US2078654A - Process for breaking petroleum emulsions - Google Patents

Description

Fatented Apr. 27, 1937 UNITED STATES PATENT OFFICE PROCESS on BREAKING PETROLEUM EMULSIONS N0 Drawing. Application June 8, 1936, Serial No. 84,179

8 Claims.

This invention relates to the treatment of emulsions of mineral oil and water, such as petroleum emulsions, for the purpose of separating the oil from the water.

Petroleum emulsions are of the water-in-oil type, and comprise fine droplets of naturallyoccurring waters or brines, dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. They are obtained from producing wells and from the bottoms of oil" storage tanks, and are commonly referred to as cut oil, roily oil, emulsified oil and bottom settlings.

The object of my invention is to provide a novel, inexpensive and efficient process for separating emulsions of the kind referred to into their component parts of oil and water or brine.

Briefly stated, my process consists of subjecting a petroleum emulsion to the action of a treating agent comprising a sulfo derivative of certain higher aliphatic ketones. Such sulfo derivatives may have the acid sulfate group or the sulfonic acid group or the sulfo aromatic radical present. j

It is well known that variousfatty acids may be treated in various manners to yield ketones. Reference is made to Chemical Technology and Analysis of Oils, Fats, and Waxes, Lewkowitsch, sixth edition (1921) volume 1, pp. 146 and 153. If a ketone derived from fatty acids having at least 8 carbon atoms is treated with sulfuric acid monohydrate at a temperature of around 100 0., there is formed true sulfonic acids in the same manner as true sulfonic acids can be formed from fatty acids. Reference is made to U. S. Patent 2,037,974, dated April 21, 1936, to Guenther and Holsten. As to the formation of sulfonic acids under somewhat similar conditions from fatty acids instead of from ketones, reference is made to U. S. Patent 601,603, dated March 29, 1898, to Twitchell.

Such sulfonation process can be applied to substantially all fatty ketones of the kind described, and particularly to palmitone, stearone, etc. On the other hand, certain fatty ketones, such as oleone or erucicone, described by Lewko- Witsch, are characterized by the presence of an ethylene linkage in each of the two fatty acid residues which enter into the composition of the compound. Such ketones will react with sulfuric acid to form acid sulfates. These sulfates are not particularly stable, and during the washing process in which the excess of acid is removed, they are partially decomposed so. that the yield is only a fraction of the theoretical yield. This is comparable, of course, to the conventional sulfonation of a'material, such as oleic acid or olive oil. Such sulfonation, when conducted at about 35-45 C. and when washed in the usual manner, results in a product which contains not over one-third fatty sulfate. Similarly, when a fatty ketone such as oleone, is sulfonated or, more correctly, sulfated, in the manner employed for the sulfation of castor oil or olive .oil or oleic acid, in the manufacture of Turkey red oil or Turkey-red oil substitutes, one obtains approximately one-third to one-half the theoretical yield of corresponding acid sulfate. These compounds are acid sulfates and are not true sulfonic acids, and are decomposed by boiling in a dilute acid solution.

Similar ketones, such as hydroxy stearone, dihydroxy stearone, etc., are characterized by the presence of an alcoholiform hydroxyl, instead of an ethylene linkage. Such fatty ketones having an alcoholic hydroxyl present will react with sulfuric acid just as readily to give an acid sulfate as will materials such as oleone.

In some instances, one may have a fatty ketone such as ricinoleone, which is characterized by the presence of an alcoholiform hydroxyl, as well as an ethylene linkage.

A fatty acid capable of forming fatty acid sulfate such as oleic acid, erucic acid, ricinoleic acid, hydroxy stearic acid, etc., is also capable of forming a Twitchell reagent, which is sulfo aromatic fatty derivative. Similarly, fatty ketones of the type described which are characterized by the presence of an ethylene linkage or 'by the presence of an alcoholiform hydroxyl, or by both, can be united with aromatic residues to give sulfo aromatic compounds of such ketones which, as far as I am aware, are new compositions of matter and are described in my co-pending application for patent, S. N. 84,180, filed June 8, 1936.

Briefly described, such sulfo aromatic compounds of certain higher aliphatic ketones derived from fatty acids having at least 11 carbon atoms and not more than 22 carbon atoms, are indicated by the type formula in which R represents the radical R-".T.S0a.Z and R represents the radical R.T'.SO3.Z, in which R" and R' represent residues derived from fatty acids having at least 11 carbon atoms and not more than 22 carbon atoms in the chain and susceptible to sulfation; T and T represent aromatic residues derived from bodies susceptible to Twitchell condensation; S03 is the conventional sulfonic acid residue, and Z is an ionizable hydrogen atom equivalent.

If the fatty ketone is derivedfrom a single fatty acid such as oleic acid (for instance, oleone), then R" and R' are the same. If both aromatic residues are derived from the same aromatic body (forv instance, phenol), then. T and T are the same.

The fatty ketones may include those derived from various fatty acids, including linolic acid, linolenic acid, and the like. The ketones may be derived from hydrogenated ricinoleic acid, in which the hydroxyl is intact. Acetylated ricinoleic acid may be used in the formation of a ketone. Similarly, chlorostearic may be used in the formation of a ketone. The preparation of the higher ketones is usually conducted in the manner indicated by Lewkowitsch, to-wit, heating the fatty acids with iron filings to about 350 C.

In the manufacture of Twitchell reagents from fatty acids, the aromatic materials customarily employed are benzene, naphthalene, phenol, cresol, etc. Toluene and xylene are sometimes employed. Beta naphthol is sometimes employed. Tetralin may be employed. Anthracene, hydrogenated anthracene, or phenanthrene, have been founduseful in the manufacture of such sulfo aromatic fatty acids. These aromatic substances are characterized by the fact that they produce monosulfonic acids when treated with sulfuric acids of the proper strength and under proper conditions, and are also characterized by the fact that when such sulfonic acids are contacted with higher fatty acid sulfates, such as the acid sulfate derived from oleic acid, the condensation takes place presumably with the elimination of sulfuric acid. Aromatic compounds of this kind are commonly referred to as being susceptible to Twitchell condensation.

I have previously pointed out that fatty ketones of the kind described may be converted into true sulfonic acids. Such reaction may be conducted so that the sulfonic radical is introduced into either or both of the fatty acid residues which enter into the composition of the fatty ketone. Similarly, it has been pointed out that certain of the fatty ketones which are characterized by the presence of an ethylene linkage or an alcoholic hydroxyl or both, may be converted into a sulfonic acid derivative, or may be converted into a fatty acid sulfate, which is characterized by the presence of the H804 radical. Reference has been made to my co-pending application, S. N. 84,180, filed June 8, 1936, in which application I have pointed out that the same fatty ketones which are susceptible to sulfation may be combined with aromatic bodies of the kind susceptible to Twitchell condensation and condensed under conditions which permit simultaneous or subsequent sulfonation, so as to obtain sulfo aromatic derivatives of the fatty ketones, characterized by the presence of the T.HSO3 radical, in which T represents an aromatic residue.

My preferred reagent is a sodium salt having the composition (C17Ha4.OH.C6H3.NaSO3)2C0. It is prepared in the following manner:

Oleone, (C17H33)2CO, prepared by treatment of oleic acid with iron filings at about 350 C., is treated with sulphuric acid monohydrate at a relatively low temperature, approximately 10-35 0., until the product is converted into the di-acid sulfate of the composition (11H34HSO02CO. Similarly, phenol is converted into sulfonic acid in the conventional manner. It is unnecessary to separate either the sulfonated aromatic material or the sulfated ketone from the excess acid employed in sulfonation in one instance, and in sulfation in the other instace. The acid masses are mixed in such proportion that '700 pounds of (C17H34HSO4)2CO is mixed with 350 pounds of phenol sulfonic acid. This calculation is based on the assumption that all the oleone was QQnverted a temperature of about 30-35 into the hydrogen sulfate and that all the phenol was converted into phenol sulfonic acid. The above mixture is intended to combine two molecules of phenol sulfonic acid with one molecule of C17H34HSO4)2CO. After combining the two acid masses, the mixture is stirred cautiously at C. and the temperature raised carefully to slightly under 40 C., if need be, until condensation has taken place and a compound of the following composition formed: (C17H34.0H.C6H3-HSO3)2C0. If COndensation or combination does not take place readily enough, it may be desirable to add o-leum containing 20-25% sulfur trioxide in relatively small amounts, for instance, 5% by weight of the total acid mass. The reaction should 'go to completion within 10-30 hours, and in some instances is substantially complete within four or five hours or even less.

Completion of reaction can be determined in the following manner: A small amount of the acid mass is diluted with three or four volumes of water and boiled under refiux'condenser for approximately 30 minutes. It is then poured into a separatory funnel and the lower layer of dilute acid withdrawn. The upper oily layer is then diluted with a large excess of water and should produce a clear solution which indicates that the entire mass is water soluble, due to the formation of the compound and indicates that it is not a mixture of sulfo aromatic material and (C1'1H33)2CO. It is to be noted that any (C1'1H34HSO4)2CO which is uncombined is decomposed by boiling dilute acid and converted into the Water insoluble ketone. If the sulfo aromatic derivative is soluble in acid of the dilution used during the boiling process, then in such event, at the end of the boiling period the product gives a clear solution with out separation of any upper oily layer. The upper oily layer being water soluble, may, however, be salted out by the acid present during boiling, and therefore the step of separation and subsequent dilution is necessary.

At the completion of the reaction, the acid mass is diluted with approximately twice its vo1- ume of cold water and the mixture stirred until homogeneous. The mixture is allowed to sep arate and the lower layer consisting of dilute acid is withdrawn and discarded, the upper layer representing (C1'1H34.OH.CsH3.I-ISO3)2C0. It is then employed in its acid state or is neutralized in any suitable manner. It may be neutralized with such materials as sodium hydroxide, potassium hydroxide, ammonium hydroxide, or the corresponding carbonates or bicarbonates. It may be neutralized with such materials as calcium or magnesium oxides or hydroxides. It may be neutralized with a suitable amine, such as triethanolamine, butylamine, amylamine, benzylamine, cyclohexylamine, aniline, etc. Some of the products so obtained not only are soluble in water, but are also soluble in hydrophobe vehicles such as gasoline or kerosene. Some compounds may be oil soluble and rather insoluble in water. Salts of the heavy metals, such as iron, copper, and the like, can also be obtained if desirable. It is my preference to convert the material above described into the sodium salt having the com position (C1'7H34.0H.CsH3NaSO3)2C0.

Incidentally, it is known that pyrolytic decomposition of ricinoleic acid or castor oil causes the molecule to break at the hydroxyl position and yield a sulfonatable unsaturated fatty acid having 11 carbon atoms. It is understood that the expression. fatty" hereused. because the acid. thus 1 obtained inrsuchnpyrolysis is a lower a homologue of oleic acid, However, as far as I, am aware, thisacid doesnot occur naturally in any fat or oil. This particularacid, C11H20O2, of course, can be converted into acorrespondin'g ketone which can thereafter be converted into a sulfonic derivative or a sulfo-aromatic derivative of the kindpreviously described. It might be well to point out that if desired, in the manufacture of the sulfo aromaticderivatives, more thanone sulfonic residue may be introduced into a single aromatic nucleus, and that generally speaking, the presence of such additional sulfonic acid residues increases the water solubility of the compound;

I have previously pointed out that'various bases may be employed to neutralize the sulfo aromatic derivatives of: the fatty ketones. Needless to say, the same basic materials or similar materials may be used to neutralize the acid'sulfate derivatives or the non-aromatic sulfonic acid derivatives. Esters can be formed from any of the acidic materials by conversion into a sulfonchloride and subsequent reaction of the suit able alcohol, such as ethyl alcohol, methyl alcohol, etc., or by reaction with an alcohol such ascyclohexanol.

In a general way, oil solubility is increased in the manufacture of these various materials by increasing the number or size of'the aromatic residues, for instance, theintroduction of two aromatic residues instead of one and more particularly, by the introduction of polycyclic aromatic residues instead of. monocyclic. aromatic residues. The neutralization of the acidic hydrogen by means of high molecular Weight amines such as benzylamine, cyclohexylamine, amylamine, diamylamine, triamylamine, andthe like, increase oil solubility.

Water solubility is increased by adding as few aromatic residues as possible and by introducing more than one sulfo group into an aromatic residue or by employing a hydroxy aromatic such as phenol, instead of a non-hydroxy aromatic compound such as benzene, in the preparation of the sulfo aromatic derivatives. Neutralization with materials such as caustic'soda, potassium hydroxide, ammonium hydroxide, etc., tend to increase solubility.

The solubility of the sulfates or-sulfonates free from aromatic materials may be controlled par-- ticularly by use of asuitable base. The simpler bases, such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, etc., tend to increase water solubility, whereas, the higher amines, such as cyclohexylamine, diamylamine, etc., tend to decrease water solubility and increase oil solubility. Water solubility can be decreased and oil solubility increased. by neutralizing the material so as to obtain the calcium salt, magnesium salt, etc. This is also true in regard to the sulfo aromatic derivatives.

As previously pointed out, an acidic hydrogen atom may be present in the compound as such or it may be neutralized or esterified so that it is replaced by a metallic atom, ammonium radical, amine residue or radical, or by anorganic radical such as an alkyl radical or aryl radical. The expression ionizable hydrogen atom equivalent is employed to indicate such acidic hydrogen atom or its equivalent of the kind indicated.

I have previously pointed out that there are three distinct species, namely, sulfonic acids (non-aromatic), acid sulfates, and aromatic sulfonic acids, .whichcomprise the-broad genus, and whichil willirefer' to as sulfo materials or sulfo compounds of certain higher. aliphatic ketones.

It is to be pointedout that the superiority of the reagent or demulsifying agent contemplated in my process is based upon its ability to treat certain emulsions more advantageously and at a: somewhat lower: cost than is possible with other available. demulsifiers, or conventional mixtures thereof. It is believed that the particular demulsifying agents or treating agents herein described will find comparativel qimited application so far as the majority of oilfield emulsions are concerned; but I have found that such demulsifying agents have commercial value, as they will economically break or resolve certain oil field emulsions in a number of cases .demulsifying agent of the kind described above may be broughtin contact with-the emulsion to be treated in any of the numerous ways now em ployed" in the treatment of petroleum emulsions of the water in-oil type with chemical demulsifying'agents, such, for example, as-by introducing the treating agent-into the well in which the emulsion is produced; introducing the treating agent into a conduit through which the emulsion isflowing; introducing the treating agent into a tank in which the emulsion is stored; or introducing the treating agent into a container that holds a sludge obtained from the bottom of an oil storage tank. In some instances, it may be. advisable to introduce the treating agent into a producing well in. such a waythat it will become mixed with water. and oil'that are emerging from the surrounding. strata, before said water and oil enter the barrel of the well pump or the tubing up through which saidwaterv and oil flow to the surface of the ground. After treatment, the emulsion is allowedto stand in a quiescent state, usually in a settling tank,and usually at a temperature varying from atmospheric temperature to about 200 F., so as to permit the water or brine to separate from the oil, it being preferable to keep the temperature low enough to prevent the volatilization of valuable constituents of the oil. If desired, the treated emulsion may be acted upon by' one or more of the various kinds of apparatus now used in the operation of breaking petroleum emulsions, such as homogenizers, hay tanks. gun barrels, filters, centrifuges, or electrical dehydrators.

Conventional demulsifying'agentsemployed in the treatment of oil field emulsions are'used as such, or after dilution with any suitable solvent, such as water, petroleum hydrocarbons, such as gasoline, kerosene, stove oil, a coaltarproduct, such as benzene, toluene, xylene, tar acid oil, cresol, anthraceneoil, etc; Alcohols, particularly aliphatic alcohols, such as-methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc. may be employed as diluents. Miscellaneous solvents, such as pine oil. carbon tetrachloride, sulfur dioxide, extract obtained in the refin' ng of petroleum, etc. may be employed asdiluents. Similarly, the material or materials employedas thedemulsifying agent of our process may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents. Moreover, said material or materials may be used alone or in admixture with other suitable well known classes of demulsifying agents, such as demulsifying agents of the modified fatty acid type, the petroleum sulfonate type, the alkylated sulfo-aromatic type, etc.

It is well known that conventionaldemulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water-solubility. Sometimes they may be used in a form which exhibits relatively limited water-solubility and relatively limited oil-solubility. However, since such reagents are sometimes used in a ratio of 1 to 10,000 or 1 to 20,000 or 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed. This same fact is true in regard to the material or materials employed as the demulsifying agent of my process.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: v r

1. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)nA, in which n is the numeral one or two and A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z.SO4, Z.SO3, or Z.TSO3, in which Z is an ionizable hydrogen atom equivalent and T is an aromatic residue derived from an aromatic body susceptible to Twitchell condensation.

2. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)2A, in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z.SO4, Z.SO3, or Z.TSO3, in which Z is an ionizable hydrogen atom equivalent and T is an aromatic residue derived from an aromatic body susceptible to Twitchell condensation.

3. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)2A,'in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and Dis the group Z.SO4, in which Z is an ionizable hydrogen atom equivalent.

4. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D) 2A, in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z503, in which Z is an ionizable hydrogen atom equivalent and T is an aromatic residue derived from an aromatic body susceptible to Twitchell condensation.

5. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)2A, in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z.SO3, in which Z is an ionizable hydrogen atom equivalent and T is an aromatic residue derived from an aromatic body susceptible to Twitchell condensation.

6. A process for breaking petroleum emulsions of the water-in-oil type, which consists in sub- ,jecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)2A, in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z.TSO3, in which Z is an ionizable hydrogen atom equivalent and T is a monocyclic aromatic residue derived from an aromatic body susceptible to Twitchell condensation.

7. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (D)2A, in which A is a residue derived from a ketone of the formula type in which R is a hydrocarbon or alkoxy chain derived from a fatty acid having at least 11 and not more than 22 carbon atoms, and D is the group Z.TSO3, in which Z is an ionizable hydrogen atom equivalent and T is a phenol residue.

8. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a chemical compound of the formula type (C17H34.OH.C6H3N&SO3)2C0.

MELVIN DE GROOTE.

V i A., i in, CERTIFICATE OF CORRECTION.

Patent No. 2,078,654. April 27,

J MELVIN DE encore.

It is hereby certified that error appears in the of the above numbered patent requiring correction as follows: Page 1 second column, line 44, for "1? read H; page 2, first column, line 6 after the parenthesis and before the subscript "1'7" insert the letter and second column, line 5, insert a parenthesis before "0", first 000 rence; page 4, second column, lines 15-17, claim 4, strike out the W0;

printed speoif'icz to Twitchell condensation"; and that t read with these corrections therein that the Henry Van Arsdale Acting Commissioner of Patents \M V n V V V V V H N CERTIFICATE OF CORRECTION.

Patent No. 2,078,654.

MELVIN DE GROOTE.

It is hereby certified that error appears in the printed spec of the above numbered patent requiring correction as follows: second column, line 44, for "E" read R; page 2, first column, line 65, after the parenthesis and before the subscript "17 insert the letter C; and second column, line 5, insert a parenthesis before C,

"and T is an aromatic residue derived from an a omatic body sus to Twitchell condensation"; and that the se lo Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 13th day of July, A. D. 19%.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.