U.S. patent application number 12/780452 was filed with the patent office on 2011-11-17 for method of feeding reactants in a process for the production of alkylate gasoline.
This patent application is currently assigned to Chevron U.S.A. Inc.. Invention is credited to Moinuddin Ahmed, Bong-Kyu Chang, Huping Luo, Krishniah Parimi.
Application Number | 20110282114 12/780452 |
Document ID | / |
Family ID | 44912326 |
Filed Date | 2011-11-17 |
United States Patent
Application |
20110282114 |
Kind Code |
A1 |
Luo; Huping ; et
al. |
November 17, 2011 |
METHOD OF FEEDING REACTANTS IN A PROCESS FOR THE PRODUCTION OF
ALKYLATE GASOLINE
Abstract
This application provides a process for the production of
alkylate blending components, comprising introducing a hydrocarbon
feed stream comprising an olefin to an orifice of a nozzle, at a
close distance from the orifice; and wherein the nozzle dispenses a
mixture of one or more recirculated streams and the hydrocarbon
feed stream through a throat of the nozzle to make alkylate
gasoline blending components. This application also provides a
process unit for the production of alkylate gasoline, comprising:
a) a nozzle having an orifice that dispenses one or more
recirculated streams comprising ionic liquid catalyst into a
chamber in the nozzle, b) a conduit for introducing a hydrocarbon
feed stream comprising an olefin to the orifice at a close distance
from the orifice; and c) a throat connecting the chamber in the
nozzle to an alkylation zone.
Inventors: |
Luo; Huping; (Richmond,
CA) ; Ahmed; Moinuddin; (Hercules, CA) ;
Parimi; Krishniah; (Alamo, CA) ; Chang; Bong-Kyu;
(Novato, CA) |
Assignee: |
Chevron U.S.A. Inc.
|
Family ID: |
44912326 |
Appl. No.: |
12/780452 |
Filed: |
May 14, 2010 |
Current U.S.
Class: |
585/14 ; 422/234;
585/717 |
Current CPC
Class: |
C07C 2/60 20130101; C10L
1/06 20130101; B01J 19/2465 20130101; C07C 2531/02 20130101; B01J
19/26 20130101; B01J 4/002 20130101; C07C 2/60 20130101; C10G
29/205 20130101; C10G 2300/305 20130101; C07C 9/16 20130101; C07C
2527/125 20130101; C10G 2300/1088 20130101; C10G 2400/02
20130101 |
Class at
Publication: |
585/14 ; 585/717;
422/234 |
International
Class: |
C10L 1/16 20060101
C10L001/16; B01J 8/00 20060101 B01J008/00; C07C 2/58 20060101
C07C002/58 |
Claims
1. A process for the production of alkylate gasoline blending
components, comprising introducing a hydrocarbon feed stream
comprising an olefin to an orifice of a nozzle, at a distance from
the orifice that is within 25 times a diameter of the orifice; and
wherein the nozzle dispenses a mixture of one or more recirculated
streams and the hydrocarbon feed stream through a throat of the
nozzle to make alkylate gasoline blending components.
2. The process of claim 1, wherein the hydrocarbon feed stream
additionally comprises an isoparaffin.
3. The process of claim 1, wherein the one or more recirculated
streams comprise an external recirculated stream and an internal
recirculated stream.
4. The process of claim 3, wherein the hydrocarbon feed stream is
introduced to a chamber of the nozzle housing a center piece from
which the external recirculated stream flows towards the
orifice.
5. The process of claim 1, wherein the distance from the orifice is
within 10 times the diameter of the orifice.
6. The process of claim 1, wherein the hydrocarbon feed stream is
introduced at an angle from 0 degrees to 90 degrees from a
direction of a flow of an external recirculated stream towards the
orifice.
7. The process of claim 6, wherein the angle is from 0 to 10
degrees.
8. The process of claim 6, wherein the angle is from 35 degrees to
75 degrees.
9. The process of claim 6, wherein the external recirculated stream
comprises regenerated catalyst.
10. The process of claim 1, wherein the hydrocarbon feed stream is
introduced through a dip tube into an external recirculated stream
in a center piece of the nozzle prior to dispensing the external
recirculated stream and the hydrocarbon feed stream through the
orifice.
11. The process of claim 1, wherein the introducing is done at a
single location.
12. The process of claim 1, wherein the introducing is done at
multiple locations.
13. The process of claim 1, wherein the hydrocarbon feed stream is
introduced at a location selected from the group of before the
orifice of the nozzle, in a chamber in the nozzle between the
orifice and the throat, in the throat of the nozzle, and
combinations thereof.
14. The process of claim 1, wherein the one or more recirculated
reactant streams come from an alkylation zone comprising an ionic
liquid catalyst.
15. The process of claim 1, wherein the mixture is dispensed into
an alkylation zone comprising an ionic liquid catalyst.
16. The process of claim 15, wherein a residence time of reactants
in the alkylation zone is less than 3 seconds.
17. The process of claim 1, wherein a linear velocity of the
hydrocarbon feed stream when it is introduced is high enough to
reduce a production of C11+ hydrocarbons.
18. The process of claim 15, wherein an alkylate gasoline blending
component having a RON greater than 90 is produced in the
alkylation zone.
19. The process of claim 15, wherein an alkylate gasoline blending
component comprising less than 6 wt % C11+ is produced in the
alkylation zone.
20. A process unit for the production of alkylate gasoline,
comprising: a) a nozzle having an orifice that dispenses one or
more recirculated streams comprising an ionic liquid catalyst into
a chamber in the nozzle, b) a conduit for introducing a hydrocarbon
feed stream comprising an olefin to the orifice at a distance from
the orifice that is within 25 times a diameter of the orifice; and
c) a throat connecting the chamber in the nozzle to an alkylation
zone where alkylate gasoline blending components are produced.
21. The process unit of claim 20, wherein the hydrocarbon feed
stream additionally comprises an isoparaffin.
22. The process unit of claim 20, wherein an alkylate gasoline
blending component comprising less than 6 wt % C11+ is produced in
the alkylation zone.
23. The process unit of claim 20, wherein the distance from the
orifice is within 10 times a diameter of the orifice.
24. The process unit of claim 20, wherein the one or more
recirculated streams comprise an external recirculated stream.
25. The process unit of claim 20, wherein a flow of the hydrocarbon
feed stream through the conduit is at an angle from 0 degrees to 90
degrees from a direction of flow of the one or more recirculated
streams towards the orifice.
26. The process unit of claim 20, additionally comprising an inlet
that feeds an internal recirculated stream from the alkylation zone
to the chamber of the nozzle.
Description
TECHNICAL FIELD
[0001] This application is directed to a method of feeding
reactants in a process for the production of alkylate gasoline
blending components and to a process unit for the production of
alkylate gasoline blending components.
SUMMARY
[0002] This application provides a process for the production of
alkylate blending components, comprising introducing a hydrocarbon
feed stream comprising an olefin to an orifice of a nozzle, at a
distance from the orifice that is within 25 times a diameter of the
orifice; and wherein the nozzle dispenses a mixture of one or more
recirculated streams and the hydrocarbon feed stream through a
throat of the nozzle to make alkylate gasoline blending
components.
[0003] This application also provides a process unit for the
production of alkylate gasoline, comprising:
[0004] a) a nozzle having an orifice that dispenses one or more
recirculated streams comprising ionic liquid catalyst into a
chamber in the nozzle,
[0005] b) a conduit for introducing a hydrocarbon feed stream
comprising an olefin to the orifice at a distance from the orifice
that is within 25 times a diameter of the orifice; and
[0006] c) a throat connecting the chamber in the nozzle to an
alkylation zone where alkylate gasoline blending components are
produced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an overview of a Venturi nozzle reactor.
[0008] FIG. 2a is a Venturi nozzle with multiple side inlets for
fresh hydrocarbon feed, where fresh hydrocarbon feed injects to the
internal chamber in the nozzle.
[0009] FIG. 2b is a Venturi nozzle with multiple side inlets for
fresh hydrocarbon feed, where fresh hydrocarbon feed injects to the
throat of the nozzle.
[0010] FIG. 3 is a Venturi nozzle with multiple side inlets
connecting to the reactor vessel feeding internal recirculated
streams to the nozzle, and multiple side inlets for fresh
hydrocarbon feed.
[0011] FIG. 4 is a Venturi nozzle with multiple center pieces
feeding external recirculated streams to the orifice in the nozzle
and multiple side inlets for fresh hydrocarbon feed.
[0012] FIG. 5 is a Venturi nozzle reactor with multiple Venturi
nozzles, each with their own internal recirculated stream.
[0013] FIG. 6A is a Venturi nozzle with the location of the
introduction of the four hydrocarbon feed streams in the chamber of
the nozzle, in between the orifice and the throat of the
nozzle.
[0014] FIG. 6B is a Venturi nozzle loop reactor where the
hydrocarbon feed stream (Q4) is introduced through a dip tube into
the center piece of the nozzle (rather than into the chamber or the
throat of the nozzle).
DETAILED DESCRIPTION
[0015] Examples of alkylation processes for the production of high
quality gasoline blending components are taught in U.S. Pat. Nos.
7,432,408, 7,432,409, 7,495,144, 7,553,999; and US Patent
Application Publications 2009/0171134, 2009/0171133, and
2009/0166257. The hydrocarbon feed stream comprises an olefin. In
some embodiment the hydrocarbon feed stream additionally comprises
an isoparaffin. Olefin means any unsaturated hydrocarbon compound
having at least one carbon-to-carbon double bond. Examples of
olefins are ethylene, propylene, butylene, and pentene. Isoparaffin
means any branched-chain saturated hydrocarbon compound. Examples
of isoparaffins include isobutane, isopentane, and mixtures
thereof. The olefins and isoparaffins can come from any source,
including varied refinery streams or from Fischer-Tropsch
processes. The hydrocarbon feed stream can comprise a mixture of
olefins, a mixture of isoparaffins, and combinations thereof.
[0016] The nozzle dispenses a mixture of one or more recirculated
streams and the hydrocarbon feed stream via an orifice through a
throat of the nozzle. The mixture comprises an isoparaffin, that is
supplied from either the hydrocarbon feed stream, the one or more
recirculated streams, or both. The orifice of the nozzle is
positioned towards one end of the nozzle, at the end from which the
nozzle dispenses the mixture of one or more recirculated streams
and the hydrocarbon feed stream. The orifice has a diameter that is
designed to provide optimal linear velocity and mixing of the
components of the mixture. The diameter of the orifice of the
nozzle is sized to match the volume of the mixture being
dispensed.
[0017] The one or more recirculated streams can comprise a
catalyst. The one or more recirculated streams can also comprise
un-reacted reactants, e.g. one or more isoparaffins. In one
embodiment the one or more recirculated streams are recirculated
from a reaction zone. An internal recirculated stream is one that
feeds directly from a reaction zone. An external recirculated
stream is one that feeds indirectly from the reaction zone. In one
embodiment, the one or more recirculated streams comprise an
external recirculated stream, an internal recirculated stream, and
mixtures thereof. In one embodiment, the hydrocarbon feed stream is
introduced to a chamber of the nozzle housing a center piece from
which the external recirculated stream flows towards the orifice.
This embodiment is illustrated in the figures. In one embodiment
the one or more recirculated streams come from an alkylation zone
comprising an ionic liquid catalyst. In another embodiment the
mixture of the recirculated streams and the hydrocarbon feed stream
are dispensed through a throat of the nozzle into an alkylation
zone comprising an ionic liquid catalyst.
[0018] In one embodiment the external recirculated stream comprises
regenerated acidic ionic liquid catalyst. The regenerated acidic
ionic liquid catalyst can comprise conjunct polymers at a lower
level than the amount of conjunct polymers in un-regenerated acidic
ionic liquid catalyst. Processes for regenerating acidic ionic
liquid catalysts are described in U.S. Pat. Nos. 7,666,811,
7,691,771, 7,651,970, 7,678,727, 7,674,739; and US Patent
Application Publication Numbers 2007/0142217, 2007/0142213,
2007/0142211, 2007/0142216, 2009/0253572, 2009/0163349,
2009/0170687, and 2009/0170688.
[0019] In one embodiment the hydrocarbon feed stream is introduced
at an angle from 0 degrees to 90 degrees from a direction of a flow
of the one or more recirculated streams towards the orifice. For
example the angle can be from 0 to 10 degrees, from 35 degrees to
75 degrees, or from about 45 degrees to about 65 degrees. The angle
can be selected to give the optimal mixing of the recirculated
streams and the hydrocarbon feed stream and to make the desired
quality alkylate gasoline blending components. One example is where
the hydrocarbon feed stream is introduced through a dip tube into
an external recirculated stream in a center piece of the nozzle
prior to dispensing the mixture of one or more recirculated streams
and the hydrocarbon feed stream through the throat of the nozzle.
One embodiment of this is illustrated in FIG. 6B.
[0020] In one embodiment the nozzle dispenses the mixture of the
recirculated streams and the hydrocarbon feed stream through the
throat of the nozzle into an alkylation zone comprising an ionic
liquid catalyst. An alkylation zone is a zone comprising at least
one isoparaffin and at least one olefin, in which the isoparaffin
and olefin are alkylated under alkylation conditions. Examples of
alkylation zones are reactors and reactor vessels. Alkylation
conditions are produced in the alkylation zone. For example, the
molar ratio between the olefin and the isoparaffin can be in the
range of 1 to 100, 2 to 50, 2 to 20, or 2 to 10. Catalyst volume in
the alkylation zone can be in the range of 2 vol % to 70 vol %, or
5 vol % to 50 vol %. The temperature in the alkylation zone can be
in the range of -20.degree. C. to 100.degree. C. The pressure in
the alkylation zone can be in the range of atmospheric pressure to
8000 kPa. Alternatively, the pressure can be any pressure
sufficient to keep the reactants in the mixture dispensed from the
nozzle in the liquid phase. The residence time of the reactants in
the alkylation zone can be in the range of 0.01 seconds to 60
minutes. In one embodiment the residence time of the reactants in
the alkylation zone is less than 3 seconds, less than 2 seconds,
from 0.05 to 1 second, or from 0.02 to 0.5 second. One advantage of
introducing the hydrocarbon feed stream close to the orifice of the
nozzle is that it shortens the residence time of the reactants in
the zone where there is insufficient mixing.
[0021] In one embodiment, the nozzle provides sufficient mixing and
excellent interfacial contact between the hydrocarbon feed stream
and the catalyst in the recirculated streams, such that the process
provides high quality gasoline blending components. In one
embodiment, the nozzle has dimensions compatible to the feed liquid
rates to obtain relatively a small droplet size of the catalyst to
maximizing interfacial surface area.
[0022] The hydrocarbon feed stream is introduced to the orifice of
the nozzle at a distance close to the orifice. The positioning of
the introduction location close to the orifice improves the
alkylate product selectivity. Generally, the distance is within 25
times the diameter of the orifice of the nozzle. In some
embodiments the distance maybe from zero to 25 times the diameter,
or zero to 10 times the diameter, or zero to 5 times the diameter,
or zero to 2 times the diameter. In one embodiment, the positioning
of the introduction location is directly adjacent to the
orifice.
[0023] One advantage to positioning the introduction location of
the hydrocarbon feed stream close to the orifice of the nozzle is
that it can reduce an undesired production of high boiling products
that comprise C11+ hydrocarbons. The production of C11+
hydrocarbons can be reduced to less than 10 wt %, less than 8 wt %,
less than 6 wt %, less than 4.8 wt %, less than 4.6 wt %, less than
4 wt %, or even less than 3.5 wt % C11+ hydrocarbons.
[0024] Another advantage to positioning the introduction location
of the hydrocarbon feed stream close to the orifice of the nozzle
is that it can improve the quality of the alkylate gasoline
blending components. In one embodiment, it increases the production
of C8 hydrocarbons, and gives an alkylate gasoline blending
component with a high RON. RON refers to Research-Method Octane
Number. The Research-Method Octane Number (RON) is determined using
ASTM D 2699-07a. In one embodiment the alkylate gasoline blending
component has a RON greater than 85, greater than 90, greater than
93.3, 94 or higher, greater than 95, or greater than 98. In some
embodiments the alkylate gasoline blend components have a low Reid
Vapor Pressure. The alkylate blend components can have a Reid Vapor
Pressure of 7.0 psi (4.827e+004 newtons/square meter) or less. In
one embodiment the gasoline blending components have a Reid Vapor
Pressure (RVP) less than 4.0 psi (2.758e+004 newtons/square meter).
In other embodiments the gasoline blending components have a RVP of
2.8 psi (1.931e+004 newtons/square meter) or less, or less than the
amount defined by the equation: RVP=-0.035.times.(50 vol % boiling
point, .degree. C.)+5.8, in psi. The chart of this equation is
shown in FIG. 1 in US Patent Publication Number US 20100025292.
[0025] The introducing of the hydrocarbon feed stream can be done
at a single location or at multiple locations. These different
embodiments are illustrated in the figures. The choice of number of
introducing locations can depend on the size of the nozzle and the
amount and effectiveness of mixing that is needed. The hydrocarbon
feed stream can be introduced in any location in the nozzle that is
close to the orifice. For example, the hydrocarbon feed stream can
be introduced at a location selected from the group of before the
orifice of the nozzle, in a chamber in the nozzle between the
orifice and the throat, in the throat of the nozzle, and
combinations thereof.
[0026] The catalyst is one that is useful for alkylation. In one
embodiment the catalyst is an acidic liquid catalyst. Examples of
acidic liquid catalysts are ionic liquid catalysts.
[0027] An acidic ionic liquid catalyst is composed of at least two
components which form a complex. The acidic ionic liquid catalyst
comprises a first component and a second component. The first
component of the acidic ionic liquid catalyst can comprise a Lewis
Acid selected from components such as Lewis Acidic compounds of
Group 13 metals, including aluminum halides, alkyl aluminum halide,
gallium halide, and alkyl gallium halide (see International Union
of Pure and Applied Chemistry (IUPAC), version3, October 2005, for
Group 13 metals of the periodic table). Other Lewis Acidic
compounds, in addition to those of Group 13 metals, can also be
used. In one embodiment the first component is aluminum halide or
alkyl aluminum halide. For example, aluminum trichloride can be the
first component of the acidic ionic liquid catalyst.
[0028] The second component making up the acidic ionic liquid
catalyst is an organic salt or mixture of salts. These salts can be
characterized by the general formula Q+A-, wherein Q+ is an
ammonium, phosphonium, boronium, iodonium, or sulfonium cation and
A- is a negatively charged ion such as Cl.sup.-, Br.sup.-,
ClO.sub.4.sup.-, NO.sub.3.sup.-, BF.sub.4.sup.-, BCl.sub.4.sup.-,
PF.sub.6.sup.-, SbF.sub.6.sup.-, AlCl.sub.4.sup.-, TaF.sub.6.sup.-,
CuCl.sub.2.sup.-, FeCl.sub.3.sup.-, HSO.sub.3.sup.-,
RSO.sub.3.sup.-, SO.sub.3CF.sub.3.sup.-, and 3-sulfurtrioxyphenyl.
In one embodiment the second component is selected from those
having quaternary ammonium halides containing one or more alkyl
moieties having from about 1 to about 12 carbon atoms, such as, for
example, trimethylamine hydrochloride, methyltributylammonium
halide, or substituted heterocyclic ammonium halide compounds, such
as hydrocarbyl substituted pyridinium halide compounds for example
1-butylpyridinium halide, benzylpyridinium halide, or hydrocarbyl
substituted imidazolium halides, such as for example,
1-ethyl-3-methyl-imidazolium chloride.
[0029] In one embodiment the acidic ionic liquid catalyst is
selected from the group consisting of hydrocarbyl substituted
pyridinium chloroaluminate, hydrocarbyl substituted imidazolium
chloroaluminate, quaternary amine chloroaluminate, trialkyl amine
hydrogen chloride chloroaluminate, alkyl pyridine hydrogen chloride
chloroaluminate, and mixtures thereof. For example, the acidic
ionic liquid catalyst can be an acidic haloaluminate ionic liquid,
such as an alkyl substituted pyridinium chloroaluminate or an alkyl
substituted imidazolium chloroaluminate of the general formulas A
and B, respectively.
##STR00001##
[0030] In the formulas A and B; R, R.sub.1, R.sub.2, and R.sub.3
are H, methyl, ethyl, propyl, butyl, pentyl or hexyl group, X is a
chloroaluminate. In the formulas A and B, R, R.sub.1, R.sub.2, and
R.sub.3 may or may not be the same. In one embodiment the acidic
ionic liquid catalyst is N-butylpyridinium chloroaluminate.
[0031] In another embodiment the acidic ionic liquid catalyst can
have the general formula RR'R''NH.sup.+Al.sub.2Cl.sub.7.sup.-,
wherein N is a nitrogen containing group, and wherein RR' and R''
are alkyl groups containing 1 to 12 carbons, and where RR' and R''
may or may not be the same.
[0032] The presence of the first component should give the acidic
ionic liquid a Lewis or Franklin acidic character. Generally, the
greater the mole ratio of the first component to the second
component, the greater is the acidity of the acidic ionic liquid
catalyst.
[0033] In one embodiment, the acidic ionic liquid catalyst is mixed
in either a reactor or in the nozzle with a hydrogen halide or an
organic halide. The hydrogen halide or organic halide can boost the
overall acidity and change the selectivity of the acidic ionic
liquid catalyst. The organic halide can be an alkyl halide. The
alkyl halides that can be used include alkyl bromides, alkyl
chlorides, alkyl iodides, and mixtures thereof. A variety of alkyl
halides can be used. Alkyl halide derivatives of the isoparaffins
or the olefins that comprise the feed streams in the alkylation
process are good choices. Such alkyl halides include, but are not
limited to, iospentyl halides, isobutyl halides, butyl halides,
propyl halides and ethyl halides. Other alkyl chlorides or halides
having from 1 to 8 carbon atoms can be also used. The alkyl halides
can be used alone or in combination. The use of alkyl halides to
promote hydrocarbon conversion by acidic ionic liquid catalysts is
taught in U.S. Pat. No. 7,495,144 and in U.S. patent application
Ser. No. 12/468,750, filed May 19, 2009.
[0034] It is believed that the alkyl halide decomposes under
hydroconversion conditions to liberate Bronsted acids or hydrogen
halides, such as hydrochloric acid (HCl) or hydrobromic acid (HBr).
These Bronsted acids or hydrogen halides promote the hydrocarbon
conversion reaction. In one embodiment the halide in the hydrogen
halide or alkyl halide is the same as a halide component of the
acidic ionic liquid catalyst. In one embodiment the alkyl halide is
an alkyl chloride, for example t-butyl chloride. A hydrogen
chloride or an alkyl chloride can be used advantageously, for
example, when the acidic ionic liquid catalyst is a
chloroaluminate.
[0035] The process unit for the production of alkylate gasoline
comprises a nozzle with a conduit for introducing the hydrocarbon
feed stream to an orifice in the nozzle at a distance from the
orifice that is close to the orifice. The orifice in the nozzle
dispenses one or more recirculated streams comprising ionic liquid
catalyst into a chamber in the nozzle. A throat connects the
chamber in the nozzle to an alkylation zone where alkylate gasoline
blending components are produced.
[0036] In one embodiment the process unit additionally comprises an
inlet that feeds an internal recirculated stream from the
alkylation zone to the chamber of the nozzle. This embodiment is
shown in the figures.
[0037] As described previously, the alkylate gasoline blending
components produced in the process unit can have a reduced level of
C11+ hydrocarbons. In one embodiment the flow of the hydrocarbon
feed stream through the conduit is at an angle, from a direction of
flow of the one or more recirculated streams toward the orifice,
that is selected to provide improved reaction conditions for making
alkylate gasoline blending components. For example, the flow of the
hydrocarbon feed stream through the conduit is at an angle from 0
degrees to 90 degrees from a direction of flow of the one or more
recirculated streams towards the orifice.
[0038] The following is a description of embodiments of the process
with reference to the figures:
[0039] FIG. 1. A fresh hydrocarbon feed stream (Q4) containing both
olefin and isoparaffin feeds was introduced into a nozzle loop
reactor at an angle of about 45.degree. from a direction of the
flow of a main recirculation stream (Q3) towards an orifice. The
fresh hydrocarbon feed stream was introduced in a chamber of the
nozzle housing a center piece of the nozzle from which a
recirculation stream, named external recirculation stream, (Q3)
flows in. Another recirculated reactant stream (Q2), named internal
recirculation stream, from an alkylation zone that is a reactor
vessel containing an ionic liquid catalyst is also fed via an inlet
on the side of the nozzle (2) to the chamber of the nozzle. The
orifice dispenses the external recirculation stream at high speed
into the chamber, where it mixes with the hydrocarbon feed stream
and the internal recirculation stream. A mixture (Q1) of the
external recirculation stream (Q3), the hydrocarbon feed stream
(Q4), and the internal recirculation stream (Q2) are dispensed
through a throat of the nozzle (1) into the alkylation reactor
vessel. Alkylate products are produced and eluted from the
alkylation reactor vessel.
[0040] FIG. 2A shows an embodiment of a Venturi nozzle loop reactor
where the fresh hydrocarbon feed (Q4) is introduced in four
locations on opposing sides of a nozzle loop reactor at an angle of
approximately 60.degree. from a direction of the flow of a
recirculated reactant stream (Q3) towards an orifice. The
hydrocarbon feed streams are introduced in a chamber of the nozzle
housing a center piece of the nozzle from which an external
recirculation stream flows in.
[0041] FIG. 2B is similar to FIG. 2A, with the location of the
introduction of the four hydrocarbon feed streams moved to the
throat of the nozzle. In this embodiment, the hydrocarbon feed
streams are introduced from the side of the throat and below the
center piece from which an external recirculation stream flows
in.
[0042] FIG. 3 is similar to FIG. 2A, with multiple side inlets
delivering recirculated reactant streams (Q2) into the nozzle.
[0043] FIG. 4 shows a Venturi nozzle loop reactor with multiple
center pieces to the nozzle each having an orifice dispensing an
external recirculation stream into a chamber in the nozzle. The
fresh hydrocarbon feeds (Q4) were introduced in multiple locations
into the nozzle loop reactor at an angle of approximately
50.degree. from the direction of the flows of the multiple external
recirculation streams (Q3) towards the orifices. As in the earlier
figures, a recirculated reactant stream (Q2) from an alkylation
zone that is an alkylation reactor vessel was also fed via an inlet
on the side of the nozzle to the chamber in the nozzle. The
orifices dispensed the external recirculation streams at high speed
into the chamber, where they mixed with the hydrocarbon feed
streams and the recirculated reactant stream. A mixture (Q1) of the
external recirculation streams (Q3), the hydrocarbon feed streams
(Q4), and the internal recirculation stream (Q2) were dispensed
through a throat of the nozzle (1) into the alkylation reactor
vessel.
[0044] FIG. 5 shows a process unit with multiple Venturi nozzles,
similar to those described in FIG. 1, dispensing into the same
alkylation zone. Each Venturi nozzle has its own recirculated
reactant stream coming from the same alkylation zone
[0045] FIG. 6A is similar to FIG. 2A, with the location of the
introduction of the four hydrocarbon feed streams still in the
chamber of the nozzle, but in between the orifice and the throat of
the nozzle. In this embodiment, the hydrocarbon feed streams are
introduced very close to the tip of the center piece where the
external recirculation stream is fed in.
[0046] FIG. 6B shows a Venturi nozzle loop reactor where the
hydrocarbon feed stream (Q4) is introduced through a dip tube into
the center piece of the nozzle (rather than into the chamber or the
throat of the nozzle) such that the hydrocarbon feed stream is
introduced close to the orifice of the nozzle. The hydrocarbon feed
stream is introduced at an angle of 0 degrees from the direction of
the flow of the external recirculation feed stream towards the
orifice. The other features of the process unit are as described in
FIG. 1.
[0047] The term "comprising" means including the elements or steps
that are identified following that term, but any such elements or
steps are not exhaustive, and an embodiment may include other
elements or steps. For the purposes of this specification and
appended claims, unless otherwise indicated, all numbers expressing
quantities, percentages or proportions, and other numerical values
used in the specification and claims, are to be understood as being
modified in all instances by the term "about." Furthermore, all
ranges disclosed herein are inclusive of the endpoints and are
independently combinable. Whenever a numerical range with a lower
limit and an upper limit are disclosed, any number falling within
the range is also specifically disclosed.
[0048] Any term, abbreviation or shorthand not defined is
understood to have the ordinary meaning used by a person skilled in
the art at the time the application is filed. The singular forms
"a," "an," and "the," include plural references unless expressly
and unequivocally limited to one instance.
[0049] All of the publications, patents and patent applications
cited in this application are herein incorporated by reference in
their entirety to the same extent as if the disclosure of each
individual publication, patent application or patent was
specifically and individually indicated to be incorporated by
reference in its entirety.
[0050] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to make and use the invention. Many
modifications of the exemplary embodiments of the invention
disclosed above will readily occur to those skilled in the art.
Accordingly, the invention is to be construed as including all
structure and methods that fall within the scope of the appended
claims. Unless otherwise specified, the recitation of a genus of
elements, materials or other components, from which an individual
component or mixture of components can be selected, is intended to
include all possible sub-generic combinations of the listed
components and mixtures thereof.
EXAMPLES
Example 1
[0051] A process unit was tested in a laboratory. The process unit
was a Venturi nozzle loop reactor configured as shown in FIG. 6B.
In one configuration of the process unit, the hydrocarbon feed
stream was introduced via a conduit into a nozzle through which an
external recirculation stream flows towards an orifice in the
nozzle. The two streams started mixing about 5 inches (12.7 cm)
away from the orifice of the nozzle. In a second configuration, the
hydrocarbon feed stream was introduced through a dip tube in the
conduit through which an external recirculation stream flowed
towards an orifice in the nozzle into the same nozzle loop reactor
operated at the same process conditions. The two streams start
mixing about 0.5 inch (1.27 cm) from the orifice of the nozzle. In
both configurations the hydrocarbon feed stream was introduced at
an angle of 0 degrees from the direction of the flow of the
external recirculation stream towards the orifice.
[0052] The external recirculated stream (Q3), the hydrocarbon feed
stream (Q4) comprised of olefin and isoparaffin, and an internal
recirculated stream (Q2) comprised of primarily isoparaffins from
an alkylation reactor and catalyst were fed into a chamber in the
nozzle. The mixture of the isoparaffin feed stream, the olefin feed
stream, and the recirculated reactant streams was dispensed into
the alkylation reactor through a throat of the nozzle.
[0053] The alkylation reactor comprised N-butylpyridinium
chloroaluminate (C.sub.5H.sub.5NC.sub.4H.sub.9Al.sub.2Cl.sub.7)
ionic liquid catalyst that had the following elemental
composition.
TABLE-US-00001 TABLE I Wt % Al 12.4 Wt % Cl 56.5 Wt % C 24.6 Wt % H
3.2 Wt % N 3.3
[0054] The alkylate product distributions from the alkylation
reactor from the process unit operated in the two configurations
are shown in Table II.
TABLE-US-00002 TABLE II Effect of Position of Olefin Feed Stream on
Alkylate Gasoline Properties Distance From Introduction of 12.7 cm
1.27 cm Hydrocarbon Feed Stream to Nozzle Orifice (5 inches) (0.5
inch) C5 (Wt %) 4-5 5 C6 (Wt %) 8-10 6 C7 (Wt %) 8-9 8 C8 (Wt %)
55-57 66.2 C9 (Wt %) 12-14 9.5 C10 (Wt %) 3-4 2.5 C11+ (Wt %) 6-8
3.2 TMP/C8 80-81 82 RON 94 94
[0055] By reducing the distance from the introduction of the
hydrocarbon feed stream to the nozzle orifice the selectivity to C8
was increased by about 10%. The amount of less valuable C11+ was
decreased substantially, by as much as 60%. The improvement in the
alkylate gasoline quality was done with no significant changes to
the process unit other than changing where the olefin feed stream
was introduced to the nozzle.
Example 2
[0056] A process unit having a Venturi nozzle was tested in a pilot
plant. The process unit had a 1/2'' feed pipe for the hydrocarbon
feed at an angle of 60.degree. from the direction of the flow of an
external recirculation stream towards the orifice. The hydrocarbon
feed was introduced to the Venturi nozzle through (1) the 1/2''
feed pipe and (2) a 1/4'' dip tube inserted in the pipe. The
effluent end of the dip tube was placed directly adjacent to the
nozzle orifice, within 1 times the diameter of the orifice. The
nozzle dispensed a mixture of external recirculated ionic liquid
catalyst, internal recirculated ionic liquid catalyst and unreacted
isoparaffin, and a fresh hydrocarbon feed stream comprising
isobutane and butene into an alkylation reactor. By feeding the
hydrocarbon feed stream through the dip tube the linear velocity of
the hydrocarbon feed through the conduit into the nozzle was
increased from 0.6 m/s to 7.7 m/s. The placement of the dip tube
significantly reduced the residence time of the hydrocarbon feed in
a zone of the Venturi nozzle with insufficient mixing. This reduced
the amount of C11+ products produced, and increased the RON of the
alkylate gasoline blending components produced by the alkylation
reactor.
* * * * *