Hydrocarbon formation treatment micellar solutions

Abstract

A hydrocarbon formation treatment micellar solution fluid and its use in treating underperforming hydrocarbon formations is described and claimed. A hydrocarbon formation treatment micellar solution fluid wherein the micellar solution fluid comprises water, a non-terpene oil-based moiety, a brine resistant aqueous colloidal silica sol; and optionally a terpene or a terpenoid, wherein the brine resistant aqueous colloidal silica sol has silica particles with a surface that is functionalized with at least one moiety selected from the group consisting of a hydrophilic organosilane, a mixture of hydrophilic and hydrophobic organosilanes, or a polysiloxane oligomer, wherein the brine resistant aqueous colloidal silica sol passes at least two of three of these brine resistant tests: API Brine Visual, 24 Hour Seawater Visual and API Turbidity Meter, and wherein, when a terpene or terpenoid is present, the ratio of total water to terpene or terpenoid is at least about 15 to 1.

Claims

1. A hydrocarbon formation treatment micellar solution fluid wherein the micellar solution fluid comprises a) water b) a non-terpene oil-based moiety, and c) a brine resistant aqueous colloidal silica sol; wherein the brine resistant aqueous colloidal silica sol has silica particles surface functionalized with at least one moiety selected from the group consisting of (i) a hydrophilic organosilane, (ii) a mixture of hydrophilic and hydrophobic organosilanes, and (iii) a polysiloxane oligomer, wherein the silica particles have an average diameter of between about 1 nm and about 100 nm, and wherein the brine resistant aqueous colloidal silica sol passes these brine resistant tests: API Brine Visual and 24 Hour Seawater Visual.

2. The hydrocarbon formation treatment micellar solution fluid of claim 1, further comprising a terpene or terpenoid, wherein the ratio of total water to terpene or terpenoid is at least about 15 to 1.

3. The hydrocarbon formation treatment micellar solution fluid of claim 2, wherein the ratio of total water to the terpene or terpenoid is at least about 30 to 1.

4. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the silica particles have an average diameter of between about 5 nm and about 30 nm.

5. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the silica particles have an average diameter of less than or equal to 25 nm.

6. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the brine resistant aqueous colloidal silica sol has silica particles surface functionalized with the hydrophilic organosilane.

7. The hydrocarbon formation treatment micellar solution fluid of claim 6, wherein the hydrophilic organosilane includes a glycidyl group.

8. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the brine resistant aqueous colloidal silica sol has silica particles surface functionalized with the mixture of hydrophilic and hydrophobic organosilane.

9. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the brine resistant aqueous colloidal silica sol has silica particles surface functionalized with the polysiloxane oligomer.

10. The hydrocarbon formation treatment micellar solution fluid of claim 9, wherein the polysiloxane oligomer comprises Ingredient A and Ingredient B, wherein: (1) Ingredient A is glycidoxypropyltrimethoxysilane and (2) Ingredient B is selected from the group consisting of methacryloxypropyltrimethoxysilane, isobutyltrimethoxysilane, vinyltrimethoxysilane, 2-(7-oxabicyclo[4.1.0]hept-3-yl)ethyltrimethoxysilane, and hexamethyldisiloxane.

11. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the hydrophilic organosilane monomer unit exhibits a critical surface tension in the range of from about 40 mN/m to about 50 mN/m.

12. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the hydrophobic organosilane monomer unit exhibits a critical surface tension in the range of from about 15 mN/m to about 39.5 mN/m.

13. The hydrocarbon formation treatment micellar solution fluid of claim 1, wherein the hydrophilic organosilane monomer unit exhibits a critical surface tension in the range of from about 40 mN/m to about 50 mN/m and wherein the hydrophobic organosilane monomer unit exhibits a critical surface tension in the range of from about 15 mN/m to about 39.5 mN/m.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) The following definitions are provided to aid those skilled in the art in understanding the detailed description of the present invention.

(2) The term “surfactant” refers to a soluble, or partially soluble compound that reduces the surface tension of liquids, or reduces interfacial tension between two liquids, or a liquid and a solid by congregating and orienting itself at these interfaces.

(3) The term “amphoteric” refers to surfactants that have both positive and negative charges. The net charge of the surfactant can be positive, negative, or neutral, depending on the pH of the solution.

(4) The term “anionic” refers to those surfactants that possess a net negative charge.

(5) The term “cationic” refers to those surfactants that possess a net positive charge.

(6) As used herein, the term “treatment,” or “treating,” refers to any operation that uses a fluid in conjunction with a desired function and/or for a desired purpose. The term “treatment,” or “treating,” does not imply any particular action by the fluid or any particular component thereof.

(7) In an embodiment, one component is a “terpene” based liquid that makes up the oil phase. A terpene is derived biosynthetically from units of isoprene, which has the molecular formula C.sub.5H.sub.8. The basic molecular formulae of terpenes are multiples of that, (C.sub.5H.sub.8).sub.n where n is the number of linked isoprene units. This is called the isoprene rule or the C.sub.5 rule. The isoprene units may be linked together “head to tail” to form linear chains or they may be arranged to form rings. One can consider the isoprene unit as one of nature's common building blocks. Commercially available terpenes are available online from different websites including buy-terpenes.com and www.vertecbiosolvents.com/vertecbio-dlr.

(8) Limonene is a colorless liquid hydrocarbon classified as a cyclic terpene. The more common d-isomer possesses a strong smell of oranges..sup.[1] It is used in chemical synthesis as a precursor to carvone and as a renewables-based solvent in cleaning products. The less common 1-isomer is found in mint oils and has a piney, turpentine-like odor. For purposes of this invention it has been found that a better performing oil-well treatment fluid will be created if the amount of Limonene present in the treatment fluid is less than 0.01 wt. %.

(9) Other terpenes or formulated terpene mixtures are commercially available, including VertecBio™DLR. VertecBio™DLR is a high-powered, environmentally friendly alternative for d-limonene. It has a pleasant fruity odor and is ideal for parts cleaning and degreasing. It cuts through oily materials, adhesives and inks. VertecBio™DLR is available from Vertec Biosolvents, www.vertecbiosolvents.com/vertecbio-dlr

(10) In contrast to existing patents, U.S. Pat. Nos. 8,101,812; 8,272,442, 8,404,107, 8,522,876, 8,685,234 and 9,181,468 that teach the :flooding” of an underperforming hydrocarbon containing formation with a non-aqueous terpene, which is typically turpentine, the presence of terpene or terpenoid in the micellar solution fluid is optional, and when terpene- or terpenoid is present, it is present is a very low amount such that the ratio of total water in the fluid to total terpene or terpenoid is at least about 15 to 1 an preferably is at least about 30 to 1.

(11) In another embodiment, non-terpenes are available for the oil phase of the treatment fluid. Non-terpene, oil phase materials include VertecBio™ Gold, which is a methyl soyate material available from Vertec Biosolvents. www.vertecbiosolvents.com/vertecbio-dlr

(12) In an embodiment VertecBio™DLR is used in the formulation.

(13) In an embodiment VertecBio™Gold is used in the formulation.

(14) In an embodiment terpene-based and non-terpene-based oil phases are used in combination.

(15) Regarding the surfactant chosen to be used: a range of surfactants can be used including anionic, nonionic, cationic, or amphoteric surfactants including mixtures of these. Surfactants may be selected from the group of commercially available surfactants consisting of ethoxylated nonyl phenol, sodium stearate, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, alkyl olefin sulfonates, laurylamine hydrochloride, trimethyldodecylammonium chloride, cetyl trimethylammonium chloride, polyethylene oxide alcohol, ethoxylated castor oil, propoxylated castor oil, ethoxylated-propoxylated castor oil, ethoxylated soybean oil, propoxylated soybean oil, ethoxylated-propoxylated soybean oil, ethylene oxide-propylene oxide copolymers, sodium trideceth sulfate, ethoxylated tetramethyl decyne alcohol, alkylphenolethoxylate, Polysorbate 80, ethoxylated or propoxylated polydimethylsiloxane, dodecyl betaine, lauramidopropyl betaine, cocamidopropyl betaine, cocamidopyropyl-2-hydroxypropyl sulfobetaine, alkyl aryl sulfonates, protein-surfactant complexes, fluorosurfactants, polyethyleneoxide alkyl ether phosphates.

(16) Ethylan™ 1206 is a nonionic surfactant—Ethylene Oxide/Propylene Oxide copolymer available commercially, from among other suppliers, AkzoNobel. In an embodiment, the surfactant is a nonionic surfactant, which is a copolymer of ethylene oxide and propylene oxide. www.akzonobel.com

(17) A mixture of surfactants can also be used, rather than just one surfactant. Typically, the mixture mostly comprises a large amount of anionic surfactant and a relatively small amount of non-ionic surfactant.

(18) In an embodiment, alkyl olefin sulfonate is the surfactant used in the formulation.

(19) One suitable alkyl olefin surfactant is Calsoft® AOS-40, a 40% solution of sodium C.sub.14-16 alpha olefin sulfonate available from Pilot Chemical. www.ulprospector.com/en/na/Cleaners/Detail/920/37364/Calsoft-AOS-40

(20) A mixture of surfactants can also be used, rather than just one surfactant. Typically, the mixture mostly comprises a large amount of anionic surfactant and a relatively small amount of non-ionic surfactant.

(21) In an embodiment, also present in the fluid is a C.sub.1-C.sub.6 alcohol, an alcohol co solvent and water.

(22) In an embodiment, the alcohol is isopropanol.

(23) In an embodiment, the alcohol cosolvent is ethylene glycol.

(24) A surface treated aqueous colloidal silica is typically added to the formulation. The surface treatment can range anywhere from about 10% to about 100% of the surface being treated. In an embodiment, the surface treatment ranges from about 25% to about 100% of the available surface. In an embodiment, the surface treatment ranges from about 50% to about 100% of the available surface.

(25) Colloidal systems in general, and aqueous colloidal silicas in particular, rely primarily upon electrostatic repulsion between charged silica particles to avoid unwanted or adverse phenomena such as particle agglomeration, flocculation, gelation and sedimentation. This electrostatic repulsion is easily disrupted in briny conditions typically found in subterranean formations. Furthermore, agglomeration/flocculation/gelation/sedimentation of colloidal silica and micellar solution containing colloidal silica in downhole applications would have the potential to damage the well or potentially plug the well entirely. Therefore, application of colloidal silica in downhole applications necessitates imparting brine resistant properties to colloidal silica and micellar solution containing colloidal silica before application. Standard tests for brine stability are disclosed herein.

(26) It is known to be advantageous in different applications to attach organic surface character to the surface of colloidal silica particles of aqueous solution. One such application is latex and emulsion polymerization chemistry, where the addition of surface treated colloidal silica can improve and modify the physical properties of the dried or cured latex coating. The addition of organic surface character to latex coatings can impart stability and shelf life to the colloidal silica component of a latex coating formulation, see previously cited U.S. Pat. No. 7,553,888.

(27) U.S. Pat. No. 7,553,888 “Aqueous Dispersion”, issued 30 Jun. 2009, describes and claims a method of producing an aqueous dispersion comprising mixing at least one silane compound and colloidal silica particles to form silanized colloidal silica particles and mixing said silanized colloidal silica particles with an organic binder to form the dispersion. The invention also relates to a dispersion obtainable by the method, and the use thereof.

(28) Other coating applications and coating formulations including both aqueous and nonaqueous systems can be similarly improved by the addition of organic surface character to colloidal silica, see U.S. Pat. No. 4,348,462, “Abrasion Resistant Ultraviolet Light Curable Hard Coating Compositions”, issued 7 Sep. 1982, describes and claims a radiation curable coating composition comprising (A) colloidal silica (B) acryloxy or glycidoxy functional silanes (C) non-silyl acrylates and (D) catalytic amounts of UV light sensitive cationic and radical type photoinitiators is provided, which cures to a transparent hard coating exhibiting improved abrasion resistance.

(29) It has been discovered that brine resistance of aqueous colloidal silica can be improved over untreated colloidal silica by addition of certain types of organic surface treatment. It was discovered that colloidal silica brine resistance could be further improved by surface treatment using mixtures of hydrophobic and hydrophilic surface treatment. It was furthermore discovered that use of these brine resistant colloidal systems in formulated micellar solution could improve performance in tests designed to model hydrocarbon recovery from subterranean formations.

(30) There are known ways to modify the surface of colloidal silica: 1. Covalent attachment of Inorganic oxides other than silica. 2. Non-covalent attachment of small molecule, oligomeric, or polymeric organic materials (PEG treatment, amines or polyamines, sulfides, etc.). 3. Covalent attachment of organic molecule including oligomeric and polymeric species: a. Reaction with organosilanes/titanates/zirconates/germanates. b. Formation of organosilanes/titanate/zirconate/germanate oligomers followed by reaction of these with surface of colloidal silica. c. Silanization followed by post-reaction formation of oligomeric/dendritic/hyperbranched/polymeric species starting from colloidal silica surface. d. Formation of oligomeric/dendritic/hyperbranched/polymeric silanes/zirconates/titanates followed by reaction to SiO.sub.2 surface.

(31) The silica particles included in the aqueous colloidal silica that is used in the brine resistant silica sol may have any suitable average diameter. As used herein, the average diameter of silica particles refers to the average largest cross-sectional dimension of the silica particle. In certain embodiments, the silica particles may have an average diameter of between about 0.1 nm and about 100 nm, between about 1 nm and about 100 nm, between about 5 nm and about 100 nm, between about 1 nm and about 50 nm, between about 5 nm and about 50 nm, between about 1 nm and about 40 nm, between about 5 nm and about 40 nm, between about 1 nm and about 30 nm, between about 5 nm and about 30 nm, or between about 7 nm and about 20 nm.

(32) In some embodiments, the silica particles have an average diameter of less than or equal to about 30 nm, less than or equal to about 25 nm, less than or equal to about 20 nm, less than or equal to about 15 nm, less than or equal to about 10 nm, or less than or equal to about 7 nm. In certain embodiments, the silica particles have an average diameter of at least about 5 nm, at least about 7 nm, at least about 10 nm, at least about 15 nm, at least about 20 nm, or at least about 25 nm. Combinations of the above-referenced ranges are also possible.

(33) Because of the nanometer diameters of the particles another word to describe the silica particles is by calling them nanoparticles.

(34) In certain embodiments, the colloidal silica is commercially available silica (e.g., hydrophobized silica). Commercially available colloidal silica including silica particles of the desired size that are suitable for use in the instant claimed invention are available from Nissan Chemical America Corporation, www.nissanchem-usa.com and Nalco Water, an Ecolab Company, www.ecolab.com/nalco-water.

(35) A common and economical way to add organic surface character to colloidal inorganic oxide particles is reaction of colloidal silica surfaces with organosilanes. Organosilanes of many types and variations can be obtained easily and cheaply as other large volume applications exist for these materials within industrial chemistry. While this method is cheap and simple in application to colloidal silica chemistry, there exist some limitations with-respect-to surface modification.

(36) Limitations include poor solubility of the starting organosilane in the dispersion solvent of colloidal silica which can result in incomplete surface functionalization or unwanted side reaction products. In other instances, successful surface reaction of colloidal silica with the wrong organosilane can result in loss of colloidal stability and agglomeration of the colloidal silica. In the situation of poor organosilane solubility, formation of organosilane oligomers before reaction with colloidal silica surfaces can be advantageous. Prehydrolysis and condensation of organosilanes to form polysiloxane oligomers is well known in the field of sol-gel science. This method is used to produce sol-gel type inorganic binders and primer coatings for sol-gel coating applications.

(37) In some instances, a superior surface functionalization can be achieved by initial oligomerization of organosilanes followed by reaction with colloidal silica. Prehydrolysis and condensation of organosilanes to produce oligomeric polysiloxane materials is a known method-mainly in coating science. See EP 1818693A1, “Anti-Reflective Coatings” by Iler, Osterholtz, Plueddemann. This European Patent Application was filed with a claim to a coating composition comprising (i) surface-modified nano-particles of a metal oxide, (ii) metal oxide-based binder, wherein the weight ratio of metal oxide in (i) to (ii) is from 99:1 to 1:1.

(38) In the case of aqueous colloidal silica, it is the observation of the inventor that surface reaction with organosilanes can have limitations due to solubility of organosilanes. Reaction of aqueous colloidal silica with organosilanes having too much hydrophobic character can be unsuccessful for two main reasons: 1. The relatively hydrophobic organosilane is not soluble enough in the aqueous system to effectively dissolve and react with the surfaces of aqueous colloidal silica. 2. The relatively hydrophobic organosilanes are able to dissolve in the aqueous system but after reaction to the colloidal silica surface renders the colloidal silica too hydrophobic to be stable in the aqueous system.

(39) One method to achieve improved reaction of hydrophobic organosilanes with aqueous colloidal silica is prehydrolysis. The prehydrolysis method is described in the reference document: “Silane Coupling Agents”, from Shin-Etsu Silicones, March 2015, available from www.shinetsusilicone-global.com/catalog/pdf/SilaneCouplingAgents_e.pdf). The prehydrolysis method relies on hydrolysis reaction of organosilane molecules together to form short polysiloxane type oligomeric chains of organosilane monomeric species. These prehydrolyzed species can display improved aqueous solubility. In the case of relatively hydrophobic organosilanes, prehydrolysis may improve initial water solubility but may not improve the ultimate stability of the reaction product of prehydrolyzed hydrophobic organosilane oligomers with aqueous colloidal silica, due to incompatibility of the final surface-functionalized silica due to too much hydrophobic character.

(40) To form brine resistant silica sols it is recommended to use the method of prehydrolysis of mixtures of hydrophobic silanes with hydrophilic silanes to effect rapid and convenient synthesis of brine-resistant aqueous colloidal systems having a combination of hydrophilic and hydrophobic character.

(41) The method of prehydrolysis of hydrophobic silanes with hydrophilic silanes before reaction with the surface of colloidal silica may allow for introduction of organosilanes molecules to aqueous colloidal silica surfaces that would not otherwise be possible due to excessive hydrophobic character in an aqueous colloidal system. In this way surface treated colloidal silica can be made as hydrophobic as possible, while still remaining stable and dispersed in an aqueous system.

(42) For example, in pure form, vinyltrimethoxysilane is sparingly soluble in water or aqueous colloidal silica. One skilled in the art may use methods or co-solvents to achieve solubilization of vinyltrimethoxysilane by itself into aqueous colloidal silica, but this application to colloidal silica has some difficulties. Vinyltrimethoxysilane, when reacted to the colloidal silica surface, by itself, will impart to the silica surface the nonpolar organic character of vinyl groups, which impart sufficient hydrophobic character to the particles as to destabilize the aqueous colloidal silica and cause the silica to agglomerate and precipitate out of solution or form a gel.

(43) It has been observed by the inventors that addition of certain types of organic surface character improve stability of aqueous colloidal silica in salt/brine solutions. Improvement of brine stability in colloidal silica systems can be found by using the aforementioned strategy of hydrophobic/hydrophilic organosilane combination and adding this combination to the surface of colloidal silica.

(44) One measure of hydrophobicity/hydrophilicity for organosilanes materials is surface tension or critical surface tension. Surface tension values for commercial organosilanes materials may be found in supplier literature materials (such as Gelest, www.gelest.com). Higher surface tension values indicate a more hydrophilic material, conversely lower surface tension values indicate a more hydrophobic material.

(45) As stated in the Arkles' article, “Hydrophobicity, Hydrophilicity and Silanes, Paint & Coatings Industry Magazine, October 2006 on page 3, “Critical surface tension is associated with the wettability or release properties of a solid. . . . Liquids with a surface tension below the critical surface tension (γc) of a substrate will wet the surface, . . . continued on page 4 . . . Hydrophilic behavior is generally observed by surfaces with critical surface tensions less than 35 dynes/cm (35 mN/m) . . . Hydrophobic behavior is generally observed by surfaces with critical surface tensions less than 35 dynes/cm (35 mN/m).”

(46) Surface tension values for commercial organosilanes materials may be found in supplier literature materials (such as Gelest, www.gelest.com). Higher surface tension values indicate a more hydrophilic material, conversely lower surface tension values indicate a more hydrophobic material.

(47) TABLE-US-00001 Critical Surface Tension (mN/m) Glycidoxypropyl Trimethoxysilane 42.5 Mercaptopropyl Trimethoxy silane 41 Phenyl Trimethoxy silane 40 Trimethoxy[2-(7-oxabicyclo[4.1.0]hept-3- 39.5 yl)ethyl]silane Methacryloxypropyl Trimethoxysilane 28 Vinyltrimethoxy Silane 25 Isobutyl Trimethoxy silane 20.9 ± 3.0* Hexamethyl Disiloxane 15.9 *source www.chemspider.com/Chemical-Structure.79049

(48) In terms of surface-treatment for colloidal silica a practical measure of hydrophilicity/hydrophobicity of an organosilanes is whether aqueous colloidal silica can be effectively treated by the organosilanes, and if the surface treated colloidal dispersion is stable in aqueous or semi-aqueous solution. After surface treatment with an organosilane or its oligomer upon an aqueous or semi-aqueous colloidal silica dispersion the hydrophilic surface treatment will allow for a stable dispersion, while an excessively hydrophobic surface treatment will show signs of instability such as gel or agglomeration.

(49) For this work, it has been found that optimal results are obtained when the hydrophilic organosilane monomer unit exhibits a critical surface tension in the range of 40-50 mN/m.

(50) For this work, it has been found that optimal results are obtained when the hydrophobic organosilane monomer unit exhibits a critical surface tension in the range of 15-39.5 mN/m.

(51) Oligomers prepared by prehydrolysis of organosilanes can be done by following this experimental procedure. Distilled water is brought to pH 3 by addition of hydrochloric acid. 10.0 grams of glycidoxypropyltrimethoxysilane, abbreviated “GPTMS” (sold under the tradename KBM 403 by Shin Etsu Corp.) and 1.0 gram of hydrophobic silane, including, but not limited to, one or more of methacryloxypropyl-trimethoxysilane and phenyltrimethoxysilane and isobutyltrimethoxysilane and hexamethyldisiloxane (sold under the tradename KBM 103 available from Shin Etsu Corp.) and 1.0 gram prepared pH 3 water are added to a 20 mL scintillation vial. A molar shortage of water is chosen to encourage linear polysiloxane oligomer formation. The combination is mixed by shaking the vial, resulting in a hazy mixture/emulsion which changes to clear and transparent upon standing for approximately 10 minutes. Transition from hazy to transparent is attributed to hydrolysis of Si—O—CH.sub.3 species to Si—OH species that are more compatible with water. The mixture is allowed to stand for a period of 30 minutes at room temperature to form organosilane oligomer species by condensation of Si—OH groups to form Si—O—Si polysiloxane bonds.

(52) Formation of polysiloxane oligomers is accompanied by an increase in viscosity as measured by Ubbeholde viscometer. Formation of polysiloxane oligomers is also verified by FTIR as measured by ThermoFisher Nicolet iS5 spectrometer. Oligomer formation is confirmed and monitored by reduction/loss of absorption peak at 1080 cm.sup.−1 assigned to Si—O—C stretching vibration and appearance and broadening of Si—O—Si absorption peaks in the 980 cm.sup.−1 region. Oligomer formation can also be confirmed by Gel Permeation Chromatography.

(53) This general method of prehydrolysis/condensation is followed for each combination of hydrophilic and hydrophobic organosilanes as well as comparative examples where oligomer formation was desired. Some organosilane combination preparations resulted in precipitates or gelled mixtures and were not used further.

(54) TABLE-US-00002 Ingredient in polysiloxane Preferred oligomer Low High Middle amount Amount of 9 parts 11 part 10 parts 10 parts glycidoxypropyl- trimethoxysilane in oligomer Amount of 1 part  3 parts  5 parts depends Hydrophobic Silane in oligomer

(55) It has furthermore been observed in model testing that crude oil can be more efficiently removed from downhole rock surfaces by using fluid systems formulated with such brine-resistant aqueous colloidal silica.

(56) In an embodiment, the oligomer includes organosilane monomer units.

(57) In an embodiment, the oligomer includes a first organosilane monomer unit and a second organosilane monomer unit that is different from the first organosilane monomer unit.

(58) In an embodiment, the oligomer includes at least a hydrophilic monomer unit and a hydrophobic monomer unit.

(59) In an embodiment, the oligomer includes at least a hydrophobic organosilane monomer unit and a hydrophilic organosilane monomer unit.

(60) In an embodiment, the hydrophilic organosilane monomer unit exhibits a critical surface tension in the range of from about 40 mN/m to about 50 mN/m.

(61) In an embodiment, the hydrophobic organosilane monomer unit exhibits a critical surface tension in the range of from about 15 mN/m to about 39.5 mN/m.

(62) In an embodiment, the oligomer is prepared from a solution that includes a molar ratio of a hydrophilic monomer unit to a hydrophobic monomer unit in the range of from 1:1 to 30:1.

(63) In an embodiment, the oligomer is prepared from a solution that includes a molar ratio of a hydrophilic monomer unit to a hydrophobic monomer unit in the range of from 2:1 to 15:1.

(64) In an embodiment, the oligomer is prepared from a solution that includes a molar ratio of a hydrophilic monomer unit to a hydrophobic monomer unit in the range of from 3:1 to 12:1.

(65) In an embodiment, the organosilane monomer includes a glycidyl group.

(66) In an embodiment, the aqueous colloidal silica is brine-resistant in both a 10 wt. % API Brine Solution and Artificial Seawater for at least 24 hours.

(67) In an embodiment, the oligomer includes 2-10 monomer units.

(68) In an embodiment, the oligomer includes 2-5 monomer units.

(69) In an embodiment, the fluid further comprises: a) one or more surfactants, b) one or more alcohols, c) one or more alcohol co-solvents; and d) water, with the amount of water selected such that the ratio of total water in the fluid to total terpene or terpenoid is at least about 15 to 1 and preferably is at least about 30 to 1.

(70) TABLE-US-00003 Fluid Amounts of Liquids Added*   30% Terpene or Terpenoid Oil Phase 30% Anionic Surfactant 10% isopropanol 30% Water

(71) The surfactants, alcohol and amount of water added to the formula is chosen such that the ratio of total water in the fluid to the amount of terpene is at least about 15 to 1, and more preferably is at least about 30 to 1.

(72) The amount of brine resistant surface functionalized aqueous colloidal silica depends upon the utility of the treatment fluid. Typically, the amount of water is reduced to accommodate the amount of aqueous colloidal silica.

(73) In an embodiment, the aqueous colloidal silica has silica particles with a surface that is functionalized with at least one polysiloxane oligomer.

(74) In an embodiment, the polysiloxane oligomer comprises Ingredient A and Ingredient B, wherein Ingredient A is glycidoxypropyltrimethoxysilane and Ingredient B is selected from the group consisting of one or more of methacryloxypropyltrimethoxysilane, isobutyltrimethoxysilane, vinyltrimethoxysilane, trimethoxy[2-(7-oxabicyclo[4.1.0]hept-3-yl)ethyltrimethoxysilane and hexamethyldisiloxane.

(75) In an embodiment, the fluid comprises: (a) a terpene-based oil phase that includes less than about 20 wt. % d-limonene, (b) an anionic surfactant selected from the group consisting of alkyl olefin sulfonate surfactants; (c) an alcohol selected from the group consisting of C.sub.1-C.sub.6 alcohols; (d) an alcohol cosolvent; (e) water; with the amount of water selected such that the ratio of total water in the fluid to total terpene or terpenoid is at least about 15 to 1 and preferably is at least about 30 to 1; and (f) a brine resistant surface functionalized colloidal silica.

(76) In an embodiment, the fluid comprises: (a) a terpenoid based oil phase, (b) an anionic surfactant selected from the group consisting of alkyl olefin sulfonate surfactants; (c) an alcohol selected from the group consisting of C.sub.1-C.sub.6 alcohols; (d) an alcohol cosolvent; (e) water; and (f) a brine resistant surface functionalized colloidal silica.

(77) In certain embodiments, the following ingredients are present in the treatment fluid.

(78) TABLE-US-00004 Mass Component (g) VertecBio DLR 3 AOS-40 7.5 Ethylan 1206 2 Isopropanol 1 Water 2.5 Total 16 VertecBio DLR 3 AOS-40 7.5 Isopropanol 1 Water 2.5 2-Ethyl-1-hexanol 1 Total 15
In Other Embodiments, the Following Ingredients are Present:

(79) TABLE-US-00005 Amount Materials: (kg): % 1 VertecBio DLR 0.315 1.10% 2 VertecBio Gold 3.61 12.65% 3 AOS-40 12.26 42.96% 4 MC-6100 3.50 12.27% 5 IPA 3.90 13.67% 6 DI H2O 2.95 10.34% 7 E11126 2.00 7.01% 28.535 100.00%
E11126 is a brine-resistant silicasol made from ST-025, available from Nissan Chemical America Corp. and GPTMS Glycidoxypropyltrimethoxysilane
In other embodiments, these ingredients are present in the treatment formulation.

(80) TABLE-US-00006 Component Mass (g) Mass (g) Mass (g) VertecBio DLR 0.16 0.12 0.08 VertecBio Gold 1.84 1.38 0.92 AOS-40 7.5 7.5 7.5 Ethylan 1206 2 2 2 Isopropanol 2 2.5 3 Water 2.5 2.5 2.5 Total 16 16 16
In other embodiments, the named ingredients are present in the treatment formulation.

(81) TABLE-US-00007 Component Mass (g) VertecBio DLR 0.16 VertecBio Gold 1.84 AOS-40 6.25 Ethylan 1206 1.66 Isopropanol 2 Water 1.5 E11126 colloidal 1.9 silica surface treated

EXAMPLES

(82) Surface functionalization of Colloidal silica dispersions using polysiloxane oligomer preparations is conducted as follows:

(83) A solution of colloidal silica is prepared for surface functionalization by adding 59.28 g ST-32C Nissan Chemical America Corp. to a 250 glass vessel and further adding 27.98 g distilled water, and 9.85 g Ethylene Glycol cosolvent (Sigma Aldrich corp.). This mixture is brought to 50° C. while mixing by magnetic stirring with a magnetic stir bar & stir plate.

(84) A portion of silane surface treatment (hydrophilic silanes, mixture of hydrophilic and hydrophobic silanes, or polysiloxane oligomer preparation) (2.9 grams) is placed in an addition funnel and then added dropwise to the stirring colloidal silica mixture. After the polysiloxane oligomer preparation solution addition is finished the solution is allowed to react at 50-55° C. for a period of 3 hours. Each surface functionalization reaction is performed with these component proportions. Some example combinations resulted in precipitates or gelled colloidal silica/oligomer mixtures and are not evaluated further.

(85) Preparation of E11125 Surface Functionalized Colloidal Silica

(86) A Polysiloxane oligomer premix was prepared from 10 parts glycidoxypropyltrimethoxysilane, 5 parts vinyltrimethoxysilane, and 1 part pH3 water (prepared from distilled water and 10% HCl brought to pH 3 using a calibrated pH meter) by mixing these components and allowing the mixture to react at room temperature for a period of 30 minutes. A solution of colloidal silica is prepared for surface functionalization by adding 59.28 g ST-32C alkaline colloidal silica from Nissan Chemical America Corp. to a 250 glass vessel and further adding 27.98 g distilled water, and 9.85 g Ethylene Glycol cosolvent (Sigma Aldrich corp.). This mixture is brought to 50° C. while mixing by magnetic stirring with a magnetic stir bar & stir plate.

(87) A portion of the GPTMS/VTMS Polysiloxane oligomer premix (2.9 grams) is placed in an addition funnel and then added dropwise to the stirring colloidal silica mixture. After the polysiloxane oligomer preparation solution addition is finished the solution is allowed to react at about 50° C.-55° C. for a period of 3 hours.

(88) Preparation of E11126 Surface Functionalized Colloidal Silica

(89) A solution of colloidal silica is prepared for surface functionalization by adding 52.68 g ST-025 acidic colloidal silica available from Nissan Chemical America Corp. to a 250 glass vessel and further adding 36 g distilled water, and 8 g Ethylene Glycol cosolvent (Sigma Aldrich corp.). This mixture is brought to 50° C. while mixing by magnetic stirring with a magnetic stir bar & stir plate.

(90) Glycidoxypropyltrimethoxysilane (3.2 grams) is placed in an addition funnel and then added dropwise to the stirring colloidal silica mixture. After the monomeric organosilane addition is finished the solution is allowed to react at from about 50° C.-55° C. for a period of 3 hours.

(91) Brine Resistance Testing:

(92) Preparation of Brines for testing: A 10 wt % API Brine solution is prepared by dissolving 8 wt % NaCl (SigmaAldrich) and 2 wt % CaCl.sub.2) (Sigma Aldrich) in distilled water. Artificial seawater is prepared by dissolving Fritz Pro Aquatics RPM Reef Pro Mix (Fritz Industries, Inc.) at 6 wt % in distilled water.

(93) Testing for Brine resistance: Prepared silicasol examples are evaluated by placing 1 gram of example silica sol into 10 grams of Brine. Stability tests are performed at standard brine exposure periods of 10 minutes and 24 hours, observations being recorded at these times. Silica sol solutions that are stable to Brine exposure will remain clear and transparent/opalescent while unstable examples become visibly hazy and opaque after brine exposure. The following table summarizes the results.

(94) TABLE-US-00008 Silica sol Brine resistance with Result after Oligomer Silica sol brine artificial sea- undergoes surface resistance with water after 10 Oligomer Oligomer Oligomer functionalization 10% API Brine minutes/after Example Ingredients Ingredients Result with colloidal silica after 10 minutes 24 hours 1 1 part 10 parts slightly transparent/opalescent Passed Passed/Passed methacryloxypropyl- glycidoxy viscous and appeared stable trimethoxysilane propyl- oligomer trimethoxy solution silane 2 2 parts 10 parts slightly transparent/opalescent Passed Passed/Passed methacryloxypropyl- glycidoxy viscous and appeared stable trimethoxysilane propyl- oligomer trimethoxy solution silane 3 1 part 10 parts slightly transparent/opalescent Passed Passed/Passed isobutlytrimethoxy- glycidoxy viscous and appeared stable silane propyl- oligomer trimethoxy solution silane 4 2 parts 10 parts slightly transparent/opalescent Stable after 10 Stable/Stable isobutyltrimethoxy- glycidoxy viscous and appeared stable minutes/Stable silane propyl- oligomer after 24 hours trimethoxy solution silane 5 1 part 10 parts slightly transparent/opalescent Stable after 10 Stable/Stable isobutyltrimethoxy- glycidoxy viscous and appeared stable minutes/Stable silane propyl- oligomer after 24 hours trimethoxy solution silane 6 5 parts 10 parts slightly transparent/opalescent Stable after 10 Stable/Stable isobutyltrimethoxy- glycidoxy viscous and appeared stable -had minutes/Stable silane propyl- oligomer some microgel formation after 24 hours trimethoxy solution observed at the margin silane of the reaction vessel. 7 2 parts 10 parts slightly transparent/opalescent Stable after 10 Stable/Stable hexamethyldisiloxane glycidoxy viscous and appear stable minutes/Stable propyl- oligomer after 24 hours trimethoxy solution silane

(95) The above Examples are examples of surface treated colloidal silica that would be effective in the hydrocarbon formation treatment micellar solution of the instant claimed invention. The examples of the instant claimed invention are then formulated into micellar solution that will be suitable for injection into underperforming hydrocarbon formations.

(96) Examples of Hydrocarbon Formation Treatment Micellar Solution

(97) TABLE-US-00009 Weight % of Each Fluid 1 (SG = 0.970) (g) Component Identity VertecBio DLR 3 20.00 Dipentene mixture, Terpene based oil phase AOS40 7.5 50.00 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Isopropanol 1 6.67 Isopropanol, water soluble cosolvent Water 2.5 16.67 Water 2-Ethyl-1-Hexanol 1 6.67 Alcohol cosolvent, low polarity less water soluble Total 15 100

(98) TABLE-US-00010 Weight % of Each Fluid 2 (SG = 0.987) (g) Component VertecBio DLR 3 18.75 Dipentene mixture, Terpene based oil phase AOS40 7.5 46.875 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 2 12.5 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer Isopropanol 1 6.25 Isopropanol, water soluble cosolvent Water 2.5 15.625 Water Total 16 100

(99) TABLE-US-00011 Weight % of Each Fluid 2a (g) Component VertecBio DLR 3 19.83 Dipentene mixture,Terpene based oil phase AOS40 5 33.06 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 1.33 8.79 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer IPA 1 6.61 Isopropanol, water soluble cosolvent Water 1 6.61 Water E11125 3.796 25.10 ST-32C colloidal silica surface treated with GPTMS + Vinyl Trimethoxysilane oligomer Total 15.126 100.00

(100) TABLE-US-00012 Weight % of Each Fluid 2b (g) Component VertecBio DLR 3 19.83 Dipentene mixture, Terpene based oil phase AOS40 5 33.06 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 1.33 8.79 Nonionic surfactant-Ethylene Oxide/Propylene Oxide copolymer IPA 1 6.61 Isopropanol, water soluble cosolvent Water 1 6.61 Water E11126 3.796 25.10 Surface treated acidic colloidal silica, 10-15 nm Total 15.126 100

(101) TABLE-US-00013 Weight % of Each Fluid 2c (g) Component VertecBio DLR 3 19.60 Dipentene mixture, Terpene based oil phase AOS40 6.25 40.83 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 1.66 10.84 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer Isopropanol 1 6.53 Isopropanol, water soluble cosolvent Water 1.5 9.80 Water E11125 1.898 12.40 ST-32C surface treated with GPTMS + Vinyl Trimethoxysilane oligomer Total 15.308 100

(102) TABLE-US-00014 Weight % of Each Fluid 2d (g) Component VertecBio DLR 3 19.60 Dipentene mixture, Terpene based oil phase AOS40 6.25 40.83 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 1.66 10.84 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer Isopropanol 1 6.53 Isopropanol, water soluble cosolvent Water 1.5 9.80 Water E11126 1.898 12.40 Surface treated acidic colloidal silica, 10-15 nm Total 15.308 100
Hele-Shaw Cell Test Showed Micellar Solution 1 and 2 to have Very Similar Oil Recovery to Control CNF

(103) TABLE-US-00015 Silurian Amott Dolomite Cell Cores Testing Dry Imbibed Oil Extracted Recovered % Average Fluid Core Weight Weight Weight Core Weight Oil Recovery Recovery % Fluid 1 1 66.32 68.17 1.85 67.99 0.18 9.73 Fluid 1 2 64.93 66.67 1.74 66.55 0.12 6.9 Fluid 1 3 63.94 66.08 2.14 65.89 0.19 8.88 8.5 Fluid 2 4 61.55 64.21 2.66 63.89 0.32 12.03 Fluid 2 5 65.46 66.64 1.18 66.75 −0.11 −9.32 Fluid 2 6 65.65 66.48 0.83 66.93 −0.45 −54.22 −17.17 (anomalous result due to low rock porosity) Control 7 64.08 65.74 1.66 65.41 0.33 19.88 CNF* Control 8 60.17 63.07 2.9 62.57 0.5 17.24 CNF Control 9 62.41 64.87 2.46 64.5 0.37 15.04 17.39 CNF *Complex Nano Micellar solution (CNF): are commercially available micellar solution prepared with D-Limonene as oil-phase in combination with surfactants, cosolvents, and water.

(104) TABLE-US-00016 Weight % of Each Fluid 3 (g) Component VertecBio DLR 0.16 1 Dipentene mixture, Terpene based oil phase VertecBio Gold 1.84 11.5 Methyl Soyate oil phase AOS40 7.5 46.875 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 2 12.5 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer IPA 2 12.5 Isopropanol, water soluble cosolvent Tap Water 2.5 15.625 Water Total 16 100

(105) TABLE-US-00017 Weight % of Each Fluid 4 (g) Component VertecBio DLR 0.16 1.05 Dipentene mixture, Terpene based oil phase VertecBio Gold 1.84 12.02 Methyl Soyate oil phase AOS40 6.25 40.82 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 1.66 10.84 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer IPA 2 13.06 Isopropanol, water soluble cosolvent Tap Water 1.5 9.80 Water E11126 1.9 12.41 Surface treated acidic colloidal silica, 10-15 nm Total 15.31 100

(106) TABLE-US-00018 Weight % of Each Fluid 3a (g) Component VertecBio DLR 0.12 0.75 Dipentene mixture, Terpene based oil phase VertecBio Gold 1.38 8.625 Methyl Soyate oil phase AOS40 7.5 46.875 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 2 12.5 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer IPA 2.5 15.625 Isopropanol, water soluble cosolvent Tap Water 2.5 15.625 Water Total 16 100

(107) TABLE-US-00019 Weight % of Each Fluid 3b (g) Component VertecBio DLR 0.08 0.5 Dipentene mixture, Terpene based oil phase VertecBio Gold 0.92 5.75 Methyl Soyate oil phase AOS40 7.5 46.875 Alkyl Olefin Sulfonate, anionic surfactant 40% actives Ethylan 1206 2 12.5 Nonionic surfactant - Ethylene Oxide/Propylene Oxide copolymer IPA 3 18.75 Isopropanol, water soluble cosolvent Tap Water 2.5 15.625 Water Total 16 100

(108) TABLE-US-00020 Boise Sand- Ammot stone Cell Cores Testing Dry Imbibed Oil Extracted Recovered % Average Fluid Core Weight Weight Weight Core Weight Oil Recovery Recovery % 3 1 43.61 50.3 6.69 49.53 0.77 11.51 3 2 45.93 52.26 6.33 50.61 1.65 26.07 3 3 45.4 51.82 6.42 50.62 1.2 18.69 18.76 4 4 44.95 51.21 6.26 47.41 3.8 60.7 4 5 45.74 51.98 6.24 48.2 3.78 60.58 4 6 42.55 49.06 6.51 44.59 4.47 68.66 63.31 Control 7 46.02 52.19 6.17 48.78 3.41 55.27 CNF* Control 8 42.76 49.26 6.5 45.44 3.82 58.77 CNF* Control 9 43.21 49.92 6.71 49.13 0.79 11.77 41.94 CNF* *Complex Nano Micellar solution (CNF): are commercially available micellar solution prepared with D-Limonene as oil-phase in combination with surfactants, cosolvents, and water.

(109) TABLE-US-00021 Example 5A Mass Component (g) VertecBio DLR 3 AOS-40 7.5 Ethylan 1206 2 Isopropanol 1 Water 2.5 Total 16 Example 5B VertecBio DLR 3 AOS-40 7.5 Isopropanol 1 Water 2.5 2-Ethyl -1 -hexanol 1 Total 15

Example 6—Mixture of Comparative Examples and Working Examples

(110) TABLE-US-00022 Mass Mass Mass Mass Mass Component (g) (g) (g) (g) (g) VertecBio DLR 0.24 0.2 0.16 0.12 0.08 VertecBio Gold 2.76 2.3 1.84 1.38 0.92 AOS-40 7.5 7.5 7.5 7.5 7.5 Ethylan 1206 2 2 2 2 2 Isopropanol 1 1.5 2 2.5 3 Water 2.5 2.5 2.5 2.5 2.5 Total 16 16 16 16 16 Worst Better VertecBio DLR 0.16 0.16 0.12 VertecBio Gold 1.84 1.84 1.38 AOS-40 5 6.25 6.25 Ethylan 1206 1.33 1.66 1.66 Isopropanol 2 2 2.5 Water 1 1.5 1.5 E11125 (ST-32C colloidal 3.8 1.9 1.9 Silica, surface treated with GPTMS + Vinyl Trimeth- Oxysilane oligomer Worst Better 1% Worse than Better Ingredients VertecBio DLR 0.16 0.12 VertecBio Gold 1.84 1.38 AOS-40 6.25 6.25 Ethylan 1206 1.66 1.66 IPA 2 2.5 Tap Water 1.5 1.5 E11126 1.9 1.9 Worse
In certain embodiments, Example 7, the following ingredients are present in the treatment fluid.

(111) TABLE-US-00023 Component Mass (g) VertecBio DLR 3 AOS-40 7.5 Ethylan 1206 2 Isopropanol 1 Water 2.5 Total 16 VertecBio DLR 3 AOS-40 7.5 Isopropanol 1 Water 2.5 2-Ethyl-1-hexanol 1 Total 15
In other embodiments, Example 8, these ingredients are present in the treatment formulation.

(112) TABLE-US-00024 Component Mass (g) Mass (g) Mass (g) VertecBio DLR 0.16 0.12 0.08 VertecBio Gold 1.84 1.38 0.92 AOS-40 7.5 7.5 7.5 Ethylan 1206 2 2 2 isopropyl alcohol 2 2.5 3 Water 2.5 2.5 2.5 Total 16 16 16
In other embodiments, Example 9, the named ingredients are present in the treatment formulation.

(113) TABLE-US-00025 Component Mass (g) VertecBio DLR 0.16 VertecBio Gold 1.84 AOS-40 6.25 Ethylan 1206 1.66 Isopropyl alcohol 2 Water 1.5 E11126 1.9

(114) In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e. to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

(115) While several embodiments of the present invention have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the functions and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the present invention. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. Those skilled in the art will recognize or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the scope of the present invention. All patents, patent applications, and references cited in any part of this disclosure are incorporated herein in their entirety by reference.