .is promoted
3'vol./vol./hr. is particularly preferred when dilute aro
with a’ minor amount, e.g., 1 to 5 weight percent of
?uorine. We have found that such silica-alumina com
55 matic and ole?n feeds are used.
posites respond unexpectedly to the addition of a minor
1
The following examples describe the alkylation of tolu
can be any of the known silica-aluminas such as are em
ene with propylene over different catalysts and demon
strate the unexpected advantages of our procedure of
alkylation of aromatics in the presence of a ?uorine-pro
ployed as cracking catalysts, but the preferred composition 60
moted, silica-alumina catalyst.
amount of ?uorine as demonstrated in marked improve
ment in alkylation results. The silica-alumina composite
consists of 20 to 30 weight percent alumina and the rest
silica. A particularly valuable catalyst of this description
is the silica-alumina catalyst containing about 25 percent
alumina marketed by American Cyanimid Company under
'
-
‘
EXAMPLE I
The catalyst was granular, unpromoted silica-alumina
of 10-20 mesh size. Speci?cally the catalyst was the so
3,084,204.
4
called “Triple A” cracking catalyst consisting of 25 weight
this connection it should be noted that the conversion
values of 36.8% and 37.3% in Example‘II correspond to
values of 73.6% and 74.6% of theoretical, because the
aromatic to ole?n ratio was 2:1 and theoretically there
fore only one-half of the toluene could react with the
percent alumina and'75 weight percent silica. The feed
consisted of a mixture of pure grade toluene and high
purity (97-99%) propylene in a ratio of 2 mols of toluene
per mol of propylene. The liquid feed was pumped up
?ow through the ?xed bed catalyst at a liquid-hourly space
velocity of 2 volumes of total hydrocarbons per volume
propylene.
A major difference between Example II and the other
of catalyst per hour. Reactor pressure was 1000 p.s.i.g.
examples is in the production of meta~ and para-cymenes
Runs were carried out at two diiferent reaction tempera
in preference to the less valuable ortho-cymene. The table
tures, 300° F. and 450° F.
10 reports yields in terms of et?ciency of production of the
particular product. In this usage the e?iciency is calcu
EXAMPLE II
lated as the mol percentage of toluene converted to the
_ :In'the runs ofithis‘examplesthecatalyst was silica-alu
particular product divided by the mol percentage of
tnina which had beenttreated‘to incorporateg3 weight per
toluene converted to all products. In run ~4~of Example
cent '?uorine infthe'catalyst. The silica-alumina was the 15 II the e?iciency for production. of meta- andppara-cymene
same as employed in‘Example‘Iand'the pretreating proce
was 39.7% and 32.6%, respectively, or ‘much higher
dure'wasasfollows: ‘121.4;grams ‘of silica-alumina was
than in the runs of the other examples. ‘In run 4 the
treated ‘at 'room'temperatureiwith 117 milliliters of an
ei?ciency for ortho-cymene was only 6.3 % , or much lower
aqueous HF solution containing '3 .27‘weight percent?uoé
than the runs of the other examples. The monoalkylate
rine. ‘.Theicatalystwas then dried and calcined at 1000° 20 distributiondata show this result even more emphatically.
Fpt‘or '10 hours: The ?nished catalyst ‘contained 2.42
They show that the ortho-isomer wasonly 7.9% of the
weight'p'ercent ?uorine. The ?xed-bed; ?uorine-promoted
monoalkylate product of run 4 whereas the lowest propor
catalyst was contacted with the‘ toluene-propylene mixture
tion of ortho- in any other. example was 26.7% .(run' 2 of
in‘the'same manner and under ‘the same conditions as
described-in Example I.
Example I).
25
- of ‘3,5-diisopropyl toluene relative to the isomers thereof.
In runs‘ 3 and 4 of 'Example'II the ei?ciencies forproduc
tion of 3,5-DIPT were 13.0% and'l0'.7%. These are
vEXAMPLE ~III
' .In ‘the runsof this example .the catalyst was silica
alumina which had been treated with boric acid to in
corporate .5 .weight percent B203 in the catalyst. The
,
Another valuable result of‘Example II is in the .yield
considerably higher than corresponding values for the
30 other runs. Although the principal airnof the process of
the inventionis production of monoalkylate,.some_poly
silicaraluminawas - the same as in Example I. and. the "pro
ccdure-was, as follows: 17.7 grams of H3BO3- was dissolved
alkylate is also produced, and it is an advantage of our
in. 1»71.milliliters.of .water at: 160". F. Thehot solution was
process-that the polyalkylate. product has a high proportion
of 3,5-diisopropyl toluene. ‘This compound is‘ valuable,
added to .l90gramsot silica-alumina. Afterthorough
mixing the catalyst was dried at250° .F. ,for 20 hours and 35 for example, as a substitute for mesitylene in various
chemical syntheses, such as oxidation to trimesic acid (1,3,
calcined at ;10Q0° vF. forl6 hours. 7 The ?xed-bed, B203
promotedsilica-alumina catalystwascontacted with the
S-benzene tricarboxylic acid).
sameitypetof alkylation feed and underthe same condi
The liquid reactor etlluent such as .described'in‘Example
H can be fractionated to produce two valuable products
tions as.in-the_ previous examples.
I
:The results obtained with .thedi?erent catalysts in the 40
havingdi?ferent utility. Thus, alight fraction having an
above examples are reported in the following table. The
datarreported-for each temperaturevare the averages of
end point of aboutl400° .F. or somewhat lowercan be
recovered which contains themonoalkylate and 'the un~
data obtainediin'two :runsatv identical reaction conditions.
converted toluene. .This fraction is a valuable gasoline
‘Table _
blending component because of its highconcentration of
45 the high octane rating .meta- and para-cymenes.
[Reaction conditions: 2'LHSV; 2:1_tol]uene:, Propylene mol ratio; 1000
'
_
_-
1
~
»
Example'No ...... -.'
Gatalyst_._..--.__'_-;
i
_
p
p.s.1.g.
I
II -
Unproruoted.v
_
--Silica-Alumina_
III
Silica-Alumina
Silica-Alumina '
with 2.42% F
wit-1175923203
Run No. ' ____ -;_._._
i
2
‘3
'
Temperature, ‘T... ~
-300
.450.
- 300
131.5
a
34
4
5
@450
300
The
heavier'fraction, i.e., the'fraction with‘ initial. boiling- point
above about 400° F., contains. the polypropylated, product.
As indicated thisrproduct of our process is rich in 3,5.-'di
isopropyl toluene which ‘is a valuable chemical inter
50 mediate. jThe diisopropyl toluene products can thus be
~ withdrawn as ultimate products of'theprocess, or if de
sired can be passed either‘to a dealkylation stage, or re
cycled, to produce additional monoalkylate.
6
From the above considerations item be seen that‘Ex
Toluene Conver-
‘
:versiomiMol per;
. oent;_-._ _________ 1.
‘
.
>36. 8
Efficiency,‘ Mol
‘
percent:
‘
,
‘
'37. 3
‘
. -..Benzene ______ __
.06
"0.6.
“ '_o,-'Cymene-_'.s-~
"m-"Cymene
\'
‘24.8'
‘114.7:
19.9'
20.4 '
‘2816
.35. 5
"21. 1*
43. 4
.0. 8
26. 7
‘27. 4
45. 9
the addition of ?uorine to the silicanlumina catalyst
0.4
markedly improves its value for’ catalyzing the alkylation
of toluene with propylene. f'I'he'?uorine-promoted cata
.
12.9
.27. 9
20.4
superior to the other examples. Theexamples ‘show that
'34. 9
'
.
230.4 ' - 34.3
1.0
‘4.5
0.9
0.5
6.3 ‘ , 27. 9 '
39.7 ' 15.0.
26.5
‘13.0
32. 6
'10.‘?
30. 4
0; 7'
T18; 8 ’
I9.8
25; 7
-19. 0
"41: 5
39.5
7. 9
50.6
,41. 5
.38. 0
20. 4
241. 6
20. 9
' 19. 7
'
33. 7
313
.
.
“b IDI-PT ==e diisopropyl toluene.
60 lyst. is superior for this purpose to the unpromoted silica
, alumina catalyst, which however is an excellent alkylation
catalyst. Furthermore, the promotion of - the alkylation
22.1
activity appears to be uniquely attributable .to ?uorine.
28. 2 65
26. 6
_
45. 3
'v'JnieachQiudieatedthenataare anaverageloitwo runs at same
conditions.
55 ample’II, in accordance with-the invention, was markedly
v
29.9
‘
'
-» 450
Y
I
“The above table shows that "Example'll employing the
?uorine-promoted, silica-alumina'catalyst was unexpected
ly superior to the other examples in every important re—
spect. Thus, in each run of Example 11 theconversion
The addition ofanother acidic promoter, namely, B503,
to'the silica-alumina did not produce the same improve
ment.
j Obviously many modi?cations and variations of the in
vention ashereinbefore set forth may‘lbe made without
departing from the spirit and scope thereof, and. therefore
70 only such limitations should be'imposed as are indicated
in the appended claims.
'We claim:
.
,
l. Theprocess which comprises contacting a'mixture
of tolueneand propylene in the liquidlphase with a silica
of‘toluene was greater than in any of the other runs. In 75 alumina catalyst containing 20 to 30 weight percent
3,084,204
5
alumina, based on the silica-alumina content, and con~
taining one to ?ve weight percent ?uorine, based on the
total catalyst, under alkylation conditions including a
temperature of 300° to 600° F., a pressure of at least
500 pounds per square inch gauge, a toluene to propylene
mol ratio of 1:1 to 10:1 and a liquid hourly space velocity
of one to six volumes of hydrocarbon per volume of cata
6
taining one to ?ve Weight percent ?uorine, based on the
total catalyst, under alkylation conditions including a tem
perature of 450° to 550° F., a pressure of about 500 to
about 1500 pounds per square inch gauge, a toluene to
propylene mol ratio of 1:1 to 3 :1 and a liquid hourly space
velocity of one to three volumes of hydrocarbon per
volume of catalyst per hour, and thereafter recovering a
product predominating in the meta- and para-isomers of
lyst per hour, and thereafter recovering a product pre
cymene.
dominating in the meta- and para-isomers of cyme-ne.
2. The process which comprises contacting a mixture 10
References Cited in the ?le of this patent
of toluene and propylene in the liquid phase with a silica
UNITED STATES PATENTS
alumina catalyst containing 20 to 30 Weight percent
alumina, based on the silica-alumina content, and con
2,584,103
Pines et al. ____________ __ Feb. 5, 1952
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