U.S. patent application number 12/179542 was filed with the patent office on 2010-01-28 for process and apparatus for producing a reformate by introducing n-butane.
Invention is credited to Steven L. Krupa, Mark P. Lapinski, Clayton C. Sadler.
Application Number | 20100018900 12/179542 |
Document ID | / |
Family ID | 41567686 |
Filed Date | 2010-01-28 |
United States Patent
Application |
20100018900 |
Kind Code |
A1 |
Krupa; Steven L. ; et
al. |
January 28, 2010 |
PROCESS AND APPARATUS FOR PRODUCING A REFORMATE BY INTRODUCING
n-BUTANE
Abstract
One exemplary embodiment can be a process for producing a
reformate by combining a stream having an effective amount of
n-butane and a stream having an effective amount of naphtha for
reforming. Generally, the naphtha has not less than about 95%, by
weight, of one or more compounds having a boiling point of about
38--about 260.degree. C. as determined by ASTM D86-07. The process
can include introducing the combined stream to a reforming reaction
zone. Typically, the combined stream has an n-butane:naphtha mass
ratio of about 0.10:1.00--about 1.00:1.00.
Inventors: |
Krupa; Steven L.; (Fox River
Grove, IL) ; Lapinski; Mark P.; (Aurora, IL) ;
Sadler; Clayton C.; (Arlington Heights, IL) |
Correspondence
Address: |
HONEYWELL/UOP;PATENT SERVICES
101 COLUMBIA DRIVE, P O BOX 2245 MAIL STOP AB/2B
MORRISTOWN
NJ
07962
US
|
Family ID: |
41567686 |
Appl. No.: |
12/179542 |
Filed: |
July 24, 2008 |
Current U.S.
Class: |
208/133 ;
196/46 |
Current CPC
Class: |
C10G 35/04 20130101 |
Class at
Publication: |
208/133 ;
196/46 |
International
Class: |
C10G 35/02 20060101
C10G035/02 |
Claims
1. A process for producing a reformate by combining a stream
comprising an effective amount of n-butane and a stream comprising
an effective amount of naphtha for reforming, wherein the naphtha
has not less than about 95%, by weight, of one or more compounds
having a boiling point of about 38--about 260.degree. C. as
determined by ASTM D86-07, comprising: A) introducing the combined
stream to a reforming reaction zone wherein the combined stream has
an n-butane:naphtha mass ratio of about 0.10:1.00--about
1.00:1.00.
2. The process according to claim 1, wherein the combined stream
has an n-butane:naphtha mass ratio of about 0.20:1.00--about
0.50:1.00.
3. The process according to claim 1, wherein the reforming reaction
zone has a temperature of about 300--about 550.degree. C.
4. The process according to claim 1, wherein the reforming reaction
zone has a temperature of about 470--about 550.degree. C.
5. The process according to claim 1, wherein the reforming reaction
zone has a pressure of about 340--about 5,000 kPa and a liquid
hourly space velocity based on a naphtha feed of about 0.1--about
20 hr.sup.-1.
6. The process according to claim 1, wherein the reforming reaction
zone has a liquid hourly space velocity based on a naphtha feed of
about 0.5--about 5.0 hr.sup.-1.
7. The process according to claim 1, further comprising providing a
stream with an effective amount of hydrogen for reforming to the
reforming reaction zone.
8. The process according to claim 7, wherein the reforming reaction
zone has a pressure of about 340--about 5,000 kPa and a liquid
hourly space velocity based on a naphtha feed of about 0.1--about
20 hr.sup.-1, and the combined stream has an isopentane:naphtha
mass ratio of about 0.20:1.00--about 0.50:1.00.
9. The process according to claim 8, wherein the reforming reaction
zone has a temperature of about 470--about 550.degree. C.
10. A reforming apparatus for producing a reformate, comprising: 1)
a reforming reaction zone adapted to receive a stream rich in
n-butane and a stream rich in naphtha wherein the naphtha has not
less than about 95%, by weight, of one or more compounds having a
boiling point of about 38--about 260.degree. C. as determined by
ASTM D86-07; and 2) a first fractionation zone adapted to produce a
stream rich in at least one of methane and hydrogen, a stream rich
in C1-C4, and a stream rich in C5.sup.+.
11. The reforming apparatus according to claim 10, further
comprising: at least one fluid transfer zone adapted to receive the
stream rich in methane and/or hydrogen, which in turn comprises
hydrogen and at least a portion of the hydrogen is recycled to the
reforming reaction zone.
12. The reforming apparatus according to claim 10, further
comprising: a second fractionation zone adapted to receive the
stream rich in C1-C4 and produce at least one stream rich in C1-C3
and at least one stream rich in C4.
13. The reforming apparatus according to claim 12, wherein the
second fractionation zone further comprises: a first distillation
column; and a second distillation column; wherein the first
distillation column produces a first stream rich in C1-C2 and a
bottom stream, and the second distillation column is adapted to
receive the bottom stream and produce an overhead stream rich in
C3, a side-stream rich in isobutane, and a bottom stream rich in
n-butane.
14. The reforming apparatus according to claim 12, wherein the
reforming reaction zone is adapted to receive at least a portion of
the bottom stream of the second distillation column.
15. The reforming apparatus according to claim 13, wherein the
bottom stream is substantially n-butane.
16. A process for producing a reformate, comprising: A) combining a
stream substantially of n-butane and a stream substantially of
naphtha wherein the naphtha has not less than about 95%, by weight,
of one or more compounds having a boiling point of about 38--about
260.degree. C. as determined by ASTM D86-07, and introducing the
combined stream to a reforming reaction zone.
17. The process according to claim 16, wherein the combined stream
has an n-butane:naphtha mass ratio of about 0.10:1.00--about
1.00:1.00.
18. The process according to claim 16, wherein the combined stream
has an n-butane:naphtha mass ratio of about 0.20:1.00--about
0.50:1.00.
19. The process according to claim 16, wherein the reforming
reaction zone has a temperature of about 300--about 550.degree.
C.
20. The process according to claim 16, wherein the reforming
reaction zone has a pressure of about 340--about 5,000 kPa and a
liquid hourly space velocity based on a naphtha feed of about
0.1--about 20 hr.sup.-1.
Description
FIELD OF THE INVENTION
[0001] This invention generally relates to a process and an
apparatus for producing a reformate.
DESCRIPTION OF THE RELATED ART
[0002] In naphtha reforming, it is generally desired to decrease
the yield of C1-C5 products and increase the yield of aromatics.
Co-feeding a liquefied petroleum gas can reduce the C1-C5 product
yield and increase aromatics. However, such co-feeding has failed
to identify specific components that can reduce the yield of
aromatics and reduce the yield of undesirable products.
Particularly, certain components in the liquefied petroleum gas can
cause undesirable increases in undesirable reforming species. As a
consequence, it can be beneficial to provide a co-feed that can
increase aromatic yields while reducing both C5 paraffin yield and
C3 yield.
SUMMARY OF THE INVENTION
[0003] One exemplary embodiment can be a process for producing a
reformate by combining a stream having an effective amount of
n-butane and a stream having an effective amount of naphtha for
reforming. Generally, the naphtha has not less than about 95%, by
weight, of one or more compounds having a boiling point of about
38--about 260.degree. C. as determined by ASTM D86-07. The process
can include introducing the combined stream to a reforming reaction
zone. Typically, the combined stream has an n-butane:naphtha mass
ratio of about 0.10:1.00--about 1.00:100.
[0004] Another exemplary embodiment may be a reforming apparatus
for producing a reformate. The reforming apparatus can include a
reforming reaction zone and a first fractionation zone. Generally,
the reforming reaction zone is adapted to receive a stream rich in
n-butane and a stream rich in naphtha. Usually, the naphtha has not
less than about 95%, by weight, of one or more compounds having a
boiling point of about 38--about 260.degree. C. as determined by
ASTM D86-07. The first fractionation zone can be adapted to produce
a stream rich in at least one of methane and hydrogen, a stream
rich in C1-C4, and a stream rich in C5.
[0005] A further exemplary embodiment can be a process for
producing a reformate. The process can include combining a stream
substantially of n-butane and a stream substantially of naphtha,
and introducing the combined streams to a reforming reaction zone.
Typically, the naphtha has not less than about 95%, by weight, of
one or more compounds having a boiling point of about 38--about
260.degree. C. as determined by ASTM D86-07.
[0006] The embodiments disclosed herein can provide a reduction in
the production of C3, C4, and/or C5 and an increase in the total
aromatic yield by co-feeding n-butane. Thus, the vapor pressure of
a gasoline product may be lowered. In addition, co-feeding n-butane
may be more advantageous as compared to co-feeding other light
hydrocarbons.
DEFINITIONS
[0007] As used herein, the term "stream" can be a stream including
various hydrocarbon molecules, such as straight-chain, branched, or
cyclic alkanes, alkenes, alkadienes, and alkynes, and optionally
other substances, such as gases, e.g., hydrogen, or impurities,
such as heavy metals, and sulfur and nitrogen compounds. The stream
can also include aromatic and non-aromatic hydrocarbons. Moreover,
the hydrocarbon molecules may be abbreviated C1, C2, C3 . . . Cn
where "n" represents the number of carbon atoms in the one or more
hydrocarbon molecules. Also, methane can be abbreviated "C1",
isobutane can be abbreviated "iC4", normal butane can be
abbreviated "nC4", isopentane can be abbreviated "iC5", and normal
pentane can be abbreviated "nC5". Furthermore, a superscript "+" or
"-" may be used with an abbreviated one or more hydrocarbons
notation, e.g., C3.sup.+ or C3.sup.-, which is inclusive of the
abbreviated one or more hydrocarbons. As an example, the
abbreviation "C3.sup.+" means at least one hydrocarbon molecule of
three and/or more carbon atoms.
[0008] As used herein, the term "zone" can refer to an area
including one or more equipment items and/or one or more sub-zones.
Equipment items can include one or more reactors or reactor
vessels, heaters, exchangers, pipes, pumps, compressors, and
controllers. Additionally, an equipment item, such as a reactor,
dryer, or vessel, can further include one or more zones or
sub-zones.
[0009] As used herein, the term "rich" can mean an amount of
generally at least about 50%, and preferably about 70%, by mole, of
a compound or class of compounds in a stream.
[0010] As used herein, the term "substantially" can mean an amount
of generally at least about 80%, preferably about 90%, and
optimally about 99%, by mole, of a compound or class of compounds
in a stream.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic depiction of an exemplary reforming
apparatus.
[0012] FIG. 2 is a graphical depiction of total aromatic yield
versus C7 paraffin conversion for co-feeds methane and
n-butane.
[0013] FIG. 3 is a graphical depiction of total aromatic yield
versus C7 paraffin conversion for co-feeds methane and
isobutane.
[0014] FIG. 4 is a graphical depiction of iC5+nC5 and C5 olefin
yield versus C7 paraffin conversion for co-feeds methane and
n-butane.
[0015] FIG. 5 is a graphical depiction of iC5+nC5 and C5 olefin
yield versus C7 paraffin conversion for co-feeds methane and
isobutane.
[0016] FIG. 6 is a graphical depiction of iC4+nC4 and C3 yield
versus C7 paraffin conversion for co-feeds methane and
n-butane.
[0017] FIG. 7 is a graphical depiction of iC4+nC4 and C3 yield
versus C7 paraffin conversion for co-feeds methane and
isobutane.
DETAILED DESCRIPTION
[0018] Referring to FIG. 1, a reforming apparatus 100 can include a
reforming reaction zone 200, a separation zone 300, at least one
fluid transfer zone 400, a first fractionation zone 500, and a
second fractionation zone 600. The reforming reaction zone 200 can
be any suitable reforming reaction zone.
[0019] The reforming reaction zone 200 can receive a combined
stream 80. The combined stream 80 can include a stream 60 including
an effective amount of n-butane, a stream 70 including an effective
amount of naphtha, and a stream 350 including an effective amount
of hydrogen to facilitate the one or more reactions in the
reforming reaction zone 200. Preferably, the n-butane stream 60 can
be rich in or substantially n-butane, and the naphtha stream 70 can
be rich in or substantially naphtha. The naphtha can have not less
than about 95%, by weight, of one or more compounds having a
boiling point of about 38--about 260.degree. C., as determined by
ASTM D86-07. Generally, the stream 350 includes an effective amount
of hydrogen to facilitate the one or more reactions in the
reforming reaction zone 200. Preferably, the stream 350 is rich in
or substantially hydrogen. The hydrogen stream 350 can be recycled
back from the separation zone 300 and at least one fluid transfer
zone 400, as hereinafter described, to be combined with the
n-butane stream 60 and the naphtha stream 70.
[0020] Generally, the combined stream 80 has an n-butane:naphtha
mass ratio of about 0.10:1.00--about 1.00:1.00, preferably about
0.20:1.00--about 0.50:1.00. In addition, the combined stream 80 may
have a hydrogen:naphtha mole ratio of no more than about 10:1, and
preferably about 2:1--about 8:1. Afterwards, the combined stream 80
can enter the reforming reaction zone 200.
[0021] The reforming reaction zone 200 can include at least one
reforming reactor, preferably a plurality of reforming reactors
operating in serial and/or parallel. The reforming reaction zone
200 can operate under any suitable conditions and include any
suitable equipment. An exemplary reforming reaction zone 200 is
disclosed by Dachos et al., UOP Platforming Process, Chapter 4.1,
Handbook of Petroleum Refining Processes, editor Robert A. Meyers,
2nd edition, pp. 4.1-4.26 (1997). The reforming reaction can
dehydrogenate compounds such as naphthenes, can isomerize paraffins
and naphthenes, can dehydrocyclicize paraffins, and/or hydrocrack
and dealkylate paraffins. The reforming reaction zone 200 can
include other equipment such as furnaces and a combined feed heat
exchanger.
[0022] The one or more reforming reactors orientated in serial
and/or parallel flow can include any suitable reforming catalyst,
such as a catalyst including a group VIII metal, a group IV a
component, such as tin, and an inorganic oxide binder, such as
alumina, magnesia, zirconia, chromia, titania, boria, thoria,
phosphate, zinc oxide, silica, or a mixture thereof. Suitable
reforming reaction catalysts are disclosed in, for example, US
2006/0102520 A1.
[0023] Generally, the reforming reaction zone 200 can operate at a
temperature of about 300--about 550.degree. C., preferably about
470--about 550.degree. C., and more preferably about 500--about
550.degree. C. The reforming reaction zone 200 can operate at a
pressure of about 340--about 5,000 kPa, and a liquid hourly space
velocity (LSHV) of about 0.1--about 20 hr.sup.-1, preferably about
0.5--about 5.0 hr.sup.-1 based on the naphtha stream 70. The
reforming reaction zone 200 can produce a reforming reaction zone
effluent 210.
[0024] The separation zone 300 can receive the reforming reaction
zone effluent 210 from the reforming reaction zone 200 and provide
the stream 310 including hydrogen, preferably rich in or
substantially hydrogen, as well as a stream 320 including one or
more liquids, preferably rich in one or more liquids. The one or
more liquids stream 320 can be provided to the at least one fluid
transfer zone 400.
[0025] Usually, the at least one fluid transfer zone 400 includes
one or more separators or flash drums as well as one or more
compressors. In addition, the at least one fluid transfer zone 400
can include several heat exchangers to facilitate the separation of
gas and liquid products. Generally, the liquid from the separation
zone 300 can be passed through a series of vessels to further
separate the liquid from the gas. Usually, the gas includes
hydrogen that can either be recycled back in a stream 410 typically
rich in hydrogen after being combined with the stream 310 usually
rich in hydrogen to form the stream 350 typically rich in hydrogen
provided to the reforming reaction zone 200. A portion of the
hydrogen separated in the fluid transfer zone 400 can be removed as
a hydrogen product 420 to use, e.g., in other parts of a refinery
or a petrochemical complex. The separated liquid 430, which
typically contains C1.sup.1 and possibly other gases such as
hydrogen, can be provided to the first fractionation zone 500.
[0026] The first fractionation zone 500 can include a column 510,
such as a debutanizer, to separate the C4.sup.- from other
components in the one or more liquids stream 430. The first
fractionation zone 500 can provide a stream 540 rich in methane
and/or hydrogen, a stream 560 rich in C1-C4, and a stream 580 rich
in C5.sup.+ reformate. The column 510 can produce an overhead
stream 520 that generally includes components from the streams 540
and 560. Particularly, the overhead stream 520 from the column 510
can be cooled and routed to a reflux drum 530 where the, typically
vapor, stream 540 rich in methane and/or hydrogen can exit the
upper portion of the reflux drum 530, and the, usually liquid,
stream 560 rich in C1-C4 can exit the lower portion of the reflux
drum 530. The stream 540 rich in methane and/or hydrogen can be
routed to the at least one fluid transfer zone 400 where the
hydrogen can either be recycled back to the reforming reaction zone
200 in the stream 410, or removed as the hydrogen product 420, as
described above. The stream 580 rich in C5+ reformate can be taken
from the bottom of the column 510 and routed to the gasoline pool.
The stream 560 rich in C1-C4 can be routed to the second
fractionation zone 600.
[0027] The second fractionation zone 600 can receive this stream
560 rich in C1-C4 to produce at least one stream 680 rich in or
substantially C1-C3 and at least one stream 672 and/or 676 rich in
or substantially C4. Generally, although at least one stream 680
rich in C1-C3 is depicted as being a combination of two other
streams 630 and 664 hereinafter described, these streams 630 and
664 that make up the stream 680 may be provided separately to other
units within the refinery.
[0028] The second fractionation zone 600 can include a first
distillation column 620 and a second distillation column 660. The
first distillation column 620 can receive the stream 560 to produce
the first stream 630 including C1-C2, typically rich in C1-C2, as
an overhead stream 630 and a bottom stream 634 including C3-C4,
typically rich in C3-C4.
[0029] The second distillation column 660 can receive the bottom
stream 634 of the first distillation column 620 to produce the
overhead stream 664 having C3, typically rich in C3, and at least
one bottom stream 676 having C4, typically rich in C4. Optionally,
a side-stream 672 having isobutane, typically rich in isobutane,
may also be taken. Particularly, the second distillation column 660
can be designed to provide a product that is reduced in the
concentration of C3 and isobutane. As an example, the first
distillation column 620 can be a de-ethanizer followed by a C3/C4
splitter column 660. As such, the second distillation column 660
can provide the side-stream 672 rich in isobutane and a bottom
product 676 rich in n-butane and depleted in isobutane. Thus, the
second distillation column 660 in one exemplary embodiment is a
3-way splitter where C3 is produced as an overhead product. In one
preferred embodiment, the side-stream 672 includes 100%, by mole,
isobutane, and the bottom product 676 includes 100%, by mole,
n-butane. Optionally, the stream 676 can be recycled and at least a
portion can be combined as the n-butane stream 60 with the naphtha
stream 70. Alternatively, the split between isobutane and n-butane
may be less severe so that the bottom stream 676 can be rich in
n-butane and the side-stream 672 can be rich in isobutane. The
bottom stream 676 can provide n-butane, although the stream 676 may
contain some isobutane as a co-feed to the naphtha stream 70.
EXAMPLES
[0030] The following examples are intended to further illustrate
the disclosed embodiments. These illustrations of the embodiments
are not meant to limit the claims to the particular details of
these examples. These examples can be based on engineering
calculations and actual operating experience with similar
processes.
[0031] Tests are conducted by comparing a co-feed of methane (C1)
and naphtha, a co-feed of normal butane or n-butane (nC4) and
naphtha, and a co-feed of isobutane (iC4) and naphtha, which may be
referred to as a co-feed of, respectively, methane, n-butane, and
isobutane. Each test is conducted in a pilot plant using the same
reforming catalyst made in accordance with US 2006/0102520 A1. The
pilot plant is operated to minimize catalyst de-activation during
the test. The catalyst has a chloride content of about 1% by
weight. The feedstock is a commercial naphtha with an endpoint of
160.degree. C. The methane, n-butane, and isobutane are provided as
pure components. The feed contains 1.1 weight ppm sulfur on a
naphtha plus methane basis, or a naphtha plus n-butane or isobutane
basis for the respective methane, n-butane, or isobutane co-feed
tests. These conditions can provide a sulfur level at the reactor
inlet typical of a commercial unit reactor. The temperature of the
reactor is varied from 510-540.degree. C. to obtain performance
data at different conversion levels of the feedstock. The
parameters for the co-feed of methane, n-butane, and isobutane are
depicted below in Table 1:
TABLE-US-00001 TABLE 1 nC4 iC4 Parameter C1 Co-Feed Co-Feed Co-Feed
C1, nC4 or iC4 to Naphtha Mass 0.072 0.26 0.26 Ratio (gram/gram)
C1, nC4 or iC4 to Naphtha Mole 0.488 0.488 0.488 Ratio (mole/mole)
LHSV on Naphtha 2.75 2.75 2.75 (hr.sup.-1) LHSV on Naphtha + nC4 or
iC4 Not 3.67 3.71 (hr.sup.-1) Applicable Hydrogen:Hydrocarbon Mole
Ratio 8.0 8.0 8.0 Based on Naphtha (mole/mole) Hydrogen:(Naphtha +
nC4 or iC4) 8.0 5.4 5.4 Mole Ratio (mole/mole) Pressure (kPa) 446
446 446
[0032] The following formula is used to calculate the yield of,
respectively, methane, n-butane, isobutane, or hydrogen (each
"selected species" collectively abbreviated "ss") in the reactor
product:
Y.sub.ss=(P.sub.ss-L.sub.ss)/N*100% [0033] Y.sub.ss=net mass yield
of methane, n-butane, isobutane, or hydrogen based on a naphtha
feed; [0034] P.sub.ss=mass flow of methane, n-butane, isobutane, or
hydrogen in the reactor effluent; [0035] L.sub.ss=mass flow of
methane, n-butane, or isobutane co-feed, or the hydrogen feed; and
[0036] N=mass flow of a naphtha feed.
[0037] The following formula is used to calculate the yield of
species (i) in the reactor product, where (i) is a component other
than methane, isobutane, n-butane, or hydrogen in the reactor
effluent:
Y.sub.i=P.sub.i/N*100% [0038] Y.sub.i=net mass yield of species
based on a naphtha feed; [0039] P.sub.i=mass flow of species in the
reactor effluent; and [0040] N=mass flow of naphtha feed.
[0041] Referring to FIGS. 2-7, the yields of various compounds are
compared for the co-feeds of methane (C1), n-butane (nC4), and
isobutane (iC4) and are plotted versus C7 paraffin conversion. The
yields for the co-feeds n-butane and isobutane are calculated using
the same experimental computations and statistical methods, and are
compared against a baseline of feeding naphtha with a methane
co-feed. The methane co-feed test is used as a reference to ensure
that the same naphtha residence time in the reactor and the same
hydrogen partial pressure are used in both experiments. Use of the
methane co-feed in the reference experiment allows for these
process variables to be held constant while using methane with
minimal reactivity under reforming conditions. With these process
variables controlled, any yield differences can be attributed to
the effect of n-butane or isobutane on the reactions in the
reforming reaction zone. A line of best fit is drawn through some
of the data points.
[0042] Referring to FIGS. 2-3, comparisons are made of the yield of
total aromatics for a methane co-feed, an n-butane co-feed, and an
isobutane co-feed. As depicted, the n-butane co-feed provides a
higher aromatic yield than when co-feeding methane. In marked
contrast, referring to FIG. 3, an isobutane co-feed yields less
total aromatic yield as compared to the same methane co-feed
reference.
[0043] Referring to FIGS. 4-5, the sum of isopentane (iC5) and
n-pentane (nC5) (may be referred to collectively hereinafter as "C5
paraffins"), and C5 olefin yields for a methane co-feed, an
n-butane co-feed, and an isobutane co-feed are compared. As
depicted in FIG. 4, a co-feed of n-butane can yield substantially
the same amount of C5 paraffins and C5 olefin as a co-feed of
methane. However, as depicted in FIG. 5, a co-feed of isobutane can
yield higher amounts of C5 paraffins as compared to a co-feed of
methane. Particularly, the co-feeding of n-butane yields a lower
yield of C5 paraffins as compared to a co-feed isobutane whereas a
co-feed of isobutane yields higher amounts of undesirable C5
paraffins. Generally, it is preferred for a reformate product to
have less C5 paraffin compounds.
[0044] Referring to FIGS. 6-7, a propane plus propylene
(collectively may be abbreviated "C3") yield and iC4 plus nC4
(collectively may be referred to as "C4 paraffins") yield are
compared for a methane co-feed, an n-butane co-feed, and an
isobutane co-feed. Referring to FIG. 6, the n-butane co-feed yields
superior results with respect to C4 paraffins yield, namely a lower
yield as compared to co-feeding methane. In marked contrast,
referring to FIG. 7, the co-feed of isobutane demonstrates higher
yields of C3 and C4 paraffins as compared to the n-butane co-feed
in FIG. 6. Generally, it is preferred for a reformate product to
have less C3 and C4 paraffins.
[0045] As a consequence, the above testing demonstrates,
unexpectedly, the superiority of co-feeding n-butane as compared to
isobutane with respect to increasing aromatic content and reducing
the undesirable amounts of C3-C5, which are generally undesirable
in a reformate product used for, e.g., gasoline. Moreover, the
benefit of co-feeding n-butane can be particularly advantageous if
existing n-butane is available to provide to the reforming unit
without additional capital expense.
[0046] Without further elaboration, it is believed that one skilled
in the art can, using the preceding description, utilize the
present invention to its fullest extent. The preceding preferred
specific embodiments are, therefore, to be construed as merely
illustrative, and not limitative of the remainder of the disclosure
in any way whatsoever.
[0047] In the foregoing, all temperatures are set forth in degrees
Celsius, all parts and percentages are by weight, and all pressure
units are absolute, unless otherwise indicated.
[0048] From the foregoing description, one skilled in the art can
easily ascertain the essential characteristics of this invention
and, without departing from the spirit and scope thereof, can make
various changes and modifications of the invention to adapt it to
various usages and conditions.
* * * * *