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Патент USA US3087874

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April 30, 1963
3,087,866
J. s. BURCH
RECOVERY OF OLEFINS FROM'C7TO C 9
CORRESPONDING OLEFIN-PARAFFIN
MIXTURES
Filed Dec. 9, 1960
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INVENTOR.
JOHN S. BURCH ‘
BY
United States Patent 0
,.
1C6
3,087,866
Patented Apr. 30, 1963
2
1
10 and are fed through line 10 to separation still 11. In _
3,087,866
RECOVERY OF OLEFINS FROM 0; T0 C9 CORRE
SPONDING OLEFIN-PARAFFIN MIXTURES
John S. Burch, Dickinson, Tex., assignor to Union
Carbide Corporation, a corporation of New York
Filed Dec. 9, 1960, Ser. No. 75,462
3 Claims. (Cl. 202-42)
this column, the hydrocarbon mixture is contacted With
acetonitrile, which had previously been pumped into‘ the
column from acetonitrile storage tank ‘20 through lines 21
and 10. The more volatile paral?neacetonitr-ile azeotropes
are removed from the top of the column through vapor
line 1K2 and are condensed in condenser 13. The conden
sate there flows through line 14 into decanter 15, where it
separates into an upper hydrocarbon-rich phase and a
This invention rel-ates to the separation of ole?n
paraf?n mixtures wherein the constituents contain from 10 lower acetonitrile-rich phase. The upper layer is with
drawn from the system through line 16 to‘ receiver tank
seven to nine carbon atoms, and particularly to the recov~
22 ‘and the lower acetonitrile layer is returned as re?ux to
cry of ole?n rich fractions from such hydrocarbon mix
column 11 through line 1-8. To maintain proper re?ux
tures. Still more particularly, the invention relates to the
on the column, a portion of the upper layer may also be
separation and recovery of relatively high boiling isomeric
ole?ns trom mixtures of their corresponding isomeric 15 returned to the column through line 24.
The amount of acetonitrile in the column is limited
para?ins by azeotropic distillation. While the process
to the extent that a separation between the acetonitrile
of the present invention is applicable to‘ any mixture of an
ole?n and its corresponding para?in, provided it contains
trom 7 to 9 carbon atoms, the mixtures herein shown are
hydrocarbon azeotropes and the concentrated ole?ns is
effected in the lower trays, and the concentrated ole?ns,
by-product hydrocarbon fractions of the well known 20 containing little or no acetonitrile, are removed through
line 19 ?rom the base of the column and collected in
Oxo Process. This is merely illustrative and not in
tended in any way to limit or restrict this invention. The
present invention is applicable to any corresponding par
affin-ole?n mixtures of hydrocarbons having from 7 to
receiver tank 23.
To compensate for minor losses of
acetonitrile by partial solution in the upper layer of decan
ter =15, ‘acetonitrile may be added intermittently from
9 carbon atoms, regardless of the source of the mixture. 25 storage tank 20‘ through lines 21 and 10. ‘In case of incom
Distillation of the products trom the hydrotormyla
plete water removal in dehydrating still 3, a slow bleed
tion of ole?ns yields a head fraction containing a mixture
of acetonitrile-water mixture can be taken from the lower
of the ole?n, its corresponding para?in and aldehydes.
layer of decanter 15 through line 17 to maintain anhy
drous conditions in column 111.
This occurs in the well known Oxo Process wherein ole
The invention can also be applied to a batchwise tech
?nic hydrocarbons are reacted with carbon monoxide and 30
hydrogen to produce an aldehyde-alcohol mixture.
A
portion of the ole?n raw material passes through the con
verter unreacted and. is removed with the aldehyde-alco
hol in the mixed product stream. Another portion of
nique. In this case, a mixture of the acetonitrile and the
ole?n-paraf?n mixture is charged to the kettle of a batch
still. The overhead product from the column is con
densed ‘and the liquid phases separated in a decanter.
the ole?n raw material is hydrogenated to the corre 35 The lower acetonitrile layer is returned to the column as
sponding saturated hydrocarbon by a side reaction in the
converter. The unreacted ole-?n and the by-product par
a?in, some cat the aldehyde and water are removed as a
heads traction on distillation of the converter product.
re?ux, together with sufficient upper layer to maintain
proper re?ux on the system. A stream from the upper
layer, consisting of a concentrate of the paraf?nic hydro
carbons, is also withdrawn to the product tank. When
This mixed hydrocarbon ‘fraction generally contains 50 40 separation of the para?‘inic component by this method is
essentially complete, the re?ux and product system is
to 55 percent of the unreacted ole?n, a concentration too
changed so that all the upper layer is returned as re?ux
low -for economic recycling to the converter. Resolu
to the column and all of the lower layer is withdrawn to
tion between the ole?nic and paraf?nic hydrocarbons
a second product tank. When the acetonitrile has been
cannot be made by fractional distillation because each
is a mixture of isomers of overlapping volatilities. The 45 stripped from the system in this manner, the still can be
shut down and the kettle liquid, consisting of enriched
usual methods of separation employed, such as extractive
ole?ns suitable for recycling to the Oxo Process, can be
distillation, solvent extraction and adsorption, are either
pumped from the system. The acetonitrile solvent, in
inoperable, economically prohibitive or of poor e?iciency
the second product tank, can then be returned to the
The present invention provides a means of separating 50 system for reuse with the next batch.
Acetonitrile can also be used as the aqueous azeotrope,
the unreacted ole?n from this mixture through the use of
containing 81.5 percent acetonitrile at the expense of
a relatively small quantity of a moderately priced en- 1
some of the separation et?ciency. Usage of this azeotrope
trainer, said entrainer being recycled with little make-up
would obviate the need of dehydrating still 3 in the ?gure,
required, and is adaptable to simple conventional carbon
steel equipment. The ole?n fraction so obtained can be 55 and would permit the base of separation column 11 to
operate at a lower temperature.
readmitted to the 0x0 Process without further treatment.
The following speci?c examples will serve to further
The preferred form of the invention involves its ap
when ole?-ns of seven or more carbons are involved.
plication to a continuous process and the use of acetoni
illustrate the present invention and are not to be construed
trile as the entrainer. The preferred form is illustrated
in the FIGURE‘.
as limiting the present invention.
Referring to the ?gure, the ole?nic-para?inic hydrocar
bon mixture is fed from storage tank ‘1 through line 2 to
the side of the dehydrating still '3. The base of this con
tinuous column is heated conventionally, resulting in the
'
EXAMPLE 1
A mixture of 200 milliliters recovered C9 hydrocarbon
(41 percent nonane, 54 percent. nonene and 5 percent
decanal) and ‘90 milliliters of acetonitrile (containing
removal of the hydrocarbon-water azeotropes through 65 0.25 percent water) was fractionally distilled through a
30-tray Oldershaw column. The distillate was conden
vapor line 4 and condenser ‘5 to decanter 7. After phase
sed and the lower (acetonitrile) layer was returned to the
separation, the Water layer is removed through line 8 and
column. Distilled fractions and the residue were analyzed
the upper hydrocarbon layer is returned as re?ux through
‘for the components, and the results are reported in
line 9 to dehydrating still 3. The dehydrated hydrocar
bons atcrernoved from the base of the still through line 70 Table I.
3,087,866
Table I
Composition, vol. percent, CHsCN free
basis
Head
Fraction
temp.,
CHHCN
° 0.
Percent
of total
Aldehyde
and
as
aldehyde
decanal
tree basis
Nonanes Nonenes
Cg charge
1 ____________________ ._
2 ______________ __
c5
2A (lower layer).
3 ______________ ._
66 —77
77 —78
55
—05
4.
5_.
7.5
7.5
_
_
_
9 ______________ __
_
Col.hold-up(ealc.
_
77
76
18
24
4.9
0.4
19
24
Nil ________________________________________ __
7.5
so
20
Nil
20
78
78
5..
7__
8__
Vol.
percent
nonenes,
7s -7s.5
78. 5
78.5—79
Residue _________________________ __
7.5
7.5
67
00
32
40
0.7
0.4
32
40
7.5
7. 5
7.0
64
45
40
34
55
50
1.9
0. 4
0.7
35
55
50
7.0
31
5.5
20
78
1.9
80
28.0
8
73
67
19. 2
1.9
90
as
Considering fractions 1 through 6 as the waste nonane 20
Table IV
fraction and fractions 7 through 9 plus the column hold
up and residue as the recovered nonene fraction, a dis-
v01. oieontained component,
Percent
tribution of the components of the sample appears in
milliliters
nfzlnilncé.
Table II.
‘1 5.13 ‘’
Aldehyde ornoN
Table II
25
Nonanes Nonenes
as
free basis
decanal
Vol. of contained component,
Percent
Hummers
?filgiriféé
and
Waste nonane fraction. __
Recovered nonene lractio
57. 2
19.2
4s. 5
54. 9
0. a
9.8
86'4
103'4
10'1
42
74
Aldehyde CInCN
Nonanes
Nonenes
as
free basis
30
Total ---------------- --
------- —
decanal
Waste nonane fraction _____ __
63.6
26. 2
1. 2
29
Recovered nonene fractionm
23_ 4
75 4
1L 4
76
T°ta1 ---------------- --
87-0
10115
A recovery
of 53 percent "of the contained nonenes, in_
'
a fraction of 74 ‘percent purity (on an aldehyde and ace
tonitrile free basis), was achieved. The recovered nonene
12-6 -------- -- 35 fraction also contained 97 percent of the
aldehydes
present in the original sample.
A recovery of 74 percent of the contained nonenes, in
EXAMPLE 3
a fraction of 76 percent purity (on an aldehyde and
acetonitrile free basis), was achieved. The recovered
A nonene-nonane mixture (48 percent nonane, 51 per
nonene fraction also contained 91 percent of the alde 40 cent nonene and 1 percent decanal) was separated into
hydes present in the original sample.
nonene-rich and nonene-lean fractions by continuous
azeotropic distillation with acetonitrile. The crude hydro
EXAMPLE 2
carbon mixture was introduced at the side of a continuous
A mixture of 200 milliliters recovered C9 hydrocarbon
(41 percent nonane, 54 percent nonene and 5 percent 45 column at a point approximately equidistant from the
decanal) and 90 milliliters wet acetonitrile (containing
20 percent water by weight) was fractionally distilled
top and bottom of the packed section. The column con
through a 30-tray Oldershaw column. The distillate was
a sharp temperature gradient in the lower sections of the
column, and the product stream from the base of the
tained a limited amount of acetonitrile, so that there was
condensed and the lower (acetonitrile-water) layer was
returned to the column. Distilled fractions and the resi 50 column contained no acetonitrile. The overhead stream
due were analyzed for the components and the results are
from the column was condensed, and the liquid layers
reported in Table III.
separated. The lower (acetonitrile) layer and a portion
Table III
Composition, vol. percent, CH;ON tree .3‘ Vol.
basis
percent
CH3CN
Head
Fraction
nonenes,
‘301119.,
° 0.
Percent
of total Nonanes Nonenes
C9 charge
1 ____________________ --
66
31. 5
7. 0
7. 5
6. 5
7. 5
7. 5
7. 5
7. 5
7. 5
62
59
58
58
53
54
54
45
38
41
42
42
47
46
46
55
C01. hold-up (calm) _ . - __________ __
7. 0
30
Residue _________________________ ._
27. 5
15
1A (lower layer)
._
2
7. 0
Aldehyde
and
as
decanal
aldehyde
free basis
2. 5
32
Nil
Nil
Nil
N11
Nil
N11
N11
0. 4
38
41
42
42
47
46
46
55
70
0. 4
70
67
17. 6
82
________ __
_
‘Considering fractions 1 through 8 as the waste nonane
fraction and fraction 9 plus the column hold~up and resi
due as the recovered nonene fraction, a distribution of the
components of the sample is provided in Table IV.
of the upper (hydrocarbon) layer were returned to the
column as re?ux. The remainder of the upper layer was
collected as overhead product. The column was operated
so that the overhead product and the base product streams
3,087,866
51
6‘
were removed at the same rate‘.
Make-up acetonitrile
and residue as the recovered nonene fraction, a distribu
was added occasionally to the feed. Summarizing:
Overhead product:
Grams
Nonanes _____________________________ __ 2,166
Nonenes '"
tion of the components of the sample is collected in
Table VI‘
Table VI
5
‘1,07 1
Aldehydes, as decanal __________________ ..._
22
.
Vol. of contained
component
milliliters
,
Percent
nonenes,
‘
aldehyde
and
Total ____ __, ____________________ ______ 3,259
____.___.
7“ _‘ ‘
Aldehyde onto»;
Nonanes Nonenes
as
free basis
10
dceanal
'
Base
Product:
"
Nonanes "'"‘“"""'
"'""'"-“'"‘"
887
_, _ _ _ _ _ _ _ _ _ __
2,547
Aldehyde, as decanal __________ __,_V_____V___
53
Nonenes
____ _ _ _ _ _ _
Total
Total recovery" """ '7 """""" "‘
"
"
'
Recovered nonene fraction...
'
202. 1
94. 9
-
Total ------------ -----~
297-0
"‘
'
90.0
1. 9
277. 5
31
33. 6
.
’
1
"
Waste nonane fraction ..... _-
3 487 15'
""“""'""‘"’ """" """ """ '"
'
75
.
367-5
35-5
"a ----- -
A 200 milliliter portion of the waste nonane fraction
(69 percent nonane, 30.6 percent nonene and 0.4 percent
'
dacanal) was then mixed with 50 milliliters of aceto
6’746
nitrile and distilled through the same column in the same
1 99 Percent
c
a
‘
-
-
'
20 manner as in the initial distillation.
The base product stream contained 70.4 percent of the
‘
Analyses of the re
sulting fractions is collected in Table VII
Table VII
Composition, vol. percent, CHzCN tree
basis
Head
Fraction
Vol.
percent
nonenes,
temp,
.
° 0.
Percent
of total
Nonanes Nonenes
CHKCN
Aldehyde
as
and
aldehyde
decanal
tree basis
C9 charge
1 ____________________ __
77.0-77.9 ‘
11.7
84
16
0.4
16
2.-.
a
4.-5_-_
77. 9-78. 0
78.0
7s. 0
78.0-78.2
7s. 2
78.2
12. 2
12.2
12. 2
12. 5
12. 5
22
25
26
2s
27
36
Nil
Nil
0. 7
Nil
0. 7
Nil
22
25
26
28
27
7.5
7s
75
73
72
72
64
0.7
55
45
Nil
45
18.5
45
54
0.9
55
Residue _____________ .- __
nonenes present in the original sample, and had a nonene
purity of 73 percent, on an aldehyde-free basis. This
:36
Considering all the distilled fractions and the column
hold-up as a waste nonane fraction and the residue as
stream also contained 71 percent of the aldehyde vpresent 40 a recovered nonene fraction, a distribution of the com
ponents is collected in Table VIII, when calculated on the
basis of the entire nonane fraction from the previous
A total of 266 grams of acetonitrile was required in
this separation of which 165 grams were recovered by
distillation (294 milliliters).
stripping from the column at the end of the run. The
remaining 101 grams of acetonitrile left the system with
Table VI”
the overhead product, from which it can be recovered 45
in the original sample.
extraction
either by with
subsequent
water. ‘distillation of this stream or by
V°1-ofcmgf??geggmpmemi aidehgaé
8.11
EXAMPLE 4
.
Aldehyde ornoN
_ _
50
A mixture of 700 milliliters recovered C9 hydrocarbon
(41 percent nonane, 54 percent nonene and 5 percent
'
‘ '
'
'
' '
decanal) and 50 milliliters acetonitrile (containing 0.25
Nonenes
as
freebasls
decanal
percent water) was fractionally distilled through a ‘SO-tray
Oldershaw column.
Nonanes
The distillate was condensed and 55
W
aste nonane fraction _____ .Recovered nonene fraction___
178.2
2“
2H
0.5
Tml ---------------- --
2°“
90-2
1 2 -------- ~
60.8
0.7
25
55
the lower (acetonitrile) layer was returned to the column.
Distilled fractions and the residue were analyzed for the
components and the results are collected in Table V.
Table V
The nonene recoveries and the purities of the nonene
fractions are shown in Table IX for the initial distillation
Composition, vol. percent, CHsCN tree
basis
Head
Fraction
temp,
° 0.
CHSCN
Percent
oi total
Nonanes Nonenes
Ca charge
6
._
Vol.
percent
nonenes,
0.3
80
65 -66.8
13. 7
14.0
14. 0
14.0
72
69
65
47
26
31
35
53
66. 8~67.5
7O
Aldehyde
as
and
aldehyde
decanal
free basis
__________________ __
2
Nil
Nil
Nil
20
27
31
35
53
14.0
30
Nil
70
C01. hold-up (cale) . ._ .......... __
3. 3
19
81
Nil
81
Residue ______________________ _-_-__
26. 7
8
74
17. 6
90
Considering fractions 1 through 4 as waste nonene frac
tion and fractions 5 through 6 plus the column hold-up
singly and for the combined initial distillaton and subse
quent redistillation of the nonane fraction.
3,087,866
Table IX
Table XI
Initial
distillation
N onene recovery, vol. percent ________ __
75. 5
Redistillation
of nonane
fraction
Combined
distil~
laticn
8.0
Vol. 01' contained
components, milli~
liters
5
Heptanes Heptenes
83. 5
Percent
heptenes
CIIQON
free basis
Nonene purity, v01. percent of recovered
nouenc fraction,
aldehyde and
CHaCN free basis __________________ -_
Aldehyde recovery, vol. percent ...... __
75
95
55
1
70
96
Waste heptane tract-ion _____________ ._
217.9
70.1
24
Recovered heptene fraction _________ __
63. 8
248. 2
80
Total _________________________ _-
281. 7
318. 3
__________ ._
10
‘EXAMPLE 5
,
_
_
A recovery of 78 percent of the contained heptenes, 1n
, A he]?ten'~"‘hei3tan_e mlxtllre (40 Pement h?ptane and 51
percent heptene), simulating the recovered hydrocarbon
a fraction of 80 percent purity (on an acetonitrile-frce
basis) was achieved_
fractions obtained as a by-product from the hydroforrnyla- 15
‘It is to be understood that the invention is not to be
limited to the exact details of operation shown and
described, as obvious modi?cations and equivalents will
be apparent to one skilled in the art, and the invention is,
tion of heptenes to produce octyl alcohols, was prepared
by the partial hydrogenation of a sample of heptenes. A
mixture of 600 milliliters of the heptene-heptane mixture
and 50 milliliters of acetouitrile was fractionally distilled
through a packed column. The distillate was condensed 20 therefore, to be limited only by the scope of the appended
claims.
and the lower, acetonitrile layer was returned to the col
gWhat is claimed is:
umn. Distilled fractions and the residue were analyzed
1. The method of separating corresponding para?ins
for the components and the results ‘are collected in Table
and ole?ns from mixtures comprised of hydrocarbons
25 containing from seven to nine carbon atoms by distilling
said mixture with acetonitrile as an azeotrope entrainer
Table X
Fraction
Head
temp., ° 0
Percent
Composition, vol.
percent, CHQON
of total 01
free basis
charge
. .
_
and removing the paraf?nic fraction as the heterogenous
azeotrope from the entrainer.
2. The process of claim 1 where the admixture to be
separated is composed of isomeric nonenes and their cor
._
Heptanes Heptencs
16.0
15. 7
16. 3
74
78
75
6. 2
4G
54
45. 8
17
83
.
Residue _________ __
responding isomeric nonanes.
3. The process of claim 1 where the admixture to be
separated is composed of isomeric heptenes and their cor
26
22
25
35
responding heptanes.
References Cited in the ?le of this patent
Considering fractions 1 through 3 as the waste heptane
fraction and the column hold-up and residue as the re
covered heptene fraction, a distribution of the components 4 0
of the sample is presented in Table XI.
UNITED STATES PATENTS
2,401,282
Welling _____________ __ May 28, 1946
2,679,472
Tooke ______________ __ May 25, 1954
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