U.S. patent application number 16/509431 was filed with the patent office on 2020-01-16 for methods of using ionic liquids as corrosion inhibitors.
The applicant listed for this patent is Baker Hughes, a GE company, LLC. Invention is credited to Mary Jane Felipe, Jerry Weers.
Application Number | 20200017766 16/509431 |
Document ID | / |
Family ID | 67874497 |
Filed Date | 2020-01-16 |
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United States Patent
Application |
20200017766 |
Kind Code |
A1 |
Weers; Jerry ; et
al. |
January 16, 2020 |
METHODS OF USING IONIC LIQUIDS AS CORROSION INHIBITORS
Abstract
Ionic liquid containing compositions may be used in the
production, recovery and refining of oil and gas. In addition, they
may be used to treat cooling water and/or to inhibit and/or prevent
corrosion of metals.
Inventors: |
Weers; Jerry; (Richmond,
TX) ; Felipe; Mary Jane; (Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Baker Hughes, a GE company, LLC |
Houston |
TX |
US |
|
|
Family ID: |
67874497 |
Appl. No.: |
16/509431 |
Filed: |
July 11, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62696544 |
Jul 11, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C23F 11/149 20130101;
C10G 2300/80 20130101; C10L 2200/0446 20130101; C10G 2300/304
20130101; C09K 15/20 20130101; C10G 33/04 20130101; C10L 10/04
20130101; C10L 2270/026 20130101; B01D 17/047 20130101; C10L
2200/0438 20130101; C10G 2300/1059 20130101; C10L 1/236 20130101;
C09K 8/58 20130101; C09K 8/524 20130101; C09K 15/30 20130101; C10G
2300/1055 20130101; C10G 2400/04 20130101; C09K 15/26 20130101;
C10G 31/08 20130101; C10L 10/16 20130101 |
International
Class: |
C09K 15/30 20060101
C09K015/30; C09K 15/26 20060101 C09K015/26; C09K 15/20 20060101
C09K015/20; C23F 11/14 20060101 C23F011/14 |
Claims
1. A method of inhibiting corrosion of a metallic surface in
contact with an acidic or aqueous fluid comprising contacting the
acidic or aqueous fluid with a corrosive inhibiting effective
amount of an ionic liquid of the formula: A.sup.+X.sup.- (I)
wherein A is or contains nitrogen, phosphorus or a heterocyclic
ring thereof; and X is an anion selected from the group consisting
of halides; hydroxyl; hydroxy containing nitrogen or sulfur
compounds; carbonates; alkyl carbonates; bicarbonates;
dithiocarbonates; trithiocarbonates; xanthates, thiocyanates;
alkoxides; carboxylates; hydroxycarboxylates; amino fatty acids;
anionic alkoxylated fatty acids; anionic metallic complexes, sulfur
or silicon containing anions; anionic phosphate esters, anionic
thiophosphate esters; anionic phosphonate esters; anionic
thiophosphonate esters; alkyl substituted phosphines; anionic urea;
anionic thiourea; anionic natural products; anionic thiols; anionic
phenols; anionic phenol resins; anionic copolymers of alpha olefins
and maleic anhydride, esters, amides, imides or derivatives
thereof; anionic acrylamido-methyl propane sulfonate/acrylic acid
copolymers; anionic polyacrylamide; anionic homopolymers,
copolymers and terpolymers of one or more acrylates, methacrylates
and acrylamides, optionally copolymerized with one or more
ethylenically unsaturated monomers; phosphated maleic copolymers;
an anionic homo or copolymer of an oxirane or methyloxirane and
mixtures thereof or a zwitterion.
2. A method of inhibiting corrosion of a metallic surface in
contact with an acidic or aqueous fluid comprising contacting the
acidic or aqueous fluid with a corrosive inhibiting effective
amount of an ionic liquid of the formula:
R.sup.1R.sup.2R.sup.3R.sup.4A.sup.+X.sup.- (II);
R.sup.1R.sup.2R.sup.3A.sup.+R.sup.8A.sup.+R.sup.5R.sup.6R.sup.7X.sup.-
(III) wherein: A in formula (II) is or contains nitrogen or
phosphorus or a heterocyclic ring thereof and wherein each A in
formula (III) is independently selected from nitrogen or phosphorus
or a heterocyclic ring thereof; and X is an anion selected from the
group consisting of halides; hydroxyl; hydroxy containing nitrogen
or sulfur compounds; carbonates; alkyl carbonates; bicarbonates;
carboxylates; hydroxycarboxylates; dithiocarbonates;
trithiocarbonates; xanthates, thiocyanates; alkoxides; anionic
urea; anionic alkyl substituted phosphines; anionic amino fatty
acids; anionic alkoxylated fatty acids; anionic acrylamido-methyl
propane sulfonate/acrylic acid copolymers; anionic phosphated
maleic copolymers; anionic homo or copolymers of an oxirane or
methyloxirane; anionic metal complexes; sulfur or silicon
containing anions; anionic phosphate esters; anionic thiophosphate
esters; anionic phosphonate esters; anionic thiophosphonate esters;
anionic thiols; anionic natural products; anionic phenols; anionic
phenol resins; anionic polyacrylamides; anionic copolymers of alpha
olefins and maleic anhydride, esters, amides, imides or derivatives
thereof; anionic alkyl substituted phosphines; and anionic
homopolymers, copolymers and terpolymers of one or more acrylates,
methacylates and acrylamides, optionally copolymerized with one or
more ethylenically unsaturated monomers; and mixtures thereof; and
further wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6 and R.sup.7 are independently selected from the group
consisting of hydrogen; benzyl; alkylbenzyl, or oxyalkyl; a
straight or branched alkyl group, an alkylbenzyl group, an
arylalkyl group, a straight or branched chain alkenyl group, a
hydroxyalkyl group or a hydroxyalkylbenzyl group; and a
polyoxyalkylene group; and R.sup.8 is a straight or branched
alkylene group, an alkylene oxyalkylene, or an alkylene
polyoxyalkylene or a zwitterion; and further wherein R groups may
be joined to form a heterocyclic nitrogen or phosphorus containing
ring.
3. The method claim 2, wherein A both occurrences of A in (III) are
or contain nitrogen and R.sup.1, R.sup.2, R.sup.3, R.sup.4,
R.sup.5, R.sup.6 and R.sup.7 are independently selected from the
group consisting of hydrogen; benzyl; oxyalkyl; a straight or
branched C.sub.1-30 alkyl group; a C.sub.7-30 alkylbenzyl group; a
C.sub.7-30 arylalkyl group; a straight or branched C.sub.3-30
alkenyl group; a C.sub.1-30 hydroxyalkyl group; a C.sub.7-30
hydroxyalkylbenzyl group; and a polyoxyalkylene group and further
wherein R groups may be joined to form a heterocyclic nitrogen or
phosphorus containing ring; and R.sup.8 is a straight or branched
C.sub.1-30 alkylene, an alkylene oxyalkylene, or an alkylene
polyoxyalkylene.
4. The method of claim 3, wherein R.sup.1, R.sup.2, R.sup.3,
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 of (II) and (III) are
independently selected from --H, a C.sub.1-20 alkyl,
--CH.sub.2CH.sub.2OH, and CH.sub.2CH(CH.sub.3)OH.
5. The method of claim 1, wherein X is a hydroxide, halide,
bicarbonate, carbonate, alkyl carbonate, alkoxide, carboxylate or a
hydroxycarboxylate.
6. The method of claim 3, wherein X is selected from the group
consisting of --Cl, --Br, --F or --I.
7. The method of claim 1, wherein X is selected from the group
consisting of anionic phosphate esters, anionic thiophosphate
esters, anionic phosphonate esters; anionic thiophosphonate esters;
anionic diphosphonic acids, 2-mercaptoethyl mercaptide, anionic
2-sulfanylethanol; anionic 2-sulfanyl, propan-1-ol; anionic
2-sulfanylbutan-2-ol; anionic 1-sulfanylbutanol-2-ol; and anionic
glucaric acid and mixtures thereof.
8. The method of claim 1, wherein A is selected from the group
consisting of an imidazolium or pyridinium.
9. The method of claim 8, wherein the pyridinium is an
alkylpyridinium.
10. The method of claim 8, wherein the ionic liquid is of the
structure: ##STR00013## wherein R is a C.sub.12-C.sub.18 alkyl or
alkenyl group and X is --OH, NH.sub.2 or C(.dbd.O)R.
11. The method of claim 7, wherein the ionic liquid is a phosphate
ester or thiophosphate ester of the structure (IIA) or (IIB):
##STR00014## wherein R is an alkyl or
RO(CH.sub.2CH.sub.2O).sub.nCH.sub.2CH.sub.2) and R'' and R''' are
independently selected from --H and a C.sub.1-C.sub.20 alkyl.
12. The method of claim 1, wherein the ionic liquid is a quaternary
ammonium halide.
13. The method of claim 12, wherein the quaternary ammonium halide
is of the structure: ##STR00015## wherein the alkyl group contains
from 1 to 20 carbon atoms.
14. The method of claim 1, wherein the ionic liquid is an alkyl
pyridine quat.
15. The method of claim 14, wherein the alkyl pyridine quat
contains more than one pyrindyl ring.
16. The method of claim 14, wherein the alkyl pyridine quat is of
the structure: ##STR00016## wherein R is a C.sub.1-C.sub.18 alkyl
or benzyl.
17. The method of claim 1, wherein X is selected from the group
consisting of anionic thiazoles, anionic triazoles and anionic
thiadiazoles.
18. The method of claim 1, wherein X is a carboxylate selected from
the group consisting of formate, acetate, propionate, benzoate,
n-butyrate, isobutyrate, pivalate, octanoate, laurate or is an
anion of a C.sub.18 fatty acid.
19. The method of claim 1, wherein X is a hydroxycarboxylate
selected from the group consisting of glycolate, lactate, citrate,
glucarate, gluconate and tartrate.
20. The method of claim 1, wherein the ionic liquid is present in a
treatment composition containing a second corrosion inhibitor and
further wherein the second corrosion inhibitor is not an ionic
liquid.
21. The method of claim 20, wherein the anion of the ionic liquid
is the same as the counter anion of the second corrosion
inhibitor.
22. The method of claim 1, wherein the acidic or aqueous liquid is
crude oil, petroleum fuel or oil, a condensate, a distillate or
cooling water.
Description
FIELD
[0001] The disclosure relates to the use of ionic liquids as
corrosion inhibitors.
BACKGROUND
[0002] Corrosion of metallic surfaces is often an acute problem
which arises during the production and refining of hydrocarbon
streams as well as in other industries which rely on aqueous fluids
for the removal of heat from one medium to another. For instance,
cooling towers extract waste heat to the atmosphere by cooling of a
water stream to a lower temperature. Cooling towers are used in oil
refineries, petrochemical and other chemical plants, thermal power
stations and power plants, steel mills, natural gas processing
plants, food processing plants, semi-conductor plants as well as
HVAC systems. Aqueous fluids, including those with high salt
content, cause corrosion which may lead to equipment failure
requiring equipment to be replaced. Corrosion also decreases plant
efficiency due to loss of heat transfer. This is often the result
of heat exchanger fouling caused by the accumulation of corrosion
products.
[0003] Highly corrosive conditions also arise during well
stimulation operations, such as pickling, acid washing, matrix
acidizing and acid fracturing where aqueous acidic solutions are
applied to the production zone to increase the size of pores within
the formation and to provide enlarged passageways for the flow of
hydrocarbons.
[0004] Corrosive aqueous fluids having high salt content are also
used in drilling and completion fluids. Marked corrosivity is often
seen when such brines are used as packer fluids since they remain
in contact with production tubing and casing for extended periods
of time.
[0005] Concerns of corrosion also arise in the treatment of gas
streams, such as carbon dioxide and hydrogen sulfide, which
generate highly acidic environments to which metallic surfaces
become exposed. For instance, corrosion effects from brine and
hydrogen sulfide are seen in flow lines during the processing of
gas streams. The presence of methanol, often added to such streams
to prevent the formation of undesirable hydrates, further often
increases the corrosion tendencies of metallic surfaces.
[0006] Further, naturally occurring and synthetic gases are often
conditioned by treatment with absorbing acidic gases, carbon
dioxide, hydrogen sulfide and hydrogen cyanide. Degradation of the
absorbent and acidic components as well as the generation of
by-products (from reaction of the acidic components with the
absorbent) results in corrosion of metallic surfaces.
[0007] Corrosion of metallic surfaces is evidenced by surface
pitting, embrittlement and loss of metal. Pitting occurs when
anodic and cathodic sites become stationary due to large
differences in surface conditions. Once a pit is formed, the
solution inside it is isolated from the environment and becomes
increasingly corrosive with time. The high corrosion rate in the
pit produces an excess of positively charged metal cations, which
attract chloride anions. In addition, hydrolysis produces hydrogen
ions. The increase in acidity and concentration within the pit
promotes even higher corrosion rates, and the process becomes
self-sustaining.
[0008] Various corrosion inhibitors for diminishing corrosive
effects on metal surfaces have been developed. Some corrosion
inhibitors can have serious consequences. For instance, sulfur
containing corrosion inhibitors may cause corrosion cracking which
translates into tubular failures. Such inhibitors further may
decompose at elevated bottomhole temperatures and release hydrogen
sulfide. The release of hydrogen sulfide as a decomposition product
likely induces sulfide stress corrosion cracking of the alloy
tubulars. Zinc based corrosion inhibitors have also been used
especially to address corrosive effects in cooling towers.
Unfortunately, zinc salts, oxides and sulfates often precipitate in
cooling water. In alkaline waters, particularly above about pH 7.5,
dissolved zinc tends to deposit or drop out. Thus, zinc salts are
known to be unstable in neutral or alkaline water. Scale formation
further typically results from the metals in inorganic corrosion
inhibitors. For instance, zinc scales typically form by use of zinc
containing corrosion inhibitors. The effectiveness of corrosion
inhibitors in aqueous systems thus significantly decreases.
[0009] Efforts have been undertaken to find more effective
corrosion inhibitors which do not render the negative effects of
those previously seen. For instance, alternative corrosion
inhibitors have been sought which are capable of controlling,
reducing or inhibiting corrosion without inducing sulfur-related
corrosion cracking of metallic alloy tubulars. Further, there
exists a need for improved compositions for inhibiting or
preventing corrosion in cooling water systems which are more
effective and are more environmentally acceptable compositions.
SUMMARY
[0010] In an embodiment, the disclosure relates to the use of
electronically neutral ionic liquids as corrosion inhibitors, the
ionic liquids represented by (I):
A.sup.+X.sup.- (I)
wherein A is or contains nitrogen, a nitrogen containing
heterocyclic ring, is or contains phosphorus, or a phosphorus
containing heterocycle; and X is an anion selected from the group
consisting of halides; hydroxyl; hydroxyl containing nitrogen or
sulfur compounds; sulfonates; sulfates; bisulfites; carbonates;
alkyl carbonates; bicarbonates; thiocarbonates; dithiocarbonates;
trithiocarbonates; xanthates, thiocyanates; alkoxides;
carboxylates; hydroxycarboxylates; amino fatty acids; anionic
alkoxylated fatty acids; anionic metallic complexes, sulfur or
silicon containing anions; sulfides; polysulfides; anionic
phosphate esters, anionic thiophosphate esters; anionic phosphonate
esters; anionic thiophosphonate esters; alkyl substituted
phosphines; anionic urea; anionic thiourea; anionic natural
products; anionic thiols; anionic phenols; anionic phenol resins;
anionic copolymers of alpha olefins and maleic anhydride, esters,
amides, imides or derivatives thereof; anionic acrylamido-methyl
propane sulfonate/acrylic acid copolymers; anionic homopolymers,
copolymers and terpolymers of one or more acrylates, methacrylates,
acrylamides and acids, optionally copolymerized with one or more
ethylenically unsaturated monomers; anionic phosphated maleic
copolymers; an anionic homo or copolymer of an oxirane or
methyloxirane and mixtures thereof or a zwitterion.
[0011] Another embodiment relates to the use of ionic liquids as
corrosion inhibitors, the ionic liquids represented by (II) and
(Ill):
R.sup.1R.sup.2R.sup.3R.sup.4A.sup.+X.sup.- (II);
R.sup.1R.sup.2R.sup.3A.sup.+R.sup.8A.sup.+R.sup.5R.sup.6R.sup.7X.sup.-
(III)
wherein:
[0012] A in formula (II) is or contains nitrogen or phosphorus or a
heterocyclic ring thereof and wherein each A in formula (III) is
independently selected from nitrogen or phosphorus or a
heterocyclic ring thereof; and
[0013] X is an anion selected from the group consisting of halides;
hydroxyl; hydroxy containing nitrogen or sulfur compounds;
carbonates; alkyl carbonates; bicarbonates; carboxylates;
hydroxycarboxylates; dithiocarbonates; trithiocarbonates;
xanthates, thiocyanates; alkoxides; anionic urea; anionic alkyl
substituted phosphines; anionic amino fatty acids; anionic
alkoxylated fatty acids; anionic acrylamido-methyl propane
sulfonate/acrylic acid copolymers; anionic phosphated maleic
copolymers; anionic homo or copolymers of an oxirane or
methyloxirane; anionic metal complexes; sulfur or silicon
containing anions; anionic phosphate esters; anionic thiophosphate
esters; anionic phosphonate esters; anionic thiophosphonate esters;
anionic thiols; anionic natural products; anionic phenols; anionic
phenol resins; anionic copolymers of alpha olefins and maleic
anhydride, esters, amides, imides or derivatives thereof; anionic
alkyl substituted phosphines; and anionic homopolymers, copolymers
and terpolymers of one or more acrylates, methacrylates and
acrylamides, optionally copolymerized with one or more
ethylenically unsaturated monomers; and mixtures thereof; and
further wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6 and R.sup.7 are independently selected from the group
consisting of hydrogen; benzyl; alkylbenzyl, or oxyalkyl (including
--CH.sub.2CH.sub.2OH) or --CH.sub.2CH(CH.sub.3)OH); a straight or
branched alkyl group, an alkylbenzyl group, an arylalkyl group, a
straight or branched chain alkenyl group, a hydroxyalkyl group or a
hydroxyalkylbenzyl group; and a polyoxyalkylene group; and R.sup.8
is a straight or branched alkylene group, an alkylene oxyalkylene,
or an alkylene polyoxyalkylene or a zwitterion; and further wherein
R groups may be joined to form a heterocyclic nitrogen, sulfur or
phosphorus containing ring.
[0014] In another embodiment, a method of enhancing the performance
of a corrosion inhibitor is provided by contacting the corrosion
inhibitor with a corrosion inhibiting ionic liquid. In these
instances, the corrosion inhibiting ionic liquid may act as an
intensifier for the corrosion inhibitor; the corrosion inhibitor
not being an ionic liquid.
DETAILED DESCRIPTION
[0015] The description provides specific details, such as material
types, compositions, and processing conditions in order to provide
a thorough description of embodiments of the disclosure.
Characteristics and advantages of this disclosure and additional
features and benefits will be readily apparent to those skilled in
the art upon consideration of the following detailed description of
exemplary embodiments. The description herein, being of exemplary
embodiments, is not intended to limit the scope of the claims.
[0016] As used herein and throughout various portions (and
headings) of this patent application, the terms "disclosure",
"present disclosure" and variations thereof are not intended to
mean every possible embodiment encompassed by this disclosure or
any particular embodiment(s). Thus, the subject matter of each such
reference should not be considered as necessary for, or part of,
every embodiment hereof or of any particular embodiment(s) merely
because of such reference.
[0017] Certain terms are used herein and in the appended
embodiments to refer to particular components. As one skilled in
the art will appreciate, different persons may refer to a component
by different names. This document does not intend to distinguish
between components that differ in name but not function. Also, the
terms "including" and "comprising" are used herein and in the
appended embodiments in an open-ended fashion, and thus should be
interpreted to mean "including, but not limited to . . . ."
Further, reference herein and in the appended embodiments to
components and aspects in a singular tense does not limit the
present disclosure or appended embodiments to only one such
component or aspect, but should be interpreted generally to mean
one or more, as may be suitable and desirable in each particular
instance. Thus, the use of the terms "a", "an", "the" the suffix
"(s)" and similar references are to be construed to cover both the
singular and the plural, unless otherwise indicated herein or
clearly contradicted by context.
[0018] All ranges disclosed herein are inclusive of the endpoints,
and the endpoints are independently combinable with each other.
Unless stated otherwise, any range of values within the endpoints
is encompassed. For example, where the endpoints of a range are
stated to be from 1 to 10, any range of values, such as from 2 to 6
or from 3 to 5 will be defined by the range.
[0019] All references are incorporated herein by reference.
[0020] The phrase "ionic liquid" refers to a neutral molten salt
composed entirely of ions and which is liquid at ambient or near
ambient temperatures. The phrase shall include the quaternary
organic salts of (I), (II) and (Ill). The ionic liquid functions as
a corrosion inhibitor.
[0021] The phrase "second corrosion inhibitor" shall refer to any
material (other than an ionic liquid) which enhances the
performance of an ionic liquid or whose performance is enhanced by
an ionic liquid.
[0022] The phrase "treatment composition" shall refer to a
composition resulting from contact of an ionic liquid with a second
corrosion inhibitor. The phrase shall include blends, mixtures,
complexes and reactions products of the ionic liquid and second
corrosion inhibitor.
[0023] As used herein, unless otherwise restricted, "inhibit",
"inhibiting" or "inhibition" shall include the inhibition,
prevention, reduction or control of corrosion of a metallic
surface.
[0024] The phrase "corrosion inhibitor" shall refer to a material
capable of inhibiting, preventing or reducing corrosion of a
metallic surface.
[0025] As used herein, "petroleum hydrocarbon fluid" shall include
crude oil, shale oil, shale gas condensate, bitumen, diluted
bitumen (dil-bit), refinery fractions including distillates
including gas oil cuts, finished fuel including diesel fuel,
petroleum fuel and biofuel, finished petroleum products, residual
oil, fuel gas, flare gas, propane, butane, liquefied petroleum gas
(LPG), natural gas liquid (NGL) and combinations thereof. The ionic
liquids and treatment compositions described herein are especially
useful in the treatment of crude oil, bitumen, diesel fuel,
petroleum fuel, biofuel, residual oil, fuel gas, flare gas,
propane, butane, liquefied petroleum gas (LPG), natural gas liquid
(NGL) and refinery fractions (including gas oil cuts and light
lubricating oils) and combinations thereof. In addition, any of
these may contain water, brines, gases such as hydrocarbon gases,
or a combination thereof.
[0026] As used herein, the word "conduit" may refer to any
pipeline, pipe, tubing, tubular, flow conduit, thoroughfare or
other artery in which a chemical, including a petroleum hydrocarbon
fluid, travels or contacts. The word "vessel" shall include any
equipment or container in which a petroleum hydrocarbon fluid is in
contact, such as heat exchangers, etc. The conduit may, but not
limited to, those composed of a metal, plastic or glass. The site
of the "conduit" or "vessel" shall include, but not be restricted
to reservoirs, wells, pipelines, refineries, fluid processing or
treatment facilities (including those where gas or oil production
or treatment occur, chemical plants, thermal power stations, power
plants, steel mills, natural gas processing plants, food processing
plants, semi-conductor plants and HVAC systems) as well as
thoroughfares leading to or from any of the above.
[0027] The ionic liquids and treatment compositions described
herein may be used during the production of crude oil and gas.
[0028] In addition, the ionic liquids and treatment compositions
may be used during the recovery of petroleum hydrocarbon fluids
from underground reservoirs.
[0029] The ionic liquids and treatment compositions are most useful
during the production of oil and gas from a well and during in a
refinery operation including light-ends recovery, solid waste and
cooling water treatment, process-water treatment, cooling, storage,
and handling, product movement, hydrogen production, acid and
tail-gas treatment and sulfur recovery.
[0030] The ionic liquids and treatment compositions may also be
used during the purification or another treatment phase of an
industrial product. For instance, the ionic liquids and treatment
compositions may be used to treat cooling water streams. Such
streams include produced water (aqueous fluids produced along with
crude oil and natural gas during from reservoirs water naturally
present in oil and gas bearing geological formations, aqueous
fluids produced or used during the production of oil and gas from
reservoirs or an industrial product, aqueous fluids produced during
the refining of oil and gas or an industrial product, aqueous
fluids used during the refining of oil and gas or an industrial
product, aqueous fluids used or produced during transit or storage
of petroleum hydrocarbon fluids or an industrial product).
Exemplary water streams include flowback water, degassed sour
water, boiler blowdown streams, cooling tower bleed-off/blowdown
(originating from oil refineries, petrochemical and natural gas
processing plants, other chemical plants, thermal power stations,
power plants, steel mills, food processing plants, semi-conductor
plants and HVAC systems). Wastewater streams from industrial
applications include municipal wastewater treatment facilities,
streams in transit to or from municipal wastewater treatment
facilities, tanning facilities, and the like. Exemplary products
removed during water treatments described herein may include
inorganic salts, polymers, breakers, friction reducers, lubricants,
acids and caustics, bactericides, defoamers, emulsifiers, filtrate
reducers, shale control inhibitors, phosphorus ions, ions of
calcium, magnesium and carbonates, bacteria as well other
production chemicals.
[0031] The ionic liquids and treatment compositions may also be
used within a conduit or vessel or introduced into a conduit or
vessel. The ionic liquids and treatment compositions may also be
used during transit of petroleum hydrocarbon fluids or an
industrial product as well as during storage of petroleum
hydrocarbon fluid or an industrial product.
[0032] The ionic liquid and treatment compositions are typically
liquid at relatively low temperature. While the ionic liquids are
salts, they typically exhibit high flash points, good solvency for
other chemicals and strong basicity.
[0033] Suitable ionic liquids as PIPPFLI are those of the formula
(I):
A.sup.+X.sup.- (I)
wherein A is or contains nitrogen or phosphorus, a nitrogen
containing heterocyclic ring or a phosphorus containing
heterocyclic ring; and X is an anion selected from the group
consisting of halides; hydroxyl; hydroxy containing nitrogen or
sulfur compounds; carbonates; alkyl carbonates; bicarbonates;
dithiocarbonates; trithiocarbonates; xanthates, thiocyanates;
alkoxides; carboxylates; hydroxycarboxylates; amino fatty acids;
anionic alkoxylated fatty acids; anionic metallic complexes, sulfur
or silicon containing anions; anionic phosphate esters, anionic
thiophosphate esters; anionic phosphonate esters; anionic
thiophosphonate esters; alkyl substituted phosphines; anionic urea;
anionic thiourea; anionic natural products; anionic thiols; anionic
phenols; anionic phenol resins; anionic copolymers of alpha olefins
and maleic anhydride, esters, amides, imides or derivatives
thereof; anionic acrylamido-methyl propane sulfonate/acrylic acid
copolymers; anionic polyacrylamides, anionic aminomethylated
polyacrylamides, anionic homopolymers, copolymers and terpolymers
of one or more acrylates, methacrylates and acrylamides, optionally
copolymerized with one or more ethylenically unsaturated monomers;
anionic phosphated maleic copolymers; an anionic homo or copolymer
of an oxirane or methyloxirane and mixtures thereof or a
zwitterion.
[0034] Further, ionic liquids of formula (II) or (III) may be used
as the PIPPCFI ionic liquid:
R.sup.1R.sup.2R.sup.3R.sup.4A.sup.+X.sup.- (II);
R.sup.1R.sup.2R.sup.3A.sup.+R.sup.8A.sup.+R.sup.5R.sup.6R.sup.7X.sup.-
(III)
wherein:
[0035] A in formula (II) is or contains nitrogen or phosphorus or a
heterocyclic ring thereof and wherein each A in formula (III) is
independently selected from nitrogen or phosphorus or a
heterocyclic ring thereof; and
[0036] X is an anion selected from the group consisting of halides;
hydroxyl; hydroxy containing nitrogen or sulfur compounds;
carbonates; alkyl carbonates; bicarbonates; carboxylates;
hydroxycarboxylates; sulfonates; sulfates; bisulfites;
thiocyanates; dithiocarbonates; trithiocarbonates; xanthates,
thiocyanates; carbamates; dithiocarbamates; sulfides; polysulfides;
alkoxides; anionic urea; anionic alkyl substituted phosphines;
anionic amino fatty acids; anionic alkoxylated fatty acids; anionic
acrylamido-methyl propane sulfonate/acrylic acid copolymers;
anionic phosphated maleic copolymers; anionic homo or copolymers of
an oxirane or methyloxirane; anionic metal complexes; sulfur or
silicon containing anions; anionic phosphate esters; anionic
thiophosphate esters; anionic phosphonate esters; anionic
thiophosphonate esters; anionic thiols; anionic natural products;
anionic phenols; anionic phenol resins; anionic homo or copolymer
of oxirane or methyloxirane; anionic copolymers of alpha olefins
and maleic anhydride, esters, amides, imides or derivatives
thereof; anionic alkyl substituted phosphines; anionic
polyacrylamides; anionic aminomethylated polyacrylamide, and
anionic homopolymers, copolymers and terpolymers of one or more
acrylates, methacrylates, acrylamides and acid; optionally
copolymerized with one or more ethylenically unsaturated monomers;
and mixtures thereof; and further wherein R.sup.1, R.sup.2,
R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are independently
selected from the group consisting of hydrogen; benzyl;
alkylbenzyl, or oxyalkyl (including --CH.sub.2CH.sub.2OH) or
--CH.sub.2CH(CH.sub.3)OH); a straight or branched alkyl group, an
alkylbenzyl group, an arylalkyl group, a straight or branched chain
alkenyl group, a hydroxyalkyl group or a hydroxyalkylbenzyl group;
and a polyoxyalkylene group; and R.sup.8 is a straight or branched
alkylene group, an alkylene oxyalkylene, or an alkylene
polyoxyalkylene or a zwitterion; and further wherein R groups may
be joined to form a heterocyclic nitrogen, sulfur or phosphorus
containing ring.
[0037] In an embodiment, cation of (I), (II) or (III) is phosphorus
or a phosphorus containing ring and X is an anion selected from the
group consisting of hydroxyl; hydroxy containing nitrogen or sulfur
compounds; bicarbonates; alkoxides; hydroxycarboxylates; silicon
containing anions; anionic amino fatty acids; anionic alkoxylated
fatty acids; anionic thiophosphonate esters; alkyl substituted
phosphines; anionic urea; anionic thiourea; anionic natural
products; anionic phenols; anionic phenol resins; anionic
copolymers of alpha olefins and maleic anhydride, esters, amides,
imides or derivatives thereof; anionic acrylamido-methyl propane
sulfonate/acrylic acid copolymers; anionic homopolymers, copolymers
and terpolymers of one or more acrylates, methacrylates and
acrylamides, optionally copolymerized with one or more
ethylenically unsaturated monomers; phosphated maleic copolymers;
an anionic homo or copolymer of an oxirane or methyloxirane and
mixtures thereof.
[0038] In another embodiment, cation A of formula (I), (II) or
(III) is or contains nitrogen or a nitrogen heterocyclic ring and
anion X is selected from the group consisting of silicon containing
anions; anionic thiophosphonate esters; anionic natural products;
anionic phenol resins; alkoxides; anionic copolymers of alpha
olefins and maleic anhydride, esters, amides, imides or derivatives
thereof or a mixture thereof; amino fatty acids; anionic
alkoxylated fatty acids; alkyl substituted phosphines; anionic
urea; anionic thiourea; anionic acrylamido-methyl propane
sulfonate/acrylic acid copolymers; anionic homopolymers, copolymers
and terpolymers containing acrylamide units; anionic phosphated
maleic copolymers; anionic oxirane or methyloxirane homo or
copolymers; and mixtures thereof.
[0039] In another embodiment, the ionic liquid represented by (II)
or (III) has a cation A of is nitrogen (for II) and each A in (III)
is nitrogen as defined herein and wherein X is an anion selected
from the group consisting of anionic metallic complexes; sulfur or
silicon containing anions; anionic phosphate esters; anionic
thiophosphate esters; anionic phosphonate esters; anionic
thiophosphonate esters; anionic thiols; anionic natural products;
anionic phenols; anionic phenol resins; anionic copolymers of alpha
olefins and maleic anhydride, esters, amides, imides or derivatives
thereof amino fatty acids; anionic alkoxylated fatty acids; alkyl
substituted phosphines; an oxirane or methyloxirane homo or
copolymer; anionic urea; anionic thiourea; anionic
acrylamido-methyl propane sulfonate/acrylic acid copolymers;
anionic homopolymers, copolymers and terpolymers containing
acrylamide units; anionic phosphated maleic copolymers and mixtures
thereof; and further wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4,
R.sup.5, R.sup.6 and R.sup.7 are independently selected from the
group consisting of hydrogen; benzyl; alkylbenzyl, or oxyalkyl
(including --CH.sub.2CH.sub.2OH) or --CH.sub.2CH(CH.sub.3)OH); a
straight or branched alkyl group, an alkylbenzyl group, an
arylalkyl group, a straight or branched chain alkenyl group, a
hydroxyalkyl group or a hydroxyalkylbenzyl group; and a
polyoxyalkylene group; and R.sup.8 is a straight or branched
alkylene group, an alkylene oxyalkylene, or an alkylene
polyoxyalkylene or a zwitterion; and further wherein R groups may
be joined to form a heterocyclic nitrogen, sulfur or phosphorus
containing ring.
[0040] Preferred ionic liquids are those of (III) having structures
R.sup.1R.sup.2R.sup.3R.sup.4N.sup.+;
R.sup.1R.sup.2R.sup.3N.sup.+R.sup.8N.sup.+R.sup.5R.sup.6R.sup.7;
S+R.sup.1R.sup.2R.sup.3; R.sup.1R.sup.2R.sup.3R.sup.4P.sup.+; and
R.sup.1R.sup.2R.sup.3N.sup.+R.sup.4P.sup.+R.sup.5R.sup.6R.sup.7.
[0041] In one preferred embodiment, anion X of (I), (II) or (III)
is a hydroxide, bicarbonate, carbonate, alkyl carbonate or an
alkoxide.
[0042] In a preferred embodiment, R.sup.1, R.sup.2, R.sup.3,
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 of formula (II) and (III) are
independently selected from the group consisting of a straight or
branched C.sub.1-30 alkyl group, a C.sub.7-30 alkylbenzyl group, a
C.sub.7-30 arylalkyl group, a straight or branched C.sub.3-30
alkenyl group, a C.sub.1-30 hydroxyalkyl group, a C.sub.7-30
hydroxyalkylbenzyl group, a zwitterion (such as those from
oxyalkylation of an amine with an alkylene oxide; or a
polyoxyalkylene group; and R.sup.8 is a straight or branched
C.sub.1-30 alkylene, an alkylene oxyalkylene, or an alkylene
polyoxyalkylene or R groups may be joined to form a heterocyclic
nitrogen, sulfur or phosphorus ring; and the anion comprises
halides, hydroxide, bicarbonate, carbonate, alkyl carbonates,
alkoxides, carboxylates, or a combination thereof; and further
wherein X.sup.- is hydroxide, bicarbonate, carbonate, alkyl
carbonates, alkoxides, carboxylates, or a combination thereof. In
an exemplary embodiment, A of formula (II) or (III) is nitrogen or
a nitrogen containing heterocyclic ring and anion X anion is a
hydroxide, bicarbonate, carbonate, alkyl carbonate or an
alkoxide.
[0043] In another preferred embodiment, R.sup.1, R.sup.2, R.sup.3,
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 of (II) and (III) are
independently --H or a C.sub.1-20 alkyl; wherein at least one (or
at least two) of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6 and R.sup.7 is a C.sub.2-20 alkyl, preferably a C.sub.6-12
alkyl.
[0044] Exemplary ionic liquids of formulas (I), (II) and (III)
include, but are not limited to, those ionic liquids having a
cation of dicocodimethyl ammonium and ditallowdimethyl ammonium.
Further specific exemplary ionic liquids are dicocodimethyl
ammonium hydroxide, benzyltrimethylammonium hydroxide,
ditallowdimethyl ammonium hydroxide, tributylmethylammonium methyl
carbonate, tetraethylammonium bicarbonate, tetrapropylammonium
hydroxide, coco dimethylethylammonium methyl carbonate, dodecyl
trimethylammonium hydroxide, (2-hydroxyethyl) cocoalkyl ammonium
hydroxide (including dialkyl, trialkyl, tetralkyl derivatives like
dicocodimethyl ammonium hydroxide cocotrimethyl ammonium
hydroxide), cocodialkylammonium chloride derivatives (such as
(oxydi-2,1-ethanediyl) bis(cocodimethylammonium) chloride),
tri-n-butyl methylammonium methyl carbonate, tetrabutylammonium
hydroxide, tallowtrimethyl ammonium hydroxide, cocotrialkyl
ammonium hydroxide (such as cocotrimethyl ammonium hydroxide),
cocodialkylammonium chloride derivatives (such as
(oxydi-2,1-ethanediyl) bis(cocodimethylammonium) chloride),
hydrogenated tallow trimethyl ammonium hydroxide, dihydrogenated
tallow dimethyl ammonium hydroxide, oxydiethylene
bis(cocodimethylammonium hydroxide having a structure represented
by the formula:
Coco(CH.sub.3).sub.2N.sup.+(CH.sub.2).sub.2O(CH.sub.2).sub.2N.su-
p.+(CH.sub.3).sub.2Coco (OH.sup.-).sub.2 or a combination
comprising at least one of the foregoing.
[0045] In some instances, the cation of (III) may be a polyamine,
meaning the cation may have two or more nitrogen atoms (and in some
cases up to 5 nitrogen atoms). In some instances, one or more of
the nitrogens of the polyamine may be cationic such that the cation
of (III) may be a polyamine containing two or more cationic sites
(and in some cases up to 5 cationic sites). In such cases, R.sup.8
may correspond to (--NR.sup.1R.sup.2).sub.y or
(--NR.sup.1R.sup.2R.sup.3).sub.y wherein y corresponds to 1, 2 or 3
to render the number of nitrogen sites and R.sup.1, R.sup.2 and
R.sup.3 are as defined above. Specifically, y is 1 when A is a
triamine, y is 2 when A is a tetramine and y is 3 when A is a
pentamine. Exemplary are cations of diethylenediamine,
triethylenetetraamine, tetraethylenepentamine and (bis)
hexamethylenetriamine. In other instances, where both of A are
phosphorus in (III), the cation may consist of multiple cationic
sites on the phosphorus wherein R.sup.8 may correspond to
(--PR.sup.1R.sup.2).sub.y or (--PR.sup.1R.sup.2R.sup.3).sub.y
wherein y corresponds to 1, 2 or 3 to render the number of
phosphorus sites and R.sup.1, R.sup.2, and R.sup.3 are as defined
above.
[0046] As used herein, the term "alkyl" refers to a straight or
branched chain, saturated monovalent hydrocarbon group regardless
whether straight or branched chain is specifically mentioned or
not; "aryl" refers to an aromatic monovalent group containing only
carbon in the aromatic ring or rings; "arylalkyl" refers to an
alkyl group that has been substituted with an aryl group, with
benzyl being an exemplary arylalkyl group; "alkylbenzyl" refers to
a benzyl group that has been substituted with an alkyl group in the
aromatic ring; "hydroxyalkyl" refers to an alkyl group that has
been substituted with a hydroxyl group with 2-hydroxyethyl as an
exemplary hydroxyalkyl group; "hydroxyalkylbenzyl" refers to a
benzyl group that has been substituted with a hydroxyalkyl group as
defined herein in the aromatic ring; "alkylene" refers to a
straight or branched chain, saturated, divalent hydrocarbon group,
and "alkenyl" refers to a straight or branched chain monovalent
hydrocarbon group having at least two carbons joined by a
carbon-carbon double bond. The term "substituted" as used herein
means that at least one hydrogen on the designated atom or group is
replaced with another group, provided that the designated atom's
normal valence is not exceeded. Substituted with a group means
substituted with one or more groups.
[0047] Suitable nitrogen containing heterocyclic rings referenced
herein include pyridinium, imidazolinium and a pyrrole cation
(including alkylated derivatives thereof). Further reference to
"nitrogen" shall include nitrogen containing cations such as an
oxyalkylated nitrogen.
[0048] In an embodiment, the cation of (I), (II) or (III) is a
quaternary amine salt, triethanolamine methyl chloride,
oxyalkylated amine, polyamine, oxyalkylated polyimines, cationic
melamine acid colloid or an oxyamine such as those of the formula
(CH.sub.3).sub.2N(CH.sub.2).sub.xOH where x is 1 to 6, preferably
2.
[0049] As used herein, a polyoxyalkylene group has a formula
##STR00001##
where each occurrence of R.sup.1 is independently a C.sub.1-10
alkylene or C.sub.2-8 alkylene, specifically ethylene, propylene,
butylene, or a combination thereof, and z is an integer greater
than 1 such as 2 to 30, 4 to 25, or 8 to 25.
[0050] An alkylene polyoxyalkylene group has a formula
##STR00002##
wherein R.sup.2 is a 01-30 alkylene, each occurrence of R.sup.3 is
independently a C.sub.1-10 alkylene or C.sub.2-6 alkylene,
specifically ethylene, propylene, butylene, or a combination
thereof, and y is an integer from 1 to 500, such as 2 to 30, 4 to
25, or 8 to 25.
[0051] An alkylene oxyalkylene group has a formula of
--R.sup.7--O--R.sup.8--, wherein R.sup.7 and R.sup.8 are each
independently a C.sub.1-20, or C.sub.1-10, or C.sub.1-5 branched or
straight chain alkylene. Optionally, R.sup.7 and R.sup.8 can be
ethylene.
[0052] Exemplary halides for the anion X.sup.- are --Cl, --Br, --F
and --I. In an embodiment --Cl is preferred.
[0053] Suitable sulfur and phosphorus containing anions include
sulfates (SO.sub.4.sup.-), bisulfate (HSO.sub.4.sup.-), thiocyanate
(SCN.sup.-), thiocarbonate
##STR00003##
dithiocarbamates
##STR00004##
wherein R.sub.1 and R.sub.2 are independently selected from
C.sub.1-20 alkyl groups, xanthates
##STR00005##
wherein R is a C.sub.1-20 alkyl, sulfides (RS.sup.-) wherein R is a
C.sub.1-20 alkyl, anionic polysulfides (RS(S).sub.xS.sup.-) wherein
R is a C.sub.1-20 alkyl and x is one to five, anionic phosphate
esters [ROP(.dbd.O)(OH).sub.2] and anionic phosphonate ester
[R--P(.dbd.O)(OH).sub.2 (wherein R is a C.sub.1-20 alkyl or a
C.sub.1-20 oxyalkyl-(RO--); anionic thiophosphate esters
##STR00006##
as well as anionic thiophosphonate esters (wherein R is a
C.sub.1-20 alkyl or a C.sub.1-20 oxyalkyl- (RO--); sulfonates
(RSO.sub.3.sup.-) wherein R is C.sub.1-20 alkyl or aryl or
alkylaryl group; and anionic thiols (RSH) where R is --(CH).sub.x)H
and x is from 1 to 4.
[0054] Exemplary oxirane or methyloxirane homo or copolymers
include those containing units of the structure
--(CH.sub.2CH.sub.2O).sub.xCH.sub.2CH(CH.sub.3)O).sub.y where x and
y are independently selected from 1 to 1500.
[0055] Exemplary anionic metal complexes in formulae (I), (II) and
(Ill) may include, but not be limited to Fe (such as Fe containing
anions like FeCl.sub.4.sup.-), aluminum (such as Al containing
anions like AlCl.sub.4.sup.-), etc. Further, the anionic metal
complex may be formed from copper, zinc, boron, tin and mixtures
thereof.
[0056] The anion may further be an anionic natural products like
anions of a polysaccharide, polyphenol or lignin. Suitable anions
of polysaccharides include anionic starches (such as mixtures of
amylose and amylopectin), anionic polyphenols (such as anionic
flavonoids or anionic natural polyphenols and anionic tannins (such
as water soluble anionic polyphenols with a molecular weight
between 500 and 3,000).
[0057] Suitable anions may also be anionic phenolics such as
anionic phenols, anionic alkyl substituted phenols, anionic phenol
oxyalkylates, anionic alkyl substituted phenol oxyalkylates,
anionic phenolic or alkylphenol resins and anionic phenol resin
oxyalkylates. Typically, the alkyl groups of the anionic phenolics
are C.sub.1-28.
[0058] The anion may also be an alkoxide. Suitable alkoxides
include those of the formula RO-- where R is a C.sub.1-30 alkyl or
cycloalkyl group. In an embodiment, R is C.sub.1-18 alkyl,
C.sub.6-12 aryl, or C.sub.5-12 cycloalkyl, Exemplary alkoxides are
tert-butoxide, n-butoxide, isopropoxide, n-propoxide, isobutoxide,
ethoxide, methoxide, n-pentoxide, isopentoxide, 2-ethylhexoxide,
2-propylheptoxide, nonoxide, octoxide, decoxide and isomers
thereof. Preferably, the alkoxides are tert-butoxide, isopropoxide,
ethoxide, or methoxide. Tert-butoxide and methoxide are
specifically mentioned. The alkoxides may further be anionic
ethylene or propylene oxide homopolymers, anionic copolymers or
terpolymers (which may optionally be crosslinked). Suitable
crosslinking agents include bisphenol A or maleic anhydride.
[0059] Suitable alkyl carbonates are those of the formula
ROCO.sub.2.sup.-, where R is a halogenated or non-halogenated
linear or branched alkyl, or hydroxyl alkyl group, preferably a
halogenated or non-halogenated linear or branched C.sub.1-8 or
C.sub.1-5 alkyl group.
[0060] Exemplary carboxylates include formate, acetate, propionate,
benzoate, n-butyrate, isobutyrate, pivalate, octanoate and laurate,
as well as anions of C.sub.18 fatty acids such as oleate, linolate
and stearate. Exemplary hydroxycarboxylates include glycolate,
lactate, citrate, glucarate, gluconate and tartrate.
[0061] Suitable anionic copolymers of alpha olefins and maleic
anhydride, esters, amides, imides (and derivatives thereof) include
those of the general structure
##STR00007##
where R is a C.sub.1-30 alkyl group.
[0062] Suitable alkyl carbonates, carboxylates, anionic metal
complexes, anionic natural products, anionic phenolics, alkoxides,
anionic alpha olefin/maleic anhydride polymers, anionic polymers of
acrylates, methacrylates and acrylamides and sulfur cations are
those referenced in the paragraphs above.
[0063] The ionic liquids of (I), (II), and (III) are salts having a
melting point range of -100.degree. C. to 200.degree. C., typically
below 100.degree. C. They are generally non-volatile and exhibit
low vapor pressures and are environmentally more benign than other
organic solvents, such as volatile aromatics and alkanes. They are
thermally stable over a wide temperature range with some having a
liquid range of up to 300.degree. C. or higher. Typically they are
molten salts of organic compounds or eutectic mixtures of organic
and inorganic salts. Stability and other fundamental physical
properties of the ionic liquids are influenced by the selection of
cation while the selection of anion generally determines the
functionality of the ionic liquid.
[0064] In an exemplary embodiment, ionic liquids disclosed herein
may be prepared by first forming a quaternary salt followed by ion
exchange with an acid or salt or by an anionic metathesis reaction
with an appropriate anion source to introduce the desired counter
anion. As an example, a nitrogen or phosphorus containing
heterocyclic compound (such as an imidazole or pyridine) may first
react with an alkylating agent to form the quaternary salt. The
alkylating agent may be an alkyl chloride providing a broad range
of alkyl groups on the nitrogen including straight and branched or
cyclic C.sub.1-C.sub.20 alkyl groups. The quaternary salt may then
be subjected to ion exchange with an acid or salt to form the ionic
liquid.
[0065] Ionic liquids (I), (II) and (III) may be tailored by varying
the cation and anion pairing may be combined with a second
corrosion inhibitor to form a treatment composition. In some
instances, the amount of ionic liquid in the treatment composition
may be from about 3 to about 99 weight percent.
[0066] In an embodiment, the anion of the ionic liquid may be the
same as the conjugate base of the second corrosion inhibitor. For
instance, a suitable ionic liquid may be prepared of formula (II)
or (Ill) where the cation is nitrogen, each of R.sub.1, R.sub.2,
R.sub.3 and R.sub.4 are hydrogen and anion A is a phosphonate. The
ionic liquid functions as a corrosion inhibitor. The treatment
composition may consist of the ionic liquid and the second
corrosion inhibitor. The conjugate base of the second corrosion
inhibitor is a phosphonate, the same as the anion of the ionic
liquid.
[0067] In some cases, corrosion inhibition improves when the ionic
liquid is used in combination with the second corrosion inhibitor.
The presence of the ionic liquid in the treatment composition may
boost the corrosion inhibition power of the second corrosion
inhibitor. (Likewise, the presence of the second corrosion
inhibitor in the treatment composition may boost the corrosion
inhibition power of the ionic liquid.) The combination of ionic
liquid and second corrosion inhibitor may therefore substantially
reduce the amount of corrosion and rate of corrosion onto the
metallic surface compared to when a fluid containing only one of
the ionic liquid or second corrosion inhibitor is used. In one
non-limiting example, the presence of the ionic liquid in the
treatment composition decreases the rate of corrosion onto a
metallic surface by at least 25% and sometimes 50% or higher.
[0068] The ionic liquids and/or treatment compositions described
herein may exhibit multiple functions. For example, an ionic
liquid(s) or treatment composition(s) may be effective as a scale
inhibitor as well as a corrosion inhibitor.
[0069] One or more ionic liquids and/or treatment compositions may
be concurrently used.
[0070] The second corrosion inhibitor is preferably a liquid
material. If the inhibitor is a solid, it may be dissolved in a
suitable solvent, thus making it a liquid.
[0071] The ionic liquid and treatment compositions are typically
introduced to their targeted location in an organic solvent or in
an aqueous fluid such as fresh water, brackish water, brine as well
as salt-containing water solutions such as sodium chloride,
potassium chloride and ammonium chloride solutions. Suitable
organic solvents include alkyl alcohols such as methyl alcohol,
ethyl alcohol, propyl alcohol, isopropyl alcohol and butyl alcohol
and alkylene glycols like ethylene glycol, propylene glycol. The
fluid containing the ionic liquid or treatment composition may
further contain one or more surfactants, mutual solvents,
sequestering agents, friction reducers, gelling agents, and other
conventional additives as well as mixtures thereof.
[0072] The amount of ionic liquid or treatment composition in the
organic solvent or aqueous fluid is dependent on the corrosive
conditions, temperature and intended time of contact. Typically,
the amount of ionic liquid or treatment composition in the fluid
introduced to the targeted site is from 1 ppm to about 5,000 ppm,
or about 1 ppm to about 500 ppm, or about 5 ppm to about 150
ppm.
[0073] In an embodiment an effective corrosion inhibiting or
preventative amount of the ionic liquid or treatment composition is
introduced to an acidic fluid prior to introduction of the acidic
fluid into a targeted well or conduit. This may especially be the
case where the ionic liquid or treatment composition is used during
a well treatment operation as discussed below.
[0074] When use of a treatment composition is desired, the ionic
liquid and second corrosion inhibitor are first combined and then
introduced into the targeted location in the organic solvent or
aqueous fluid. At times however, the ionic liquid and second
corrosion inhibitor may be introduced in different stages.
[0075] The ionic liquid and treatment compositions dramatically
inhibits the amount of corrosion and the rate of corrosion on
metallic surfaced caused by aqueous acids including mineral acids,
like hydrochloric acid, hydrofluoric acid, sulfuric and phosphoric
acids as well as weak acids, such as formic acid, acetic acid,
hydroxyacetic acid, citric acid, phosphonic acid, methanesulfonic
acid and propionic acid as well as other acids affecting industrial
operations.
[0076] Inhibition of corrosion may be seen on a wide host of
metallic surfaces including iron, chromium, ferrous base metals,
alloys of steel, alloys of nickel, duplex steels, stainless steel,
chrome steel, martensitic alloy steel, ferritic alloy steel, carbon
steel, precipitation-hardened stainless steels and the like.
Pitting is dramatically reduced when the ionic liquids and
treatment compositions are used.
[0077] The ionic liquids and treatment compositions may be
contacted with a hydrocarbon-containing stream under severe
conditions of heat, pressure, agitation and/or turbulence. They may
be used at a wide variety of temperatures, typically ranging from
120.degree. F. to 180.degree. F. as well as up to 350.degree. F.
beyond.
[0078] The ionic liquids and treatment compositions are very useful
in the inhibition of corrosion of metallic surfaces during well
treatment operations. The treated well may be a hydrocarbon
producing well, such as a gas or oil well, or non-hydrocarbon
producing wells, such as water injection wells, water producing
wells or geothermal wells. They can be used during various types of
treatment operations that occur in or before the wellbore and in
subterranean formation applications. For example, they can be used
in pickling a tubular, cleaning a wellbore, scale treatment, and
coiled tubing applications. They can also be used in matrix acid
stimulation, acid fracturing, acid tunneling, drilling mud removal,
scale treatment, coiled tubing application, or damage removal. Any
known method of introducing the ionic liquid(s) or treatment
composition(s) into the reservoir can be used. In all of these
applications, the ionic liquids and treatment compositions protect
metal tubulars and alloy surfaces from acidic fluids that are
introduced or produced downhole.
[0079] The ionic liquids and treatment compositions can also be
used to inhibit corrosion during refining of hydrocarbon fluids,
during transport or storage of the fluids or during any period in
between.
[0080] Further, the ionic liquids and treatment compositions are
highly useful in the prevention or inhibition of corrosion
attributable to carbon dioxide and hydrogen sulfide. The hydrogen
sulfide may be formed when the treating acid contacts a
sulfur-containing mineral, such as iron sulfide.
[0081] The ionic liquids and treatment compositions are further
particularly effective in the treatment of cooling towers relying
on aqueous fluids for the removal of heat from one medium to
another. As such, the ionic liquids and treatment compositions may
be used in oil refineries, petrochemical and other chemical plants,
thermal power stations and power plants, steel mills, natural gas
processing plants, food processing plants, semi-conductor plants as
well as HVAC systems.
[0082] Exemplary ionic liquids as corrosion inhibitors include
those wherein X in (I), (II) or (Ill) is an anionic phosphate
ester, anionic thiophosphate ester, anionic phosphonate ester;
anionic thiophosphonate ester; anionic diphosphonic acid; and
anionic carboxylic acids (such as anionic glucaric acid).
[0083] Exemplary corrosion inhibitors further those wherein the
cation is pyridinium or an imidazolinium as well as quat ammonium
halides such as quat ammonium chlorides.
[0084] Other corrosion inhibitors include hydroxyl containing
nitrogen or sulfur compounds such as alkylated thiols such as those
of the formula HS(CH.sub.2).sub.xOH where x is from 1 to 8, like
HSCH.sub.2CH.sub.2OH; anionic sulfonyl alcohols such as
2-(methylsulfonyl) ethanol; 2-sulfanylethanol; 2-sulfanyl,
propan-1-ol; 2-sulfanylbutan-2-ol; 1-sulfanylbutanol-2-ol and
mixtures thereof.
[0085] Exemplary ionic liquids include those of structure (IV):
##STR00008##
wherein R is a C.sub.12-C.sub.18 alkyl or alkenyl group and X is
--OH, NH.sub.2 or C(.dbd.O)R; exemplary phosphate esters or
thiophosphate esters are those having one of structures (VA) or
(VB):
##STR00009##
wherein R is an alkyl or
RO(CH.sub.2CH.sub.2O).sub.nCH.sub.2CH.sub.2) and R'' and R''' are
independently selected from --H and a C.sub.1-C.sub.20 alkyl;
exemplary quat ammonium chlorides are those of structure (VI):
##STR00010##
wherein the alkyl group may contain from 1 to 20 carbon atoms; and
exemplary alkyl pyridine quats are those of structure (VII):
##STR00011##
wherein R is a C.sub.1-C.sub.18 alkyl or benzyl. In an embodiment,
more than one R group can be a substituent to the pyridinyl ring.
In such case, the second R group is typically a C.sub.1-C.sub.12
alkyl group.
[0086] Further exemplary corrosion inhibitors include thiazoles,
triazoles and thiadiazoles such as benzotriazole, tolyltriazole,
octyltriazole, decyltriazole, dodecyltriazole,
2-mercaptobenzothiazole, 2,5-dimercapto-1,3,4-thiadiazole,
2-mercapto-5-hydrocarbylthio-1,3,4-thiadiazoles,
2-mercapto-5-hydrocarbyldithio-1,3,4-thiadiazoles,
2,5-bis(hydrocarbylthio)-1,3,4-thiadiazoles, and
2,5-(bis)hydrocarbyldithio)-1,3,4-thiadiazoles.
[0087] Suitable anionic groups for anion X of formula (I), (II) and
(III) include the counter anions of any of the corrosion inhibitors
referenced above. For example, anion X of ionic liquid of formula
(I), (II) and (III) may be an anionic phosphate ester, anionic
thiophosphate ester, anionic phosphonate ester, anionic
thiophosphonate ester, an anionic thiol, etc.
[0088] In a preferred embodiment, a treatment composition may be
used for the inhibition, prevention or reduction of corrosion of
metals; the treatment composition comprising the ionic liquids set
forth above and one or more corrosion inhibitors (other than an
ionic liquid). Exemplary corrosion inhibitors include those set
forth in the paragraphs above. In an embodiment, the anion X of the
formula (I), (II) and (III) of the treatment composition may be the
same anion as the counter anion of the corrosion inhibitor. For
example, the treatment composition may contain (as corrosion
inhibitor), the ionic liquid of (II) wherein R.sup.1, R.sup.2,
R.sup.3 and R.sup.4 are hydrogen and anion X is the counter cation
of (I) above.
[0089] Pitting of metallic surfaces decreases when metallic
surfaces are contacted with the ionic liquids and/or corrosion
inhibiting treatment compositions described in the paragraphs
above.
[0090] Further, corrosion inhibiting treatment compositions have
been noted to provide a synergistic effect compared to the ionic
liquid or the corrosion inhibitor by themselves. i.e., inhibition,
prevention and/or reduction of corrosion significantly increases
when fluids are contacted with a corrosion inhibiting treatment
composition versus contacting of the metallic surface with the
ionic liquid or corrosion inhibitor by themselves.
EXAMPLES
[0091] All percentages set forth in the Examples are given in terms
of weight units except as may otherwise be indicated.
Example 1
[0092] An anion exchange method was followed to prepare sulfur
based ionic liquids. A general procedure for the anion exchange
method was followed wherein about 1 gram of KOH was dissolved in 5
grams methanol. About 1.36 grams 2-mercaptoethanol was added while
stirring at 60.degree. C. for 15 minutes. About 5 grams of a
solution of N-benzyl, 2 methyl pyridinium chloride (75%) in
methanol (25%) was then added dropwise and the mix stirred at
60.degree. C. After 30 minutes of stirring, the solution was
filtered while still hot to remove the potassium chloride
by-product. The product was characterized by the replacement of the
chloride on the pyridinium by the mercaptide of the
2-mercaptoethanol.
[0093] A second procedure which avoided the need to filter the
product. The following general procedure was followed. About 1.36
grams of 2-mercaptoethanol was added with stirring at room temp to
8 grams 55% aqueous tetrabutylammonium hydroxide. A slight exotherm
occurred on mixing. The mixture was stirred for 15 minutes at
60.degree. C. before 27 grams of a solution containing 36%
oxydi-2,1-ethanediyl) bis(cocodimethylammonium) dichloride in 30%
water & 30% methanol was added dropwise. The solution was
stirred for 30 minutes at 60.degree. C. and cooled and used in all
testing without further modification. No filtration was required as
the tetrabutylammonium chloride by-product formed in the reaction
was soluble in the product.
[0094] The synthesis of ionic liquids may be illustrated as
follows:
##STR00012##
[0095] A kettle test run was under the conditions of 10 ppm
additive in a brine with a carbon dioxide sparge, run for 18 hours
at 180.degree. F. and the corrosion rate (CR) monitored using
linear polarization resistance (LPR) probes. The results are set
forth in Table I.
TABLE-US-00001 TABLE I Additive Dose 17.8 Additive (ppm) Hour CR
Untreated None 273 (303) oxydi-2,1-ethanediyl) bis(cocodimethyl- 10
233 ammonium) dichloride (ODEBCAC) 2 mercaptoethanol (2ME) 10 76
ODEBCAC/2ME 1:2 salt 10 12 (8) ODEBCAC/2ME 1:1 salt 10 12 N-Octyl
pyridinum/2 ME salt 10 11 (8) N-Dodecyl pyridinium/2 ME salt 10 1
(2) N-Hexadecyl pyridinium/2 ME salt 10 1 (2) N benzyl 2 methyl
pyridinium chloride 10 279 (NBMPC) NBMPC/2 ME salt 10 4 (4) NBMPC +
sodium trithiocarbonate 2:1 10 49 salt NBMPC +
1,8-Dimercapto-3,6-dioxa- 10 10 octane (DMDO) 2:1 salt NBMPC + DMDO
1:1 salt 10 10
Example 2
[0096] A neutralization procedure was used to prepare ionic
liquids. The general procedure for all tests may be represented by
preparation of tetra-n-butylammonium bitartrate (1:1 salt) wherein
tartaric acid (10 grams, 0.067 moles) was added in portions to a
stirred solution of 55% aqueous tetra-n-butylammonium hydroxide
(31.6 grams, 0.067 mole). A slight exotherm occurred during the
addition. The solution was stirred at room temperature for an
additional 30 minutes before testing without further modification.
The samples were then subjected to a kettle test using synthetic
cooling water and the corrosion rate was monitored using linear
polarization resistance (LPR) probes. The results are set forth in
Table II.
TABLE-US-00002 TABLE II Corrosion Rate Active Dose @ 18 hours
Additive (ppm) (MPY) Tetra-n-butylammonium bi-tartrate 98 '' 65 3.7
Tetramethylammonium bi-tartrate 71 5.7 '' 47 5.0 Tetraethylammonium
bi-tartrate 60 3.9 Ethyl trimethylammonium b-tartrate 57 3.3 '' 38
19.0 Benzyltrimethylammonium bi-tartrate 45 12.4
Dodecyltrimethylammonium bi-tartrate 98 16.3
(2-hydroxyethyl)trimethylammonium bi- 65 2.2 tartrate
Tetra-n-butylammonium citrate 1:1 salt 90 0.8 Tetraethylammonium
citrate 2:1 salt 90 1.0 Tetraethylammonium citrate 1:1 salt 110 1.6
Tetra-n-butylammonium bi-glucarate 86 2.0 (1:1 salt)
Tetraethylammonium malate 1:1 salt 100 23.9
(2-hydroxyethyl)trimethylammonium 90 33.8 citrate 1:1 salt
(2-hydroxyethyl)trimethylammonium 90 37.1 citrate 2:1 salt
* * * * *