Alkylbenzenesulfonic acids and corresponding salts for enhanced oil recovery

Abstract

The present invention relates to a composition comprising alkylbenzenesulfonate isomers, wherein the composition comprises structural isomers ABS(I) and ABS(II) in a molar ratio ABS(I):ABS(II) ranging from 10:90 to 30:70, and wherein the composition comprises at least one further alkylbenzenesulfonate selected from ABS(III), ABS(IV) and ABS(V). Furthermore, the present invention relates to a process for the manufacture of these compositions and to the use of these compositions in oilfield and enhanced oil recovery applications.

Description

Background Technology

[0001] In industrialized economies, crude oil has been the most important energy source and the starting material for many products of the chemical industry since the early 20th century. It is typically produced from underground deposits formed over millions of years. Therefore, global reserves are finite, and these deposits are generally considered to be depleted within the next few decades. Given this, maximizing the amount of oil recovered from exploited deposits is generally desired. Oil recovery from underground deposits can typically be divided into primary, secondary, and tertiary recovery stages.

[0002] A primary recovery involves a stage of oil production during which oil can be extracted from an underground deposit by means of the natural pressure of the deposit (which pushes the oil from the deposit to the surface through drilling). A primary recovery typically allows...

[0003] Mining the deposits yields approximately 5% to 10% oil.

[0004] When the natural pressure of a mineral deposit is exhausted and further extraction by primary recovery is not possible, or if the pressure naturally present in the deposit is insufficient to extract oil, secondary recovery is typically employed. This involves injecting pressurized water or gas into the deposit to drive the remaining oil after the primary recovery phase. This is achieved through so-called deficit filling (i.e., increasing and / or re-establishing the natural pressure present at the start of oil extraction) and by sweeping or displacing oil from the deposit to push it towards a well (through which it is transported to the surface). If the material injected into the deposit is water, this technique is also known as waterflooding. Secondary recovery typically allows for the extraction of an additional 20% to 30% of the oil in the deposit.

[0005] Tertiary recovery specifically involves a stage of oil production during which chemicals such as polymers, alkalis, surfactants, or combinations of such chemicals are injected into the deposit to improve the flow of the remaining oil after the primary and secondary recovery stages. This is also known as chemical flooding or chemical enhanced oil recovery (often abbreviated as EOR). Tertiary recovery typically allows for the extraction of an additional 10% to 20% of the oil in the deposit.

[0006] Injecting surfactants into the deposit reduces the interfacial tension between oil and water and / or deposit sediments. This, in turn, enhances the displacement of oil droplets through the deposit.

[0007] Alkylbenzene sulfonates are among the most well-known surfactants available for a wide range of applications requiring surfactants (detergents, hard surface cleaners, drilling fluids, cutting fluids, wetting agents, emulsifiers for agricultural herbicides, emulsion polymerization, etc.), and they have been considered promising for enhancing oil recovery through surfactant-polymer flooding and surfactant-polymer flooding. The key differences between alkylbenzene sulfonates used in household detergents and EOR applications will be discussed later in this introduction.

[0008] Alkylbenzene sulfonates are typically formed by alkylating benzene with an alkene or a partially dehydrogenated alkane to form a linear alkylbenzene (LAB) (which contains a hydrocarbon group attached to a benzene ring). The LAB is then subjected to sulfonation, in which a sulfonic acid group is chemically bonded to a carbon atom in the benzene ring structure of the LAB. Thus, the resulting linear alkylbenzene sulfonate (LAS) contains a hydrophilic sulfonate group and a hydrophobic hydrocarbon moiety. Alkylation and sulfonation methods that can be used to form compositions of LAB and LAS are well known. See, for example, U.S. Patent No. 6,887,839.

[0009] LAS are commonly used in EOR applications not only because they reduce the interfacial tension between oil and water, but also because they exhibit the desired phase behavior when combined with varying amounts of other salts, such as sodium chloride. Crude oil in the deposit will form microemulsions with a well-tailored EOR composition containing LAS (for optimal phase behavior matching). The large amounts of oil and water dissolved in the microemulsions create ultra-low interfacial tension, offering the potential for high oil recovery in the reservoir.

[0010] However, some LASs exhibit properties that make them undesirable for EOR applications or for the preparation of surfactant concentrates (which are later used to prepare the final compositions for EOR applications). Some of these undesirable properties are high viscosity, high pour point, low solubility of sodium sulfate and / or calcium sulfate, or failure to achieve low interfacial tension (IFT) between crude oil and brine. Therefore, research is needed to provide LAS compositions that do not exhibit any of these undesirable properties.

[0011] Returning to the key points: the difference between LAS used in household detergents or similar applications and LAS used in EOR applications is the alkyl chain length. LAS currently sold for household detergent applications typically contain C10-C13 alkyl chains and are the world's best-selling synthetic surfactants, with sales of approximately 4.7 million tons in 2022. There are numerous facilities worldwide with well-established and efficient manufacturing processes for C10-13 LAS. This is well-known from the analysis of the LAB and LAS market. See, for example, Chemanalyst's "Decode the Future of Linear Alkyl Benzene (LAB)" (September 2023) https: / / www.chemanalyst.com / industry-report / linear-alkyl-benzene-market-278 and STPP Group's "Linear alkyl benzene sulphonicacid (LABSA)" https: / / stppgroup.com / products / detergent-chemicals / labsa / .

[0012] On the other hand, LAS used in EOR applications typically contain C15-C17 alkyl chains. Due to the low demand for C15-C17 LAS, currently no facilities have been established or only a few have been built for their production. If a larger quantity of C15-C17 LAS is required, significant energy and building material investments are needed to establish new manufacturing plants. Therefore, considering resource efficiency (i.e., maximizing the benefits of current resources), LAS compositions that can be successfully used in EOR applications and are at least partially made from already available "detergent" LAS will help minimize energy and material consumption. Furthermore, since no new manufacturing plant for "EOR" C15-C17 LAS is required, indirect energy and material savings can be achieved. And therefore, it will have a positive environmental impact. Existing technology

[0013] US 2009 / 0111717 A1 and WO 2009 / 058889 A1 describe formulations for enhancing oil recovery, which contain alkyl aryl sulfonates as primary surfactants, aliphatic sulfonates as secondary surfactants, cosolvents, passivators, and polymers.

[0014] WO 2009 / 079289 A1 describes a method for enhancing oil recovery by injecting a surfactant-polymer formulation described in US 2009 / 0111717A1 and WO 2009 / 058889 A1 into the reservoir via a wellbore and subsequently injecting a chaser solution.

[0015] WO 2017 / 174770 A1 describes compositions and methods for enhancing oil recovery, comprising dialkylbenzene sulfonate, alkyl diphenyl ether disulfonate, polyacrylamide, alkali and water.

[0016] US 2018 / 0057453 A1 describes a method for preparing a surfactant composition comprising a dialkylbenzene sulfonate (the alkyl portion independently comprising no more than 15 carbon atoms) and a linear alkylbenzene sulfonate.

[0017] WO 2014 / 055225 A1 describes surfactant compositions for treating oil-bearing underground formations, comprising alkyl aryl sulfonates and biodegradable chelating agents including ethylenediamine disuccinic acid or salts thereof.

[0018] WO 2013 / 000571 A1 describes surfactant compositions comprising alkyl aryl sulfonates and their use in enhanced oil recovery. The alkyl chain of the alkyl aryl sulfonate comprises 9 to 10 carbon atoms, and at least 20% of the molecule has a branched alkyl chain in which methyl or ethyl is a side-chain substituent.

[0019] WO 2000 / 037775 A1 describes a method for enhancing oil recovery, in which alkylaryl sulfonates are used, prepared by alkylating an aromatic compound with an α-olefin stream having a wide distribution of olefin carbon numbers.

[0020] WO 2015 / 138275 A1 describes surfactant compositions that may contain alkylbenzene sulfonic acid. Summary of the Invention

[0021] This invention relates to a composition comprising alkylbenzene sulfonates ABS(I) and ABS(II).

[0022] (I) (II)

[0023] in

[0024] R 1 and R 2 Independently selected from saturated alkyl groups containing 2 to 13 carbon atoms;

[0025] R 1 and R 2 Together they have a total of 15 carbon atoms;

[0026] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;

[0027] The molar ratio of ABS(I):ABS(II) ranges from 10:90 to 30:70.

[0028] In one embodiment, the composition comprises at least one additional alkylbenzene sulfonate molecule selected from ABS(III), ABS(IV), ABS(V), and mixtures thereof.

[0029] (III) (IV) (V)

[0030] in

[0031] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;and

[0032] The molar ratio of alkylbenzene sulfonates [(I)+(II)] : [(III)+(IV)+(V)] ranges from 90 : 10 to 99.9 : 0.1;

[0033] Alkylbenzene sulfonates (I)-(V) can be collectively referred to as ABS mixture "Group A".

[0034] Furthermore, the present invention relates to concentrated blends and EOR compositions prepared from the ABS compositions of the present invention, their uses in oilfields and EOR applications, and methods for successfully recovering crude oil by treating underground wellbores with the EOR compositions to form Winsor III type emulsions.

[0035] Surprisingly, the ABS compositions of the present invention offer several advantages.

[0036] First, the ABS composition of the present invention (wherein M) + = H +At ambient temperature, ABS is a liquid and has low viscosity. This facilitates pumping the material into and out of transport vehicles (e.g., container trucks) and thus helps transport ABS compositions to other locations (e.g., remote reservoirs). If ABS compositions are not pumpable at high concentrations, they must be diluted to make them easily pumped into and out of transport vehicles. Therefore, compared to transporting diluted aqueous solutions with only about 10-20 wt% active material, if the composition has low viscosity even when containing high concentrations of ABS (e.g., above 60 wt.%, preferably above 80 wt.%) and low water content (e.g., below 5 wt.%, preferably below 2.5 wt.%), less transport capacity (e.g., fewer trucks) is required. This results in significant energy savings.

[0037] Secondly, the ABS composition of the present invention (wherein M) + = H + It has a low pour point, that is, a pour point < -21°C.

[0038] The low viscosity and low pour point allow for easy operation of surfactant compositions in remote reservoir locations with limited infrastructure: under ambient conditions, heating is not required to store the mixture, and conventional pumps can be used due to the relatively low viscosity. Furthermore, the low pour point facilitates the operation of ABS compositions at lower ambient temperatures, such as in winter or in colder regions.

[0039] Third, by mixing the ABS composition of the present invention (in acidic form), a neutralizing agent, and a second surfactant, a concentrated blend containing a high surfactant concentration and low water content can be prepared, exhibiting low viscosity at 65°C and a pour point below 20°C. In addition to transporting a single surfactant component (e.g., the ABS composition), transporting the surfactant blend as a concentrate is also an option. For EOR applications, alkylbenzene sulfonic acids are neutralized with, for example, Na₂CO₃ or NaOH to obtain the corresponding sodium salts, and these are often mixed with other surfactants (such as polyalkoxylated surfactants). The manufacture of these concentrated blends may take place at a location far from underground oil wellbores, and therefore, the transport of the concentrated blends is necessary. For the same reasons explained above, it is desirable for concentrated blends containing a high content of active surfactants to have low viscosity and a low pour point, allowing the material to be easily pumped into and out of transport devices with less transport capacity and energy required. This is achieved by preparing concentrated blends by mixing the ABS composition of the present invention with at least one additional surfactant.

[0040] Fourth, a clear and stable composition for EOR applications containing 0.05 to 2 wt.% surfactant can be prepared from the ABS composition of the present invention. The EOR composition contains at least an alkylbenzene sulfonate, any impurities from the ABS preparation steps (e.g., sulfonic acid), any residual portion of Na₂CO₃ or NaOH from the neutralization step, and (if desired) a second surfactant. For a successful EOR process, it is important that the EOR composition is clear, homogeneous, and stable. If the EOR composition is turbid and tends to precipitate, for example due to the formation of sodium sulfate (from the residual portion of sulfonic acid and Na₂CO₃ or NaOH) or calcium sulfate (from the residual portion of sulfonic acid in contact with formation water containing divalent cations such as calcium cations), there is a risk that porous reservoirs (such as sandstone or carbonate reservoirs) may be blocked and the oil recovery process will be unsuccessful.

[0041] The ABS composition of this invention contains less than 2 wt.% sulfuric acid. This also contributes to the clear and stable appearance of the ABS composition and reduces the risk of clogging porous reservoirs, such as sandstone or carbonate reservoirs.

[0042] Fifth, when using the EOR composition prepared from the ABS composition of this invention, ultra-low IFT (< 0.01 mN / m) between crude oil and brine can be achieved. When the EOR composition prepared from the ABS composition of this invention comes into contact with crude oil, a Winsor III type microemulsion is formed. These types of microemulsions enable efficient mobilization of crude oil during EOR operations.

[0043] In one embodiment of the invention, the ABS composition further comprises “Group B” alkylbenzene sulfonic acid or a salt thereof, wherein the weight ratio of “Group A” to “Group B” in the ABS mixture ranges from 95:5 to 70:30. These compositions of the invention exhibit all the desired properties mentioned above regarding ABS compositions comprising “Group A” ABS.

[0044] "Group B" ABS is a byproduct / undesirable product derived from the manufacture of C10-C13-Ph (a raw material for C10-C13 ABS, a synthetic surfactant used in applications such as detergents). As mentioned in the "Background Art" section, C10-C13 ABS is currently the world's best-selling synthetic surfactant, with sales of approximately 4.7 million tons in 2022. By blending "Group B" ABS, based on already available alkylbenzene streams, with "Group A" ABS, for which there are currently few efficient manufacturing plants, the overall manufacturing demand for "Group A" ABS is reduced. This results in a reduction in the energy and materials required to establish new manufacturing plants for "EOR" C15-C17 LAS, and therefore has a positive environmental impact.

[0045] In one embodiment of the invention, the ABS composition further comprises “Group C” alkylbenzene sulfonic acid or a salt thereof, wherein the weight ratio of “Group A” to “Group C” in the ABS mixture ranges from 25:75 to 97.5:2.5, preferably 50:50 to 97.5:2.5, more preferably 70:30 to 95:5, and even more preferably 85:15 to 95:5. These inventive compositions exhibit all the desired properties mentioned above for ABS compositions comprising “Group A” ABS, and it has been unexpectedly found that the addition of “Group C” ABS surfactant further improves the solubility of the surfactant concentrate in water and reduces the viscosity of the surfactant concentrate, and thus facilitates the preparation of EOR compositions.

[0046] definition

[0047] As used herein, unless expressly stated otherwise, the following terms shall have the following meanings:

[0048] As used herein, the term "LAB" refers to linear alkylbenzene compounds.

[0049] As used herein, the term "LAS" refers to linear alkylbenzene sulfonic acid or its corresponding salt.

[0050] As used herein, the term "ABS" refers to alkylbenzene sulfonic acid or its corresponding salt, which may be linear or branched.

[0051] As used in this article, the term "enhanced oil recovery" or "EOR" refers to methods used to improve the recovery of hydrocarbons from underground reservoirs.

[0052] As used herein, the term “active substance” refers to the concentration of a surfactant substance (i.e., LAS or a secondary surfactant or co-surfactant).

[0053] As used herein, the term “interfacial tension” or “IFT” refers to the surface tension between petroleum and water with different salinity containing formulations of different concentrations of surfactants.

[0054] The term "2-alkyl isomer" refers to an alkyl group attached to an aromatic ring, wherein the longest alkyl chain is attached to the aromatic ring at the 2-position of the alkyl chain.

[0055] As used herein, the term "TSP" refers to industrial-grade tristyrylphenol (meaning that industrial-grade TSP contains small amounts of stilbene and monostyrylphenol in addition to tristyrylphenol). Styrylated phenol can also be used as an alternative to industrial-grade TSP.

[0056] As used herein, the term "ABS composition" refers to a composition containing a high content of alkylbenzene sulfonic acid or its salt (as a single surfactant type) and a low water content.

[0057] As used herein, the term "concentrated blend" refers to a composition comprising a high content of surfactant and a low content of water, wherein the composition comprises an alkylbenzene sulfonate and a second surfactant.

[0058] As used herein, the term “EOR composition” refers to a composition containing a low amount (i.e., between 0.05 and 2 wt.%) of a surfactant, which can be directly injected into at least one injection well during EOR operation, and wherein the composition contains at least an alkylbenzene sulfonate as a surfactant and an optional second surfactant.

[0059] Unless otherwise stated, all percentages are by weight and pressures are in atmospheres. Detailed Implementation

[0060] In one embodiment of the invention, the ABS composition comprises an alkylbenzene sulfonic acid or a salt thereof according to "Group A" of the ABS mixture.

[0061] In another embodiment, the ABS composition additionally comprises an alkylbenzene sulfonic acid or a salt thereof according to ABS mixture "Group B", or ABS mixture "Group C", or ABS mixture "Group B" and "Group C".

[0062] The ABS mixtures “Group A”, “Group B” and “Group C” will be described in more detail below.

[0063] In embodiments of the invention, the pumpable concentrated blend can be prepared by mixing any ABS composition containing alkylbenzene sulfonate with a second surfactant or by mixing an ABS composition containing alkylbenzene sulfonate with a neutralizer and a second surfactant.

[0064] In embodiments of the invention, EOR compositions can be prepared by diluting any ABS composition or concentrated blend with at least water or brine. The EOR compositions contain a low surfactant content (i.e., between 0.05 and 2 wt.%), and may optionally contain a second surfactant in addition to the ABS surfactant.

[0065] Any composition described herein may contain additional components selected from the following list, including but not limited to second surfactants, polymers, solvents, alkalis, biocides, oxygen scavengers, scale inhibitors, and corrosion inhibitors. Suitable examples of these additional components are provided in more detail below.

[0066] ABS mixture "Group A"

[0067] The surfactant in group (A) is selected from the structure ABS(I)-(V).

[0068] (I) (II)

[0069] (III) (IV) (V)

[0070] in

[0071] R 1 and R 2 Independently selected from saturated alkyl groups containing 2 to 13 carbon atoms;

[0072] R 1 and R 2 Together they have a total of 15 carbon atoms;

[0073] M + Independently selected from H + NH4 + Or a monovalent cation, preferably M + It is H + NH4 + Na + or K + .

[0074] In one embodiment of the present invention, the molar ratio of ABS(I):ABS(II) in the ABS composition ranges from 10:90 to 30:70, preferably from 13:87 to 27:73, and more preferably from 15:85 to 25:75.

[0075] In one embodiment of the present invention, the molar ratio of alkylbenzene sulfonates [(I)+(II)] : [(III)+(IV)+(V)] in the ABS composition ranges from 90 : 10 to 99.9 : 0.1.

[0076] In another embodiment, the ABS composition may contain other alkylbenzene sulfonate molecules different from the ABS mixture "Group A", and in this case, the amount of the ABS mixture "Group A" is based on a total weight of at least 50 wt.%, preferably at least 60 wt.%, and more preferably at least 70 wt.% of all alkylbenzene sulfonate molecules present in the composition.

[0077] In another embodiment, at least 90%, preferably at least 95%, of the alkyl chain of the alkylbenzene sulfonic acid or its salt in "Group A" is straight-chain.

[0078] In a preferred embodiment, the SO3M groups in ABS(I) and ABS(II) are independently located at the ortho or para position, preferably at the para position.

[0079] The surfactant of group (A) can be obtained by alkylating benzene with a predominantly linear C16 α-olefin using an HF catalyst (or alternatively, a DETAL catalyst). The alkylbenzene mixture obtained by alkylating benzene with an α-olefin having 16 carbon atoms may additionally contain higher alkylating compounds that were not removed during purification steps (e.g., distillation). The resulting alkylbenzene mixture is liquid at room temperature and exhibits a refractive index of 1.479–1.482 (at 20°C, according to ASTM D-1218).

[0080] The alkylbenzene mixture can then be sulfonated in a falling film reactor using a sulfonating agent (such as sulfur trioxide).

[0081] Alternatively, alkylbenzene sulfonic acids can be neutralized with a base (such as sodium hydroxide) to form the corresponding salt.

[0082] ABS mixture "Group B"

[0083] The surfactants of group (B) are selected from dialkylated or trialkylated alkylbenzene sulfonic acids or their corresponding salts, wherein the sum of all carbon atoms in the alkyl chain is primarily in the range of 10 to 20, but none of the alkyl chains have more than 15 carbon atoms; and optionally monoalkylated alkylbenzene sulfonic acids having C14-C15 alkyl chains or their salts.

[0084] The surfactant in group (B) is selected from the structure ABS(VI)-(VIII).

[0085] (VI) (VII) (VIII)

[0086] in

[0087] R 3 It is a saturated alkyl group containing 14 to 15 carbon atoms;

[0088] R 4 R 5 R 6 R 7 R 8 Independently selected from saturated alkyl groups containing at least two carbon atoms;

[0089] R 4 and R 5The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group has more than 15 carbon atoms.

[0090] R 6 R 7 and R 8 The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group has more than 15 carbon atoms.

[0091] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + .

[0092] In one embodiment of the present invention, the weight ratio of the ABS mixture “Group A” to “Group B” in the ABS composition ranges from 95:5 to 70:30, preferably from 90:10 to 70:30, and more preferably from 85:15 to 75:25.

[0093] In another embodiment, the molar ratio of alkylbenzene sulfonate (VI): [(VII)+(VIII)] in the ABS composition ranges from 0:100 to 20:80.

[0094] In another preferred embodiment, the content of ABS (VII) in the ABS composition is greater than the content of ABS (VIII).

[0095] In a preferred embodiment, at least 50%, preferably at least 90%, of the alkyl chain of the alkylbenzene sulfonic acid or its salt in "Group B" is a straight chain.

[0096] In a preferred embodiment, the SO3M group in ABS(VI) is in the ortho or para position, preferably in the para position.

[0097] To manufacture the ABS mixture of "Group B", an alkylbenzene mixture is first obtained through the following steps:

[0098] (1) Dehydrogenating a mixture of alkanes with a main carbon atom range of 10 to 13 to obtain the corresponding olefins. Typically, the content of compounds with a carbon atom range of 10 to 13 is at least 98%.

[0099] (2) The formed olefin is alkylated with benzene (e.g., using an HF catalyst or a DETAL catalyst). Alkyl transfer may also occur during this step.

[0100] (3) Most of the monoalkylated alkylbenzenes are removed by distillation.

[0101] (4) Distill the fraction rich in higher alkylbenzene and separate this fraction. It is desirable that the boiling point of the first 5% of the fraction is at least 320°C and the boiling point of the remaining 95% is at most 370°C (at atmospheric pressure, according to ASTM D-86).

[0102] (5) The separated alkylbenzene mixture is a liquid at room temperature and exhibits a refractive index of 1.488–1.493 (at 20°C, according to ASTM D-1218).

[0103] The alkylbenzene mixture can then be sulfonated in a falling film reactor with a sulfonating agent (e.g., sulfur trioxide). Optionally, the alkylbenzene sulfonic acid can be neutralized with a base (e.g., sodium hydroxide).

[0104] An alternative synthetic method involves mixing an alkylbenzene compound (which is a starting material for a surfactant from group (A)) with an alkylbenzene (which is a starting material for a surfactant from group (B)). The resulting mixture can then be sulfonated in a falling film reactor with a sulfonating agent (e.g., sulfur trioxide). Alternatively, the alkylbenzene sulfonic acid can be neutralized with a base (e.g., sodium hydroxide).

[0105] ABS compound "Group C"

[0106] The surfactants of group (C) are monoalkylated straight-chain alkylbenzene sulfonic acids or their corresponding salts, wherein the alkyl chain mainly contains 10 to 13 carbon atoms.

[0107] The surfactant in group (C) is selected from the structure ABS (IX).

[0108] (IX)

[0109] in

[0110] R 9 It is a saturated alkyl group containing 10 to 13 carbon atoms;

[0111] M + It is H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + .

[0112] In another embodiment, the ABS(XI) surfactant is selected from ABS(X) and ABS(XI):

[0113] (X) (XI)

[0114] in

[0115] R 10 It is a saturated alkyl group containing 8 to 11 carbon atoms.

[0116] R 11 and R 12 Independently selected from saturated alkyl groups containing 2 to 10 carbon atoms,

[0117] R 11 and R 12 Together they have a total of 9 to 12 carbon atoms;

[0118] M + Independently selected from H + NH4 + Or monovalent cation; preferably H + NH4 + Na + or K + .

[0119] In one embodiment of the invention, the ABS composition comprises an ABS mixture “Group A” and “Group C”, and the weight ratio of the ABS mixture “Group A” to “Group C” ranges from 25:75 to 97.5:2.5, preferably from 50:50 to 97.5:2.5, more preferably from 70:30 to 95:5, and even more preferably from 85:15 to 95:5.

[0120] In another embodiment of the invention, the ABS composition comprises an ABS mixture “Group A”, “Group B” and “Group C”, and the weight ratio of the ABS mixture (“Group A” + “Group B”) to “Group C” ranges from 80:20 to 97.5:2.5, preferably from 85:15 to 97.5:2.5, and more preferably from 85:15 to 95:5.

[0121] In another embodiment of the invention, the weight ratio of ABS(X):ABS(XI) in the ABS composition ranges from 10:90 to 25:75, preferably from 14:86 to 21:79.

[0122] In a preferred embodiment, at least 90%, preferably at least 95%, of the alkyl chain of the alkylbenzene sulfonic acid or its salt in "Group C" is a straight chain.

[0123] In a preferred embodiment, the SO3M group in ABS(IX)-ABS(XI) is independently located at the ortho or para position, preferably at the para position.

[0124] The ABS surfactant in "Group C" can be obtained through the following methods:

[0125] (a) Dehydrogenating a mixture of alkanes with a predominantly 10 to 13 carbon atoms to obtain an olefin, wherein the content of the compound with a carbon atom range of 10 to 13 is at least 98%, or

[0126] (b) A suitable mixture of straight-chain olefins containing mainly C10-C13 carbon atoms obtained by ethylene oligomerization and olefin metathesis.

[0127] The obtained olefins were alkylated with benzene (using an HF or DETAL catalyst), followed by distillation. The first 5% of the monoalkylated benzene mixture obtained by the distillation process had a minimum boiling point of 280°C and the remaining 95% had a maximum boiling point of 310°C (at atmospheric pressure, according to ASTM D-86). The distilled monoalkylated benzene fraction was liquid at room temperature and exhibited a refractive index of 1.481–1.485 (at 20°C, according to ASTM D-1218). The distilled monoalkylated benzene mixture had an average molecular weight ranging from 238 to 243 g / mol.

[0128] The monoalkylbenzene fraction is then sulfonated in a falling film reactor with a sulfonating agent (e.g., sulfur trioxide). Optionally, the alkylbenzene sulfonic acid is neutralized with a base (e.g., sodium hydroxide).

[0129] Other additives

[0130] The initial ABS composition, concentrated blend, or EOR composition may further contain one or more additives selected from the following:

[0131] • A second or additional surfactant that is different from any of the surfactants ABS (I)-(XI),

[0132] •polymer,

[0133] • Solvent,

[0134] • Alkali agent,

[0135] • Biocides,

[0136] •Oxygen scavenger,

[0137] • Free radical scavenger

[0138] • Scale inhibitor, and

[0139] • Corrosion inhibitor.

[0140] The composition may optionally contain a second or additional surfactant other than any of the surfactants ABS (I)-(XI) already described. These second or additional surfactants may include one or more anionic, nonionic, cationic, or amphoteric surfactants that are generally known in the art to effectively reduce the interfacial tension between the composition injected into oil-bearing subsurface formations for oil recovery and residual oil. Cationic surfactants may also be used; however, they are generally less efficient and more expensive. Examples of anionic surfactants include, but are not limited to, aryl ether sulfates, alkyl ether sulfates, alkyl ether sulfonates, alkyl ether hydroxypropyl sulfonates, aryl ether carboxylates, alkyl ether carboxylates, carboxymethylated alkyl polyglucosides, alkylphenol ether sulfonates, alkyl diphenyl ether disulfonates, sulfonated α-olefins, and sulfonated inner olefins. Examples of nonionic surfactants include, but are not limited to, alkoxylated alkylphenols, alkoxylated straight-chain or branched alcohols, and alkyl polyglucosides. Cationic surfactants include, but are not limited to, alkyltrimethylammonium chloride or alkyltrimethylammonium bromide. Amphoteric surfactants include, but are not limited to, betaine, sulfobetaine, amamidopropyl betaine, and amine oxides.

[0141] In one embodiment, the composition of the present invention is free of [Glu1, Asp5]-C15 surfactant. In another embodiment, the composition of the present invention is free of biosurfactants.

[0142] The composition may optionally include a polymer. Examples of polymers include, but are not limited to, high molecular weight acrylic acid-acrylamide copolymers, acrylic acid-acrylamide-diacetone-acrylamide terpolymers, acrylic acid-acrylamide-AMPS terpolymers, partially hydrolyzed polyacrylamide, hydroxyethyl cellulose, carboxymethyl cellulose, polyacrylamide, polyoxyethylene, modified starch, heteropolysaccharides obtained by fermentation of starch-derived sugars, polyvinyl alcohol, polyvinylpyrrolidone, and polystyrene sulfonate.

[0143] The composition may optionally contain a solvent. Examples of suitable solvents include, but are not limited to, alcohols such as lower carbon chain alcohols, such as isopropanol, ethanol, n-propanol, n-butanol, sec-butanol, n-pentanol, sec-pentanol, n-hexanol, and sec-hexanol; alcohol ethers, polyalkylene alcohol ethers such as ethylene glycol monobutyl ether or diethylene glycol monobutyl ether, polyalkylene glycols such as ethylene glycol and propylene glycol, poly(oxyalkylene) glycols such as diethylene glycol, poly(oxyalkylene) glycol ethers, or any mixture thereof.

[0144] The composition may optionally contain an alkaline agent. Examples of suitable alkaline agents include, but are not limited to, sodium metaborate, sodium hydroxide, sodium tetraborate, or sodium carbonate.

[0145] The composition may optionally contain a biocide. Examples of suitable biocides include, but are not limited to, glutaraldehyde and quaternary ammonium compounds with antimicrobial activity, especially those containing long alkyl chains that can be derived from fatty acids. Examples of such quaternary ammonium compounds are those containing at least one of benzylammonium, benzylammonium, methylbenzylammonium, cetalkonium, cetylpyridinium, cetrimonium, cetrimide, dofanium, tetraethylammonium, dialcyldimethylammonium, and domiphen as a quaternary ammonium ion and chloride or bromide as an anion.

[0146] The composition may optionally include an oxygen scavenger. The oxygen scavenger reacts with oxygen that may be present in the aqueous formulation, and thus prevents oxygen from attacking the polymer or polyether groups. Examples of oxygen scavengers include sulfites (e.g., Na₂SO₃), bisulfites, phosphites, hypophosphites, or dithionites.

[0147] The composition may optionally include a scale inhibitor. Examples of suitable scale inhibitors include, but are not limited to, phosphonate compounds (e.g., hexamethylenetetramethylene phosphonate (HMDP), diethylenetriaminepenta(methylphosphonate) (DETPMP), bis(hexamethylene)triaminepenta(methylenephosphonate) (HMTPMP), nitrilotri(methylene)triphosphonate (NTP), pentaethylenehexamineocta(methylenephosphonate) (PEHOMP)) and / or polyphosphonic acids (PPCA).

[0148] Application of EOR composition

[0149] In one embodiment of the invention, an EOR composition was prepared comprising water, surfactant ABS "Group A", optional surfactant "Group B" and / or "Group C", a basic ionic salt, and a second surfactant different from any of surfactants ABS (I)-(IX). The total active surfactant present in the EOR composition is between 0.05 and 2 wt.% relative to the total weight of the EOR composition.

[0150] EOR compositions can be used in oilfields or in enhanced oil recovery (EOR) applications.

[0151] In a preferred embodiment, the EOR composition is used as an EOR surfactant, flow backimprover, wetting agent, dispersant, emulsifier, drilling fluid, fracturing fluid, isolation fluid, cuttings cleaner, wellbore cleaner, and foaming agent for drilling fluid.

[0152] Another embodiment of the present invention is a method for recovering oil from an oil-bearing subsurface formation, the method comprising injecting the above-described EOR composition into one or more injection wells to form a Winsor III type microemulsion, thereby achieving an interfacial tension of < 0.1 mN / m between crude oil and an aqueous surfactant solution and producing oil from one or more production wells. The oil-bearing subsurface formation may contain sandstone or carbonate reservoirs with reservoir temperatures ranging from 15°C to 130°C.

[0153] In a preferred embodiment of the invention, the deposit is a sandstone deposit containing more than 70% by weight sand (quartz and / or feldspar) and may contain up to 25% by weight other minerals selected from kaolinite, montmorillonite, illite, chlorite, and / or pyrite. Preferably, it contains more than 75% by weight sand (quartz and / or feldspar) and may contain up to 20% by weight other minerals selected from kaolinite, montmorillonite, illite, chlorite, and / or pyrite. Particularly preferred is that it contains more than 80% by weight sand (quartz and / or feldspar) and may contain up to 15% by weight other minerals selected from kaolinite, montmorillonite, illite, chlorite, and / or pyrite.

[0154] API specific gravity (American Petroleum Institute specific gravity) is a commonly used unit of density for crude oil in the United States. It is used globally to characterize crude oil and serves as a standard for its quality. API specific gravity is calculated using the following formula based on the relative density p of crude oil at 60°F (15.56°C). rel Calculated:

[0155] API weighting = (141.5 / p) rel ) – 131.5.

[0156] According to the present invention, crude oil from the deposit should have an API value of at least 10°. Preferably, it should have an API value of at least 12°. Particularly preferred is an API value of at least 15°. Very particularly preferred is an API value of at least 20°.

[0157] To carry out the method of the present invention, at least one production well and at least one injection well are drilled in a mineral oil deposit. Typically, the deposit is provided with several injection wells and several production wells. An aqueous formulation of the described water-soluble component is injected into the mineral oil deposit through at least one injection well, and crude oil is extracted from the deposit through at least one production well. Due to the pressure generated by the injected aqueous formulation (referred to as "displacement"), the mineral oil flows toward the production well and is produced via the production well.

[0158] The terms "crude oil" or "mineral oil" in this context certainly do not refer solely to single-phase oil; rather, the term also encompasses common crude oil-water emulsions. It will be apparent to those skilled in the art that mineral oil deposits can also possess a specific temperature distribution. This deposit temperature is based on the area between the injection well and the production well that is covered by an aqueous solution through oil displacement. Methods for determining the temperature distribution of mineral oil deposits are known in principle to those skilled in the art. The temperature distribution is typically determined by a combination of temperature measurements at specific locations within the formation and simulation calculations; these simulations also take into account heat introduced into and removed from the formation.

[0159] Injection of the EOR composition can be carried out using conventional equipment. The composition can be injected into one or more injection wells using a conventional pump. The injection wells are typically lined with cemented steel tubing, which is perforated at the desired point. The formulation enters the mineral oil formation from the injection well through the perforation. Pressure applied by the pump in a manner known in principle is used to set the flow rate of the formulation, and thus also to set the shear stress by which the aqueous formulation enters the formation. The shear stress upon entry into the formation can be calculated by those skilled in the art in a manner known in principle based on the Hagen-Poiseuille law, using the area traversed by the fluid as it enters the formation, the average pore radius, and the volumetric flow velocity. The average permeability of the formation can be obtained in a manner known in principle as described.

[0160] Of course, the higher the volumetric flow rate of the EOR composition injected into the formation, the greater the shear stress. The injection rate can be set by those skilled in the art based on the conditions in the formation.

[0161] The crude oil production method described above using an EOR composition comprising water, surfactant ABS "Group A", and optionally surfactant "Group B" and / or "Group C" can be optionally combined with other methods. For example, polymers or foams can optionally be added for flow control. The polymer can optionally be injected into the deposit together with the surfactant formulation, followed by the injection of the surfactant formulation. It can also be injected only with the surfactant formulation or only after the surfactant formulation. The polymer can be an acrylamide-based copolymer or a biopolymer. The copolymer can, for example, consist particularly of the following units:

[0162] Acrylamide and sodium acrylate

[0163] Acrylamide and sodium acrylate and N-vinylpyrrolidone

[0164] - Acrylamide and sodium acrylate and AMPS (sodium 2-acrylamido-2-methylpropanesulfonate)

[0165] Acrylamide and sodium acrylate and AMPS (sodium 2-acrylamido-2-methylpropanesulfonate) and N-vinylpyrrolidone.

[0166] The copolymer may also additionally contain associating groups. Available copolymers are described in EP 2432807 or WO2014095621. Other available copolymers are described in US 7700702. Example

[0167] In the following examples and comparative examples of the present invention, several alkylbenzene sulfonic acid compositions, concentrated blends, and EOR compositions have been prepared and tested. The methods for preparing and testing these compositions are described below. The experimental results obtained from the tests are collected in Table 1.

[0168] The following examples are presented to illustrate specific embodiments of the invention and should not be construed as limiting the scope of the invention in any way. Alkylation of benzene is described by S. Karimi et al. in the Russian Journal of Applied Chemistry, 2021, Vol. 94, No. 11, pp. 1546-1559.

[0169] Preparation of the ABS composition used in Comparative Example 1 (C1):

[0170] In the first step, AlCl3 was used as a catalyst. The C16 α-olefin (95% linearity, 99% C16 content, 95% α-olefin content) was reacted with benzene. Unreacted feedstock was removed by distillation. Analysis of the resulting alkylbenzene mixture (by proton NMR, carbon NMR, gas chromatography, and mass spectrometry) showed a 36% 2-phenyl isomer content and a 99.7% monoalkylation degree. Benzene content < 100 ppm.

[0171] In the second step, approximately 1.0 equivalent of the obtained C16-Ph is converted with sulfur trioxide in the presence of a nitrogen gas flow at 50°C in a falling film reactor (glass reactor, 1 m in length). The C16-Ph flows from the top to the bottom of the glass reactor, thus forming an organic material membrane. The nitrogen gas flow is regulated to create small ripples on the organic membrane. The nitrogen gas flow contains approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the resulting liquid is collected and stored at 50°C for 2 hours. The sulfonation reaction is quenched by adding 0.3–0.5 wt% water. The obtained materials were analyzed by proton NMR spectroscopy (for the determination of ABS and alkylbenzene content), carbon NMR spectroscopy (for the determination of ABS and alkylbenzene content), gas chromatography and HPLC (both for the determination of structure ratio), ion chromatography (for the determination of sulfuric acid content), hydantoin titration (for the determination of anionic surfactant content), and Karl Fischer analysis (for the determination of water content).

[0172] The obtained composition, C1:

[0173]

[0174] Preparation of the ABS composition used in Example 2 of the present invention:

[0175] In the first step, HF was used as a catalyst. A C16 α-olefin (95% linearity, 99% C16 content, 95% α-olefin content) was reacted with benzene. Unreacted feedstock was removed by distillation, retaining the desired alkylbenzene mixture. Analysis of the obtained alkylbenzene mixture (by proton NMR, carbon NMR, gas chromatography, and mass spectrometry) showed a 17% 2-phenyl isomer content and a 98.7% degree of monoalkylation. Benzene content < 100 ppm.

[0176] In the second step, approximately 1.0 equivalent of the obtained C16-Ph was converted with sulfur trioxide in the presence of a nitrogen stream at 50°C in a falling film reactor (glass reactor, 1 m in length). The C16-Ph flowed from the top to the bottom of the glass reactor, thus forming an organic material film. The nitrogen stream was regulated to create small ripples on the organic film. The nitrogen stream contained approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the obtained liquid was collected and stored at 50°C for 2 hours. The sulfonation reaction was quenched by adding 0.3–0.5 wt% water. The obtained material was analyzed by proton NMR spectroscopy (for ABS and alkylbenzene content determination), carbon NMR spectroscopy (for ABS and alkylbenzene content determination), gas chromatography and HPLC (both for structure ratio determination), ion chromatography (for sulfuric acid content determination), hydantoin titration (for anionic surfactant content determination), and Karl Fischer analysis (for water content determination).

[0177] The obtained composition, Example 2:

[0178]

[0179] Preparation of the ABS composition used in Comparative Example 3 (C3):

[0180] In the first step, a so-called heavy alkylbenzene (HAB) fraction produced from detergents is used.

[0181] The heavy alkylbenzene fraction is obtained as follows: A fraction of alkane containing primarily 10 to 13 carbon atoms is partially dehydrogenated, and the resulting olefin (primarily mono-olefin and primarily straight-chain) is reacted with benzene using HF as a catalyst. The alkylbenzene mixture is purified from the unreacted feedstock. The C10-C13 monoalkylated alkylbenzene fraction is then removed by distillation. This monoalkylated alkylbenzene fraction contains primarily 10 to 13 carbon atoms in the alkyl chain, has an average molecular weight starting from 242 g / mol, a 15% 2-phenyl isomer content, and a boiling range of 288°C (for the first 5% of the fraction) to 304°C (for the 95% of the fraction) at 1 atm absolute pressure.

[0182] After removing the C10-C13 monoalkylbenzene fraction, the so-called heavy alkylbenzene fraction (HAB fraction) remains. From this HAB fraction, components with lower boiling points are separated by distillation. The desired fraction characteristics are as follows: boiling point range of 329°C (for the first 5%) to 350°C (for the 95%) at 1 atm absolute pressure. The obtained alkylbenzene mixture was analyzed (via proton NMR spectroscopy, carbon NMR spectroscopy, gas chromatography, and mass spectrometry). The content of monoalkylbenzenes containing 14 to 15 carbon atoms in the alkyl group was about 10%. The total number of carbon atoms in the alkyl groups of dialkyl and trialkylbenzenes ranged from 12 to 18, while the single alkyl group of polyalkylbenzenes did not contain more than 15 carbon atoms.

[0183] In the second step, the obtained fraction is sulfonated. In a falling film reactor (glass reactor, 1 m in length), at 50°C in the presence of a nitrogen stream, approximately 1.03 equivalents of sulfur trioxide are used to convert 1.0 equivalent of the obtained alkylbenzene. The alkylbenzene flows from the top to the bottom of the glass reactor, thus forming an organic material film. The nitrogen stream is regulated to create small ripples on the organic film. The nitrogen stream contains approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the obtained liquid is collected and stored at 50°C for 2 hours. The sulfonation reaction is quenched by adding 0.3–0.5 wt% water. The obtained material is analyzed by proton NMR spectroscopy (for ABS and alkylbenzene content determination), carbon NMR spectroscopy (for ABS and alkylbenzene content determination), gas chromatography and HPLC (both for structure ratio determination), ion chromatography (for sulfuric acid content determination), hydantoin titration (for anionic surfactant content determination), and Karl Fischer analysis (for water content determination).

[0184] The obtained composition, C3:

[0185]

[0186] 1 Error range ± 5

[0187] 2 According to ASTM D-86

[0188] Preparation of the ABS composition used in Comparative Example 4 (C4):

[0189] In a 250 ml round-bottom glass flask equipped with a stirrer, 100 g of ABS mixture was prepared by mixing 45 g of ABS composition from C1 and 55 g of ABS composition from C3 at 50°C. The two ABS compositions were added to the flask and stirred at 50°C for 1 hour to obtain a homogeneous mixture.

[0190] The obtained composition, C4:

[0191]

[0192] 1 Error range ± 5

[0193] Preparation of the ABS composition used in Example 5 of the present invention:

[0194] In the first step, a mixture of alkylbenzenes is prepared.

[0195] use HF as a catalyst The C16 α-olefin (95% linearity, 99% C16 content, 95% α-olefin content) was reacted with benzene. Unreacted feedstock was removed by distillation. Analysis of the resulting alkylbenzene mixture (by proton NMR, carbon NMR, gas chromatography, and mass spectrometry) showed a 17% 2-phenyl isomer content and a 97.7% monoalkylation degree. The benzene content was < 100 ppm. 800 g of this C16 alkylbenzene was mixed with 200 g of the alkylbenzene mixture obtained during the first step of Example C3 (this means the alkylbenzene mixture obtained prior to the sulfonation step in C3) in a glass vessel equipped with a stirrer at 50°C.

[0196] In the second step, an 80:20 mixture of alkylbenzenes (80 wt% C16-alkylbenzenes and 20 wt% C12-C18 alkylbenzenes) is sulfonated.

[0197] In a falling film reactor (glass reactor, 1 m in length), at 50°C in the presence of a nitrogen stream, a 1.0 equivalent of an 80:20 alkylbenzene mixture was reacted with approximately 1.03 equivalents of sulfur trioxide. The alkylbenzene flowed from the top to the bottom of the glass reactor, thus forming an organic material film. The nitrogen stream was regulated to create small ripples on the organic film. The nitrogen stream contained approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the resulting liquid was collected and stored at 50°C for 2 hours. The sulfonation reaction was quenched by adding 0.3–0.5 wt% water. The resulting material was analyzed by proton NMR spectroscopy (for ABS and alkylbenzene content determination), carbon NMR spectroscopy (for ABS and alkylbenzene content determination), gas chromatography and HPLC (both for structure ratio determination), ion chromatography (for sulfuric acid content determination), hydantoin titration (for anionic surfactant content determination), and Karl Fischer analysis (for water content determination).

[0198] The obtained composition, Example 5:

[0199]

[0200] 1 Error range ± 5

[0201] Preparation of the ABS composition used in Example 6 of the present invention:

[0202] An ABS composition containing detergent surfactant C10-C13-Ph-SO3H is obtained in the following manner:

[0203] In the first step, a fraction of alkane containing primarily 10 to 13 carbon atoms is partially dehydrogenated, and HF is used as a catalyst to react the resulting olefin (primarily a mono-olefin and primarily linear) with benzene. Unreacted feedstock is removed by distillation. Then, a fraction of C10-C13 monoalkylated alkylbenzenes is removed by distillation. This monoalkylated alkylbenzene fraction contains primarily 10 to 13 carbon atoms in its alkyl chain (average 11.6 carbon atoms), has an average molecular weight starting at 241 g / mol, a 15% 2-phenyl isomer content, and a boiling range of 288°C (for the first 5% of the fraction) to 304°C (for the 95% of the fraction) at 1 atm absolute pressure.

[0204] In the second step, the obtained C10-C13 ABS mixture is sulfonated. In a falling film reactor (glass reactor, 1 m in length), at 50°C in the presence of a nitrogen stream, approximately 1.03 equivalents of sulfur trioxide are used to convert 1.0 equivalent of the obtained alkylbenzene. The alkylbenzene flows from the top to the bottom of the glass reactor, thereby forming an organic material membrane. The nitrogen stream is regulated in a manner that creates small ripples on the organic membrane. The nitrogen stream contains approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the resulting liquid is collected and stored at 50°C for 2 hours. The sulfonation reaction is quenched by adding 0.3-0.5 wt.% water. The obtained materials were analyzed by proton NMR spectroscopy (for the determination of ABS and alkylbenzene content), carbon NMR spectroscopy (for the determination of ABS and alkylbenzene content), gas chromatography and HPLC (both for the determination of structure ratio), ion chromatography (for the determination of sulfuric acid content), hydantoin titration (for the determination of anionic surfactant content), and Karl Fischer analysis (for the determination of water content).

[0205] Finally, a 100 g ABS mixture was prepared in a 250 ml round-bottom glass flask equipped with a stirrer at 50°C by mixing the ABS composition (92.5 g) from Example 5 with the prepared ABS composition containing the detergent surfactant C10-C13-Ph-SO3H (7.5 g). The two ABS compositions were added to the flask and stirred at 50°C for 1 hour to obtain a homogeneous mixture. The obtained material was analyzed by proton NMR spectroscopy (for the determination of ABS and alkylbenzene content), carbon NMR spectroscopy (for the determination of ABS and alkylbenzene content), gas chromatography and HPLC (both for the determination of structure ratios), ion chromatography (for the determination of sulfuric acid content), hydantoin titration (for the determination of anionic surfactant content), and Karl Fischer analysis (for the determination of water content).

[0206] The obtained composition, Example 6:

[0207]

[0208] 1 Error range ± 5

[0209] Preparation of the ABS composition used in Example 7 of the present invention:

[0210] An ABS composition containing detergent surfactant C10-C13-Ph-SO3H is obtained in the following manner:

[0211] In the first step, a fraction of alkane containing primarily 10 to 13 carbon atoms is partially dehydrogenated, and HF is used as a catalyst to react the resulting olefin (primarily a mono-olefin and primarily linear) with benzene. Unreacted feedstock is removed by distillation. Then, a fraction of C10-C13 monoalkylated alkylbenzenes is removed by distillation. This monoalkylated alkylbenzene fraction contains primarily 10 to 13 carbon atoms in its alkyl chain (average 11.6 carbon atoms), has an average molecular weight starting at 241 g / mol, a 15% 2-phenyl isomer content, and a boiling range of 288°C (for the first 5% of the fraction) to 304°C (for the 95% of the fraction) at 1 atm absolute pressure.

[0212] In the second step, the obtained C10-C13 ABS mixture is sulfonated. In a falling film reactor (glass reactor, 1 m in length), at 50°C in the presence of a nitrogen stream, approximately 1.03 equivalents of sulfur trioxide are used to convert 1.0 equivalent of the obtained alkylbenzene. The alkylbenzene flows from the top to the bottom of the glass reactor, thereby forming an organic material membrane. The nitrogen stream is regulated in a manner that creates small ripples on the organic membrane. The nitrogen stream contains approximately 1.03 equivalents of gaseous sulfur trioxide. At the bottom of the reactor, the resulting liquid is collected and stored at 50°C for 2 hours. The sulfonation reaction is quenched by adding 0.3-0.5 wt.% water. The obtained materials were analyzed by proton NMR spectroscopy (for the determination of ABS and alkylbenzene content), carbon NMR spectroscopy (for the determination of ABS and alkylbenzene content), gas chromatography and HPLC (both for the determination of structure ratio), ion chromatography (for the determination of sulfuric acid content), hydantoin titration (for the determination of anionic surfactant content), and Karl Fischer analysis (for the determination of water content).

[0213] Finally, a 100 g ABS mixture was prepared in a 250 ml round-bottom glass flask equipped with a stirrer at 50°C by mixing the ABS composition (92.5 g) from Example 2 with the prepared ABS composition containing the detergent surfactant C10-C13-Ph-SO3H (7.5 g). The two ABS were added to the flask, stirred at 50°C for 1 hour, and a homogeneous mixture was obtained. The obtained material was analyzed by proton NMR spectroscopy (for the determination of ABS and alkylbenzene content), carbon NMR spectroscopy (for the determination of ABS and alkylbenzene content), gas chromatography and HPLC (both for the determination of structure ratios), ion chromatography (for the determination of sulfuric acid content), hydantoin titration (for the determination of anionic surfactant content), and Karl Fischer analysis (for the determination of water content).

[0214] The obtained composition, Example 7:

[0215]

[0216] 1 Error range ± 5

[0217] Preparation of concentrated blends

[0218] To prepare a concentrated blend containing a high content of active surfactant and a low water content, alkylbenzene sulfonic acid prepared in Comparative Examples 1, 3, and 4, as well as Examples 2, 5, 6, and 7 of the present invention, was subjected to TSP-(PO) treatment. 35 -(EO) 20Neutralization with 50 wt.% NaOH in water was carried out in the presence of SO4NH4 (a polyalkoxylated surfactant). The resulting concentrated blend had a pH of at least 7.5.

[0219] TSP-(PO) 35 -(EO) 20 Preparation of -SO4NH4:

[0220] Styrelated phenol (80% tristyrylphenol, 15% stilbenelphenol, and 5% monostyrylphenol) was first propoxylated with 35 equivalents of propylene oxide and then ethoxylated with 20 equivalents of ethylene oxide using KOH catalysis at 130°C. It was then sulfonated with aminosulfonic acid at 95°C in the presence of a catalytic amount of urea. 1 ¹H-NMR yielded 98% sulfonation. The obtained TSP-(PO) 35 -(EO) 20 -SO4NH4 has an active content of 98%, a pour point of <20°C, and a viscosity of 9000-14000 mPas at 25°C.

[0221] The active ABS surfactant (in acidic form) and TSP-(PO) are used in each concentrated blend. 35 -(EO) 20 The precise weight ratios of SO4NH4 and 50 wt.% NaOH aqueous solution are indicated in Table 1. In all cases, the TSP-(PO) content in the concentrated blend is... 35 -(EO) 20 The weight ratio of SO4NH4 to reactive ABS (in acidic form) is approximately 1.5:1. This is equivalent to TSP-(PO) 35 -(EO) 20 The weight ratio of SO4NH4 to active ABS (in salt form, i.e., due to the neutralization of ABS with sodium hydroxide) is 1.5:1.056.

[0222] Preparation of EOR Composition

[0223] To prepare the EOR composition, the concentrated blend was dissolved in brine until the following desired surfactant concentration was obtained: 2556 ppm of active surfactant (1500 ppm of TSP-(PO)). 35 -(EO) 20 -SO4NH4 + 1056 ppm of active ABS (in salt form)

[0224] The brine used for appearance / solubility testing is made of water, 0.45% NaCl, 0.01% KCl, 0.1% NaHCO3, 0.05% Na2SO4, and 2.75% Na2CO3.

[0225] The saline solution used for IFT testing is made of water, 0.45% NaCl, 0.01% KCl, 0.1% NaHCO3, 0.05% Na2SO4, and 2.5% Na2CO3.

[0226] Viscosity measurement

[0227] The viscosity of the alkylbenzene sulfonic acid composition and the concentrated blend was measured. AntonParr viscometer with a double-gap geometry was used. The results are shown in Table 1.

[0228] At 25°C and 10 s -1 A viscosity of less than 5000 mPas indicates that the material is pumpable.

[0229] Pour point measurement

[0230] The pour points of the alkylbenzene sulfonic acid compositions and concentrated blends were measured according to ASTM D7346. The results are shown in Table 1.

[0231] A low pour point indicates that the material can still flow at lower temperatures and is pumpable.

[0232] Evaluation of the appearance of the EOR composition at 65°C

[0233] The reaction of alkylbenzene sulfonates with TSP-(PO) at 65°C was investigated. 35 -(EO) 20 The solubility of the combination of -SO4NH4 in the presence of Na2CO3.

[0234] In order to use alkylbenzene sulfonic acids in EOR applications, they are neutralized with, for example, Na2CO3 or NaOH to obtain the corresponding salts.

[0235] The EOR composition will contain at least an alkylbenzene sulfonate, any impurities from the ABS preparation steps (e.g., sulfonic acid), any residual Na₂CO₃ or NaOH from the neutralization step, and (if desired) a second surfactant. For a successful EOR process, it is important that the EOR composition is clear, homogeneous, and stable. If the EOR composition is turbid and prone to precipitation, for example due to the formation of sodium sulfate (from residual sulfonic acid and Na₂CO₃ or NaOH) or calcium sulfate (from residual sulfonic acid contacting formation water containing divalent cations such as calcium cations), there is a risk that porous reservoirs may be blocked and the oil recovery process will be unsuccessful.

[0236] Evaluation was conducted visually.

[0237] Interfacial tension (IFT) measurement of EOR composition and crude oil

[0238] The interaction between 10 vol.% crude oil (from northwestern India, rich in alkanes) and a 90 vol% EOR composition was investigated. Using an EOR composition containing only 2.5% Na₂CO₃ ensured optimal solubility and phase behavior. Winsor III type microemulsions were formed after storage under optimal conditions for several days or weeks without stirring. Ultra-low interfacial tensions, typically < 0.01 mN / m, were achieved in the Winsor III type microemulsions. SP was obtained from phase behavior testing. Interfacial tension can be calculated using the Huh equation. Measurements were performed at 65°C.

[0239]

[0240] Comments on the experimental results shown in Table 1:

[0241] There are two main methods to obtain EOR compositions containing 0.05 to 2 wt.% surfactants (including at least ABS surfactants) ready for use at the reservoir site. It should be noted that for EOR operations, alkylbenzene sulfonic acids should be neutralized with, for example, Na₂CO₃ or NaOH to obtain the corresponding sodium salts, and these should be reacted with at least a second surfactant (e.g., based on polyalkoxylates, such as TSP-(PO)). 35 -(EO) 20 -SO4NH4) mixture.

[0242] The first option is to use an acidic ABS composition (M + = H + The acidic ABS composition is transported from the manufacturing site to the reservoir location or nearby and undergoes a neutralization step, and (if necessary) is mixed there with a second or additional surfactant. For this option to be successful and efficient, it is desirable that the acidic ABS composition be easy to transport and handle. This is tested in columns 3 and 4 of Table 1 and discussed below.

[0243] The second option is to directly deliver a concentrated surfactant blend containing neutralized ABS and (if necessary) a second or additional surfactant at a high activity level to the reservoir site or nearby. The concentrated surfactant blend can then be dissolved there to obtain a ready-to-use EOR composition. For this option to be successful and efficient, the concentrated blend is expected to have optimal transport and handling characteristics. In other words, it is highly desirable that the concentrated blend is flowable at 20°C (pour point < 20°C) and has a sufficiently low viscosity at, for example, 65°C, to allow for smooth pumping of the material (sulfonated surfactants are stable at at least 60°C–65°C, depending on pH). This is tested in columns 6 and 7 of Table 1 and discussed below.

[0244] Furthermore, the suitability of the EOR composition of this invention for successful crude oil recovery in EOR operations is examined. For this purpose, the EOR composition should have a clear appearance and be homogeneous and stable, as turbid solutions can lead to blockage of porous reservoirs. Moreover, it is highly desirable to add the EOR composition to subsurface formations to produce Winsor Type III emulsions that achieve ultra-low IFT (i.e., < 0.01 mN / m) between water and oil. This is tested in columns 8 and 9 of Table 1 and discussed below.

[0245] Option 1 – Transport individual components:

[0246] Column 3 of Table 1 shows the acidic ABS composition (M) of the present invention with high activity content. + = H + It is a liquid and low-viscosity substance at room temperature. The tested compositions had an active content higher than 90 wt.%, and they were soluble in water at 25°C and 10 s⁻¹. -1 The viscosity shown is well below 5000 mPas. This demonstrates that acidic ABS compositions with high active content can be transported to other locations (e.g., remote reservoirs) in a highly efficient manner, in other words, compared to transporting diluted, neutralized aqueous solutions of ABS (e.g., M...) containing approximately 10-20 wt.% active material. + = Na + Compared to other methods, transporting these ABS compositions to other locations (such as remote storage facilities) requires less storage capacity (e.g., fewer trucks) and therefore less energy.

[0247] Once the ABS composition (M + = H +The acidic ABS composition has reached a location near the reservoir and should be neutralized, for example, with an alkali (such as Na₂CO₃ or NaOH) to obtain the corresponding sodium salt before being introduced into the underground well formation. It is important to note that many oil and gas recovery operations are carried out in winter or at locations with very low ambient temperatures. To facilitate the operation of the acidic ABS composition and its neutralization step and to reduce heating requirements, it is highly desirable that the acidic ABS composition remain flowable and pumpable at very low temperatures, i.e., with a low pour point. Column 4 of Table 1 clearly shows that the ABS compositions of the present invention have much lower pour points than the comparative compositions. Examples 2, 5, 6, and 7 of the present invention show pour points between -30°C and -33°C, while the comparative examples show pour points as high as -9°C (C₁).

[0248] The second option – transporting concentrated surfactant blends:

[0249] If concentrated surfactant blends are to be delivered directly to or near the reservoir, it is desirable that the blends have low water content, high activity content, and be flowable at 20°C (pour point < 20°C) to reduce the energy costs of transporting and storing such blends. Additionally, it is desirable that the viscosity at, for example, 65°C is sufficiently low to allow for smooth pumping of the material.

[0250] To obtain high activity and low water content, alkylbenzene sulfonic acid is incorporated into the previously described TSP-(PO) process. 35 -(EO) 20 Neutralization was performed in the presence of SO4NH4 using a 50 wt% NaOH aqueous solution.

[0251] As shown in columns 6 and 7 of Table 1, the concentrated blends of the present invention have a desired pour point of <20°C and a viscosity of approximately 1000-650 mPas at 65°C. This means the material can be pumped well. In contrast, comparative examples C1 and C4 show undesirable waxy materials with pour points >40°C. In these cases, unwanted foam formation was also observed (due to some ammonia release), and higher amounts of NaOH solution were required to achieve complete neutralization of the alkylbenzene sulfonic acid.

[0252] Suitability of EOR compositions for EOR applications:

[0253] The effects of neutralized alkylbenzene sulfonic acid on TSP-(PO) were investigated. 35 -(EO) 20The solubility of the SO4NH4 combination at 65°C in the presence of Na2CO3. Column 8 in Table 1 shows the appearance of the aqueous surfactant solution (i.e., the EOR composition) at 65°C. Except for Comparative Example 3, all examples showed clear, stable, and homogeneous solutions, indicating sufficient solubility. The ABS compound in Group B, which lacked Group A ABS compound, was insufficiently soluble and therefore formed a turbid solution. This is highly undesirable in oil recovery operations, as turbid solutions can lead to blockage of porous reservoirs. Turbid solutions should be avoided.

[0254] The interaction with crude oil was investigated. In these tests, brine with a low Na₂CO₃ content was selected to match solubility and optimal phase behavior. It is expected that adding EOR compositions to subsurface formations will produce Winsor Type III emulsions that achieve ultra-low IFT (i.e., < 0.01 mN / m) between water and oil.

[0255] The formation of Winsor III type microemulsions is indicated by the formation of golden streaks when crude oil is mixed with an aqueous surfactant solution under optimal conditions. Once the Winsor III type microemulsion is obtained, SP is measured. The interfacial tension was calculated using the Huh equation. Column 9 of Table 1 shows that the EOR composition of the present invention successfully achieved an ultra-low interfacial tension of < 0.01 mN / m.

[0256] Comparative Example C1 did not produce a Winsor III type microemulsion and only achieved a high IFT. The EOR composition of Comparative Example 3 (C3) was not tested because it did not provide sufficient solubility.

[0257] Therefore, the experimental results in Table 1 show that Examples 2, 5, 6, and 7 of the present invention provide the desired match between operation (low pour point and low viscosity), solubility, and interfacial tension relative to crude oil. In contrast, the single compounds in Comparative Examples C1, C3, and C4 did not provide the desired characteristics and failed in at least one aspect.

[0258] Embodiments of the present invention:

[0259] 1. A composition comprising alkylbenzene sulfonate ABS(I) and ABS(II).

[0260] (I) (II)

[0261] in

[0262] R 1 and R 2 Independently selected from saturated alkyl groups containing 2 to 13 carbon atoms;

[0263] R 1 and R 2 Together they have a total of 15 carbon atoms;

[0264] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;

[0265] The molar ratio of ABS(I):ABS(II) ranges from 10:90 to 30:70;

[0266] Furthermore, the composition comprises at least one additional alkylbenzene sulfonate molecule selected from ABS(III), ABS(IV), ABS(V), and mixtures thereof.

[0267] (III) (IV) (V)

[0268] in

[0269] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;and

[0270] The molar ratio of these alkylbenzene sulfonates [(I)+(II)] : [(III)+(IV)+(V)] ranges from 90 : 10 to 99.9 : 0.1;

[0271] These alkylbenzene sulfonates (I)-(V) can be collectively referred to as the ABS mixture "Group A".

[0272] 2. In a preferred embodiment of the invention, the composition further comprises other alkylbenzene sulfonate molecules different from the ABS mixture “Group A”, and the amount of the ABS mixture “Group A” is based on the total weight of all alkylbenzene sulfonate molecules present in the composition, which is at least 50 wt.%, preferably at least 60 wt.%, and more preferably at least 70 wt.%.

[0273] 3. In a preferred embodiment of the invention, the composition comprises at least one additional alkylbenzene sulfonate molecule selected from ABS(VI), ABS(VII), ABS(VIII), and mixtures thereof.

[0274] (VI) (VII) (VIII)

[0275] in

[0276] R 3 It is a saturated alkyl group containing 14 to 15 carbon atoms;

[0277] R 4 R 5 R 6 R 7 R 8 Independently selected from saturated alkyl groups containing at least two carbon atoms;

[0278] R 4 and R 5 The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group contains more than 15 carbon atoms.

[0279] R 6 R 7 and R 8 The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group contains more than 15 carbon atoms.

[0280] M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;

[0281] These alkylbenzene sulfonates (VI)-(VIII) can be collectively referred to as ABS mixture "Group B"; and

[0282] The weight ratio of the ABS mixture “Group A” to “Group B” ranges from 95:5 to 70:30, preferably from 90:10 to 70:30, and more preferably from 85:15 to 75:25.

[0283] 4. In a preferred embodiment of the invention, the molar ratio of these alkylbenzene sulfonates (VI): [(VII)+(VIII)] ranges from 0:100 to 20:80.

[0284] 5. In a preferred embodiment of the invention, the composition comprises

[0285] ABS(IX)

[0286] (IX)

[0287] in

[0288] R 9 It is a saturated alkyl group containing 10 to 13 carbon atoms;

[0289] M + It is H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;and

[0290] These alkylbenzene sulfonates (IX) may be referred to as “Group C” of the ABS mixture, and the weight ratio of “Group A” to “Group C” of the ABS mixture ranges from 25:75 to 97.5:2.5, preferably from 50:50 to 97.5:2.5, more preferably from 70:30 to 95:5, and even more preferably from 85:15 to 95:5.

[0291] 6. In a preferred embodiment of the invention, the composition further comprises an ABS mixture “Group C” as defined above, wherein the weight ratio of the ABS mixture (“Group A” + “Group B”) to “Group C” ranges from 80:20 to 97.5:2.5, preferably from 85:15 to 97.5:2.5, and more preferably from 85:15 to 95:5.

[0292] 7. In a preferred embodiment of the present invention, the ABS(IX) is selected from ABS(X) and ABS(XI).

[0293] (X) (XI)

[0294] in

[0295] R 10 It is a saturated alkyl group containing 8 to 11 carbon atoms.

[0296] R 11 and R 12 Independently selected from saturated alkyl groups containing 2 to 10 carbon atoms,

[0297] R 11 and R 12Together they have a total of 9 to 12 carbon atoms;

[0298] M + Independently selected from H + NH4 + Or monovalent cation; preferably H + NH4 + Na + or K + ,and

[0299] The weight ratio of ABS(X):ABS(XI) ranges from 10:90 to 25:75, preferably from 14:86 to 21:79.

[0300] 8. In a preferred embodiment of the invention, any one of the alkyl chains in ABS (I)-(V) and (IX)-(XI) is at least 90 wt.% straight chain, preferably at least 95 wt.% straight chain.

[0301] 9. A concentrated blend comprising an ABS composition according to any one of the above embodiments, an alkaline ionic salt, and a second surfactant different from any one of ABS (I)-(XI).

[0302] 10. In a preferred embodiment of the invention, the second surfactant in the concentrated blend is a polyalkoxylated surfactant, preferably a tristyrylphenol alkoxysulfate surfactant, more preferably TSP-(PO) 35 -(EO) 20 -SO4NH4.

[0303] 11. In a preferred embodiment of the invention, the weight ratio of the second surfactant in the concentrated blend to the ABS composition in acidic form is between 1:1 and 2:1, preferably between 1.4:1 and 1.6:1.

[0304] 12. An EOR composition comprising an ABS composition according to any one of the above embodiments, an alkaline ionic salt, and an additional surfactant other than any of ABS (I)-(XI), wherein the total amount of all surfactants present in the EOR composition is between 0.05 and 2 wt.% relative to the total weight of the EOR composition.

[0305] 13. Use of the EOR composition according to the above embodiments in oilfield or enhanced oil recovery (EOR) applications.

[0306] 14. In a preferred embodiment of the invention, the oilfield or EOR application is selected from the group consisting of: EOR surfactants, flowback improvers, wetting agents, dispersants, emulsifiers, drilling fluids, fracturing fluids, isolation fluids, cuttings cleaners, wellbore cleaners, and foaming agents for drilling fluids.

[0307] 15. A method for recovering oil from an oil-bearing subsurface formation, the method comprising injecting an EOR composition according to the above embodiments into one or more injection wells to form a Winsor III type microemulsion, thereby achieving an interfacial tension of < 0.1 mN / m between crude oil and an aqueous surfactant solution and producing oil from one or more production wells.

[0308] 16. In a preferred embodiment of the present invention, the oil-bearing underground formation contains sandstone or carbonate reservoirs with a reservoir temperature of 15°C to 130°C.

Claims

1. A composition comprising alkylbenzene sulfonate ABS(I) and ABS(II). (AND) (II) in R 1 and R 2 Independently selected from saturated alkyl groups containing 2 to 13 carbon atoms; R 1 and R 2 Together they have a total of 15 carbon atoms; M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ; The molar ratio of ABS(I):ABS(II) ranges from 10:90 to 30:

70.

2. The composition according to claim 1, wherein, The composition contains at least one additional alkylbenzene sulfonate molecule selected from ABS(III), ABS(IV), ABS(V), and mixtures thereof. (III) (IV) (V) in M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ;and The molar ratio of these alkylbenzene sulfonates [(I)+(II)] : [(III)+(IV)+(V)] ranges from 90 : 10 to 99.9 : 0.1; These alkylbenzene sulfonates (I)-(V) can be collectively referred to as ABS mixture "Group A".

3. The composition according to claim 2, wherein, The composition further comprises other alkylbenzene sulfonate molecules different from the ABS mixture "Group A", and the amount of the ABS mixture "Group A" is based on the total weight of all alkylbenzene sulfonate molecules present in the composition, which is at least 50 wt.%, preferably at least 60 wt.%, and more preferably at least 70 wt.%.

4. The composition according to claim 2 or 3, wherein, The composition contains at least one additional alkylbenzene sulfonate molecule selected from ABS(VI), ABS(VII), ABS(VIII), and mixtures thereof. (VI) (VII) (VIII) in R 3 It is a saturated alkyl group containing 14 to 15 carbon atoms; R 4 R 5 R 6 R 7 R 8 Independently selected from saturated alkyl groups containing at least two carbon atoms; R 4 and R 5 The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group contains more than 15 carbon atoms. R 6 R 7 and R 8 The total number of carbon atoms in a single alkyl group ranges from 10 to 20, but no single alkyl group contains more than 15 carbon atoms. M + Independently selected from H + NH4 + Or a monovalent cation, preferably H + NH4 + Na + or K + ; These alkylbenzene sulfonates (VI)-(VIII) can be collectively referred to as ABS mixture "Group B"; and The weight ratio of the ABS mixture "Group A" to "Group B" ranges from 95:5 to 70:30, preferably from 90:10 to 70:30, and more preferably from 85:15 to 75:

25.

5. The composition according to claim 4, wherein, The molar ratio of these alkylbenzene sulfonates (VI): [(VII)+(VIII)] ranges from 0:100 to 20:

80.

6. The composition according to any one of claims 2 to 5, wherein, The composition contains ABS(IX) (IX) in R9 is a saturated alkyl group containing 10 to 13 carbon atoms; M+ is H+, NH4+, or a monovalent cation, preferably H+, NH4+, Na+, or K+; and These alkylbenzene sulfonates (IX) may be referred to as ABS mixture "Group C" and the weight ratio of ABS mixture "Group A" to "Group C" ranges from 25:75 to 97.5:2.5, preferably 50:50 to 97.5:2.5, more preferably 70:30 to 95:5, and even more preferably 85:15 to 95:

5.

7. The composition according to any one of claims 4 or 5, wherein, The composition further comprises an ABS mixture "Group C" as defined above, and the weight ratio of the ABS mixture ("Group A" + "Group B") to "Group C" ranges from 80:20 to 97.5:2.5, preferably from 85:15 to 97.5:2.5, and more preferably from 85:15 to 95:

5.

8. The composition according to any one of claims 6 or 7, wherein, This ABS(IX) is selected from ABS(X) and ABS(XI). (X) (11) in R 10 It is a saturated alkyl group containing 8 to 11 carbon atoms. R 11 and R 12 Independently selected from saturated alkyl groups containing 2 to 10 carbon atoms, R 11 and R 12 Together they have a total of 9 to 12 carbon atoms; M + Independently selected from H + NH4 + Or monovalent cation; preferably H + NH4 + Na + or K + ,and The weight ratio of ABS(X):ABS(XI) ranges from 10:90 to 25:75, preferably from 14:86 to 21:

79.

9. The composition according to any one of the preceding claims, wherein, Either of the alkyl chains in ABS (I)-(V) and (IX)-(XI) is at least 90% straight-chain.

10. The composition according to any one of the preceding claims, wherein, The composition additionally contains a basic ionic salt and a second surfactant.

11. The composition according to claim 9, wherein, The second surfactant is a polyalkoxylated surfactant, preferably a tristyrylphenol alkoxysulfate surfactant, more preferably TSP-(PO) surfactant. 35 -(EO) 20 -SO4NH4.

12. The composition according to any one of claims 9 or 10, wherein, The weight ratio of the second surfactant to the acidic ABS composition is between 1:1 and 2:1, preferably between 1.4:1 and 1.6:

1.

13. An EOR composition comprising an ABS composition according to any one of claims 1 to 8, an alkaline ionic salt, and an additional surfactant different from any one of the ABS (I)-(XI) described in any one of claims 1 to 9, wherein the total amount of all surfactants present in the EOR composition is between 0.05 and 2 wt.% relative to the total weight of the EOR composition.

14. Use of the EOR composition according to claim 12 in oilfield or enhanced oil recovery (EOR) applications.

15. The use according to claim 14, wherein, The oilfield or EOR application is selected from the group consisting of: EOR surfactants, flowback improvers, wetting agents, dispersants, emulsifiers, drilling fluids, fracturing fluids, isolation fluids, drill cuttings cleaners, wellbore cleaners, and foaming agents for drilling fluids.

16. A method for recovering oil from an oil-bearing subsurface formation, the method comprising injecting the composition of claim 13 into one or more injection wells to form a Winsor III type microemulsion, thereby achieving an interfacial tension of < 0.1 mN / m between crude oil and an aqueous surfactant solution and producing oil from one or more production wells.

17. The method for oil recovery according to claim 16, wherein, The oil-bearing underground formation contains sandstone or carbonate reservoirs with reservoir temperatures ranging from 15°C to 130°C.

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