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Патент USA US2399882

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2,399,882
Patentcd May 7, 1946
UNITED STATES PATENT ‘OFFICE
2,399,882
OLEFIN CONCENTRATION
Charles E. Morrell, West?eld, James K. Small,
Union, and James H. McAteer, Cranford, N. .L,
assignors to Standard Oil Development Com
pany, a corporation of Delaware
No Drawing. Application-November 3, 1944,
Serial No. 561,842
13 Claims. (Cl. 260-6815)
the acetylenes dissolved therein. Although the
This invention relates to improvements in
reaction is quite complex, and may involve also
processes for concentrating oleilns and relates
copolymerization and reaction with‘ components
particularly to improvements in processes where
of the copper solution, the process is referred to
cuprous salt solutions ‘are used as extraction
herein for purposes of simplicity as a “polymeri
agents in the separation and concentration of
zation" and the products as polymerization prod-v
ole?ns and dioleilns.
ucts. The polymerization products from such a
Cuprous salt solutions, especially these con
process are quite varied in nature. Some of the»
taining ammonia, for example one containing 2
products are liquids which are readily removed
to 5 mols cuprous copper, 10.5 to 12 mols am
monia and 4 mols of acetic acid and having a 10 from the copper solution by settling or by wash
ing with an appropriate solvent such as hydroe
pH value of 10.5 to 12.5 have been extensively
carbon liquids. Liquid polymers of this type pre
developed for concentrating ole?ns and diole
dominate when ethyl acetylene is the main acety
ilns, for example butadiene from hydrocarbon
lenic constituent of the crude butadiene. When
mixtures. Cracked petroleum hydrocarbons con-,
tain crude butadiene and also small but varying 15 vinyl acetylene is present in large amounts, some
plastic or semi-solid materials are also formed.
amounts of acetylenic materials having the fol
lowing boiling points:
. These may be removed by ?ltration.
It has been found, however, that in addition to
the above types of products some of the products
of acetylene polymerization are quite soluble in
Vinyl acetylene _________________ _r___...... 41.0
water, therefore also in the aqueous copper solu
Ethyl acetylene ______________________ __ 47.7
tion, and are not readily extracted with hydro
Dimethyl acetylene __________________ __ 80.4
carbon solvents. They are not removed from the
Butadiene__._.._ ______________________ __
24.06
solution by ordinary filtration. These soluble
The total acetylene content of butadiene-con 25 products have not been too well identi?ed since
they appear to be a rather complex mixture of
taining 04 fractions varies as to the process and
compounds some of which contain oxygen, nitro
feed stock used in the preparation of the said
gen, carbon and hydrogen. At least a portion of
hydrocarbon fraction. Steam-cracked stocks
these soluble products are highly objectionable in
produced at temperatures up to about 1250° F.
usually contain less than about 0.1 weight per 30 the butadiene extraction process since they are
surface-active materials which tend to promote
cent (1000 parts per million) of acetylenes in_the
C4 cut. Catalytic dehydrogenation of butenes in
foaming of the solution, when contacted with a
normal adiabatic operation also produces rela
gas, and emulsion formation when the solution is
tively low acetylene C4 cuts. Cracking at higher
contacted with a liquid hydrocarbon. This tend
temperatures up to 1400° F. with steam or air 35 ency to produce foaming and emulsi?cation in
increases the acetylenes to about 0.25 to 1.65%,
the extraction systems is at least in part believed
cracking with air apparently giving the larger
due to the fact that these materials greatly lower
increase. The use of still higher temperatures of
the interfacial tension of the solution with re
spect to hydrocarbons. .
I
about 1400-1800° F‘. in regenerative furnaces pro
duces a C4 cut containing from 2 to 5% acet 40 According to this invention it has been found
ylenes.
that these surface-active materials can be re
In the concentration of butadiene it is desir
moved from the used aqueous copper solution,
able to remove these acetylenes in such a man
and the foaming and emulsiflcation tendencies
ner that they are not present in the puri?ed buta
of the solution thereby decreased, by contacting
diene but due to boiling points only methyl and 45 the solution with a variety of, finely divided, in
dimethyl acetylene can be separated sufficiently
soluble materials, especially those which are
by distillation. The dimethyl acetylene contains
known to possess high adsorption capacities.
no acidic hydrogen and does not form copper
These materials include the natural and synthetic
acetylides. Vinyl and ethyl acetylene together
silicates of metals of groups II and III, the dia
with butadiene are readily removed from the hy 50 tomaceous earths, the charcoals, and the like.
Especially useful in this connection are magnesi
drocarbon mixture by the use of a copper solu
tion. One procedure which is in common prac
um silicates, aluminum silicates, andv activated
carbon. Ion exchange adsorptive substances,
tice for preventing these acetylenes from con
both organic resins such as the “amberlites”
' taminating the butadiene product is to heat the
solution under appropriate conditions (prefer 55 and inorganic agents such as the zeolites, may
also be used. Commercial grades of these ma
ably after desorption of butadiene) to polymerize
-
°F.
Methyl acetylene ____________________ __ -9.8
2
terials such as Magnesol (a magnesium silicate)
and Super Filtrol (an aluminum silicate) are
beneficial. Activated Alumina and silica gel are
inferior to the above-mentioned preferred sub
nitrogen gas through a wet test meter, then
through a gas scrubbing bottle containing aque
stances.
the solution to be tested. The gas then ?ows
’
ous ammonia of proper concentration to provide
the same partial pressure of ammonia as that over
I
The effect of adsorbents on the surface tension
of a used solution is illustrated in the following‘ ~
through a rotameter and ?nally into a 500 cc.
Exam“: I
Portions of a solution of cuprous ammonium
acetate which had been used in the concentration
graduated cylinder containing v'15 cc. of the cop
per solution to be tested. The cylinder diameter
is 2 inches. The 7-mm. glass tubing carrying ni~
trogen gas into, the copper solution extends 1 inch
below the surface of the solution and has a 1/2-inch
of butadiene from'a highly cracked petroleum C4
fraction containing about 2.5% actylenes, and
which had developed serious foaming and emul
minute; The height to which the solution foams
example:
fritted glass tip. Nitrogen is passed through the
solution at a rate of 750 cc. per minute for one
‘in the cylinder and the length of time ‘required
sifying characteristics, were shaken at room tem~
. for the foam to break are observed.
perature with 1/2 volume of a powdered adsorbent,
centrifuged to remove the adsorbent, and then
tested for interfacial tension against a paramnic
oil at 25° C. in a du Nuoy interfacial t'ensiometer,
with the following results:
Solution
'
Tests are
carried out at room temperature, 32° F. and 110° F.
Used solution from a plant operating on a C4
fraction .containing 2.5% acetylenes, foamed to
20 the top of the graduated cylinder in less than a
minute, and requires 5 minutes to break. After
treating the same solution with Magnesol and
removing the Magnesol by ?ltration, the solution
foams to only 1/2 the height of the cylinder, and
25 the foam completely breaks in 30 seconds.
Other examples of the effectiveness of Magnesol
Solid adsorbent
Fresh copper solutiom
User;Jcopper solution..
and other treating agents are as follows:
0 .............. ._
a]
EXAMPLE III
.
“Amborlite" ‘base exchange) _
"Ambcrlite” anion exchange).
Agtivate?lyglumina ......... _.
Attepsulgus clay ............. _.
_
U
u
Samples of used copper solution from a pilot
30
plant extracting butadiene from a cracked petro
0!! - _ - _ _ _ _ l - - _ _ _ _ -~
leum C4 fraction containing 0.28% acetylenes
were subjected to the following emulsion test: 10
The solution may be contacted with these ma
terials in a number of ways. One of these con
cc. of the copper solution were mixed with 5
85 cc. of para?inic naphtha (both at 15° F.) and
sists of slurrying the solid contact agent in this
solution, which may be either hot or cold, prefer
ably after the butadiene has been desorbed and
either before or after the copper solution insolu
ble polymers, have been separated, and subse
quently passing the slurry through a ?lter to re
move the solid material. Alternatively, the solid
shaken vigorously for 30 seconds, then allowed
to stand at 15° F. for a maximum time of 5
minutes. The time was observed at which the
emulsion was completely broken. When this did
not occur in 5 minutes, the per cent of oil layer
separated at that time was measured. Solution
circulation in the plant was maintained at 50
gallons per hour. The total solution stream was
desorbed of butadiene at about 170° F. (:10° F.)
then passed through a soaking drum at 180° F.
‘for 40 minutes residence time, then passed
through a ?lter (which was by-passed for part
treating agent may be used as a precoat on the
?lter and the solution simply passed through this
?lter. In another type of procedure the contact
ing agent in pill or lump form may be placed in a
tower on supportinggrids and the solution circu
lated through this tower.
Extremely small
of the run) then through coolers, then scrubbed
with liquid butenes to remove oily polymers, and
marked effects in reducing the emulsi?cation and 50 then recycled to the absorber and stripper tower,
through which it was passed countercurrent to the
foaming tendencies of the used solutions, as in
dicated in the examples below.
C4 fraction and to recycled butadiene, respectively.
both hydrocarbon streams being maintained in
After a certain period of time the solid agent
liquid phase in the tower. The results of emul
becomes spent and ineffective due to saturation
sion tests on solution samples taken at the de
of its surface with the adsorbed surface active
sorber inlet, and the nature of the ?ltration, are
material. Before this condition is reached fresh
given in the following table:
contact agent should be added to the extraction
system. The contact agent may be regenerated
Emulsion test
in the following manner: It is ?rst washed with
aqueous ammonia to remove the copper retained 60
amounts of the solid adsorbent can produce
by the agent and then revivified for further use
by any of the following methods.
-
Filter precoet
_ Hour
(1) subjection to the action of high tempera
ture steam.
,
I
Time.
512%,?
rated
_
(2), Burning of the material to regenerate it
65
900gm. Filter Cel ......................... ..
0-116
.
70
__________ ._
20
No ?lter ................................... _.
116-262
.......... ..
165
215
20
34
in the same manner as clay used in lubricating
oil treatment is regenerated.
The following example shows the eifectiveness
of one of these contact agents, namely, Magnesol
when used in operation.
.
70
450 gms Magnosol.
v
450 ' ‘Filter OeiIIIIIIIIIIIIIIIIIIIIII
EXAIPLI II
A test has been devised to measure the tendency
of the copper solvent to foam when a gas is
passed through it. The test consists in passing 76
.
'
_
llilgms. Filter Oel, fresh ?lter each 24 hours...
ear-g1)
50
262 """" "ii
271-287
785
.... _.
1. 5
287-368 .......... _ .
' l
357
l. 5
1. 6
2,899,882
3
comprises treating the said mixture or hydrocar
EXAMPLE IV
In another pilot plant run to extract butadiene _
from a cracked petroleum Ci fraction containing
bons containing'diole?ns' and acetylenes with a
> cuprous salt solution, separating the cuprous salt
solution‘ ‘with the acetylenes and diolefln dis
1.8% acetylenes, in which the absorber and strip?‘ '
solved therein, heating the cuprous salt solution
to separate the diole?n and to form polymers,
treating the'said cuprous salt solution contain
ing the polymers with a solid material having high
per were operated with the hydrocarbons in the
vapor phase, and the circulation of the solution
was the same as described in Example HI, it was
observed that ?ltration of the solution through
adsorption capacity, separating the solid material
a Magnesol precoat substantially reduced the
and continuing the use of the cuprous salt solu
10
foaming properties of- the solution, and that when
tion
in the said separation or diolefins.
the filter was by-passed the solution increased
2. The improvement in the separation of ole?ns
greatly in foaming properties. The variation in
according to claim 1 in which the solid material
foaming characteristics with the use of a Magne
used
is a silicate of a met-a1 of groups II and III.
s01 precoated ?lter is indicated in the following
15, 3. The improvement in the separation of ole?ns
according to claim 1 in which the solid material
table:
Foam test at 32° F.
3'
,
is a magnesium silicate.
4. The improvement in the separation of ole?ns
according to claim 1 in ‘which the solid material
Cc. foam X breaking-time in sec.
Filter prccoat
Hour
—————-W-——"
380 gins. Magncsol.___
195
240
262
285
76
6B
60
60
305
329
30
32
380 gms. Filter Cel.
changed each 8 hrs._
5. The improvement in the separation of ole?ns
according to claim 1 in which the solid material is
of diatomaceous earth.
6. The improvement in the separation oi’ di
25 ole?ns from a mixture of hydrocarbons which
Filter by-passcd from
hour 329 ___________ ..
358
60
375
140
20 is an activated carbon.
comprises contacting the diole?ns with an aque
ous solution of 2-5 mols o! cuprous copper, 101/2
’ to 12 mols of ammonia and 4.mols of acetic acid, 7
EXAMPLE V
separating the aqueous solution of cuprous salt
The effect of varying the amount of Magnesol 30 from unabsorbed hydrocarbon mixture, heating
the separated aqueous cuprous salt solution to re
in batch treatments on the foaming properties of
cover diole?ns and form polymers of acetylenes,
a used cuprous ammonium acetate solution, such
treating the aqueous cuprous salt solution with
as that described in the above examples when no
a ?nely divided insoluble solid adsorptive ma
?lter was used in the plant, is shown in the fol
35 terial, separating the ?nely divided insoluble ad
lowing table:
sorptive material from the aqueous solution of
cuprous salt and recycling the aqueous solution
of cuprous salt to absorb more diole?ns.
7.. The improvements in the separation of di
40 olefins according to claim 6 in which the finely di
vided insoluble solid adsorptive material is a
magnesium silicate.
8. The improvement in the separation of di
ole?ns from a mixture of hydrocarbons which
Other additives, used in proportions of 3.6 gms./ 45 comprises contacting the diole?ns with an aque
ous solution of 2-5 mols of cuprous copper, 101/2
to 12 mols of ammonia and 4 mols of acetic acid,
separating the aqueous solution of cuprous salt
from
unabsorbed hydrocarbon mixture, heating
‘
Cc. loam X break time in sec.
Tggsllp" 122311’ WW 60 the separated aqueous cuprous salt solution to re
cover diole?ns and form polymers of acetylenes,
?ltering the aqueous cuprous salt solution through
88
600+
144+
.
a ?lter coated with a ?nely divided insoluble solid
300 cc. of the same used copper solution, gave
the following results:
_ ,
Additive ‘
Blank __________ ._
Johns Manville
"Sorbo A1”____
Dicalite “speed
?ow" ......... __
"-4200" ........ _ .
Johns
-
89
375
15
88
88
425
385
17
17
Manville
“Celite” ______ _ _
_
325
11
65
adsorptive material.
9. The improvement in the separation of di
ole?ns according to claim 8 in which the ?nely
divided insoluble solid adsorptive material is a
magnesium silicate.
The copper solution used in the above examples
_
10. The improvement in the separation of di
had the following approximate analysis:
60 ole?ns according to claim 6, in which the finely
divided insoluble adsorptive material is an acti
Mols per liter
vated
carbon.
Cuprous copper _______________________ _3.0
11. The improvement in the separation of di
Cupric copper _______________________ ____
0.3
ole?ns according to claim 8, in which'the ?nelyv
Acetate ______________________________ __
4.0
Ammonia ____________________________ _..
11.0
65 divided insoluble solid adsorptive material is an
activated carbon.
although it will be understood that this invention
12. The improvement in the separation of an
is not limited to the treatment of this solution but
ole?n from a mixture of hydrocarbons contain
is applicable with all cuprous solutions having
ing acetylenes using a cuprous salt solution as an
the capacity to extract ole?ns or dioleflns from 70 adsorption medium which comprises treating the
more saturated hydrocarbons.
mixture of hydrocarbons with the cuprous salt
We claim:
solution, separating the cuprous salt solution with
1. The improvement in the separation of ole?ns
acetylenes and an ole?n absorbed therein from
from mixtures of hydrocarbons using a cuprous
unabsorbed hydrocarbons of the mixture, desorb
salt solution as the absorption medium which 75 ing the absorbed ole?n for the separation. of the
4
2,899,882
7 ole?n and polymerizing the absorbed acetylenes
ole?n as described in claim 12, in which said sep
arated cuprous salt solution, from which the ab
sorbed ole?n is desorbed and in which the acetyl
enes are polymerized, undergoes the contacting
in' the cuprous salt solution separated from the
“unabsorbed hydrocarbons or the mixture, contact;
, ' ‘ing the thus-separated cuprous salt solution con
taining polymerized acetylenes with a solid ma
terial-having high adsorption capacity, separat
with, then the separating from, the solid material
ing the cuprous salt solution i'rom said solid ma
terial and continuing the use of the cuprous salt
solution as an absorption medium for separation
material is supported in lump form.
oi’ an ole?n.
13. The improvement in the separation of an
on circulating through a zone wherein the solid
10
CHARLES E. MORRELL.
JAMES K. SMALL.
JAMES H. MCATEER.
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