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Патент USA US2407214

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Patentecl Sept. 10, 1946
2,407,214
UNITED STATES PATENT OFFICE
2,407,214
PRODUCTION OF AN AVIATION OR MOTOR
FUEL 0R AN AVIATION OR ll/IOTOR FUEL
CONSTITUENT
Stanley Francis Birch, Frederick Arnold Fidler,
and Leslie Senior Thornes, Sunbury-on
Thames, England, assignors to Anglo-Iranian
Oil Company Limited, London, England, a
British joint-stock corporation
No Drawing. Application September 16, 1943, Se
rial No. 502,644. In Great Britain July 1, 1942
1
3 Claims. (Cl. 2604-666)
The invention relates to the production of
2
cyclopentane from cyclopentadiene andiparticu
engine testing unit as against a relative toluene
performance of 170 (in the same terms). The
larly from the cyclopentadiene present in the so
called crude benzol forerunnings of coal tar dis“
physical properties of a representative sample of
cyclopentane produced according to the process
tillates.
In the treatment of these crude benzol iore
runnings for the removal of carbon disulphide as,
for example, in the treatment with ammonium
sulphide for this purpose, the cyclopentadiene is
of the invention are as follows:
B. P. at 760 mm ___________________ __°C__
Cottrell spread _______________________ __
20
'
49.4
Nil
-
n-D- _________________________________ __
1.4063
polymerised to dicyclopentadiene and in accord-, 10
ance with invention the latter is then depoly~
d210- __________________________________ -i 0.7456
merised to produce cyclopentadiene again, and
Sulphur
content _______________ __% wt__ 0.0004
the cyclopentadiene is then hydrogenated to form
Octane number (C. F. R. motor method) __
84
cyclopentane, a substance having an octane num
ber of 84 (C. F. R. motor method) and thus 15
According to the invention moreover the crude
adapted for use as an aviation or motor fuel or
concentrate with its content of dicyclopentadiene
constituent thereof,
obtained by polymerisation of the crude benzole
The invention has among its objects to pro
forerunnings with its content of cyclopentadiene,
duce cyclopentane under conditions of practical
the concentrate having an‘ approximate boiling
convenience and e?iciency by the ‘hydrogena 20 range of 75° C.-175° C. is advantageously treated
tion of cyclopentadiene, and to avoid the prac
e. g. with ammonium sulphidefor removal of
tical disadvantages attending the reaction due to
carbon disulphide, and thereupon topped to re
the considerable amount of heatdeveloped.‘
According to the invention cyclopentadiene is
move the light‘ends boiling in the approximate
boiling range of 73° C.-80°‘ C. The light ends
hydrogenated in the presence of a diluent present ‘
consist mainly of benzene with some unsaturated
in such considerable proportion as to avoid the
hydrocarbons and sulphur compounds, for ex
ample thiophen. The residue after removal of
the light ends consists chie?y of dicyclopenta
practical disadvantages usually attending the re
action by reason of the considerable heat evolved
under usual reaction conditions, the diluent func
tioning as a moderating or stabilizing agent.
Thus according to the invention high concen
‘ trations of hydrogen may be used as a moderat
diene by reason of the ease with which such
cyclopentadiene in the benzole iorerunnings is
polymerised. The cyclopentadiene in the crude
forerunnings may however be polymerised rap
ing or stabilising diluent in considerable excess
idly and successfully to dicyclopentadiene by
of the small proportion that is consumed in the
contact with‘dilute acid.
a
reaction; or instead of or in addition to high 35
The dicyclopentadiene may be obtained in a
concentrations of hydrogen, benzol or the light
pure state by fractionation under vacuum in an
ends of the benzol iorerunnings may be used as
e?icient column. The material is a solid in the
the diluent, or alternatively or in addition the
form of colourless needle crystals at ordinary
cyclopentane product of the process may be so
temperature and has a boiling point of 88.7“ C. at
used. The use of the light ends as the diluent
50 mm. pressure.
has moreover the further advantage that its con
According to the invention moreover dicyclo
tent of benzene is re?ned in the process becom
ing thereby free from sulphur.
The cyclopentane produced under the condi
pentadiene may be de-polymerised at tempera
ture of l55-170° C. which may be carried out
tions described is particularly pure and gives 45 in a column packed with ironturnings or similar
material of iron or steel functioning as a catalyst
excellent performance as a fuel in a standard
and the overhead product taken off slowly at a
air-cooled aero-engine testing unit. This is in
column head temperature of 40° C.—42° C. The
dicated by comparison of the relative cyclopen
overhead product of distillation and de-poly
tane performance of 240 (in terms of lbs. per
square inch B. M. E. P.) in a standard aero 50 merisation is cyclopentadiene and is substan
2,407,214
or
4
tially sulphur-free. By suitable control of the
distillation the rate of production of cyclopen
an appreciable quantity of solid residue being left
tadienev may be adjusted to the rate of hydro
genation in the hydrogenation units to which it
passes. By such means intermediate storage and
re-polymerisation to the dimeride are avoided.
The invention comprises the processing condi
tions hereinafter described.
In carrying the invention into effect the cyclo
in the still.
This residue may even amount to
four times the amount of the residue remaining
after vacuum distillation of crude dicyclopentadi
ene. The production of these higher polymers
we have found may be reduced appreciably by
supplying the dicyclopentadiene to the depoly
meriser substantially at the rate at which de
polymerisation is required and that the de-pcly
pentadiene may advantageously be hydrogenated 10 meriser itself should be no larger than is neces
in the vapour phase over a hydrogenation-dehy
drogenation catalyst of the molybdenum oxide
alumina type, and under the following condi-v
tions:
Temperature ________________________ __ 400° C.
Pressure ______________________ __ 200 lbs/sq. in.
Oil input rate (total oil feed) _1.0 volumes/volume
of catalyst/hour.
Hydrogen recycle rate _____ __ 5000-6000 C. F./B.
of oil feed.
The feed is advantageously diluted with an in
ert material in such a proportion as to moderate
or stabilise the reaction conditions. The presence
of sulphur has however no deleterious effect on
sary for this purpose. In this way prolonged
heating in the still is avoided.
It is known moreover that the polymerisation
of the dicyclopentadiene is offset by packing the
still with steel turnings or steel wool, whereby a
large surface area of iron is thus provided which
serves as a depolymerising catalyst.
Alternatively under the conditions indicated,
the crude concentrate in the state of vapour and
without preliminary removal of the light ends
may be fed to a de-polymeriser consisting of a
vessel packed with iron or steel wool or other
convenient packing offering a large surface, and
maintained at a temperature for example of
200° C.-300° C. and at a moderate pressure. The
vapour leaving the depolymeriser may be con
densed and fed to the hydrogenation unit as liq
uid, or the vapour may be mixed with hydrogen
ends may conveniently be used as a moderating
and passed together in vapour phase directly into
or stabilising diluent. Under these conditions the
further advantage results that the benzene is 30 a vessel containing an hydrogenation catalyst
such as molybdenum oxide-alumina. This
re?ned in the same operation and the complete
method of operation has the advantage that the
preliminary removal of carbon disulphide is
benzene diluent is already present in the vapour
thereby rendered unnecessary.
and that no further dilution may be necessary.
Alternatively cyclopentane, either as produced
Advantageous process conditions are indicated
in the process described or derived from another
the molybdenum oxide-alumina hydrogenation
catalyst and thus the previously removed light
source may be used as the moderating or stabilis~
ing diluent.
No limitation is involved to the use of the type
in the following examples:
Example 1.—The light ends with their content
of benzene was distilled from 388 liters of the
crude concentrate resulting from polymerisation
of hydrogenation catalyst indicated. Thus the
process may be carried out in the liquid phase in 40 of benzol forerunnings. The greater part came
over at atmospheric pressure, but in order to
the use of a nickel catalyst at a temperature of
avoid overheating in the still and depolymerisa
from 50° C.-100° C. If Raney nickel however be
tion of dicyclopentadiene at this stage, the last
used as the catalyst or any other catalyst liable
traces were removed under vacuum at a temper
to sulphur poisoning under the reaction condi
tions, it is necessary in order to avoid poisoning 45 ature below the depolymerising temperature.
The sulphur content of the light ends recovered
of the catalyst that the material processed should
as overhead was 0.102 per cent by weight, the
?rst be rendered sulphur-free. In such a case
original charge of concentrate was 388 litres and
cyclopentane itself is a particularly advantageous
the light ends taken overhead to 120° C.-208 litres.
moderating or stabilising diluent, and thus if it
The residue consisting chiefly of dicyclopenta
be desired to obtain a pure cyclopentane, cyclo
diene was then heated to 160° C.—180° C. at at
pentane itself may advantageously be used as
mospheric pressure when cyclopentadiene dis
diluent in preference to benzene, whereby the
tilled off at 2.3 litres per hour.
necessity of subsequent distillation to separate
The following were the physical properties of
the benzene diluent is avoided.
The use of benzene has however substantial
the cyclopentadiene produced:
advantages as a diluent inasmuch as on its dis
charge from the process it is substantially free
from sulphur as well as frome ole?nes, although
it contains a small percentage (approximately
5%) of high boiling residue, probably derived
B. P. at 760 In. In ___________________ __°C__ 40.3
n23 ___________ ___ _____________________ __ 1.4450
20
11-4- __________________________________ __ 0.8044
from dicyclopentadiene. In this way the cyclo
pentadiene is hydrogenated and the benzene is
re?ned in one operation. Furthermore where the
The cyclopentadiene was diluted with four
ultimate object is to produce an aviation spirit
times its volume of the light ends and this total
blending constituent the mixture of benzene and 65 oil feed passed over a 5% molybdenum oxide-on
cyclopentane after removal of the high boiling
alumina catalyst at a temperature of 400° C., and
residue may together serve as an aviation fuel
a hydrogen pressure of 200 lbs/sq. in. The total
constituent without further treatment, the ben
oil feed over the catalyst was 1.0 v./v./hr. When
zene being restricted to the permitted proporion
a sufficient quantity of the hydrogenated product
that may be required by the speci?cation. The
had been collected, this was used as a diluent for
conditions of hydrogenation referred to are such
subsequent hydrogenations, the cyclopentadiene
that the benzene is not itself hydrogenated.
content of the feed to the hydrogenation unit al
We have found that during de-polymerisation
ways being maintained at 20% by volume. By
a considerable amount of the dicyclopentadiene.
appears to be further polymerised, resulting in 75 constantly recycling the products, the cyclopen
2,407,214
5
tane content of the ?nal material was approxi-
late, comprising the steps of subjecting the fore‘
mately 60% by volume.
runnings to polymerisation, and producing a con
centrate having an approximate boiling range of
75° to 175° C., distilling the said concentrate for
the separation as overhead of the light ends boil
Litres
Cyclopentadiene produced _______________ __ 99
Hydrogenation products _________________ __ 157
Cyclopentan'e produced __________________ __ 94
Re?ned benzol ___________________________ __
ing approximately at 78° to 80° C., consisting of
benzene mainly, together with some unsaturated
63
and sulphur compounds, and a residue fraction
The benzol during the processing was desul
as bottoms containing dicyclopentadiene, subject
phurised (sulphur content 0.0007 per cent by
10 ing said residue fraction to a depolymerising oper
weight), and contained approximately 5% of high
boiling residue.
ation to convert dicyclopentadiene in said fraction
to cyclopentadiene, and directly subjecting cyclo
Example 2.--The crude material was dropped
pentadiene so obtained to hydrogenation in ‘the
into a flask maintained in an oil bath at 240° C.
presence of a temperature moderating and reac
250° C. By this means the light ends and dicyclo;
pentadiene were flashed off from a small amount 15' tion stabilising diluent, to yield the cyclopentane
product, said depolymerising operation being car
of gummy residue. The vapours from this ?ask
were passed through an iron tube of 56" in length,
ried'out in a column packed with iron or steel in
a divided state such as small pieces or ?bre to
and an internal diameter of 11/2", and the tube
yield substantially sulphur-free cyclopentadiene
was packed with steel wool. The tube was‘ elec
trically wound and the products were passed 20 as overhead at a column head temperature of 40°
through a water-cooled condenser into a flask
to 42° C. at a rate corresponding to the required
feed rate of the cyclopentadiene in its hydrogena
fitted with a solid CO2 trap. The material was
tion.
passed through the tube at two di?erent temper
atures and at di?erent rates. The following table
2. A process for the production of cyclopentane
gives the properties of the original material and
from the benzol forerunnlngs of a coal tar distil
the various products obtained:
late, comprising the steps of subjecting the fore
runnings to polymerisation, and producing a con
Table
centrate having an’ approximate boiling range of
75° to 175° C., distilling the said concentrate for
Origi
na
mate_
rial
Run 1
Run 2
Run 3
30 the separation as overhead of the light ends boil
Run 4
ing approximately at 78° to 80° C., consisting of
benzene mainly, together with some unsaturated
and sulphur compounds, and a residue fraction as
Conditions
bottoms containing dicyclopentadiene, subjecting
Temp. of tube ____ __°O.. ...... __
210 290e300 290-300
290-300
said residue fraction to a depolymerising opera
Rate of addition of con
centrate. __. _ . .cc./hr_ _ ______ _ .
93
74
141
233
0. 186
0. 148
0. 282
0. 466
0. 8845
0. 8400
0. 8400
0.8380
56
46
47
47
Vol. of concentrate/v01.
tion to convert dicyclopentadiene in said fraction
to cyclopentadiene, and subjecting cyclopenta
‘
of tube/hour _________________ _ _
diene so obtained to hydrogenation in the pres
ence of a temperature moderating and reaction
Properties of product
Sp. gr.
60° F _______ -- 0.9150
I. B. P. ‘’ C ........... __
75.5
__
.
.
.
__________ __
79. 0
64
53
52. 5
52. 5
81. 0
84. 0
88.0
92. 5
98. 0
109. 5
153. 0
166. 5
66. 5
68. 5
72
76. 5
81. 5
87
94. 5
120
54. 5
55. 5
57. 5
59. 5
62. 5
66
70
75
54
55
57
59
62
65. 5
70
75
54
55
56. 5
58. 5 45
61
64. 5
69
74. 5
167. 5
167
I 80
80. 5
80
170.0
170
91
90. 5
88. 5
174. 5
176
173. 5
175
175. 5
212
221
252
249
260
Bromine number Fran
cis) __________ __(_____ -_
stabilising diluent, to yield the cyclopentane prod
uct, said hydrogenation of the cyclopentadiene
50
product being carried out in the use of a molybde
num oxide-alumina type of catalyst at a temper
ature of the order of 400° C., at a pressure of the
order of 200 lbs. per square inch, at an input rate
of the order of 1.0 volume/volume of catalyst/
hour in the’ presence of hydrogen in substantial
excess of the proportion taking part in the reac
tion.
,
"
3. A process for the hydrogenation of cyclopen
tadiene for the production of cyclopentane, com
prising diluting the cyclopentadiene with not sub
stantially less than four times its volume of an
726 g. of the product from run 4 was distilled,
and the yield of cyclopentadiene was found to
be 271 g., or 38 per cent by weight. This indicated 55 inert diluent material to serve as a reaction tem
perature moderating and reaction stabilising dil
that almost complete de-polymerisation had oc
uent and carrying out the hydrogenation reaction
curred, since the dioyclopentadiene content of the
in the use of a molybdenum oxide-alumina type
starting material was 39 per cent by weight. The
of catalyst at a temperature of the order of 400°
mixture so obtained was fed as before to a hydro
genation unit, and the products were cyclopen 60 C., at a pressure of the order of 200 lbs. per square
inch, at an input rate of the order of 1.0 Volume/
tane and re?ned benzol.
7
~
‘
volume of catalyst/hour and in the presence of a
It will be seen from the table that 210° C. is not
quantity of hydrogen inthe proportion of at least
a sui?ciently high temperature to effect complete
de-polymerisation under the conditions indicated,
but the reaction was complete at all rates of ad
dition used at 290° C.-300° C. '
We claim:
.
1. A process for the production of cyclopentane
from the benzol forerunnings of a coal tar distil
05
5000 cubic feet of hydrogen per barrel of feed, to
yield the cyclopentane product.
STANLEY FRANCIS BIRCH.
FREDERICK ARNOLD FIDLER.
LESLIE SENIOR THORNES.
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