Foam control with hydrophilically-modified polyorganosiloxane

Abstract

A hydrophilically-modified polyorganosiloxane with a hydrophilic moiety derived from a hydroxy-functional lactone is useful as a foam control agent for crude oil. A composition and method that are alternatives to PFAS (perfluoroalkyl substances) are described herein using the hydrophilically-modified polyorganosiloxane in oil and gas applications.

Description

LOAM CONTROL WITH HYDR0PHILICALLY-M0DIF1ED POLYORGAN OS ILOXANECROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No.63 / 760,814 filed on February 20, 2025, under 35 U.S.C. §119 (e). U.S. Provisional Patent Application Serial No. 63 / 760,814 is hereby incorporated by reference.FIELD

[0002] A foam control composition includes a hydrophilically-modified polyorganosiloxane. The foam control composition is useful in a composition and method for reducing foam in a petroleum composition.INTRODUCTION

[0003] As crude oil rises from an oil wellbore, the crude oil typically moves up through risers towards the top of the wellbore. During this movement, the pressure of the crude oil decreases and any associated gas that may be trapped in the crude oil expands and is progressively released. On emerging from the wellbore, the crude oil is typically supplied to a triphase separator oil / gas / water to remove water and both free and associated gas, which would otherwise come out of solution when the crude oil is maintained at atmospheric pressure, e.g., during transport or storage. During this process of separating the gas from the crude oil, the crude oil typically forms a stable foam such that liquid crude oil is carried over into a stream of the gas, thereby creating production process problems. Such carryover situations can, if untreated, result in severe production losses and long equipment downtimes, such as those associated with pump cavitations. For these reasons, the stability and breaking of foams is a subject of great importance to the oil and gas industry.

[0004] Currently, various silicones are added to crude oil in a hydrophobic solvent to control foaming. However, since many of the silicones are hydrophobic themselves, they become incorporated in the crude oil. The presence of silicones and water in the crude oil may sometimes cause downstream damage to hydro treatment catalytic processes in refineries.

[0005] Furthermore, certain silicones, such as DOWSIL™ FS-1265, commercially available from The Dow Chemical Company of Midland, Michigan, USA, which are used to control foaming are fluorinated. There is a desire in various industries to replace fluorinated materials, such as fluorosilicones due to ECHA (Per- und polyflunrierte Alkylsubstanzen (PFAS) - ECHA) and other regulations. Accordingly, there are opportunities in the oil and gas industry to develop improvements for reducing the amount of foam in crude oil while minimizing or eliminating the use of fluorinated products.SUMMARY

[0006] A foam control composition comprises a hydrophilically-modified polyorganosiloxane. The foam control composition may be used in a composition and method for reducing foam in crude oil.BRIEF DESCRIPTION OF THE DRAWING

[0007] Figure 1 is a perspective view of an oil / gas separator that may be used in the method described herein.DETAILED DESCRIPTION

[0008] A reduced foam petroleum composition may be prepared by combining starting materials comprising: A) the crude oil; and B) the foam control composition. The foam control composition comprises Bl) the hydrophilically-modified polyorganosiloxane and optionally B2) a solvent.Starting Material A) Crude Oil

[0009] Starting material A) is crude oil. Crude oil is typically a mixture of hydrocarbons that exists in liquid phase underground and tends to remain a liquid at atmospheric pressure above ground. The crude oil may include 83% to 87% carbon, 10% to 14% percent hydrogen, 0.1% to 2% weight percent nitrogen, 0.05% to 1.5% oxygen, 0.05% to 6% sulfur, and less than 0.1% of metals. The crude oil may include 15% to 60% of alkanes (paraffins), 30% to 60% of naphthenes, 3% to 30% of aromatics, and a remainder of asphaltics.

[0010] The crude oil is not particularly limited and may be any known in the art. For example, the crude oil may have an API gravity, of 7° to 70°. As is known in the art, the API gravity is a measure of how heavy or light the crude oil is compared to water. If the API gravity is greater than 10, the crude oil is lighter than, and floats on, water. API gravity is an inverse measure of the relative density of the crude oil to the density of water. API gravity is gradated in degrees using a hydrometer.

[0011] More specifically, API gravity can be calculated as (141.5 / specific gravity of the crude oil) - 131.5. Typically, crude oil is classified as light, medium or heavy, according to its measured API gravity. Light crude oil typically has an API gravity higher than 31.10API (less than 870 kg / m3). Medium crude oil typically has an API gravity between 22.3°API and 31.1°API (870 kg / m3to 920 kg / m3). Heavy crude oil typically has an API gravity below 22.3° API (920 kg / m3to 1000 kg / m3). Extra heavy crude oil typically has an API gravity below 10.0°API (greater than 1000 kg / m3). Any one or more of these grades of crude oil may be utilized herein. In addition, the crude oil may be classified as natural or synthetic crude oil.

[0012] The crude oil may be present in the reduced foam petroleum composition in any amount but may be present in said composition in an amount of 1% to 99%, alternatively 5% to95%, alternatively 10% to 90%, alternatively 15% to 85%, alternatively 20% to 80%, alternatively 25% to 75%, alternatively 30% to 70%, alternatively 35% to 65%, alternatively 40% to 60%, alternatively 45% to 55%, and alternatively 40% to 50%, based on the weight of the reduced foam petroleum composition described herein. Alternatively, the amount of crude oil may be at least 1%, alternatively at least 10%, alternatively at least 25%, alternatively at least 50%, and alternatively at least 75%; while at the same time, the amount of crude oil may be up to 99%, alternatively up to 90%, alternatively up to 80%, and alternatively up to 75%, on the same basis.

[0013] The crude oil may include one or more impurities, for example, sulfur (e.g., hydrogen sulfide and sulfuric acid). Alternatively, the crude oil may include one or more glycols and / or fatty acids that may be used to (eventually) remove the sulfur content. The erode oil may be described as “wet”, i.e., including water. Wet crude oil contains water that is independent from the water that may be present in the foam control composition. For example, the wet crude oil may include 1% to 99%, alternatively 5% to 95%, 1 alternatively 0% to 90%, alternatively 15% to 85%, alternatively 20% to 80%, alternatively 25% to 75%, alternatively 30% to 70%, alternatively 35% to 65%, alternatively 40% to 60%, alternatively 45% to 55%, and alternatively 50% to 55%, of water based on weight of A) the crude oil.

[0014] The crude oil may also include one or more gases such as alkane gases, e.g., methane, propane, butane, and / or natural gas. The crude oil may include 1 to 50, alternatively 5 to 45, alternatively 10 to 40, alternatively 15 to 35, alternatively 20 to 30, and alternatively 25 to 30, volume percent of the one or more gases, e.g., H2S, CO and / or CO2. As is understood in the art, the amount of the one or more gases may fluctuate depending on various factors including an age of an oil well and type of crude oil. Alternatively, the crude oil may include less than 1%, alternatively < 0.9%, alternatively < 0.8%, alternatively < 0.7%, alternatively < 0.6%, alternatively < 0.5%, alternatively < 0.4%, alternatively < 0.3%, alternatively < 0.2%, alternatively < 0.1%, alternatively < 0.05%, and alternatively < 0.01%, of a gas based on a weight of the crude oil.Foam Control Composition

[0015] The reduced foam petroleum composition also includes the foam control composition. The foam control composition may be pre -formed in that the foam control composition is not formed upon contact with the crude oil. The foam control composition may exist independently from any contact with or near the crude oil. As described in greater detail below relative to a method, the foam control composition is typically formed and thereafter added to the crude oil. The foam control composition comprises Bl) the hydrophilically -modified polyorganosiloxane and optionally B2) the solvent, each introduced above.Starting Material Bl) Hydrophilically-Modified Polyorganosiloxane

[0016] Starting material Bl) is the hydrophilically-modified polyorganosiloxane. The hydrophilically -modified polyorganosiloxane comprises a hydrophilic moiety and a siloxane moiety. The hydrophilically -modified polyorganosiloxane comprises formula (I): R1-Si(R4)3, wherein R1is the hydrophilic moiety, which has fonnula (I):In formula (I), each D1is an independently selected divalent hydrocarbyl group of 2 to 6 carbon atoms. For example, D1may be an alkylene group, such as a linear alkylene group exemplified by ethylene, propylene, and hexylene. Alternatively, D1may be ethylene or propylene. In formula (I), subscript v is an integer with a value of 0 to 2, alternatively 0 to 1, and alternatively v = 0. In formula (I), each R is independently selectedfrom the group consisting of H and a group of formulaeach subscript u is independently an integer from 2 to 12, alternatively 2 to 10, alternatively 2 to 8, alternatively 2 to 6, and alternatively 2 to 4.

[0017] In formula (II), each R9is independently selected from the group consisting of H, OH,and a group of formulawherein each R10is independently selected from the group consisting of H and OH, and subscript z is an integer from 1 to 10; with the provisos that at least two per molecule of R9are OH, and no more than one of R9per molecule is the group of formula (III). Alternatively, in the group of formula (III) subscript z may be 1 to 8, alternatively 1 to 4, and alternatively 1 to 2. Alternatively, in the group of formula (I), each R9may be OH.

[0018] In formula (I), when subscript v > 0, then one R per molecule is the group of formula(II) and any other instances of R are H. Alternatively, in formula (1), R1may have formula, wherein D1, R9, and subscript u, are as described above, and subscript w is 1 to 3.

[0019] Alternatively, R1may have a formula selected from the group consisting of:each subscript x is independently an integer with a value of 2 to 6, and each subscript y is independently an integer with a value of 2 to 6.

[0020] Alternatively, R1may have a formula selected from the group consisting ofAlternatively, each R1mayGDL).

[0021] In the siloxane moiety (which has formula -Si(R4)3) in formula (I), each R4is independently selected from -OSi(R5)3 and R2, with the proviso that at least one of R4is -OSi(R5)3; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6)3, and -[OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3, and -[OSiR22]mOSiR23i wherein each R7is independently selected from R2, -DSi(R8)3, and -[OSiR22]mOSiR23; wherein each Rsis selected from R2and -[OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, alternatively 0<m<5, alternatively 0<m<4, alternatively 0<m<3, alternatively 0<m<2, alternatively 0<m<l wherein R4, R\ R6, R7, and R8are selected such that the polyorganosiloxane moiety may be, alternatively is, branched. The number of silicon atoms per molecule may be at least 3, and up to 10, silicon atoms per molecule.Alternatively, at least two of R4may be -OSi(R:’)3. Alternatively, each R4may be -OSi(R:’) . Alternatively, each R4may be -OSi(R2)3.

[0022] Each R2may be an independently selected alkyl group. Suitable alkyl groups for R2include alkyl groups such as methyl, ethyl, propyl (including isopropyl and n-propyl), and butyl (including n-butyl, t-butyl, isobutyl, and sec-butyl). Alternatively, R2may be an alkyl group of 1, 2 or 3 carbon atoms. Alternatively, each R2may be methyl.

[0023] Each D is independently selected from the group consisting of an oxygen atom and a divalent hydrocarbyl group. The divalent hydrocarbyl group for D may be an alkylene group of 2 to 10 carbon atoms. Examples include linear alkylene groups such as an ethylene group, a propylene group, a butylene group, and a hexylene group; and branched divalent hydrocarbyl groups such as a methyl methylene group, a methyl ethylene group, a 1 -methylphenyl group, and a 1 ,4-dimethyl butylene group. Alternatively, the divalent hydrocarbyl group for D may be ethylene or propylene. Alternatively, the divalent hydrocarbyl group for D may be ethylene. Alternatively, the divalent hydrocarbyl group for D may be propylene. Alternatively, each D may be an oxygen atom.

[0024] Starting material B 1), the branched polyorganosiloxane, may have 3 to 10 silicon atoms per molecule, alternatively 4 to 10 silicon atoms per molecule; alternatively 4 to 8 silicon atoms per molecule; and alternatively 4 to 7 silicon atoms per molecule. Alternatively, B 1) may have aformula selected from the group consisting of:and a combination of two or more of B 1-1), Bl-2), Bl-3), Bl-4), and B 1-5); wherein R2, R4, R5, and R6are as described above. Alternatively, in formula B 1-1), each R5may be R2, e.g., methyl. Alternatively, in formula Bl-2) each R4, each R\ and each R6may be R2, e.g., methyl.Alternatively, in formulas Bl-3) and Bl-4), each R' and each Rcmay be R2, e.g., methyl.Alternatively, in formula Bl -5, each R2may be methyl.

[0025] Alternatively, starting material Bl) may compriseN-(3-(l,l,l,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)-2,3,4,5,6-pentahydroxyhexanamide, which has formula:N-(3-(5-((l,l,l,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-l,l,l,3,7,9,9,9-octamethyl-3,7-bis((trimethylsilyl)oxy)pentasiloxan-5-yl)propyl)-2,3,4,5,6-pentahydroxyhexanamide, which has formula:GDL);N-(3-(l,l,l,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propyl)-2,3,4,5,6-pentahydroxyhexanamide, which has formula:N-(3-(l, 1,1, 5,5, 5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propyl)-2, 3,5,6-tetrahydroxy -4-(((2R,3R,5R,6R)-2, 3, 4, 6-tetrahydroxy-5-(hydroxymethyl)cyclohexyl)oxy)hexanamide, which has formulaLA);N-(3-(5-((l,l,l,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-l,l,l,3,7,9,9,9-octamethyl-3,7-bis((trimethylsilyl)oxy)pentasiloxan-5-yl)propyl)-2,3,5,6-tetrahydroxy-4-((3,4,5-trihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)hexanamide, which has formula:(SilO-LA);N-(3-(l,l,l,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propyl)-2,3,4,5,6- pentahydroxy-N-(2-(2,3,4,5,6-pentahydroxyhexanamido)ethyl)hexanamide, which has formula: ; or a combination of two or more thereof. Alternatively, starting material Bl) may comprise Si4-GDL. Alternatively, starting material Bl) may consist essentially of Si4-GDL.Alternatively, starting material Bl) may consist of Si4-GDL.

[0026] Alternatively, starting material Bl) can also be described by a ratio of silicon atoms per molecule to oxygen atoms in moiety R1(Z = #Si I #OR1). For example, Si4-GDL has a ratio Z= 4 / 6= 0.67; Si4-LA has a ratio Z= 4 / 11= 0.36; SilO-GDL has a ratio Z=10 / 6= 1.67; SilO-LA has a ratio Z= 10 / 11= 0.91. Starting material Bl) may have a ratio Z of 0.1 to 3, alternatively 0.3 to 1.7, alternatively 0.5 to 1.5, alternatively 0.6 to 1.2, alternatively 0.65 to 1, and alternatively 0.65 to 0.75, alternatively 0.1 to 0.75, alternatively 0.5 to 0.75, alternatively 0.6 to 0.75, alternatively 0.3 to 1, alternatively 0.5 to 1, alternatively 0.6 to 1, alternatively 0.5 to 1.7, alternatively 0.6 to 1.7.

[0027] Starting material Bl) may be synthesized by known methods, such as those disclosed in Adsorption and Aggregation Behavior of Tetrasiloxane-Tailed Surfactants Containing Oligo( ethylene oxide) Methyl Ether and a Sugar Moiety by Wang, Guoyong, et al., J. Phs.Chem. B 2011, 115, 3811-3818. Carbohydrate-Modified Siloxane Surfactants and Their Adsorption and Aggregation Behavior in Aqueous Solution by Wang, Guoyong, et al. J. Phs.Chem. B 2010, 114, 6872-6877, by varying appropriate starting materials. For example, an aminoalkyl-functional siloxane and / or an aminoalkyl-functional alkoxysilane with an additional organosiloxane may be reacted with a hydroxy -functional lactone compound such as lactobionic acid (with CAS #96-82-2), D-(+)-glucono-delta-lactone (with IUPAC name (3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-one and CAS #90-80-2), L-glucono-delta-lactone (with IUPAC name ((3S,4R,5R,6S)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-one) and CAS #52153-09-0), erythronolactone (also with name (-)-2,3-O-Isopropylidene-D-erythronolactone and CAS #25581-41-3), galactonolactone (also with name L-Galactono-l,4-lactone and CAS #1668-08-2), and mannonolactone. All of these hydroxy-functional lactone compounds are commercially available from Sigma Aldrich, Inc. of St. Louis, Missouri, USA. Suitable aminoalkyl-functional siloxanes are also known in the art and commercially available. For example, 3-aminopropyltris(trimethylsiloxy) silane (with CAS # 25357-81-7) is available from Gelest, Inc. of Morrisville, Pennsylvania, USA. Alternatively, the aminoalkyl-functional siloxane may be prepared as described, for example in US Patent Application Publication 2022-0106337 to Liu, et al. Other amino-alkyl functional siloxanes that may be used as starting materials to prepare B 1 ) include 3 -( 1 , 1 , 1 ,5,5,5-hexamethyl-3 -((trimethy lsilyl)oxy )trisiloxan-3-yl)propan- 1 -amine; N1-(3-(l,l,l,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propyl)ethane-l,2-diamine: 3-(5-((l , 1 , 1 ,3 ,5,5,5-heptamethyltrisiloxan-3-yl)oxy)- 1 ,1,1 ,3,7,9,9,9-octamethyl-3 ,7-bis((trimethylsilyl)oxy)pentasiloxan-5-yl)propan- 1 -amine; or N1-(3-(5-((l , 1 , 1, 3, 5,5,5-heptamethyltrisiloxan-3-yl)oxy)-l,LL3,7,9,9,9-octamethyl-3,7-bis((trimethylsilyl)oxy)pentasiloxan-5-yl)propyl)ethane-l,2-diamine.

[0028] Starting material B2) is an optional solvent in which starting material B 1) can be dissolved or dispersed. Starting material B2) may comprise an organic solvent, such as a hydrocarbon solvent; water; or a combination of organic solvent and water. Suitable organic solvents include aliphatic hydrocarbons, aromatic hydrocarbons, ketones, alcohols, esters, glycol ethers, and monoterpenes. Examples of aliphatic hydrocarbons include hexane, heptane, and octane. Examples of aromatic hydrocarbons include benzene, toluene, and xylene. Examples of ketones include acetone and methyl isobutyl ketone (MIBK). Examples of suitable alcohols include monohydric alcohols such as isopropanol and n-pentanol. Examples of suitable esters include n-propyl acetate and isobutyl acetate. Examples of monoterpenes include limonene. Other organic solvents include petroleum distillates such as light naphtha. The organic solvents are known in the art and are commercially available, e.g., from Fischer Scientific or ExxonMobil.

[0029] Alternatively, starting material B2) the solvent may comprise water. The water is notgenerally limited, and may be utilized neat (z.e., absent any carrier vehicles and / or solvents), and / or pure (z'.e., free from, or substantially free from, minerals and / or other impurities). For example, the water may be processed or unprocessed prior to combination with starting material Bl). Examples of processes that may be used for purifying the water include distilling, filtering, deionizing, reverse osmosis, and combinations of two or more thereof. Alternatively, the water may be unprocessed (e.g., the water may be tap water, i.e., provided by a municipal water system or well water, used without further purification). Alternatively, the water may further comprise dissolved species. For example, the water may comprise sea water, which comprises dissolved ions. Alternatively, the water may be purified before combination with starting material Bl). Alternatively, the water may be utilized as a mixture (e.g., solution or suspension) comprising an organic solvent, such as any of those listed above. The amount of water depends on various factors including the solubility of starting material Bl) and whether the organic solvent is present, however, when both the organic solvent and water are present the amount of water may be at least 10%, alternatively at least 20%, alternatively at least 30%, alternatively at least 40%, and alternatively at least 50%, based on combined weights of the organic solvent and the water; while at the same time the amount of water may be up to 80%, alternatively up to 70%, alternatively up to 60%, and alternatively up to 50%, on the same basis.

[0030] Starting material B2), the solvent, may be utilized in any amount, which will be selected by one of skill in the art, depending on various factors, e.g., the species selected for starting material Bl), desired dosage and pumping ability, and whether water or an organic solvent (or both) will be used. The organic solvent and the water are optional, so their amounts may be zero weight percent. However, when starting material B2) the solvent is used, the amounts of starting materials Bl) and B2) in the foam control composition may be sufficient to provide 1 weight % to 30 weight %, alternatively 5 weight % to 15 weight %, of starting material Bl) and 70 weight % to 99 weight %, alternatively 85 weight % to 95 weight %, of starting material B2). Alternatively, starting material Bl) may be used in an amount of at least 5%, alternatively at least 6%, alternatively at least 7%, alternatively at least 8%, alternatively at least 9%, and alternatively at least 10%, based on combined weights of all starting materials used to make the foam control composition, while at the same time, the amount of starting material B2) may be up to 50%, alternatively up to 15%, alternatively up to 14%, alternatively up to 13%, alternatively up to 12%, alternatively up to 11%, and alternatively up to 10%, on the same basis.

[0031] The foam control composition is used in the reduced foam petroleum composition in an amount sufficient to provide 1 part by weight to 100 parts by weight of starting material Bl), per one million parts by weight of A) the crude oil. Alternatively, the amount may be at least 1ppm, alternatively at least 10 ppm, alternatively at least 20 ppm, alternatively at least 25 ppm, alternatively at least 30 ppm, alternatively at least 40 ppm, and alternatively at least 50 ppm; while at the same time the amount may be up to 100 ppm, alternatively up to 90 ppm, alternatively up to 75 ppm, alternatively up to 60 ppm, and alternatively up to 50 ppm, on the same basis described above.Method of Use

[0032] The foam control composition is typically used to reduce foam height of a petroleum composition comprising crude oil. However, the use of the foam control composition is not particularly limited. For example, the foam control composition may be used in any location or in any method that is utilized to drill for, or process, petroleum. For example, the foam control composition may be utilized on or in an oil rig, such as an off-shore oil platform. Sea water may be used in this off-shore application to form or dilute the foam control composition.Alternatively, the foam control composition may be utilized at or in a petroleum refinery. The foam control composition may be useful for decreasing the number of containers in off-shore oil platforms providing safer solutions for the water / gas / oil separation in crude oil primary processing.

[0033] The foam control composition and / or methods of the present invention may be free of silica. Thus, foam control composition and / or the reduced foam petroleum composition may have zero weight percent added silica. The crude oil after treatment with the foam control composition and / or method of the present invention may have reduced residual silicon content, which may be beneficial for subsequent processing and refining steps. The foam control composition and methods of the present invention are useful for the processing of crude oil, for example, added just before the three-phase separator in the first step of oil processing.Accordingly, the foam control composition may be used after crude oil extraction or production from subterranean formations.Method Of Reducing Foam In Crude Oil Disposed In A Tank:

[0034] The disclosure also provides a method of reducing foam (32) in crude oil (30) disposed in a tank (10). The tank (10) may be further defined as an oil / gas separator, e.g., as set forth in Figure 1, or any type of container. Alternatively, the tank (10) may be further defined as any vessel that separates fluids from an oil well into gas and two types of liquids: crude oil (30) and water (28). The tank (10), e.g., a (three-phase) separator, can be horizontal, vertical or spherical. The separator may be further defined as a free -water (28) knockout (FWKO) separator. The tank (10) may be further described as a package. The package or tank (10) may be fitted to a well head and disposed after a choke valve but before a production manifold. The package or tank (10) may allow the crude oil (30) to be pumped onto or into a pipeline, storage tank, tanker,or other container (not shown).

[0035] The method includes the step of supplying the crude oil (30) to the tank (10). The crude oil (30) may be supplied to the tank (10) by any convenient means, such as by pumping the crude oil (30) from an oil well into the tank (10), e.g., through one or more valves, pumps, lines, or pipes. For example, the crude oil (30) may leave the well head (not shown) under high pressure of greater than 23,000 psi (1,600 atm) which may be dampened at the choke valve or blow-out preventer (not shown). The crude oil (30) may then flow into the tank (10). For example, the crude oil (30) may be supplied to the tank (10) through a line (12), as set forth in Figure 1.

[0036] The method also includes the step of supplying the foam control composition to the tank (10). The foam control composition may be supplied by any method in the art. For example, the foam control composition may be formed off site and used directly, formed off site and then diluted and used on site, or formed on-site and either used or further diluted. The foam control composition may be formed prior to being supplied to the tank (10) or may be formed from multiple streams coming together in or immediately before the tank (10). The foam control composition may be formed before any contact with the crude oil (30). In an example, the foam control composition may be supplied to the tank (10) via line (16), as set forth in Figure 1.

[0037] The step of supplying the crude oil (30) to the tank (10) and the step of supplying the foam control composition to the tank (10) may occur sequentially, in any order, or simultaneously. These steps typically result in a combination or mixture being formed in the tank (10) subsequent to these steps. More specifically, the combination typically includes the crude oil (30), the hydrophilically-modified polyorganosiloxane, and water. Most typically, the water of the combination includes the water from the crude oil (30) and may optionally include water from the foam control composition, when water is used in the foam control composition.

[0038] The method also includes the step of separating the crude oil (30) from the water (28) in the presence of the hydrophilically-modified polyorganosiloxane. For example, the crude oil (30) may be separated in the gas / oil separator, e.g., as set forth in Figure 1, and may flow over a vertical wall (18). The crude oil (30) may be removed from the tank (10) via a line (20), such as in Figure 1. The water (28) may also be removed from the tank (10) by any method, e.g., through a line (26). Moreover, the method may include the step of removing any miscellaneous sediment (22), such as rocks and / or dirt using a removal line (24), as set forth in Figure 1. The method may also include the step of removing the one or more aforementioned gases, e.g., through line (14), as set forth in Figure 1. Separating produces a supply of crude oil (30) (e.g. flowing out of line (20)).

[0039] The combination of the crude oil (30), water (28), and the hydrophilically-modifiedpolyorganosiloxane may exhibit a foam (32) having a height that is at least 50 vol%, alternatively at least 55 vol%, alternatively at least 60 vol%, alternatively at least 65 vol%, alternatively at least 70 vol%, alternatively at least 75 vol%, alternatively at least 80 vol%, alternatively at least 85 vol%, alternatively at least 90 vol%, or alternatively at least 95 vol%, percent by volume less than a height of a foam produced by a control combination of the crude oil (30) and the water (28) in the absence of the foam control composition. The difference in foam height may be calculated as a direct comparison to a control composition that is identical except for the instant foam control composition. Alternatively, the difference in foam height may be calculated as described in the Examples below.EXAMPLES

[0040] The following Examples are provided to illustrate the invention to one skilled in the art and are not to be construed so as to limit the invention set forth in the claims. Starting materials used in these examples are summarized in Table 1.Table 1 - Starting Materials

[0041] Si4-GDL was synthesized as described in Carbohydrate-Modified Siloxane Surfactants and Their Adsorption and Aggregation Behavior in Aqueous Solution by Wang, Guoyong, et al. J. Phs. Chem. B 2010, 114, 6872-6877.

[0042] In this Reference Example 1, samples of foam control compositions were prepared by dissolving a foam control additive in a solvent. Additives, solvents, and amounts are summarized below in Table 2.Table 2 - Foam Control Compositions

[0043] The foam control compositions in Table 2 were used to evaluate foam control performance trials in Oil-Gas separation according to the Method to Evaluate Foaming in Petroleum described in the Brazilian Journal of Petroleum and Gas, v.5, n.1 , p. 025-033, 2001. The methodology is based on a quick depressurization test with aging cells and roller oven, simulating the real foaming conditions at the production units. A total of 150 mL of each oil sample was transferred to a compression cell (High Temperature Aging Cell, Fann). This cell was then sealed and connected to a compressed air line with a rubber hose. The cell was pressurized to 200 psi with Nitrogen, measured with a manometer, and held at each pressure for three minutes by shutting the ball valve. The compression cell was placed in a Fann 704Es roller oven, at room temperature (21 °C). The cell was then allowed to rotate at 50 rpm for two hours. After that, the compression cell was connected to a 100-mL graduated cylinder through a spiralshaped rod containing 50 coils. The cell was placed vertically upside-down, with cell’s outlet pointing downward. Then the cell’s valve was opened to depressurize and collect the oil in the graduated cylinder through the coil tube. When the oil volume in the cylinder reached 80 mL, the valve was closed and the time count started. The foam height was read at intervals of time until constant consecutive values were attained, indicating there was no remaining foam in the graduated cylinder.

[0044] Two different crude oils were tested, with API 26° (offshore pre-salt formation from Brazil, free of oilfield chemicals and with water level below 1%) and API 21° (onshore formation from Argentina, previously dehydrated with an organic demulsifier and diluted withTable 3 - Crude Oils

[0045] The crude oils were tested without any foam control additive (Control) and with foam control compositions in amounts sufficient to provide 50 ppm of the foam control additive as described in Table 2.

[0046] Based on the instant foam volumes, %Foam was calculated according to the Equation 1 for specific times t - in average, every 30 seconds. The tests were conducted in triplicate for each sample, the curves were plotted with a 95% confidence interval. The area under the curve (ACC) of the graph %Foam by time was calculated using the trapezoid rule, a numerical integration representing the foam lifetime.% Foam = 100 x (Vt - Vf) / Vf (Equation 1 )In Equation 1 : Vt = total volume (liquid crude + foam) at time t; and Vf = final volume (liquid crude), after complete foam rupture.

[0047] Table 4 summarizes the results obtained with the Crude Oil sample from Brazil.Table 4 - Foam Control Results (BR)

[0048] In the crude oil sample from Brazil API 26°, from offshore pre-salt formation, Reference- 1 showed an intermediate average value of initial foam (antifoam effect), but the worst foam lifetime among the foam control additives tested (defoamer performance). This aligned well with feedback from the production units applying this type of foam control additive: bis-OH terminated polydimethylsiloxane reduces the foam as the fluids reach the separation vessels, but bis-OH terminated polydimethylsiloxane has a low persistency, requiring reapplications or high use levels in challenging operation conditions.

[0049] Si4-GDL outperformed Reference-2, a fluorosilicone that is considered the gold standard for foam control in challenging oil-gas separations. The samples with Si4-GDL and Reference-2 each took a similar time to completely break all the foam, but surprisingly Si4-GDL showed a higher preventive effect, with a lower initial foam volume, resulting also in a shorterfoam lifetime.

[0050] Table 5 summarizes the results obtained with the Crude Oil sample from Argentina. Table 5 - Foam Control Results (AR)

[0051] In the crude oil from Argentina API 21 °, from onshore formation, previously dehydrated and diluted in 15% of hexane, Reference-3 provided profoaming action, which was worse than the Control. Reference-3 was the only additive showing a profoaming performance, resulting in a slightly lower initial foam volume than the control, but a longer foam lifetime. In contrast, Si4-GDL and Reference-2 had comparable initial foam volume and total breaking time. The foam profile for Si4-GDL showed a slightly slower defoaming effect, resulting in a longer foam lifetime when compared to Reference-2 (the fluorosilicone), however, defoaming effect with Si4-GDL was much better (faster) than both the Control and Reference-3.Industrial Applicability

[0052] Si4-GDL demonstrated better foam control performance than Reference- 1 (bis-OH-terminated polydimethylsiloxane) in crude oil API 26°, reducing the initial foam by more than 5%; and the foam lifetime by 60%. Si4-GDL also showed a better performance than Reference-2 (fluorosilicone) in crude API 26°, reducing both the initial foam volume (16% reduction) and foam lifetime (26% reduction). In cmde oil API 21°, Si4-GDL outperformed Reference-2 regarding initial foam volume (7% reduction). In this Argentinean crude, a heavier oil diluted with hexane, Si4-GDL showed a significant reduction in the initial foam volume and foam lifetime when compared to the Control: 35% and 48%, respectively. The examples above demonstrate that Si4-GDL is an alternative to fluorine-containing fluorosilicones with surprisingly good foam control performance for crude oil.

[0053] The foam control composition described herein is an alternative to conventional fluorine-containing foam control additives, wherein the foam control composition herein may provide a benefit of improved antifoam performance, improved defoaming performance, or both, when used in a petroleum composition with cmde oil.Definitions and Usage of Terms

[0054] All amounts, ratios, and percentages are by weight unless otherwise indicated. The amounts of all starting materials in a composition total 100% by weight. The SUMMARY and ABSTRACT are hereby incorporated by reference. The articles ‘a’, ‘an’, and ‘the’ each refer to one or more, unless otherwise indicated by the context of specification. The singular includes the plural unless otherwise indicated. The disclosure of ranges includes the range itself and also anything subsumed therein, as well as endpoints. The term "antifoam" and its derivatives (e.g., antifoamer and antifoaming) refer to a preventative agent added before foaming occurs, while "defoam" and its derivatives (e.g., defoamer and defoaming) describe a substance added to preexisting foam to eliminate it. Both parameters are relevant to optimize the offshore operations (performance of the foam control composition in oil and gas applications).

[0055] The abbreviations used herein have the definitions in Table 6.Table 6 - Abbreviations<><>Embodiments of the Invention

[0056] In a first embodiment, an agent for reducing foam in a petroleum composition wherein said agent comprises a hydrophilically-modified branched polyorganosiloxane compound represented by formula R^SilR4)?, wherein R1is a hydrophilic group of formula; wherein subscript w is an integer with a value of 1 to 3; eachD1is an independently selected divalent hydrocarbyl group of 2 to 6 carbon atoms: subscript u is an integer with a value of 2 to 12; each R9is independently selected from the group consisting ofH, OH, and a group of formulawherein each R10is independently selected from the group consisting of H and OH, and subscript z is an integer from 1 to 10: with the provisos that at least two per molecule of R9are OH, and no more than one of R9per molecule is the group of formula (III); each R4is independently selected from -OSi(R5)3 and R2, with the proviso that at least two of R4are -OSi(R5)3; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6)3, and -[OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3, and -[OSiR22]mOSiR23; wherein each R7is independently selected from R2, -DSi(R8)3, and -[OSiR22]mOSiR23; wherein each Rsis selected from R2and -[OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, and wherein R4, R , R6, R7, and R8are selected such that the polyorganosiloxane moiety is branched and has 4 to 10 silicon atoms per molecule.

[0057] Tn a second embodiment, an agent for reducing foam in a petroleum composition wherein said agent comprises a hydrophilically-modified branched polyorganosiloxane compound represented by formula RCSi(R4)3, wherein R1is a hydrophilic group of formula;each R4is independently selected from -OSi(R5)3 and R2, with the proviso that at least two of R4are -OSi(R5)3; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6) , and -[OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3, and -[OSiR22]mOSiR23; wherein each R7is independently selected from R2, -DSi(R8)3, and -[OSiR22]mOSiR23; wherein each R8is selected from R2and -[OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, and wherein R4, R5, R6, R7, and R8are selected such that the polyorganosiloxane moiety is branched and has4 to 10 silicon atoms per molecule.

[0058] In a third embodiment, a foam control composition (for reducing foam in a petroleum composition) wherein said foam control composition comprises a branched polyorganosiloxane compound represented by formula R1-Si(R4)3, wherein R1is a hydrophilic group of formula<; each R4is independently selected from -OSi(R5)s and R2, with the proviso that at least two of R4are -OSi(R5)a; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6)3, and -[OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3, and -[OSiR22]mOSiR23; wherein each R7is independently selected from R2, -DSi(R8)3, and -[OSiR22]mOSiR23; wherein each R8is selected from R2and -[OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, and wherein R4, R5, R6, R7, and R8are selected such that the polyorganosiloxane moiety is branched and has 4 to 10 silicon atoms per molecule; and a solvent.

[0059] In a fourth embodiment, in the foam control composition of the third embodiment, the solvent comprises an organic solvent and sea water.

[0060] In a fifth embodiment, in any one of the first to fourth embodiments, wherein each D is an oxygen atom and each R2is a methyl group.

[0061] In a sixth embodiment, in any one of the first to fifth embodiments, wherein the petroleum composition comprises crude oil and an organic solvent.

[0062] In a seventh embodiment, in any one of the first to sixth embodiments, the hydrophilically-modified branched polyorganosiloxane has formula:, wherein each R3is methyl.

[0063] In an eighth embodiment, in any one of the first to seventh embodiments, the branched polyorganosiloxane comprises N-(3-(l,l,l,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propyl)-2,3,4,5,6-pentahydroxyhexanamide.

[0064] In a ninth embodiment, in any one of the first to eighth embodiments, the petroleumcomposition comprises 1 ppm to 100 ppm of the hydrophilically-modified branched polyorganosiloxane, 0 to 25 weight % of a solvent, and a balance to 100 weight % of crude oil.

Claims

CLAIMS:

1. A reduced foam petroleum composition comprising:A) crude oil; andB) a foam control composition comprising:Bl) a hydrophilically-modified polyorganosiloxane comprising a hydrophilic moiety and a polyorganosiloxane moiety, wherein the hydrophilically-modified polyorganosiloxane has formula R1-Si(R4)s, wherein R1is the hydrophilic moiety, which has formula (I)whereinsubscript v is an integer with a value of 0 to 2;each D1is an independently selected divalent hydrocarbyl group of 2 to 6 carbon atoms;each R is independently selected from the group consisting of H and a group of formula (11)each subscript u is independently an integer with a value from 2 to 12; each R9is independently selected from H, OH, and a group of formula (III)whereineach R10is independently selected from the group consisting of H and OH, andsubscript z is an integer from 1 to 11 ;with the provisos that at least two per molecule of R9are OH, andno more than one of R9per molecule is the group of formula (Ill); and with the provisos that one R per molecule is the group of formula (II), and when subscript v > 0, then all R are H except the one;each R4is independently selected from -OSi(R5)s and R2, with the proviso that at least one of R4is -OSi(R5)3; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6)3, and - [OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3, and -[OSiR22]mOSiR23; wherein each R7is independently selected from R2, - DSi(R8)3, and -[OSiR22]mOSiR23; wherein each R8is selected from R2and - [OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, and wherein R4, R5, R6, R7, and R8are selected such that the polyorganosiloxane moiety has 3 to 10 silicon atoms per molecule; andoptionally B2) a solvent.

2. The reduced foam petroleum composition of claim 1, wherein B2) the solvent is present, and the solvent is selected from the group consisting of an organic solvent, water, and a combination of both an organic solvent and water.

3. The reduced foam petroleum composition of claim 2, wherein the reduced foam petroleum composition is prepared by a method comprising combining A) the crude oil, and B) a foam control composition comprising 1 weight % to 30 weight% of Bl) the hydrophilically-modified polyorganosiloxane and 70 weight % to 99 weight % of B2) the solvent.

4. The reduced foam petroleum composition of any one of claims 1 to 3, wherein B 1) the hydrophilically-modified polyorganosiloxane has formula;, wherein each R is methyl.

5. The reduced foam petroleum composition of any one of claims 1 to 4, wherein Bl) the hydrophilically-modified polyorganosiloxane comprises6. The reduced foam petroleum composition of any one of claims 1 to 5, wherein B 1) the hydrophilically-modified polyorganosiloxane is present in the reduced foam petroleum composition in an amount of 1 to 100 parts by weight per one million parts by weight of A) the crude oil.

7. The reduced foam petroleum composition of any one of claims 1 to 6 wherein A) the crude oil is further defined as heavy crude oil having an API gravity less than 22.3°.

8. The reduced foam petroleum composition of any one of claims 1 to 6, wherein A) the crude oil is further defined as medium crude oil having an API gravity from 22.3° to 31.1°.

9. Use of the composition of any one of claims 1-8 in a petroleum rig.

10. A method of reducing foam in crude oil disposed in a tank, said method comprising the steps of:(I) supplying the crude oil to the tank wherein the crude oil comprises water;(II) supplying a foam control composition to the tank wherein the foam control composition comprises:a hydrophilically -modified polyorganosiloxane comprising a hydrophilic moiety and a polyorganosiloxane moiety, wherein the hydrophilically-modified polyorganosiloxane has formula R'-Si(R4)3, wherein R1is the hydrophilic moiety and has formula (I) the hydrophilically-modified polyorganosiloxane has formula R1-Si ( Rl) , wherein R1is thehydrophilic moiety, which has formula (wherein subscript v is an integer with a value of 0 to 2;each D1is an independently selected divalent hydrocarbyl group of 2 to 6 carbon atoms;each R is independently selected from the group consisting of H and a group of formula (II), whereineach subscript u is independently an integer with a value from 2 to 12;each R9is independently selected from H, OH, and a group of formula (III)whereineach R10is independently selected from the group consisting of H and OH, andsubscript z is an integer from 1 to 11 ;with the provisos that at least two per molecule of R9are OH, and no more than one of R9per molecule is the group of formula (III); and with the provisos that one R per molecule is the group of formula (II), and when subscript v > 0, then all R are H except the one;each R4is independently selected from -OSi(R5)s and R2, with the proviso that at least one of R4is -OSi(R5)3; wherein each R2is a monovalent hydrocarbon group; wherein each R5is independently selected from R2, -DSi(R6)3, and - [OSiR22]mOSiR23; wherein each R6is independently selected from R2, -DSi(R7)3,and -|OSiR22|mOSiR23; wherein each R7is independently selected from R2, - DSi(R8)3, and -[OSiR22]mOSiR23; wherein each R8is selected from R2and - [OSiR22]mOSiR23; wherein each D is selected from oxygen and a divalent hydrocarbyl group, wherein 0<m<9, and wherein R4, R5, R6, R7, and R8are selected such that the polyorganosiloxane moiety has 3 to 10 silicon atoms per molecule; andoptionally B2) a solvent;wherein subsequent to steps (I) and (II) a combination comprising the crude oil, water, and the branched polyorganosiloxane is formed: and(III) separating the crude oil from the water in the presence of the branched polyorganosiloxane, wherein the step of (III) separating is accomplished in the presence of the branched polyorganosiloxane.

11. The method of claim 10, wherein the tank is further defined as a gas / oil separator and the crude oil further comprises an alkane gas.

12. The method of any claim 10 or claim 11, further comprising the step of removing water from the tank.

13. The method of any one of claims 10 to 12, wherein the step of (III) separating produces a supply of crude oil that includes less than 50 percent by weight of the Bl) the branched polyorganosiloxane based on a total amount of Bl) the hydrophilically-modified polyorganosiloxane supplied to the tank.

14. The method of any one of claims 10 to 13, wherein the combination comprising the crude oil, the solvent, and the hydrophilically-modified polyorganosiloxane exhibits a foam having a height that is at least 50 percent less than a height of a foam produced by a control combination of the crude oil and the solvent in the absence of the hydrophilically-modified polyorganosiloxane.

15. Use of the method of any one of claims 10 to 14 in a petroleum rig.

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