CA1152854A - Micellar solutions of thin film spreading agents comprising an acylated polyether polyol - Google Patents

Abstract

ABSTRACT OF THE INVENTION

The invention provides a homogeneous, micellar solution of a water-insoluble thin film spreading agent comprising:
(a) from between about 5% and about 75% by weight of an acyated polyether polyol; (b) from between about 2% and about 30% by weight of a hydrotropic agent; (c) from between about 2% and about 30% by weight of an amphipathic agent; and (d) from between about 15% and about 90% by weight of water.

Description

359L' BACKGROUND OF THE INVENTION
1. ~13LD 0~ tlO~: The invention relates to a new and improved micellar solution of a thin film spreading agent comprising an acylated polyether polyol which is particularly useful for break-ing or preventing petroleum emulsions. More specifically, the invention rela~es to a composition in which water replaces all or a substantial part of the organic solvents formerly required for preparation of liquid solutions oE this interfacially active compound.

2. DESCRIP~o~ IO~ A~l: One of the principal uses of the presen~ composition is in the breaking of petroleum emulsions to permit thP separation thereof into two bulk phases. Uuch of the crude petroleum oil produced throughout the world is accompanied by some water or brine which originates in or adjacent to the geological formation from which the oil is produced. The amount of aqueous phase accompanying the oil may vary~from a trace to a very large percentage o~ the total fluid produced. ~ue to the natural occur-rence in most petrolèum of oil-soluble or dispersible emulsifying ~, agents, much of the aqueous phase produced with oil is emulsified therein, forming sta~le water-in-oil emulsions.~
The literature contains numerous reerences to such emulsions, the problems resul~ing from their occurrence, and the methods employed to break them and separate sal ble petroleum. See, for example, "The Technology of Resolving Petroleum Emulsions" by L. T. Monson and R. W. Stenzel, p. 535 et seq in Colloid Chemistry Vol. VI, Ed. by Jerome Alexander, Rheinhold Publishing Corp., New York (1946) and "Interfacial Filrns Affecting the Stability of Petroleum Emulsions" by Chas. M. Blair, Jr. in C ~ d Industry (London), p. 538 et seq (1960).
Early demulsifiers used to resolve petroleum emulsions were water-soluble soaps, Twitchell reagents, and sulfonated glycerides.
These products were readily compounded with water to form easily ~' 8~ .
pumpable liquids and were conveniently applied by pumping into flow lines at the well head or by washing down the casing annulus with water to commingle with well fluids prior to their flow to tha surface. These products, however, were effective only at relatively high concentrations and their use added substantially to the cost of production.
Some time ago, it was discovexed that certain lightly sul-fonated oils, acetylated caster oils and various polyesters, all of which were insoluble in water but soluble in alcohols and aromatic hydrocarbons, were much more effective in breaking emulsions.
Accordingly, esqentially all commercial demulsifier development has led to production of agents which are insoluble in both water and petroleum oils and have other properties to be described below which cause them to spread at oil-water interfaces to form very thin, mobile films which displace any emulsifying agent present in the oil to allow coa1escence of dispersed water droplets. Generally, such interfacially active compounds are hereafter referred to as Thin Film Spreading Agents, or "TF5A's". In the past, these have had to be compounded with and dissolved in alcohols or highly aromatic hydrocarbon solvents in order to produce readily applied liquid compositions. A wide variety of such compositions are required to trea~ the many different emulsions encountered throughout the world.
While present TFSA compositions are highly effective, being, perhaps, up to fifty to a hunared times more effective per unit volume than the original water-soluble demulsifiers, they suffer serious practical deficiencies because of their solubility charac-teristics. For example, alcohols and the aromatic hydrocarbons, which are required for preparation of liquid, pumpable compositions, are quite expensive, today approaching in cost that of the active demulsifier ingredient itself. Further, such solvents are flammable ~L5;~1~54 and thus create safety problems and entail more expense in shipping, storing and use. The low flash point flammability can be improved by using high boiling aromatic solvents, but these are increasingly rare, expensive and dangerous from the standpoint of carcinogenicity and dermatological effects.
Still further, present demulsifiers cannot generally be used in a subterranean oil or gas well, injection well, or the like, since they cannot be washed down with either water (or brine) or a portion of the produced oil, and, being viscous liquids which are required in very small amoun~s, they cannot be reliably and con-tinuously delivered several thousand feet down at the fluid level in a typical well without use of elaborate and expensive dalivery means.
Other applications of TFSA compositions would be facili-tated if they were readily soluble or dispersible in water. For example, much heavy, viscous oil is p~oduced in the United States by s~eam in~ection procedures. Typically, we~ steam is injec~ed into the oil producing strata for several weeks in order to heat the oil, lower its vlscosity and increase reservoir energy. Steam 20 iniection i8 then stopped and oil is flowed or pumped from the bore hole which was used for steam injection. Much of the water resulting from condensation o~ the steam is also produced with the oil in emuisified form. Since emulsions are more viscous than the external phase at the same temperature, and thus create increased resistance to flow, productivity of the steamed wells can be improved by injecting a water-soluble demulsifier into the wet -steam during the ste~m injection period to prevent emulsion formation. See, for example, U.S. Patent 3,396,792, dated April 1, 1966, to F. D. Muggee. At present, the requirement of water solu-bility seriously limits the choice of demulsifiers for use insteam or water injection to the relatively inefficient compositions.

~l~Z85~
As disclosed in my co-pending Canadian applications, Serial Number 353,251, filed ~une 3, 1980 and entitled "Method Of Recovering Petroleum From A Subterranean Reservoir Incor-porating A Polyether Polyol", and Serial Number 353,233, filed June 3, 1980, and entitled "Method of Recovering Petroleum From A Subterranean Reservoir Incorporationg Polyepo~ide Con-densates Of Resinous Polyalkylene Oxide Adducts And Polyether Polyols", TF5A's are useful in processes for enhanced recovery of petroleum. Used in such processes involving displacement of residual oil by aqueous solutions, polymer solutions and other aqueous systems, these agents act to increase the amount of oil recovered. Such action possibly arises from their abil-ity to further water wetting of reservoir rock, lessen the vis-cosity of the oil-water interfacial layer and promote coales-cence of dispersed droplets of either water or oil in the other , phase.
By use of the present aqueous micellar solutions, the in-troduction of TFSA into aqueous displacement or flooding fluids is greatly facilitated. In addition, the present micellar solutions, per se, or in combination with other components, can be used as the flooding agent or as a pretreating bank or slug ahead of other aqueous fluids.
other applications for the present TFSA micellar solutions include their use as flocculation aids for finely ground hema-tite and magnetite ores during the desliming step of ore bene-ficiation, as additives for improviny the oil removal and de-tergent action of cleaning compositions and detergents designed for use on polar s~ ~
materials, for the improvement of solvent extraction processes such as those used in ex~raction of antibiotic products from aqueous fermentation broths with organic solvents, for the improve-ment of efficiency and phase separation in the purification and concentration of metals by solvent extrac~ion with organic solutions of metal complex-forming agents, and as assistants to improve the wetting and dying of natural and synethetic fibers and for other processes normally involving the interface between surfaces of differing polarity or wetting characteristics.

SUMMARY OF THE INVENTION
A primary object of the present invention is to provide aqueous, liquid compositions of these TFSA's having new and useful characteristics which allow production of: petxoleum emulsion breakers and emulsion preventing compositions free or relatively free of highly flammable and environmentally objectionable aromatic hydrocarbons; compositions having a comparati~ely low cost; compo-sitions which are soluble or dispersible in water and which, there-fore, can often be applied by mor~ effective methods than can existing produc~s; compositions which can be used in enhanced recovery operations such as steam flooding and aqueous medium flooding where present products cannot be readily applied; and compositions which can be Gompounded with water-soluble reagents of other types, such as corrosion inhibitors, wetting agents, scale inhibitors, biocides, acidsl etc., to provide multipurpose compounds for use in solving many oil well completion, production, trans-portation and refining problems.
In accordance with the present invention, these aims are accomplished by means of amphipathic agents which are capable of forming micellar solutions and which by this mechanism or other undefined actions, combined with those of a second essential 8~4 component which will be referred to as a hydrotropic agent, are able to form homogeneous aqueous solutions containing a relatively wide range of concentrations of TFSA.

DESCRIPTION OF T~IE PREFERRED EMBODIMENTS
The TFSA compositions of the present invention can be broadly categorized by the following general characteristics:
1. Solubility in water and isooctane at about 25C
is less than about 1% by volume;
2. Solubility parameter at about 25C is in the range of from between about 6.8 to about 8.5, with a majority in the range of from between 7.0 and about 7.9; and ; 3. Spread at the interface between white~ refined mineral oil and distilled water to~form films having a cal-culated thickness~no greater~than about 20 Angstroms at a spreading pressure of about 16 dynes per cm.
TFSA compositions having these properties are generally organic polymers or semi-polymers having molecular weights ranging from about 2,000 to about 100,000 and having structures containing a multiplicity of distributed hydrophilic and hydrophopic moieties arranged in linear or planar arrays which make them surface active and lead to their absorption at oil-water interfaces to form very thin films.
Unlike most commonly encountered surface-active compounds, the present TFSA appears to be lncapable of forming a micelle in either oil or water. The distributed and alternating occurrence of polar and nonpolar or hydrophilic and hydrophobic groups In the molecule apparently prevents the kind of organization required for micelle formation and thus impairs dispersion or solution in either water or low polarity organic solvents.
The TFSA's useful in the present invention have the previously recited properties:

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1. The solubility in Water and in lsooctane a* about :~.
Solubility tests may be run by placing~a 1 ml sample tor the weight of solid product calculated to have a volume of 1 ml) in a graduated cylinder of the type which may be closed with a ground glass stopper.
Thereafter place 99 ml of water in the cylinder, close, place in a 25C water bath until thermal equilibrium is reached, and remove from the bath and shake vigorously for one minute. Return the sample to the bath for five minutes and then repeat the shaking procedure. Finally, return the sample to the bath and allow it to stand quletly for one hour. The cylinder contents should be carefully examined and any cLoudiness or opacity of the liquid phase or the appearance of any sediment or un~
dissolved material in the cyLinder noted, thus indicat-ing that the sample satisfied the requirement for insolubility in water.
Isooctane solubility is determined similarly by substituting this hydrocarbon fox the water used above.
2. The Solubility ~arameter (S.P.) at about 25C is from b'etween about'6.9 ahd about 8.5, inclusive , ~. . ~ ~
Methods of determination of solubility parameter are disclosed in Joel H. Hildebrand, i'The Solubility of Nonelectrolytes", Third Edition, pgs. 425 et seq~
However, a simplified procedure, sufficiently accurate for qualification of ~ useful TFSA composition may be utilized. Components of a give solubility parameter are generally insoluble in hydrocarbon (non-hydrogen-bonding) solvents ha~ing a lower solubility parameter than themselves. Therefore, the present composition ~5Z8S~ .

should be insoluble in a hydrocarbon solvent of a solubility parameter of about 6.8. Since the solu-bility parameter of mixtures of solvents is an additive function of volume percentage of components in the mixture, test solutions of the desired solubility parameters may be easily prepared by blending, for example, benzene (S.P. 9.15) and isooctane (S.P. 6.85) or perfluoro-n-hep~ane (S.P. 5.7).
A mixture of about 72 parts of benzene with about ; 10 28 paxts of isooctane will provide a solvent having a solubility parameter of about 8.5 at room temperature (about 25C). Perfluoro-n-heptane has a solubility parameter of about 5.7 at 25C, so a mixture of 68 parts of this solven~ with 32 parts of benzene provides a solvent wlth a solubility~parameter of about 698, or isooctane of a solubility parameter 6.85 may be used.
When 5 ml of th~ TF9A are mixed with 95 ml of an 8.5~solubilitv parameter ~oIvent at room temperature, a clear solution should result. When 5 ml of TFSA is mixed with a 6.85 solubility parameter svlvent, a cloudy mixture or one showing phase separation should , result. Solvent mixtures have a solubility parameter between about 7.0 and about 7.9 may be prepared as described above and utilized in a similar test procedure.
In interpreting the solubility parameter and other tests, it should be recognized that the TFSA consists not of a single material or compound but a cogeneric mixture of products containing a range of products of molecular weights distributed around the average molecular weight and even containing small amounts of the starting compounds employed in the synthesis.
As a xesult, in running solubility and solubility parameter tests, very slight appearances of cloudi-ness or lack of absolute clarity should not be inter-preted as a pass or a failure to pass the criteria.
The intent of the test is to ensure that the bulk of the cogeneric mixture, i.e., 75~ or more, meets the requirement. When the result is in doubt, the solu-bility tests may be run in centrifuge tubes allowing subsequent rapid phase separation by centrifuging, after which the separated non-solvent phase can be removed, any solvent contained in it can be evaporated, and the actual weight or volum~ of separated phase can be determined.

3. The TFSA should spread at tha interface between diskilled water _hd refined mlneral oi~ to form fi-lms with thick-ness~ no g-reatex than about 20 Angstroms (0 0020 micro-meter) at a film Pressure of about 16 dYnes ~er cm (0.016 Newton Per meter) ~ Suitable methods of determining film pressure are disc1Osed~i~ N. K. Adam, "Physics and Chemistry of ' Surfaces", Third Edition, ~ ~s, London, 1941, pgs. 20 et seq, and C. M. Blaix, ~r., "Interfacial Films Affecting The Stability of Petroleum Emulsions", Chemistry and_Industr~ (London), 1960, pgs.
538 et seq. Film thickness is calculated on the assump-tion that all of the TFSA remains on the area of inter-~ace between oil and water on which the product or its solution in a volatile solvent has been placed. Since spreading pressure is numerically equal to the change in interfacial tension resulting from spreading of a film, it is conveniently determined by making interfacial ~28S~ .

tension measurements before and after adding a known amount of TFSA to an interface of known area.
Alterna~ively, one may utilize an interfacial film balance of the Langmuir type such as that described by J. H. Brooks and B. A. Pethica, Transactions of the Faraday Soc ~ (1964), p.. 20 et seq, or other methods which ha~e been qualified for such interfacial spread-ing pressure determinations.
In determining the interfacial spreading pressure of the TFSA products, I prefer to use as the oil phase a fairly~avallahle~and reproducible oil such as a clear, refined~mineral oil. Such oils are derived from petroleum and have been treated with sulfuric acid and other agents:to remove nonhydrocarbon and :
aromatic constituents. Typical of such oils is "Nujol", distributed~by Plough, Inc. This oil ranges in density :
from about 0.85 to 0~89 and usually has a solubility parameter between about 6.9 and about 7.5. Mumerous similar oils of greater or smaller density and viscosity are commonly available from c~hemical supply houses and pharmacies.
Other essentially aliphatic or naphthenic hydro-carbons of low vola ility are equally usable and will yield similar values of spreading pressure. Suitable hydrocarbon oils appear in commercial trade as refined "white oils", "textile lubricants", "paraffin oil", and the like. Frequently, they may contain very small quantities of alpha-tocopherol (Vitamin El or similar antioxidants which are oil-soluble and do not interfere with ~he spreading measurements.

5~ .

While the existence of micelles and o oily or aqueous micellar solutions have been known for some time (see, e.g., "Surface Activity", Moilliet, Collie and Black, D. Van Nostrand & Co., New York (1961)) and are probably involved in many opera-tions involving detergency where either oily (nonpolar) or earthy (highly polar) soil particles are to be removed, their utility in cooperation with hydrotropic agents for the present purposes is an unexpected and unpredictable discovery.
In U.S. Patent No. 2,356,205, issued August 22, 1944, to Chas. M. Blair, Jr. & Sears Lehman, Jr., a wide variety of micellar solutions designed to dissolve petroleum oils, bitumen, wax, and other relatively nonpolar compounds are described for purposes of cleaning oil forma~ion faces and for effecting enhanced recovery of petroleum by solution thereof. ~t this early date~ however, the use of micellar principles was not contemplated for the preparation of solutions of ~he relatively high mQlecular weight demulsifiers.
However, some of the principles disclosed in the above patent, omitting the main objective therein of dissolving rela-tively large amounts of hydrocarbons, chlorinated hydrocarbons, and the like, are applicable to preparation of the present compositions.
The four necessary components of the micellar solutions of TFSA are:
1. A rnicelle-~ormin~ amphipathic agent. Such may be anionic, cationic, or nonionic and, if anionic or cationic, may be either in salt form or as the free acid or free base or mixtures thereof.
2. A hydrotro~ic a~ent. This is a small to medium mole-cular weight semi-polar compound containing oxygen, nitrogen or sulfur and capable of forming hydrogen bonds.

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It is believed that such agents cooperate in some manner with the amphipathic agent to form clear or opalescent, stable compositions.
3. Water.

4. TFSA, having the properties recited above.
In additi.on to these components, the micellar solutions may contain, but are not required to contain, salts, hydrocarbons, or small amounts of other inorganic or organic material. Such constituents may be impurities, solvents, or by-products of syntheses used in forming the hydrotropic agent, or may be addi-tions found useful in forming the composition of this invention.
As an example of the latter, small amounts of inorganlc salts such as NaCl, Na2SO4, KNO3, CaC12, and the likel are sometimes helpful in promoting homogeneity with a minimum of amphipathic and hydrotropic agents. They may also yield compositions of lower freezing point, a property u=eful whell the composition is employed in cold climates. Similarly~, ethylene glycol, methanol, ethanol, acetic acld, or similar organic compounds may be incorporated into the compositions to improv= physical properties such as freezing point, viscosity, and density, or to improve stability.
~ ~ A~ stated above, the micelle-forming amphipathic agents which may be used in preparing the a~ueous solutions herein con-templated may be either cation-active, anion-active, or of the nonelectrolvtic type. Amphipathic agents generally have present at least one xadical containing about 1~ or more carbon atoms and not more than about 64 carbon atoms per molecule. This is true of the amphipathic agents employed in the present invention as a component of the vehicle or solvent or dispersant employed in the present compositions. The hydrophobic portions of these agents may be aliphatic, alicyclic, alkylalicyclic, aromatic, arylalkyl, or alkylaromatic. The preferred type of agents are those in which the molecule contains a long, uninterrupted carbon chain contain-ing from 10 to 22 carbon atoms in length. Examples of suitabls anion-active amphipathic agents include the common soaps, as well as materials such as sodium cetyl sulfate, ammonium lauryl sul-fonate, ammonium di-Lsopropyl naphthalene sulfonate, sodium oleyl glyceryl sulfate, mahogany and green sulfonates from petroleum or petroleum fractions or extracts, sodium stearamidoethyl sulfonate, dodecylbenzene sulfonate, dioctyl sodium sulfo-succinate, sodium naphthenate, and the like. Other suitable sulfonates are dis-closed and taught in U.S. Patent No. 2,278,171, issued February 17, 1942, to De Groote and Keiser.
Suitable cation-active compounds include cetyl pyridinium chloride, stearamidoethyl pyridinium chloride, trimethyl-heptadecyl ammonium chloride, dimethyl-pentadecyl sul~onium bromide, octade-cylamine acetate, and 2-heptadecyl-3-diethylene diaminoimidazoline diacetate.
Suitable nonelectrolytic amphipathic agents include the oleic acid ester of nonaethylene glycol, the steric acid ester of polyglycerol, oxyethylated alkylphenols, and long chain alcohol ethers of polyethylene glyools.
It is of course, well known that amphipathic compounds are readily and commercially available, or can be readily prepared to exhibit the characteristics of more than one of the above mentioned types. Such compoun~s are disclosed in U.S. Patent No. 2,262,743, dated November 11, 1941, to De Groote, Keiser and Blair. For convenience, in such instances where a surface-active material may show the characteristics of more than one of the above described types, it is understood that it may be classified under either or both types.
The mutual solvent or hydrotropic agents of the solution utilized in the present invention are characterizable as compounds 8S~
of a hydrophobic hydrocarbon residue of comparatively low molecular weight combined with a hydrophilic group of low molecular weight and are free from surface-active properties. The hydrophobic residue may contain from 2 to 12 carbon atoms and may be alkyl, alicyclic, aromatic, or alkyl substituted alicyclic or aromatic, or may be the hydrocarbon portion of a heterocyclic or hydrocarbon substituted heterocyclic group. The hydrocarbon residue may have branched or normal chain structure, but no branch may have a length of more than 7 carbon atoms from the point of attachment to the hydrophilic residue, counting a benzene or cyclohexyl group as beLng equivalent in length to an aliphatic chain of three carbon atoms. Where the hydrocarbon residue consists of not more than 4 carbon atoms, structures of the normal primary alkyl type are pre-ferred. Where the residue is made up of more than four carbon atoms, then structures of secondary and tertiary types are also good where the second and third branches may be methyl ox ethyl groups.
This hydrophobic hydrocarbon residue is combined either directly or indirectly with a hydrophilic group of one of the following groups:
(a~ A hydroxyl group which may be alcoholic, phenolic, or carboxylic;
(b) An aldehyde group;
(c) A carboxy amide group;
(d) An amine salt groupt (e) An amine group; and (f) An alkali phenolate group.
By "indirectedly combined with one of these groups" is meant that the hydrocarbon residue is combined as by etherification, esterification, or amidification, or the like, with another organic residue which contains not more than four carbon atoms and also ~i2~35~
one or more of the hydrophilic groups named above, provided that after said combination, at least one of the hydrophile groups remains free. Specific examples illustrating this class of compounds are: Ethyl alcohol, n-amyl alcohol, alphaterpineol, p-cresol, cyclohexanol, n-butyraldehyde, benzaldehyde, n-butyric acid, glycol mono-butyrate, propyl lactate, mono n-butyl amine hydrochloride, n-propionamid, ethylene glycol mono n-butyl amine hydrochloride, n-propionamid, ethylene glycol mono n-butyl ether, pyridine, methylated pyridine, piperidine, or methylated piperidines.
The solubilizer (mutual solvent or hydrotropic compound above described) is essentially a semi-polar liquid in the sense that any liquid whose polar character is no greater than that of ethyl alcohol a~d which shows at least some tendency to dissolve in wa~er, or have water dissolved in itj is properly designated as semi-polar.
The solubilizer or semi-po~ar li~uid indicated may be illustrated by the formula X - Z, in which X is a radical having 2 to 12 carbon atoms, and which may be alkylt alicyclic, aromaticl alkylalicyclic, alkylaryl, arylalkyl, or alicyclicalkyl in nature, and may, furthermore, include heterocyclic compounds and substituted heterocyclic compounds. ~here i5 the added limitation that the longest carbon atom chain must be less than eight carbon atoms, and that, in such characterization, cyclic carbon atoms must be counted as one-half. Z represents:
/ U / H / U
- OH; - N ; -C ; - CN ; - COOH; or - OMe \V O \V
where U and V are hydrogen or a hydrocarbon substituent and Me is an alkalie metal;
N
0 if X is a cyclic teritary amine nucleus;

~z~s~ -\
NH

if X is a cyclic secondary amine nucleus.
The semi-polar liquid also may be indicated by the following formula: - X - Y - R - (Z)n Here X and Z have their previous significance, R is ~ CH2 - , - C2H4 - , - C3H5 - ;
- C3H6- -or - C~H4 - O - C2H4 -and n is either one or two as the choice of R demands. Y is - one of the following:
O H H O O O
- ~ -N -; -N ~ C -O ; - O ~ O ; -S -.
In general, these hydrotropic agents are liquids having di-electric constant values between about 6 and about 26, and have at least one polar group containing one or more atoms of oxygen, and/or nitrogen. It is signifioant, perhaps, that all of the solubL1izers are of types known to be~able to form hydrogen bonds.
The choice of solubilizer or common solvent and its pro-:
portion in the~mixture depends somewhat upon the am~hipathic agent :
used~, he amount and kind of TFSA used, and the proportion ofwater used, and is best determined~by~preparing experimental mixtures on a; small scale. ~ ~
In some casés, it is desirable to include in the solution small amounts of acid, alkali, or inorganic salts, as it has been found that the presence of these electrolytes often gives so7utions having greater stability and a wider range of miscibility with water and organic material. Excess acid, when used, will usually be in solutions containing a cation-active or nonelectrolytic wetting agent, but not exclusively so. Excess alkali, when used, will usually be in a solution containing anion-active wetting agents, but, again, not exclusively.

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The acylated polyether polyol or TFSA utilized in this inven~ion is generally an organic polymer or semi-polymer with an average molecular weight above about 800 and below about 30,000 and has a structure which will allow orientation on polar surfaces with much or most of the elements of the molecule in a thin plane.
To be effectively adsorbed at oil-water or oil-rock interfaces and subsequently to be desorbed at water~rock interfaces, the TFSA must generally contain constituents which give it a highly distributed hydrophile and hydrophobe character, and without such concentrations of either hydrophilic or hydrophobic groups as to produce water solubility or oil solubility, in the ordinary macro-scopic sense. The TFSA also appears to differ from formerly used surfactants in that the effects on oil~water interfacial tensions as a function of concentration are limited~ While spreading efficiently at such interfaces to form thin films with spreading pressures up to about 35 to 40 dynes per cm, addition or larger amounts of TFSA have relatively little effect on interfacial tension. Also, the present TFSA constituent o the micellar solution in contrast to formerly used surfactants, has relatively little or no tendency to stabilize either oil-in-water or water-in-oil emulsions when present in normal use~amountsO
Usually the TFSA constituents applicable to the practice of the invention are organic molPcules containing carbon, hydrogen and oxygen, although in some instances they may also contain sulfur, nitrogen, silicon, chlorine, phosphorous or other elements.
Small amounts of inorganic material such as alkalies, acids or salts may appear in the compositions as neutralizing agents~
catalyst residues or otherwise. The critical requirements for the TFSA compositions are not so much compositional as structural and physical. They must be made up of hydrophilic (polar) moieties, usually ones capable of forming hydrogen bonds, such as hydroxyl, 3Si4 carbonyl, ester, ether, sulfonium, amino, ammonium, phospho or similar hydrogen bonding groups, connected by or to hydrophobic groups, such as alkylene, alkyl, cycloalkyl, aryl, arylene, aralkyl, polyalkylene, polyalkylyne, combinations of such groups and such groups containing relatively non-polar substituents, such as hydrocarbon, chlorine, fluorine and the like. Sometimes the hydrophobic moieties are larger and contain more atoms than the polar groups in the molecule, having a minimum of two carbon atoms in each group and up to as many as 36 carbon atoms, although the actual ratio of si~es depends greatly on the structure of the hydrophilic moiety. Most commonly, the hydrophobi~ groups will contain 14 to 22 carhon atoms and will have linear or sheet-like conformations allowi~g for relatively flat orientation on surfaces.
Polar moieties other than hydrogen bonding ones are not excluded from these compositions and, indeed, may be deliberately included in some structures to improve adsorption and interacial spreading tendencies. For example, quaternary ammonium groups, while incapable of forming hydrogen bonds, c~an improve spreading and interfacial adsorption in some applications by way of their highly ionized form which imparts cationic character to the mole-cules in which they occur and, via coulombic repulsion effects, can improve spreading in a film.
Generally, the TFSA constituents will contain at least two each of the required hydrophilic (polar) and hydrophobic moieties per molecule and commonly will contain many more of each.
The effective products, however, must have the three properties described above.
While, as pointed out above, the effective TFSA may be derived from a wide variety of chemical reactants and may contain numerous different groups or moieties, I have found that parti-cularly effective products are those which are described as an acylated polyether polyol having the formula:

/ [O(A)jH]n : R
~ R [(A)kH]J m : wherein:

; A i~s an alkylene oxide group, -CiH2iO-;

O~is oxygen;

:is a positive integer no greater than about 10;

j is a positive integer no greater than about 100;

: k is a positive integer no greater than about 100;

:~ 10 N is nitrogen;
-l is one of hydrogen, a monovalent hydrocarbon group containing ess~than;about C~ or ~ H]; :

L iS a pos~itive integer~no greater than about:100;

: R is~a hydrocarbon moiety of a polyol,~a primarv or secondary ~ amine~,~a primary or secondary:polyamine, a primary or ~ :
:: : . :
: : ; secondary~amino alcohol, or hydrogen; and :; :~ :
:m~+~:n is no greater:than about 4 when R is other than hydrogen and one of m:and n is zero and the other is uni~y when R

~ is hydrogen, :; : ~ :
:~ 20 said~acylated polyether polyol~being the reaction product of said polyether polyol and~a member selected ~rom the~alass consLsting~
of mono- and polybasic carboxylic acids, acid anhydrides, and iso-, diiso-, and polyisocyanates, said:acylated polyether polyol at about 25C (a) being less than about 1% by volume soluble~in water and in isooctane; (b) having a solubility paramet~r in the range of between about 6.9 and about 8.5; and (c) spreading at the interface between distilled water and refined mineral oil to form a film having a thickness no greater than about 20 Angstroms at a film pressure of about 16 dynes per cm.
Alternatively, the TFSA constituents may be described as acylated polyether polyols derivable by the reaction of an alkylene ~ LS;28S~ ' oxide containing less than about 10 carbon atoms with a member of the group consisting of polyols, amines, polyamines and amino alcohols containing from between about 2 to about 10 active hydrogen groups capable of reaction with alkylene oxides and the acylating agent being a member selected from the class consisting of mono- and polybasic carboxylic acids, acid anhydrides and iso-, diiso- and polyisocyanates.
Compositions incorporated within the scope of the formula set forth above contain an average of about 1~ or more hydroxyl groups per molecule and are generally composed of a cogeneric mixture of products obtained by condensing alkylene oxides with smaller molecules containing two or more reactive hydrogens as part of hydroxyl or amino ~roups.
Representative of these compositions is polypropylene - glycol, having an average molecular w~eight of about 1,200, to which about 20% by weight of ethylene oxide has been added. Such a polyether glycol is theoretically obtainable by condensing about 20 moles of propylene oxide with about one mole of water, followed by addLtion of about six moLes of e~hylene oxide. Alternatively, one may condense about 20 moles of propylene oxide with a pre-viously prepared polyethylene glycol of about 240 average molecular weight.
Alkylene ox-des suitable for use in preparing the TFSA
con~tituents used in the present solutions include ethylene oxide, propylene oxide, butylene oxide, 2-3-epoxy-2-methyl butane, tri-methylene oxide, tetrahydrofuran, glycidol, and similar oxides containing less than about 10 carbon atoms. Because of their reactivity and relatively low cost, the preferred alkylene oxides for preparing effective TFSA constituents are the 1,2-alkylene oxides (oxiranes) exemplified by ethylene oxide, propylene oxide and butylene oxide. In the preparation of many TFSA constituents, 85~ -more than one alkylene oxide may be employed either as mixtures of oxides or sequentially to form block additions of individual alkylene oxide groups.
Other suitable dihydric alcohols may be obtained by con-densing alkylene oxides or mixtures of oxides or in successive steps (blocks) with difunctional (with respect to oxide addition) compounds, such as ethylene glycol, methyl amine, propylene glycol, hexamethylene glycol, ethyl ethanolamine, analine, resorcinol, hydroquinone and the like.
Trihydric ether alcohois may be prapared by condensation of ethylene, propylene or butylene oxides with, for example, glycerin, ammonia, triethanolamine, diethanolamine, ethyl ethylene diamine or similar smaller molecules containing three hydrogens capable of reacting with alkylene oxides. Similarly, polvether alcohols with a multiplicity of hydroxyl groups may be obtained by condensing alkylene oxides with mu:Ltireactive starting compounds, such as pentaerythritol,~ glycerol, N-monobutyl ethylene diamine, txishydroxymethylaminomethane, ethylene diamine, diethylenetri-amine, diglyoerol, hexamethylene diamine, decylamine and cyclo-hexylamine. DeGroote, in U.S. Patent No. 2,679,511, describes a number of amino deriyed polyols which he subsequently esterfies.
Product 15-200, manufactured and sold by the Dow Chemical Company, and derived by oxyalkylation of glycerol with a mixture of ethylene and propylene oxides, is an example of a commercially available polyol of the kind contemplated herein.
Generally, these compositions will have average molecular weights of 15,000 or less and will be derived from reactive hydrogen compounds having 18 or fewer carbon atoms and 10 or fewer reactive hydrogens.
Other general descriptions of suitable compounds coming within the scope of the structure detailed above, along with ~ 5285~ ' methods for carrying out the actual manufacturing steps, are disclosed in "High Polymers, Vol. XIII, Polyethers," edited by N.G. Gaylord, John Wiley & Sons, New York, 1963.
Effective TFSA with improved performance may be prepared by acylation of the polyether polyol described above with a mono-or polybasic carboxylic acid, acid anhydride, isocyanate, diiso-cyanate or other polyisocyanate. An especially useful TFSA may be made by reacting an approximately difunctional polyether polyol with a difunctional carboxylylic acid, acid anhydride or iso-cyanate to form a polymeric ester or urethane. However, poly-merization is not always required, and where effected is usually not carried to the point of including a very large number of monomer units in the molecule. Frequently, effective reagents are obtained where residual, unreacted hydroxyl or carboxyl groups remain in the product or, where a polyisocyanate is used, one or more residual isocyanate groups or am:ino or substituted urea groups which result from reaction of residua:L end groups with water, followed by decarboxylation, may remain.
Examples of acylating agents suitabIe for preparing useful 20~ esters include acetLc acid, acetic anhydride, butyric acid, benzoic acid, abietic acid, adipic acld, diglycollic acid, phthallic anhydride, fumaric acid, hydroxyacetic acid, itaconic acid, succinic acid, dimerized fatty acids and the like. I have found the most generally useful acylating agents to be the di-and mono-basic acids and anhydrides containing less than 13 carbon atoms.
Examples of isocyanates useful for the acylation of a polyether polyol to produce an effective TFSA include methyliso-cyanate, phenyl isocyanate, cyclohexylmethylene isocyanate, and the like. Especially useful reactants are polyisocyanates containing to or more isocyanate groups and including phenylene diisocyanate, toluene diisocyanate, diphenylmethanediisocy~ate, hexa-methylene diisocyanate, 1,5-Naphthalene diisocyanate and poly-methylene polyphenyl isocyanates.
Following acylation reacti.ons of polyether polyols with polyisocyanates, where a stoichiometric excess of the latter re-actant is employed, remaining isocyanate groups may be left as such or may, by appropriate addition of water or monohydric alcohol, be converted to carbamic acid groups, which immediately undergo decarboxylation to yield residual amino groups, or carbamate groups.
Examples of acylated pol:yether polyols and their manufac-turing procedures are well known to the art, as disclosed in U.S. Patent No. 2,454,808, issued November 30, 1948, to Kirkpatrick, U.S. Patent No. 2,562,878, issued August 7, 1951, to Blair, U.S. Patent No. 2~679~511J issued May 25, 1954, to DeGroote, U.S. Patent No. 2,60.2,061~ issued July 1, 1~52~, also to DeGroote, "chemical Process Industries~l~by R.N. Shreve, McGraw Hill Publishiny Co., 1967, page;654 et seq., and "Hlgh :: : :
Polymers", Vol. XIII, edited by N.G. Gaylord, John Wiley & Sons, :: 20 1963, page 317 et seq.

As to the limits of:the various constituents of the micel-lar solutions containing TFSA, the following will serve as a guide, the percentages being by weight:

Percent TFSA Constituentsabout 5 to about 75 Hydrotropic Agentabout 2 to about 30 Amphipathic Agentabout 2 to about 30 Water about 15 to about 90 Although the exact function of the electrolytes previously referred to is not completely understood, the effect, in part, ~z~s~ .

may be due to the ability to bind water, i.e., to become hydrated.
This sugges~s that certain other materials which are highly hydro-phile in character and cleaxly differentiated from the classes of non-polar solvents and semi-polar solubilizers may be the functional equivalent of an electrolyte. Substances of this class which ordinarily do not dissociate include glycerol, ethylene glycol, diglycerol, sugar, glucose, sorbitol, mannitol, and the like.
Also, as stated above, these solutions may contain other organic constituents such as hydrocarbons~ These frequently are used as thinning agents, azetropic distillation aids or reflux temperature controllers in the manufac~ure of the TFSA constituent and may be left therein when the present micellar solutions are prepared. To the extent that such compounds are present they appear to compete somewhat with the TFSA constituent for micelle space, thus limiting, to some extent, the maximum amount of TFSA
constituent which can be brought into homogeneous solution.
Selection of an ef~ective TFSA composition for a given petroleum emulsion and determination of the amount required is usually made by so-called "bottle tests", conducted, in a typical ~0 situation, as follows:
A sample of fresh emulsion is obtained and lO0 ml portions are poured into each of several 180 ml screw top prescription or similar graduated bottles. Dilute solutions (1~ or 2%) of various TFSA constituents are prepared in isopropyl alcohol. By means of a graduated pipette, a small volume of a TFSA solution is added to a bottle. A similar volume of each composition is added to other bottles containing emulsion. The bottles are then closed and transferred to a water bath held at the same temperature as that employed in the field treating plant. After reaching this temperature, the bottles are shaken briskly for several minutes.

8~4 After the shaking period, the bottles are placed upright in the water hath and allowed to stand quietlyO Periodically, the volume of the separated water layer is recorded along with observations on the sharpness of the oil-water interface, appearance of the oil and clarity of the water phase.
After ~he standing period, which may range from 30 minutes to several hours, depending upon the temperature, the viscosity of the emulsion and the amount of TFSA compositions used/ small samples of the oil are removed by pipette or syringe and centri-fuged to determine the amount of free and emulsified water leftin the oil. The pipette or syringe used to remove the test samples should be fitted through a stopper or other device which acts as a position guide to insure that all bottles are sampled at the same fluid level.
The combinod information on residuaI water and emulsion, speed of the water separation and interface appearance provides the basis for selection of the generally most effective TFS~
: constituent, Where no~e of the results are satisfactory, the tests should be repeated using higher concentrations of:TFSA
constLtuents and, conversely, where all results are good and similar, the tests should be repeated at lower concentrations until good discrimination is possible.
In practicing the process for resolving petroleum emul-sions of the water-in-oil type with the present micellar solution, such solution is brought into contact with or caused to act upon the emulsion to be treated, in any of the various methods or apparatus now generally used to resolve or blreak petroleum emulsions with a chemical reagent, the above procedure being used alone or in combination with other demulsifying procedure, such as the electrical dehydration process.
One type of procedure is to accumulate a volume of emulsified oil in a tank and conduct a batch treatment type of demulsification procedure to recover clean oil. In this procedure, the emulsion is admixed with the micellar TFSA solution, for example, by agitating the tank of emulsion and slowly dripping the micellar TFSA solution into the emulsion. In some cases, mixing is achieved by heating the emulsion while dripping in the micellar TFSA solution, depending upon the convection currents in the emulsion ~o produce satisfactory admixture. In a third modification of this type of treatment, a circulating pump withdraws emulsion from, e.g., the bottom of the tank and reintroduces it into the top of the tank, the micellar TFSA solution being added, for example, at the suction side of said circulating pump.
In a second type of treating procedure, the micellar TFSA
solution is introduced into the well fluids at the wellhead, or at some point between the wellhead and the final oil storage tank, by means of an adjustable proportioning mechanism or proportioning pump. Ordinarily, the flow of fluids through the subsequent lines : and fittings suEfices to produce the desired degree of mixing of mlcellar TFSA solution and emulsion, although, in some instances, additional mixing devices may be introduced into the flow system.
: 20 In this general procedure, the system may inolude various mechanical devices for withdrawing free water, separating entrined water, or accomplishing quiescent settling of the chemically tr~ated emulsionO
Heating devices may likewise be incorporated in any of the treating procedures described~herein.
A third type of application (down-the-hole) of micellar -TFSA solution to emulsion is to introduce the micellar solution either periodically or continuously in diluted form into the well and to allow it to come to the surface with the well fluids, and then to flow the chemical-containing emulsion through any desirable surface equipment, such as employed in the other treating procedures.
This particular type of application is especially u~eful when the 8S4~

micellar solution is used in connection with acidification of calcareous oil-bearing strata, especially if dissolved in the acid employed for acidification.
In all cases, it will be apparent from the foregoing description, the broad process consists simpl~ in introducing a relatively small proportion of micellar TFSA solution into a relatively large proportion of emulsion, admixing the chemical and emulsion either through natural flow, or through special apparatus, with or without the application of heat, and allowing the mixture to stand quiescent until the undesirable water content of the emulsion separates and settles from the mass.
Besides thelr util1ty for breaking petroleum emulsions, ~the present micellar TFSA solutions, as mentioned ea~lier, may be ;~ used to prevent emulsion formation in steam flooding, in secondary waterflooding, in acidizing of oil-producing formationsj and the ike.
Petroleum oils, even after demulsification, may contain substantial amounts of inorganic salt~, ei~her in so1id form or as sma11~rema1ning brine droplets. For this reason, most petroleum ; 20 oils~are desa1ted~prior to refining. The desalting step~is effected by adding a~d mi~xing with~the oil a ~ew volume percentages of fresh water to co~tact the brine and salt~ In the absence of demulsifier,~such added water would also become emulsified with-out effecting its washing action. The present micellar solutions may be added to the fresh water to prevent its emulsification and to aid in phase separation and removal of salt by the desalting process~ Alternatively, if desired, they may be added to the oil phase as are present aromatic solvent compositions.
Most petroleum oil, along with its accompanying brines and gases, is corrosive to steel and other metallic structures with which it comes in contact. Well tubing, casing, flow lines, separators and lease tanks are often seriously attacked by well fluids, especially where acidic gases such as H2S or CO2 are produced with the liquids, but also in systems free of such gases.
It has been known for some time, and as exemplified in U.S. Patent 2,466,517, issued April 5, 1949, to Chas. M. Blair and Wm. F. Gross, that such corrosive attack of crude oil fluids can be mitigated or prevented by addition to the fluids of small amounts of organic inhibitors. ~ffective inhibitors compositions for this use are usually semi-polar, surface active compounds containing a nonpolar hydrocarbon moiety attached to one or more polar groups containing nitrogen, oxygen or sulfur or combinations of such elements. Generally these inhibitors or their salts are soluble in oil and/or water (brine) and frequently appear to be able to form micelles in one or both of these phases. Typical inhibitors include amines such as octyl amine, dodecyl amine, dioctodecyl amine, butyl naphthyl amine, dicyclohexyl amine, benzyl dimethyldodecyl ammonium chloride, hexadecylaminopropyl amine, decyloxypropyl amine, mixed amines prepared by hydrogenation of nitrile derivatives of tall oil fatty acids, soya acid esters of~monoethanol amine, 2-undecyl, l~amino ethyl imidazoline and a wlde variety of caticnic nltrogen compounds of semi-polar character.
Also effective in some applications are nonyl succinic acld, dio-cylnaphthalene suIfonic acid, trimeric and dimeric fatty acids, propargyl alcohol, mercaptobenzothiozole, 2, 4, 6-trimethyl-1, 3,

5-trithiaane, hexadecyldimethyl benzimidazolium bromide, 2-thio-butyl-N-tetrodecylpyridinium chloride, tetrahydronaphthylthio-morpholine, and the like.
In contrast to the TFSA, corrosion inhibitors appear to function by forming on the metal surface strongly adherent, thick, closely packed films which prevent or lessen con~act of corrosive fluids and gases with the metal and interfere with ionic and electron transfer reactions involved in the corrosion process.
Corrosion inhibitors are quike commonly introduced down the casing annulus of oil wells where they commingle with the well fluids before their travel up the well tubing and thus can effec-tively prevent corrosion of well equipment. Where corrosive at~ack occurs at the surface, the inhibitor may be introduced at or near the well head, allowing it to adsorb on the flow lines and surface equipment to insure protection.
Addition of inhibitor at either downhole or surface locations may be combined conveniently with demulsifier addition since the latter is also frequently introduced in one of these locations.
Inhibitors such as those mentioned above, may generally be incorporated into the TFSA micellar solutions, replacing a portion of or in addition to the TFSA constituent. Also, since many of these inhibitors are themselves micelle-forming amphipathic agents, they may be included in the micellar solution as such, replacing other amphlpathic agents whi¢h might be otherwise utilized. Combining the micellar solution with corrosion inhibitor permits more economic chemical treatment by reducing inventory to one compoundj requiring only one chemical injection system rather than two and lessening the labor and supervision required.
Still another important effec~ of using the micellar solution of TFSA and corrosion inhibitor results from the prevention of emulsification by the inhibitorO Frequently, it has been found that inhibitor in the amount required for effective protection causes the formation of very refractive emulsions of water and hydrocarbon, especially in systems containing light, normally nonemulsifving hydrocarbons such as distillate, casing head gasoline, kerosene, diesel fuel and various refinery fractions.

ii4 Inhibitors are commonly used in refinery systems where emulsifi-cation is highly objectionable and where the compositions could be designed to include an effective emulsion preventative micellar solution of TFSA.
Inhibitor use may range ~rom a few to several hundred parts per million based on the oil to be treated, depending upon the severity of corrosion. For a given oil field or group of wells, tests will normally be run to determine the requirement for micellar solution of TFSA and for inhibitor and a composition incorporating these components in approximately the desired ratio will be pre-pared. In some instances, the requirement for micellar solution of TFSA in the best concentration may result in use ~f corrosion inhibitor, employed as micelle-former, in some excess over that required for inhibition. This will not affect the utility of the micellar solution and will provide a comfortable excess of inhibi-tion which can be helpful during the periods when higher corro-sivity may be encountered.
Examples of micellar solutions employing TFSA with mhibitor in water dispersible, micellar solutions are given below.
Selection of the proper corrosion inhibltor for a given system or oil is usually made by conducting laboratory tests under conditions simulating those encountered in the well or flowline. Such tests are exemplified by that described in Item No. lK155, "~roposed~Standardized Laboratory Procedure for Screening Corrosion Inhibitors for Oil and Gas Wells", published by the National Association of Corrosion Engineers, Houston, Texas.
EXAMPLES OF THIN FILM SPREADING AGENTS
EXAMP~E I
Reference is made to U.S. Patent No. 2,562,878, dated August 7, 1951, to Chas. M. Blair, Jr., which describes the preparation of demulsifiers which are polyesters of dicarboxylic acids and polyhydric alkylene ether glycols. Using the procedure described therein, 150 1bs. of diglycolic acid was reacted with'2,000 lbs.
of "Pluronic L-62" manufactured by Wyandotte Chemical Corporation of Wyandotte, Michigan. "Pluronic L-62"~is described as a poly-propylene glycol havlng a molecular weight of about 1,650 to which has been added and condensed therewith about 25% by weight of ethylene oxide.
The esterification reaction was continued until the acid number of the reaction mixture had dropped to about 15.
The resulting product' was a moderately viscous liquid, :
insoluble to the extent of 1% in either water or isooctane, had a Solubility Parameter of 8.1, and s~read at the interface between white mineral oll and water at 25C to yield a fllm pressure of 22 dynes per c~ at a calculated thickness of 14 Angstroms.

:
EXAMPLE 'II
' Using the procedure des'cribèd by C. H. M. Roberts in U.S.
Patent No. 1,977,146, dated October 23, 1934, one mole'each`of the mono- and diglycerides' of ricinoleic acid were'reacted with three moles of phthallic anhydride. ~he'reaction was stopped short of gelation to yield a viscous, reddish polymer, insoluble in water and isooctane, having a solubility parameter of 8.4 and spreading at the white oil-dis~illed water interface with a pressure of 20 dynes per cm at a calculated thickness of 10 Angstro~s.

EXAMPLE III
To l,000'parts of commercial polyoxypropylene'glycol of molecular weIght of about 2,000 was added 200 parts of ethylene * Trade Mark l oxide. Reaction was conducted as in Example I. After completion of the ethylene oxide addition, a mild vacuum was applied for 30 minutes to remove any unreacted oxide. The temperature was lowered to 40C and 5 parts of dodecylbenzene~'sulfonic 'acid were added to the reaction mass while'stirring. Eighty parts of phenyacetic acid were then introduced and heating and stirring were commenced under a take-'off condensor. The temperature'was slowly ra1sed to about 160C over a three-hour period and was held at this temperature ~for an additional 2 hours.
The'product was then cooled and drummed. It was an effec-tive'demulsifier espec'ially for pet'roleum emulsions encountered in southern Louis1ana, and met the'cr1teria recited previously for such interfacially active'compounds.
::
:`::: :: ::
FX~MPLE IV
Two and one-~hal parts of tris-hydroxymethylaminomethane were substituted for the dipropylene glyco1 in Example I of~my co-pendin~ application Serial No.' _ 6 , ~ , , fL1ed , entltled "Petroleum De~ulsifier's Comprising A
Polyether Polyol". ~ ,;

To the above~product was added with stirr1ng 5~parts of maleic anhydride. The temperature was then raised to 130C
while the vessel was open to a take-off condensor. St'irring and heating were continued unt1l a sample of the react1on mass had a viscosity in the range of 900 to l,lO0 centipoises at 80C.
This product was an effective thin film spreading agent and especially useful as a dem,ulsifier for petroleum emulsions occurring in western Kansas and in Kuwait.

.

~;2~35~

EX~MPLF V
Using the apparatus and procedure of Example I, 4,000 lbs. of polypropylene glycol of average molecular weight l,200 was condensed with 700 lbs. of ethylene oxide. Forty pounds of potassium hydroxide was dissolved in the polypropylene glycol prior to oxide addition, which was carried out within the tempera-ture range of about 140 - 160C. under a maximum pressure of about 75 psi.
After completion of the above reaction, the temperature was lowered to about 60C and the reaction vessel was connected to a take-off condensor. Fifty pounds of 85~ phosphoric acid was slowly added to the reaction mass with stirring~followed by 314 ; lbso of adipic acid. The temperature was then slowly brought to 145 - 155C. while continuing to stir and to distill water from the reaction mixture. The acid number of the produot was periodi-cally determined. When a valve between 10 and 15 mg. KOH per gm.
was reached, heating was stopped, the product was cooled to room temperature and filled into 55-gallon drums.
This product has a calculated equivalent weight in excess of 4,000, is insoluble to the extent of 1% in water and isooctane, ;; : :
has a solubility parameter of 7.9 and rapidly spreads at the inter-face between white oil and distilled water, at 25C, to give a film pressure of 18 dynes~per cm at a calculated thickness of 18 Angstroms.
EXAMP_E VI
Into a l,000 gal. stainless steel autoclave, equipped with steam jacket, internal cooling coils, stirrer, condensor and several inlet feed lines were place 92 lbs. of glycerol. 2,750 lbs.
of a mixture of 2,250 lbs. of propylene oxide and 500 lbs. of ethylene oxide was prepared in a separate weighed feed tank.

i;2~3~4 Twelve pounds of a 50% aqueous solution of potassium hydroxide was stirred into the glycerol while heating to about 120C.
During this period, the vessel was connected to a steam jet vacuum system through the condensor, arranged in take-off position.
Stirring under vacuum was continued until the evolution of water had effectively ceased.
The vessel was then closed and the mixed oxides were introduced slowly. The resulting exothermLc reaction was con-trolled by the oxide addition rate such as to allow a slow increase in temperature to about 150C. After the addition of :`
about 800 lbs. of oxides the rate of reaction declined. The oxide addition line was then closed, the temperature lowered to 110C, the vessel was vented briefly to the vacuum jet, and an additional 25 lbs. of 50% aqueous solution of potassium hydroxide was intro-duced into the reaction mass which was then stirred under vacuum at 120 - 140C until water evolution ceased.
The vessel was closed, the oxide inlet line was again opened and reaction was~continued with the fresh catalyst~ holding -~ ~ the temperature at about 150C under a maximum pressure of about ~:: ? ~ 50 psi until the whole of the ~,750 lbs. of mixed oxide had been reacted ~ After cooling this batch to about 120C, 1,860 lbs. of commercial mixed xylene was pumped into the autoclave and the whole was stirred and adjusted to a temperature o about 95C. A solu-tion of 125 lbs. of toluene diisocyanate in 200 lbs. o xylene was then slowly pumped into the vessel while maintaining the tempexa-ture at 100 ~ 5C~ for approximately the two hours required for the addition. The temperature was then raised to 140C and stirring was continued until the viscosity at 100C was within the range of 1,000 to 1,500 centipoises. Heating was then dis-continued and the batch was cooled quickly to allow transfer to storage.

85~

A sample of this product, after removal of xylene by vacuum distillation was found to meet the three criteria ~or a TFSA.
EXAMPLES OF MICELLAR SOLUTIONS OF TFSA's _ . . .......... .
EXAMPLE A
Wt. %
Product o Example II 40 2-heptadecyl-3-triethylene triaminoimidazoline 6 Acetic Acid 1.5 Phenol 2.5 ; 10 n-Butanol 10 Water 40 Besides having good demulsification action, this product :: :
is an effective corrosion in~ibitor for down-the-hole use, the imidazoline used as the amphipathic agent being a strongly ad~
sorbed inhibitor for steel ln anaerobic systems.
EXAMPLE B
Wt.
i ~ ~
Product of Example IV 20 n-DodeGylbenzene sulfonic acid 6 20 Methanol 14 Ethylene glycol monobutyl ether 10 Water 50 This clear,~homogeneous solution is quite acidic. It can be combined with 15~ hydrochloric acid used for acidizing calcareous oil-producing formations and acts therein to prevent emulsification of acid and &pent acid.
EXAMPLE C
Wt. %
Product of E~ample II 70 Oleyl amine 10 359~ .

Acetic Acid 3 n-Propanol 2 Water lS
This is a clear, homogeneous but viscous solution.
EXAMPLE D
Wt. %
Product of Example III 35 Dinonylphenolsulfonic acid 50% aqueous UaOH 2 10 : Isopropanol ~ 9~
Methanol 10 :
;~ Water ~ ~ 36 : EXAMPLE E
-: Wt. %
~ Product of Example I 28 : Ethyleneglycol monobutyl ether 14 5-mole ethylene adduct of p-nonyI phenol 14 : Water 44 This product may be diluted further with water to form ~20 clear to slightly opalescent solutions.
E XAMPLE F
Wt. %
Product of Example VI 41.0 Ammonium dodecylbenzene sul~onate 17.5 Isopropanol 24.0 Water 17.5 This product is an effective micellar composition for numerous petroleum emulsions, but is especially effective as a . component in ~Z85~1~
synergistic blends with the composition of Examble B and with other compositions such as those disclosed in my co-pending applications cited in detail, above.
The product of Example F has also been found to be an effec-tive waterflood additive, especially in combination with aqueous micellar solutions of resinous polyoxide adducts such as those , described in ~y co-pending Canadia-n application, Serial No. 361,787 filed October 8, 1980, and entitled, "Micellar Solu-tions Of Thin Film Spreading Agents Comprising Resinous Poly-alkylene Oxide Adducts".

EXAMPLE G
Wt.
Product of Example IV 35 :
Oc-taethyleneglycol Monooleate l0 Ethylene glycol ~monobutyl ether 12 :
"Polyox" coagulant grade (a commercial polyethylene oxide~ of about 5 million molecular~weight~ 2 Wàter 41 :
This~product is a very viscous, redish liquid, readily dis-~20 persible in water to~form s11ght1y opalescent solutions. It iseffective alone or in combination with other aqueous systems or diluted in water~as a flooding agent for oi] recovery, especial-ly where a higher viscosity agent is needed for mobility control.
Further, it is an effective demulsifier for heavy oil emul-sion produced in the McKittrick, Ca. field and is even more effective in a 50-50 blend with the compositon of Example E.
Still further, this product is found to assist in the floc-culation and sedimentation of finely ground hematite particles during the decantation of aqueous slurries of the ground ore to remove sand and clay minerals and effect benefic-iation of the iron-containing values.

s~ ~
Among procedures which have been found useful in selecting effective mîcellar TFSA solutions for this use, one involves a determination of oil displacement efficiency from prepared oil-containing rock cores in equipment described below. A tube of glass or transparent polymethacrylate ester, having an inside diameter of about 3.5 cm (1~ in.) and a length of about 45 cm (18 in.), is fitted with inlet connections and appropriate valves at each end. rrhe tube is mounted vertically on a rack in an air bath equipped with a fan, heater and thermostat which allows selection and maintenance of temperatures in the range of between about 25 - 130C.
To select an effective micellar TFSA solution for use in a given oil formation, samples of the oil, of the producing rock formation and of the water to be used in the-flooding operation were obtained. The formation rock is extracted wi~h toluene to remove oil, is dried and is then ground in a ball mill to the point where a large percentage passes a 40 mesh sieve. The fraction between 60 and 100 mesh in size is retained. The tube described above is removed from the air bath, opened and, after insertion of a glass wool retainer at the lower end, is packed with the ground formation rock. The tube is tapped gently from time-to-time during filling to ensure close packing and is visually inspected to assure absence of voids.
The tube is then returned to the air bath, connected to the inlet tubing, the temperature is adjusted to the oil formation temperature and water representative of that produced from the formation is admitted slowly through the bottom line from a cali-brated reservoir in an amount just sufficient to fill the packed rock plug in the tube. This volume is determined from the calibra-tions and is referred to as the "pore volume", being that volume ofwater just sufficient to fill the pores or interstices of the packed plug rock.

35i4 The upper line to the reservoir is then connected to a calibrated reservoir containing the oil representing that from the formation to be flooded. By proper manipulation of valves, the line is filled with oil which is then slowly pumped into the core from the reservoir after the lower valve is opened to allow dis-placement of the formation water.
As breakthrough of oil at the bottom is noted, pumping is stopped and the volume of oil introduced into the sand is deter-minea from the reservoir readings. This is referred to as the volume of oil in place. The tube;of sand containing oil is then left in the air bath at the temperature of the formation for a period of three days to allow establishment of equilibrium between the ground formation rock and the oil with respect to adsorption of oil constituents on the rock and lowering of interfacial tension.
The time allowed for equilib~ium may be varied widely. At higher temperatures, the time required to reach equilibrium is probably reduced. Usually, for comparative test~, three days are allowed to age the oiI-rock plug.~ Results wlth this procedure closely ~ simulate work with actual cores o~ oil-bearing rock.
The oil and water samples used for ~est purposes are pre-ferably taken under an inert gas such as high purity nitrogen, and are maintained out of contact with air duriny all miniuplations in order to prevent o~idation of the oil and concomitant introduction of spurious polar, surface-active constituents in the oil. At this point, the rock-oil system simulates the original oil forma-tion before primary production oil has commenced and well before any secondary waterflood operation.
The upper inlet line to the tube is now connected to the sample of water used in the flooding of the oil formation and, by means of a syringe pump or similar very small volume positive displacement pump, the water is pumped into the sand body from ~ i2~
the top to displace fluids out of the bottom tubiny connection into a calibrated receiver. The pumping rate is adjusted to one simulating the rate of flood water advance in an actual operation, which is usually in a range of 1 to 50 cm per day. Pumping is maintained at this rate until two pore volumes of water have been pumped through the sand.
The volumes of fluids collected in the receiver are measured and the relative amount of oil and water displaced from the rock sample are determined and recorded. Of special interest is the volume of oil displaced as a fraction of the original pore volume. This formation may be viewed as an indication of the approximate percentage of oil originally in place which is produced by natural water drive following drilling of a well into the rock ~formation followed by the primary phase of field production carried to the approximate economic limit.
Following this step, one to three additional pore volumes of water containing the TFSA micellar solution to be tested are pumped slowly through the plug and the volumes of additional oil and water displaced are;determined. Typically, where such an initial "slug" of mi~ellar :~FSA solution is introduced, it may be contained in a volume of fluid ranging from 1% to 100% of the pore volume, but most frequently it will be in a slug volume of 10~ to 50% of pore volume.
After this final displacemen step, the produced oil and water are again measured. By comparing the amount of oil produced by this additional injection of water containing, or preceded by a solution, of micellar TFSA solution with the amount produced when the same volume of water containing no TFSA solution is injected, one can evaluate the effectiveness of the particular micellar TFSA solution used for enhancing the recovery of additional oil over and above that obtained by ordinary waterflooding.

8~ -Generally, six ox more sand columns of the kind described above are mounted in the heated air bath. Test of a given micellar TFSA solution is then run in triplicate, using identical conditions and conc~ntrations, simu~taneously with three blank tests run similarly but without addition of micellar TFSA solution to the water.
The composition of Example D was tested by this procedure with the following conditions:

Oil -- Ranger Zone, Wilmington, Calif., field API Gravity approximately 13.5 Water -- Mixed water used in ~lood operations Airbath Temperature -- 150F (Same as formation temperature) Oil was displaced by pumping two pore volumes of water into the sand. After measuring the volumes of oil and water produced through the bottom line, a further 0.2 pore volumes of water con-tainlng 2,600 ppm o~ the composition of Example F was injected followed by 2.8 volumes of water containing 175 ppm of the composi-:
tion of Example D. Measurement of the volumes of oil and water produced were read after each 0.2 pore volumes of water was injected.
Results of this test at the points of 2,3 and 5 pore volumes of injected water are gi~en in the table below wherein averages of three duplicate determinations are presented.

Oil Recovery as ~ of Oil in Place . _ , ,, _ .
Composition of Ratio of Increment Example F of Oil Production Added to Water After Initial 2 Pore Volumes (P.V.)No Chemical after Initial P.V. Chemical/
of Water Injected Addition 2 P.V. o-f Water No Chemical _ . , , , _ . .
2 36.5 36.5 3 40.0 43.7 2.1 5 43.1 53.0 2.5 ~i;213S4 Use of the composition of Example F in the amounts given above resulted in the production of 110% more oil from injection of one incremental pore volume of water than was produced by water injection alone and gave 150% more oil after three incremental pore volumes of treated water injection.
Although the invention has been described in terms of specified embodiments which are set forth in detail, it should be understood that this is by illustration only and that the invention is not necessarily limited thereto, since alternative embodiments and operating techniques will become apparent to those skilled in the art in view of the disclosure. Accordingly, modifications are contemplated which can be made without departing from the spirit of the described invention.

: .

Claims (38)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A micellar thin film spreading agent composition, comprising:
(1) from between about 5% and about 75% by weight of an acylated polyether polyol having the formula:

wherein:
A is an alkylene oxide group, -CiH2iO-;
O is oxygen;
i is a positive integer no greater than about 10;
j is a positive integer no greater than about 100;
k is a positive integer no greater than about 100;
N is nitrogen;
R1 is one of hydrogen, a monovalent hydrocarbon group containing less than about C11, or [ALH];
L is a positive integer no greater than about 100;
R is a hydrocarbon moiety of a polyol, a primary or secondary amine, a primary or secondary polyamine, a primary or secondary amino alcohol, or hydrogen; and m + n is no greater than about 4 when R is other than hydrogen and one of m and n is zero and the other is unity when R
is hydrogen, said acylated polyether polyol being the reaction product of said polyether polyol and a member selected from the class consisting of mono- and polybasic carboxylic acids, acid anhydrides, and iso-, diiso-, and polyisocyanates, said acylated polyether polyol at about 25°C: (a) being less than about 1% by volume soluble in water and in isooctane; (b) having a solubility parameter in the range of between about 6.9 and about 8.5; and (c) spreading at the interface between distilled water and refined mineral oil to form a film having a thickness no greater than about 20 Angstroms at a film pressure of about 16 dynes per cm; (2) from between about 2% and about 30% by weight of a hydrotropic agent having one of the formulas:
(A) X - Z
wherein X is an alkyl, alicyclic, aromatic, alkylalicyclic, alkyl-aryl, arylalkyl, alicyclicalkyl, heterocyclic or substituted heterocyclic radical having 2 to 13 carbon atoms; and wherein Z is one of: -OH; ; -CHO; ; -COOH; and -OCH3;
where U and V are hydrogen or hydrocarbon substituents;
(B) -X-Y-R-(Z)n, wherein:
Z is one of -OH; ; -CHO; ; -COOH; and -OCH3;
X is an alkyl, alicyclic, aromatic, alkylalicyclic, alkylaryl, arylalkyl, alicyclicalkyl, heterocyclic or substituted heterocyclic radical having 2 to 12 carbon atoms;
R is a member selected from the class consisting of, -CH2-, -C2H4-, C3H5=, -C3H6, and -C2H4-O-C2H4-;
n is either a one or two integer, the integer dependent upon the selection of R;
Y is a member selected from the class consisting of:

, , , , -O-, and -S-;
and U and V are hydrogen or hydrocarbon substituents;
(3) from between about 2% and about 30% by weight of an amphipathic agent having at least one radical having from between about 10 and about 64 carbon atoms per molecule; and (4) from between about 15% and about 90% by weight, water.

2. The composition of Claim 1 wherein said acylated poly-ether polyol is the reaction product of a difunctional polyether polyol and a difunctional member of the class consisting of car-boxylic acids, acid anhydrides and isocyanates.

3. The compositon of Claim 1 wherein said acylated poly-ether polyol is the reaction product of a polyether polyol and an acylating agent selected from the class consisting of di- and mono-basic acids and anhydrides having C13 or less.

4. The composition of Claim 1 wherein said acylated poly-ether polyol is the reaction product of a polyether polyol and a polyisocyanate containing at least two isocyanate groups.

5. A micellar thin film spreading agent composition, com-prising: (1) from between about 5% and about 75% by weight of an acylated polyether polyol wherein said polyether polyol is de-rived from the reaction of an alkylene oxide containing less than about 10 carbon atoms with a member of the group consisting of polyols, amines, polyamines and amino alcohols containing from about 2 to about 10 active hydrogen groups capable of reaction with alkylene oxides, and the acylating agent being a member se-lected from the class consisting of mono- and polybasic carboxylic acids, acid anhydrides and iso-, diiso-, and polyisocyanates, said acylated polyether polyol, at about 25°C: (A) having a solu-bility in water and isooctane at about 25°C of less than about 1%, by volume; (B) having a solubility parameter from between about 6.8 and about 8.5; and (C) spreading at the interface between white, refined mineral oil and distilled water to form a film having a calculated thickness no greater than about 20 Ang-stroms, at a spreading pressure of about 16 dynes per cm;
(2) from between about 2% and about 30% by weight of a hydro-tropic agent comprising a semi-polar hydrogen bond forming compound containing at least one of oxygen, nitrogen and sulfur and from between about 2 and about 12 carbon atoms;
(3) from between about 2% and about 20% by weight of an amphi-pathic agent having at least one radical having from between about 10 and about 64 carbon atoms per molecule; and (4) from between about 15% and about 90% by weight, water.

6. The composition of Claim 1 or 5 wherein the hydrotropic agent is an alcohol.

7. The composition of Claim 1 or 5 wherein the hydrotropic agent is an hydroxy ester of a polyol.

8. The composition of Claim 1 or 5 wherein the hydrotropic agent is an aldehyde

9. The composition of Claim 1 or 5 wherein the hydrotropic agent is a semi-polar oxygen-containing compound capable of form-ing hydrogen bonds.

10. The composition of Claim 1 or 5 wherein the hydrotropic agent is an amine.

11. The composition of Claim 1 or 5 wherein the hydrotropic agent is a carboxy amide.

12. The composition of Claim 1 or 5 wherein the hydrotropic agent is a phenolate.

13. The composition of Claim 1 or 5 wherein the amphipathic agent is a hydrophobic hydrocarbon residue-containing composition wherein the hydrocarbon residue is aliphatic, alkylalicyclic, aromatic, arylalkyl or alkylaromatic.

14. The composition of Claim 1 or 5 wherein the amphipathic agent contains an uninterrupted chain of from between about 10 and about 22 carbons.

15. The composition of Claim 1 or 5 whrein the amphipathic agent is an anion-active soap.

16. The composition of Claim 1 or 5 wherein the amphipathic agent comprises sodium cetyl sulfate.

17. The composition of Claim 1 or 5 wherein the amphipathic agent comprises ammonium lauryl sulfonate.

18. The composition of Claim 1 or 5 wherein the amphipathic agent comprises ammonium di-isopropyl naphthalene sulfonate.

19. The composition of Claim 1 or 5 wherein the amphipathic agent comprises sodium oleyl glyceryl sulfate.

20. The composition of Claim 1 or 5 wherein the amphipathic agent comprises mahogany or green sulfonates of petroleum, petro-leum fractions, or petroleum extracts.

21. The composition of Claim 1 or 5 wherein the amphipathic agent comprises sodium stearamidoethyl sulfonate.

22. The composition of Claim 1 or 5 wherein the amphipathic agent comprises dodecylbenzene sulfonate.

23. The composition of Claim 1 or 5 wherein the amphipathic agent comprises dioctyl sodium sulfo-succinate.

24. The composition of Claim 1 or 5 wherein the amphipathic agent comprises sodium naphthenate.

25. The composition of Claim 1 or 5 wherein the amphipathic agent comprises cetyl pyridinium chloride.

26. The composition of Claim 1 or 5 wherein the amphipathic agent comprises stearamidoethyl pyridium chloride.

27. The composition of Claim 1 or 5 wherein the amphipathic agent comprises trimethyl-heptadecyl ammonium chloride.

28. The composition of Claim 1 or 5, wherein the amphipathic agent comprises dimethyl-pentadecyl sulfonium bromide.

29. The composition of Claim 1 or 5 wherein the amphipathic agent comprises octadecylamine acetate.

30. The composition of Claim 1 or 5 wherein the amphipathic agent comprises 2-heptadecyl-3-diethylene diamino-imidazoline diacetate.

31. The composition of Claim 1 or 5 wherein the amphipathic agent comprises the oleic acid ester of nonaethylene glycol.

32. The composition of Claim 1 or 5 wherein the amphipathic agent comprises the stearic acid ester of polyglycerol.

33. The composition of Claim 1 or 5 wherein the amphipathic agent comprises an oxyethylated alkylphenol.

34. The composition of Claim 1 or 5 wherein the amphipathic agent comprises an alcohol ether of a polyethylene glycol,

35. The composition of Claim 1 or 5 wherein the amphipathic agent is anionic.

36. The composition of Claim 1 or 5 wherein the amphipathic agent is cationic.

37. The composition of Claim 1 or 5 wherein the amphipathic agent is nonionic.

38. The composition of Claim 5 wherein the solubility parameter at about 25°C of the acylated polyether polyol is from between about 7.1 and about 7.9.