close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2131879

код для вставки
Patented Oct. 4, 1938‘
‘
2,131,879"
. UNITED STATES ‘PATENT OFFICE
2,131,879
nm'rnon or TREATING nrnaoosanon
ms'rmm'rss
Waldo can: and Carroll '5. Hochwalt, Dayton,
Ohio, assignors to Monsanto Chemical Com
pany, St. Louis, Mo., a corporation of Dela
ware
No Drawing. Application March 3, 1936,
Serial No. 66,893
3 Claims. ' (01. 196-36)
This invention relates to the re?ning of petro
on the one hand and cost of re?ning reagents
leum distillates for motor fuel purposes- which
and sacri?ce in yield on the other. Thus, for
example, a treatment with sulfuric acid may low
er the antiknock value of the fuel 5 to 15 points
if a substantially gum free and low sulfur prod
are rich in impuritiesthat impart color ,and odor,
or are productive of gum. In addition, the inven
5 tion contemplates a treatment whereby the anti
knock .value of the fuel is increased and the
susceptibility to tetra ethyl lead is improved.
The petroleum fractions which may be treated
according to the present invention are generally
10 made by cracking relatively higher boiling petro
leum products. However, they may ‘also be pro
duced by polymerizing lower boiling products. In
either case the raw material having the desired
boiling range for motor fuel purposes may be
7 15 malodorous, 011' color, rich in gum forming con;
stituents, ‘and'may frequently ‘contain sulfur in
objectionable amounts.
uct is desired. At the same time ten per cent
or more of the fuel may be lost as sludge.
The clay treatment avoids certain objection
able features of the sulfuric acid treatment, but
has no effect whatever on sulfur.
Furthermore, 10
the clay treatment does not eliminate the gum
forming constituents entirely, but rather elimi
nates only part of these to give temporary sta
bility and necessitates the use of so-called gum.
inhibitors in the finished gasoline product to 15
attain relatively permanent stability.
'
Whether one employs the clay or acid treat
Various methods are now used to refine this, ' ments, it is generally necessary, in order to obtain
so called, raw vgasoline to render it suitable for a gasoline product having the required color
20 motor fuel ‘purposes. In most instances several stability and freedom‘ from odor, to subject it to a 20
successive treatments are necessary in order that sweetening treatment. This treatment requires
a product having the desired properties is ulti ‘the use of additional chemical reagents and ne
‘ mately obtained. One common procedure for re
cessitates several additional steps in the re?ning
moving the sulfur and gum forming constituents
25 consists in washing the raw gasoline with sul
furic acid, subsequently with water, and there
after with alkali to remove residual acidity. The
product is then redistilled.
vAn alternative procedure consists in contact
‘30 ing the raw gasoline with active clay, whereby
the gum forming constituents are partially‘ sepa
rated. It is generally necessary to follow the clay
treatment with a doctor treatment, which is cal
culated to remove objectionable odors, especially
35 those attributable to the presence of sulfur im
purities; Not infrequently‘ this is also necessary
in the case of acid treated gasoline. With either
method of treatment gum inhibitors are com
monly added to the gasoline, especially if the
40 gasoline is apt to-be stored for. a considerable
period of time before use.
Present day practices share many objection
able features. Thus, for example, the sulfuric
acid treatment is not selective. In other words,
45 it not only combines with the gum forming con
stituents, but also with the desirable oleiinic
components of a raw gasoline, thereby reducing
the yield of gasoline and impairing the antiknock
quality of the product. A reduction in the
50 amount of sulfuric acid employed to reduce the
loss of desirable motor fuel. constituents is pos
sible only to a limited extent inasmuch as a
substantial amount of sulfuric acid is necessary,
especially where a reduction in the sulfur con
55 tent of the gasoline is desired. Because it is not
operation.
.
In the usual sweetening reaction, the mercap
tans are transformed quantitatively to disul?des.
This is usually accomplished with the aid of a
source of oxygen. The presence of smallquan
titles of disulfides contributes materially to poor
color stability. poor susceptibility to the effect of
tetra ethyl lead, poor susceptibility to gum inhibi- .
tors, and'to an actual loss in octane number. In
addition, the presence of‘ free sulfur, which is
normally required in excess to assure complete
conversion of the mercaptides to disuliides, im 35
pairs color stability and promotes corrosion. The
e?eot of oxygen on cracked gasolines is rather
well known, and the resulting peroxidation exerts
a detrimental effect on inhibitor susceptibility
and antiknock properties, (see “Oil and Gas J our 40
nal" {of February 6, 1936, page 28 et seq.) .
According to the present invention, the raw
gasoline is treated in a manner described more
fully hereinafter, whereby the ‘following advan
tages and improvements over the prior processes 45
are attained:
.
1. Practically complete and selective removal-of
gum forming constituents, without loss of
desirable gasoline constituents.
'
2. Saving in cost of gum inhibitors, by elimi
4. No-loss in the desired ole?n or aromatic con- '
stituents.
.
r
5. Substantial reduction of sulfur impurities.
_ ‘possible to improve gasoline with regard to the
6. Improved susceptibility to, and permanence
presence of sulfur and gum forming constituents
of tetra ethyl lead treatment. ,
without materially reducing the yield and anti- . '7. Improved color stability. , v
'
r
knock properties of the fuel, re?ners indulge in
l 60 a compromisebetween gum andsulfur impurities
50
nating the necessity therefor.
3. Improved antiknock properties.
8. Nearly total elimination of treating reagent
and processing operation costs.
55
2
2,181,879
9. Recovery of gum and sulfur components in
a non-corrosive utilizable form.
10. General applicability of re?ning ,method to
widely varying raw gasolines whereby a
product having a high induction period is
readily and conveniently obtained.
The polymerized products which are carried along
with the treated gasoline vapors and steam may
be removed in other ways, for example, by drying
the vapors as with calcium oxide, or other suitable
drying agents. In this way the water is removed
and the polymer may be separated from the gaso
nline vapors by suitably adjusting the temperature,
the polymer thereby condensing out because of
present invention, petroleum hydrocarbon vapors - its lower vapor pressure. Alternatively, the poly
According to one preferred embodiment of the
10 of the gasoline boiling range and steam are con- - mer can be removed from the steam containing 10
tacted with a solid catalyst surface or are scrubbed gasoline vapor stream by scrubbing the vapors
with a mobile liquid catalyst medium, the temper
ature, time of contact and activity of the catalyst
being so adjusted with respect to each other as to
15
convert practically all of the gum forming con
stituents and a substantial part of the sulfur im
purities into relatively high, boiling polymers. In
general, the preferred catalytic materials are non
reducible, substantially non-volatile, inorganic
20 acids, or acid reacting salts, or esters, which may
25
include activating substances, notably salts of
heavy metals. By means of the foregoing treat
ment the undesirable impurities are converted
into a form whereby they may be separated by
various physical means that do not necessitate the
use of chemical re?ning agents.
.
The following comparative analyses of a gaso
line before and after treatment are typical of the
results obtainable by practicing our invention:
with high boiling liquid media capable of holding
back the polymer, such for example, as phos
phoric acid, lubricating oil, molten para?ln, and
other scrubbing media having a solvent action or 15
a?‘inity' for the polymers formed in the catalytic
step of our re?ning process.
In our co-pending application ?led of even date,
we have shown that if a substantially water-free
gasoline vapor is treated with various catalytic
compositions, such as are described more fully
hereinafter, the step for removing the polymer is
unnecessary and a product having excellent gaso
line motor fuel properties is directly obtainable.
By way of illustration:
A commercial cracked gasoline was treated by
flash distilling the the raw gasoline at a rate of
200-300 c. c. per hour in such manner that
throughout the run, vapors of substantially uni
form composition were obtained which were at a
Original
Treated
temperature of approximately 175°-185° C. These
vapors were introduced through a quarter inch
Gum value (cu. dish) ______________ __
Sulfur content (per cent)_____
Bromineiunsaturation number“
_
Octane number
__________ _ _
or
_________ _ _
_
599
. 17
04. 3
2
.09
61. 2
Yellow
68
Water white
Approximate yield ................................ _.
98%
We are aware that it has been proposed hereto
40 fore to treat various hydrocarbons with mixtures
of phosphoric acid and sulfuric acid. However,
‘we have found that under the conditions of our
process in its preferred form sulfuric acid is rapid
ly decomposed. Furthermore, the various acids of
45 phosphorus have been considered ineffective in
and of themselves for the purpose or re?ning raw
tube into phosphoric acid of approximately 100%
concentration and allowed to bubble upwardly
through about 6 to 10 inches of the acid which
was maintained at approximately 170°-180° C. by
an oil bath that surrounded all except a small por
tion of the upper extremity of the catalyst con
taining vessel. Su?lcient re?ux was thus afforded
in relation to the temperature, acid concentration, 40
etc. to produce a clean separation of gum forming
constituents and, substantial separation of sulfur
containing constituents in the form of a relatively
high boiling polymer, which polymer was all re
tained in the catalyst containing vessel and in in
timate admixture with the catalyst. This inti
mate mixture of polymer and catalyst was found
to be at least as good a scrubbing mediumfor the
gasoline (U. S. P. 1,914,953), and to the best of our
knowledge the use of these acids has met with no
commercial success in this ?eld. We are also
50 aware that it has been proposed heretofore to pass
hydrocarbon vapors in admixture with steam over
purpose of our invention as the acid itself.
a carrier sprayed with phosphoric acid. However,
such a process is not e?ectlve, or only partially ef
fective, at best and is supplemented by a chemical
55 consuming re?ning step, such for example, as a
were the characteristics of the original and the
Following condensation of the scrubbed vapors, 50
a light aqueous alkali wash was used to remove
the traces of hydrogen sul?de.
treated gasoline:
hypochlorite treatment (U._S. P._1,709,315).
We have found that the presence of steam does
not necessarily prevent the complete removal of
the undesirable impurities, particularly the gum
60 forming constituents, and that by proceeding as
hereinafter more fully‘set forth, it is entirely pos
sible to obtain all of the advantages of the inven
tion as enumerated hereinabove, without resort
ing to such supplementary chemical re?ning
We have discovered that even in the pres:
65
ence of steam the conversion of the objectionable
' steps.
constituents to higher boiling products is com
plete, but because of the presence of steam, these
higher boiling polymerized products are carried
70 over with the gasoline vapor, and when the gaso
line vapor has condensed, reappear in the liquid
product. Further, we have found that if the water
is removed from the condensate as by decantation
and the gasoline is redistilled in the absence of the
75. steam, a product of excellent quality is obtained.
The following
Original
Treated
Gum value, milligrams per 100 c. e. (cop
per dish) ______________________________ ._
332
Sulfur content, percent (lamp method) ...-.
0. 16
.
0. 07
5
63. 9
61
61. 2
63
Bromine unsaturation number (bromide
bromate reagent) ...................... . .
Octane number _______________________ .'
cid (unsaturated
___________________ .;..___.I.__.._
27.8
27.1
or ........ -1 ......................... ..
'Yellow
Water white
Approximate yield ................................ ..
99%
The oily polymer was formed in the phosphoric
acid to the extent of about 1% of the weight of
the gasoline treated. This polymer upon sub
sequent distillation at atmospheric pressure pos
sessed a boiling range of 240°-330° C.; only a
small undistilled'residue remained. During oper- '
ation of the process the polymer was disseminated
throughout the acid in the form of tiny globules
by the ?ow of gasoline vapors through the liquid
60
65
3
mixture. Upon stopping the‘ flow oi.’ vapors
through the catalyst the liquid polymer rose
rapidly to the surface of the acid and was there
upon separated from the acid by decantation in a
substantially acid free condition. The acid layer
was thus recovered practically quantitatively and
in excellent condition for repeated use.
The present invention contemplates the adap
tation of the process of our co-pending applica
10 tion to a gasoline vapor mixture which contains
steam. As indicated above, when such a. vapor
mixture is subjected to the action of our catalysts
a gum free ‘condensate is not obtained‘ directly.v
The following examples are illustrative of our
15 invention when steam or water are present in the
treating system:
'
Example I
tration and allowed to bubble upwardly through
about 6 to 10 inches of the acid which was main
tained at approximately 170°-180° C. by an oil
bath that surrounded all except a small portion
of the upper extremity of the catalyst containing
vessel.
The'resulting gasoline vapors were conducted
through a lagged tube ‘2 inches in diameter and
1 _foot long, packed with granular lime (CaO).
After contacting these vapors with the lime they 10
' were led to a condenser. The condensed gasoline
was of a bright, water white appearance and had
characteristics similar to those given in Ex
ample I.
v
‘
Example III
15
The procedure in this embodiment was the same
as in Example 11 with the exception that instead
A commercial cracked gasoline was treated by ‘ of passing the vapors over lime, they were intro
?ash distilling the raw gasoline at a rate of duced into a bath of molten para?ln which was,
200-300 c. e. per hour ‘in suchhmanner that
throughout the run, vaporsof substantially uni
form composition were obtained which were at a
temperature of approximately 17,5°-185° C. These
vapors were introduced througha quarter inch
tube into phosphoric acid of approximately 75%
concentration and allowed to bubble upwardly
through about 6 to 10 inches of the acid which:
was maintained at approximately l70°-_~1_i_i0° C. by
an oil bath that surrounded all except, a. small
portion of the upper extremity of' the catalyst
containing vessel.
The discharged gasoline vapors contain water...
which had its source in the dilute acid being used
as a catalyst. Following condensation, the water
was allowed to settle, the clear supernatant gaso-__
line layer was decanted. After a mild aqueous
alkaline wash to_ removeany hydrogen sul?de
present it was found upon examination to con
tain
However,
102 mg.itof
was
gum.
found that a simple
, redistilla~
tion of this decanted gum containing gasoline,
‘(using no special precautions to obtain fractiona
tion) resulted in a satisfactory product having a
45 gum content of only 4 mg. The followingxwere
the characteristics of the original and ?nal gaso
line product, the latter being separated from the
water and subsequently redistilled as described:
0mm‘
Gum value (cu. dish)
.
_._
Treated
and
‘redistilled
384
4‘
_
0. l6
0. l2
Bromine numbcnr..Oxygen bomb stability __________________ __
63. 2
1 hour
57. 4
‘4.5 hours’
Sulfur perwnt ___________ __
'These results show that although under cer
tain conditions the gasoline obtained isnot free
of gum, nevertheless, the ‘gum forming constitu
ehts are converted into such form as to be readily
‘separable from the gasoline by physical means,
as for example, simple distillation.
_ Example 11
A commercial cracked gasoline was'treatedby
?ash distilling the raw gasoliiie at a rate .of
200-300 0. c. per hourin such a manner that
throughout the run vaporsoi substantially uni;
temperature ofapproximately l'_l5°-l8,5° C. Along
form composition were'obtained which were ata
‘a with the gasoline vapors steam was introduced"
in a quantity equivalent to about 2 or 3' per
cent of the gasoline being treated. These vapors
‘were introduced through‘ a quarter inch tube into
kept at. the desired temperature by partially im
mersing the vessel containing the para-?in in a
heated. oil. bath.,The vapors issuing from the
para?in were led toga condenser and after con
densation anda mild alkali wash were found to
have the same general desirable characteristics 25
as the product of Example 1.
Example IV
Substitute 100 per cent phosphoric acid and 30
otherwise proceed as in Example 2. Equilibrium
acid condensation ‘conditions are soon established
and the product obtained after a period of 2 or
3 hours will be found to be substantially identical
with that obtained according to Example II.
85
Example V
To illustratelthe' application of the principles
orour invention ~to a. process in which the gaso
line is'in vapor state and the catalyst is solid 40
rather" than ?uid or mobile, as ‘in the case of the -
preceding examples, the gasoline vapor-steam
mixture, as described in Example II, was passed
through a tube or tower filled with granules of
pumice stone which were saturated with phos 45
phoric acid. The temperature of the tower was
preferably adjusted at 200-215° C. to prevent
substantial condensation of the polymer. The
tower consisted of a2 inch glass tube 30 inches
Iong?agged and electrically heated to maintain 50
the ‘desired temperature condition. Some con
dehsation was perceptible but ‘it did not inter
fere with the successful ‘working of the process.
_ In lieu‘ 'oi'lthe pumice granules there were sub
stituted granular pellets of clay made by mixing 55
clay with‘approximately 25 per cent by weight
of 85 per cent phosphoric acid and su?iclent
water to produce a'moldable, mix. The mix was
formed into‘ pellets and dried at‘ 105° C., after
which it was’p'acked in the tower.
60
Other carriers may be used, such for example
as. a moldable mixture of sodium ‘meta phosphate
and, phosphoric acid together with activated car
honor other adsorbi-z'nt;v forms of carbonaceous
materials capable of holding .the phosphoric
acid. Coal, coke, peat and cellulosic materials
may be ‘substituted for the activated carbon to
65
form a'soil carrier for the active component.
The vapors were introduced at the top of the
tower and caused'to ?ow downward through the 70
catalyst after which they were condensed and
worked up as in. Example 1,- Example 11 or Ex
ample III t0v obtaimthe?nished‘product.
_
While ,ortho' phosphoric vacid is admirably
75 phosphoric acid of approximately 85% conc'en- - suited for‘ the purpose of our process, in that it
75
4
2,131,879
not only effects substantially complete conversion
of the gum forming constituents into separable
form, but in addition attains the‘other desirable
objectives of the present invention, nevertheless
other catalytic compositions may be substituted
therefor.
Thus, for example, a mixture of the
pyro and ortho phosphoric acids may be em
ployed, or alternatively a mixture of the meta,
pyro and ortho phosphoric acids. In lieu of
10' phosphoric acids the corresponding phosphorous,
and hypophos‘phorous acids may be substituted
in whole or in part for the phosphoric acids. In
acid catalyst or one may incorporate a small
amount of oxide directly to the acid, in which
case the oxide probably combines ‘with the acid
to form the salt in situ. The effect of the addi
tion of the salts is to reduce the temperature of
the reaction or the required time of contact, and
to some extent in changing the nature of the
hydrocarbons being treated as to improve sub
stantially the antiknock value, while at the same
time eliminating gum forming constituents, sul- .
fur and the like. The amount of the catalyt
ically active metal or salt which is used may vary
the case of the acids of lower state of oxidation - from. the fraction of a per cent up to several
there is evidence that the materials react, at per cent.
least in part, to form the more stable phosphoric
It is to be understood‘that the manipulated '.
acid with attending formation of phosphine.
steps in the preparation of the catalyst pellets
In addition to the oxygen acids of phosphorus.
one may use the acid salts to replace the‘free
acid in whole or in part. Similarly one may
or fragments as well as the form and size there
of are within the knowledge and discretion of
20 substitute the alkyl or arylxacid esters, which
evidently likewise undergo some chemical change
in the course of their use, but as in the other
instances, the reaction products are themselves
catalytically active.
25.
those skilled in the art.
'
We have found that certain advantages are
obtained by effecting the reaction within a com
paratively narrow range of temperature which
depends to some extent on the nature of the gas
oline, although it is possible to gain many of the
'
While from the standpoint of availability, the
oxygen acids of phosphorus and their derivatives
are especially suitable, we may use other known
non-reducible acids of phosphorus, such, for
example, as the sulfur containing acids of phos
phorus or the sulfur and oxygen containing acids
of phosphorus, as for example, the thiophos
phoric acid HaPSOa, or dithiophosphoric acid.
The catalyst may be made in various ways, for
advantages of our invention over a comparative- ,
ly wide range of temperature. In general, the
temperature should be sufficiently high with re
spect to the time and vconditions of contact be
tween the vapor and the scrubbing medium, to
convert the gum forming constituents into a
physically separable form and preferably without
inducing substantial condensation of the gasolinev
vapors.
.example, one may use ordinary phosphoric acid
When proceeding according to Example II we
35 syrup of commerce, which is approximately 85
have found it necessary in redistilling the de- l
per cent H3P04. However, if desired, one may
canted‘ condensate to re?ux or dephlegmate the
use 100 per- cent H3PO4 by adding sufficient P205 vapors only slightly, if at all, in order to obtain
to the phosphoric acid syrup of commerce to a good and complete separation of the gum form
combine with the free water. An excess of P205 ing polymer from the desired re?ned gasoline
40 may be added to the phosphoric acid syrup over
vapors. In general, this separation is not diffi
and above that required to react with all of the cult and only a very small amount of fractiona
water to form 100 per cent H3PO4, in which case tion or dephlegmation is necessary to give a very
clean separation.
one obtains a mixture of the pyro and ortho
phosphoric acid, or depending upon the amount
The manner of contacting or scrubbing the
of P205 added, a mixture of all three of the phos
vapors of the gasoline with the scrubbing ?uid '
phoric acids. Instead of adding .PzOs to the , or catalyst pellets is not critical. In general, any
commercial phosphoric acid, one may add P203. known equipment for effecting contact between a
The composition of the starting catalytic mate
rial may be varied considerably inasmuch as it
undergoes some change with use in attaining an
equilibrium. This is particularly true with re
spect to the water content of the catalytic com
position.
-
4
While we prefer to use a catalytic composition
56 which is immiscible with the polymer, whereby
it may be separated from the accumulated poly
mer by strati?cation and decantation or drain
ing, it is to be understood that the catalyst can
be present as a solid, in which case it may be
suspended or dispersed in the polymer or some
other ?uid inert vehicle.
'
As indica d in Example V the various cata
lysts may consist of stationary solid fragments
saturated with or consisting in part of the cata
vapor and a liquid, may be used.
sist of a mixture of the acid and some condensed
immiscible polymer. Another method of effect
ing the scrubbing operation consists in spraying
the liquid catalytic composition through a tower
‘in countercurrent or parallel direction with re
spect to the gasoline vapors being treated. If
desired, such tower may be ?lled with a packing,
over which the liquid flows downwardly and is
then recirculated.
*
,
A further modification of the catalytic compo,
sition consists in the use of catalytically active
saltseither alone or in admixture with the free
acids which salts exert desirable'catalytic in?u
70 ences. Such effect is produced by the addition
of salts of catalytically active metals, such as
copper, nickel, cadmium, zinc, cobalt, chromium,
iron and other heavy metals.
For this purpose
one may add a small amount of a salt as for
' example a phosphate, of the metal to the ?uid
_
_
In an analogous manner when a solid catalyst
is employed the vapors are contacted with the
catalyst by using well known- expedients for ef
fecting e?icient contact between vapors and
solids.
lytic compositions.
A very con
'venient procedure consists in bubbling the vapors
through a pool of the catalyst, which‘may con
_
I
‘
'
To remove polymer from the liquid acid scrub
bingv medium, the scrubbing medium is with
drawn continuously or periodically, permitted to
stratify, whereby polymer. rises to the surface
and the acid settles to the bottom, after which
the acid is returned to the system and the polymer
is subjected to recracking or used for other pur
poses, preferably after washing with water to re
move water soluble constituents.
The gasoline condensate obtained after somb
2,181,879
bing the raw gasoline with the catalyticvscrub—
‘ bing medium usually contains a small amount of
‘dissolved hydrogen sul?de, which is probably
present in the original raw gasoline. This is re.
moved conveniently by contacting the vapors
with lime, or washing the condensed gasoline
with a small amount of water or an aqueous ai
kaline solution of soda ash or alkali. This treat
ment to remove hydrogen sul?de does not in any
10 way change the motor fuel value of the conden
sate, but serves the function of reducing the odor
and corrosion tendency of the gasoline product.
After the alkali wash a water white gasoline is
5
ortho phosphoric acid is probably converted to
pyro phosphoric “acid and perhaps to meta phos
phoric acid. If desired one can add sufficient
P205 to retain a
on thereof in unreacted
form. As a rule there ‘is su?icient water in the
gasoline to combine with such P205 especially after
a long" period of treatment, even though the
amount of water dissolved in a decanted raw
gasoline is very small. One of the advantages of
the present invention resides in the fact that the l0
reacted P205 product is itself an excellent catalyst
for the purpose of our invention.
‘
Although we have described the principles of
obtained which has all of the properties described 1 our invention and have set forth speci?c embodi
15 heretofore.
.
ments of the application thereof, it is to be under 15
By using slightly higher temperatures or in
stood that these are illustrative only and that the
creasing the amount of steam or both, no polymer invention is not restricted to the temperatures,
separates on the solid catalyst.
concentrations, rates of ?ow, etc., speci?cally set
In this sepcification we referred to the unde
20 sirable constituents of the gasoline, which are forth. Further,’ it is to be understood that our
process may be operated continuously or other 20
separated by our process, asf‘gum forming con
wise, and at sub-atmospheric pressure as well as
stituents”, and in the catalyz'edpform these con
superatmospheric pressure, if so desired.
stituents have been referred to sometimes as
“polymers". Whilewe believe that the material
25 separated, is in fact the gum producing fraction
of the raw gasoline in the form of a polymer that
' includes sulfur impurities'of the raw gasoline,
probably in the form of a reaction product of,
some sort or other, it is to be understoodthat our
30 invention is not limited by any theory to explain
' the effects. Similarly, while we refer to the proc
ess as a catalytic process (in view of the fact
that there appears to be no perceptible con
'
35
sumption in the acid reacting phosphorus re
agent), it is to be understood that we ‘are not,
‘ in a position at this time to ‘classify the nature
of the reactions which contribute to the suc
cess of our process.
‘
Under the preferred conditions of operation
40 the Engler distillation characteristics of the raw
gasoline are not changed substantially. Never
theless, in view of the relatively wide range of
temperature condition which can be used with
out departing from the scope of our invention,
45 as well as the fact that chemical changes ad
ditional to those incident to gum removal may
take place, especially as the reaction tempera
What we claim is: .
1. In the catalytic re?ning of hydrocarbon
vapors of gasoline motor fuel boiling range by, 25
contact with a catalyst comprising an acid react
ing compound of phosphorus below cracking tem- .
perature in the presence of water vapor to convert
gum forming constituents of the said hydrocarbon
vapor to relatively high boiling products as com 30
pared to the gasoline being treated and separating
the desired gasoline product from the converted
gum forming constituents, the steps that com
prise removing water from the treated hydrocar
bon material as discharged from the catalyst and 35
subsequently separating gasoline from converted
gum forming constituents by fractionation.
2. In‘ the catalytic re?ning of hydrocarbon
vapors of gasoline motor fuel boiling range by
contact with a catalyst comprising an acid react
ing compound of phosphorus below cracking tem 40
perature in the presence of water vapor to convert
gum forming constituents of the said hydrocarbon
vapor to relatively high boiling products as com
pared to the gasoline being treated and separat
ing the desired gasoline product from the con
verted gum forming constituents, the steps that
ture approaches cracking temperatures, we do 'comprise passing the said vapors as discharged
not limit ourselves to a product whose'Engler from the catalyst in contact with a substance
50 distilling characteristics are exactly reproduced in ' having an a?inity for water and subsequently sep- .
the ?nal product.
' .
arating gasoline from converted gum forming con
In general, we prefer to operate-below cracking stituents by fractional condensation.
temperatures, that is, temperatures such as are
3. In the catalytic re?ning of hydrocarbon
commonly used in the art today in converting vapors of gasoline motor, fuel boiling range by
55 relatively high boiling hydrocarbons to those of contact with a catalyst comprising an acid react
' gasoline boiling range. One of the distinct ad
ing compound of phosphorus below cracking tem 55
vantages of our process resides in the fact that perature in the presence of water vapor to con
widely varying raw, cracked gasoline distillates vert gum forming constituents of the said hydro
may be treated without necessitating extensive carbon vapor to relatively’ high boiling products
changes in the treating conditions, ‘such as tem
as compared'to the gasoline being treated and 60
' perature, time of contact, etc. Nevertheless, under separating the desired gasoline product from the
some conditions successive treatments such as converted gum forming constituents, the steps
might be ha’tl by subjecting the gasoline to two that comprise condensing the said vapors as dis
catalytic operations in series or by recycling the charged from. the catalyst, decanting gasoline
containing converted gum forming constituents
65, stock in a batch-wise'manner, fall within the pur
' view of our invention.
from water, and separating the gasoline from 65
We have found it convenient in preparing the converted gum forming constituents by fractional
catalyst to dissolve or suspend P205111 phosphoric
acid of commerce which acid usually contains
70 about 15% water. By adding su?lcient P205 the
distillation.
I
WALDO C. AULT.
CARROLL A. HQCHWALT.
CERTIFICATE OF CORRECTI ON¢
Patent No. 2,131,879.
‘October 1;, 1958.
wALDo c'. AULT., ET AL.
It is hereby certified that error appears in the printed specification
of the above numbered patent'reqliiring correction as follows: Page 5, second
column, line 68, for the word "soil" read solid; page 5, first column, line
19,‘ for "sepcification"_ read specification; and that the" said'Letters Pat
ent should be read with‘this correction therein that the same may, conform
to the record of the ‘case, in ‘the Patent Office.
I
I‘
Signed and sealed this 15th day of November, A.- D. 1938.
_
(Seal)
Henry Van Arsd'ale
Acting Commissioner- of Patents.
Документ
Категория
Без категории
Просмотров
0
Размер файла
907 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа