CA1117973A - Sulfonation of crude oils with gaseous so.sub.3 to produce petroleum sulfonates - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Petroleum sulfonates are obtained by continuously contacting whole crude oil or topped crude oil with gaseous sulfur trioxide (contains as a diluent sulfur dioxide and light hydrocarbon vapor) in a reaction zone operated at a temperature of 120-250°F. and a pressure of 3-50 p.s.i.a.
The reaction product is then passed to a vapor-liquid separat-ing stage where a vapor stream is separated and a portion of it is recycled hack to the reaction zone; a liquid stream is separated from the separating stage and a portion of it is recycled back to the reaction zone. The remaining portion of the liquid stream is neutralized with a monovalent inorganic base to obtain the petroleum sulfonate. The petroleum sul-fonates are particularly useful to recover crude oil from subterranean reservoirs.
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Description

7~73 , This invention relates to composltions useful for injecting into subterranean reservoirs to recover crude oil therefrom and more specifically to petroleum sulonates obtain-ed by reacting aromatic hydrocarbon with gaseous SO3.
Petroleum sulfonates have been prepared by a variety of means, for example, sulfonated with sulfur dioxide (U.S. Patent

2,999,812), sulfur dioxide and chlorine ~U.S. Patent 2,197,800), cleum ~U.S. Patent 2,845,455~, and sulfur trioxide ~U.S. Patent

3,183,183). U. S. Patents 3,215,628 and 2,815,370 teach the use of specific hydrocarbon fractions. Other patents of lesser interest include U. S. 2,174,508; 2,800,962; 3,173,864; 3,308,068;
3,244,622; and 3,418,239.
The prior art suggests that whole crude oil can be sulfonated and used in oil production. (See U. S. Patents 1,822,271; 3,126~952; and 3,302,713 teaching the use of whole crude sulfonates in secondary-type oil recovery and U. S. Patents 2,798,851; 2,953,525; and 3,198,832 teaching the use of such sul-fonates in drilling muds). However, we are unaware of a teaching as to ho~ this can be done or any co~ercial use of such a process.
Specific teachings of which we are aware require the removal of the light and/or heavy ends and the use of only the middle cuts to obtain the petroleum sulfonates.
There are a number of reasons for ~ractionating crudes prior to sulfonation. Inter alia, it is difficult to obtain a marketable product from asphaltenes which tend to form tarry materials Which foul reactors and sometimes form coke-like deposits, Also, the lighk ends are often aliphatics or light aromatics Which will not produce the desired product.
2~ We have now discovered that commercially acceptable ~,; ~
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7~73 sulfonates can be prepared ~rom a variety of crude oils using our processes~ While ~e were surprised to be able to prepare sulfonates in good yields and wi~hout coking or the formation of tarry products, we were pleased when we found that the sul-fonates produced economic micellar sy,stems suitable for use in oil recovery.
The upcoming "energy crisis" puts our invention in context. T. M. ~effen ~Oil & Gas Journal, May 7, 1973, pp. 66-76) indlcates that 55 billions barrels of addi~ional crude can be recovexed ~ia tertiary recovery. Heretofore, tertiary recovery processes Csee U. S. Patents 3,254,714; 3,307,628; 3,504,744;
3,261,399; 3,497,0a6; 3,506,070, 3,354,953; 3,330,344 and 3,348, 661 -- most using petroleum sulfonate surfactants) have all proved unecono~ic because, inter alia, the cost of materials used made the processes uneconomic and the amounts of oil recovered were too small. Our process provides sulfonates at a price sufficiently low to aid substantially in the commercialization of tertiary oil recovery using secondary-type oil recovery techniques taught in the above listed patents.
According to the present invention, a substantially con-tinuous flow of sulfur trioxide in the gas phase, is reacted with a hydrocarbon which can be either whole crude oil or topped crude oil or mixtures thereof. The contack occurs in a reaction zone fed by a substantially continuous flow of said hydrocarbon at temperatures, pressures~ and other conditions as described hereina~ter, and is followed by neutralization and possible extraction of unreacted hydrocarbons. The invention thus offers the substantial advantage of being able to produce valuable 29 petroleum sulfonates rom crude oils without fractionation :. :
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,, , 7~3 (other than optional "topping" to remo~e lo~ boiling fractions, usually paraffinic and not very reactive). The simplicity of this technique permits the use o~ portable sulfonation facilities which can manufacture petroleum sulfonates in the oil field.
Thus, the present invention o~fers the opportunity to manufacture sulfonates for use in petroleum recovery by use of substantially untreated recovered petroleum with all of the attendant advantayes over existing techniques which require substantial refining prior to sulfonation, use of selected fractions of pe-troleum in order to provide sulfonates suikahle for preparation of micellar systems, and the transportation from the producin~ field to the refinery and then the sulfonation plant and thence to the point of use in the ~ield~
The petroleum sulfonates of the present invention are useful in a wide variety of applications, including the preparation of cleaning compositions, frothing agents for oil flotation, and other purposes to which petroleum sulfonates are conventionally put. However, the most preferred application of the products of the present invention is the preparation of micellar systems and emulsions, especially those useful or the recovery of crude oil from subterranean reservoirs. The petroleum sulfonates of the present invention can be substituted as the surfactants in the techniques taught in each of the petroleum recovery patents mentioned above under prior art. In many cases, no further modi-fications of the formulations taught in those patents will be necessary. Where greater or lesser amounts of the sulfonates of the present invention axe required, these amounts may be readily determined by routine trial preparation of micellar systems and ~3 routine evaluation of such systems, e.g., by core ~looding tests.

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L7~73 The drawing shows a preferred embodiment o~ the sul-fonation process wherein crude oil i5 first dried, then contacted with sulfur trioxide and a Nash compr~ssor is used to compress the effluent from the reaction zone. Sulfur dioxide (reaction by-product from the sulfonation reaction) and light hydrocarbon vapor ~light ends from the crude oil) act as diluents for the reaction. Excess sulfur dioxide is contacted with water and ammonia to convert the sulfur dioxide to bisulfite and sulfite salts and these salts are admixed with the ammonium sulfonate.
A portion of the liquid from the reactor separator is cooled and recycled back to the sulfonation reaction zone -- the residue of the liquid is neutralized with an aqueous ammonium hydroxide solution to obtain a substantially neutralized sulfonate stream. This sulfonate stream is then permitted to phase separate into an unreacted oil phase and a petroleum sulfonate phase which is thereafter cooled, contacted with sufficient ammonia to obtain a pH of about 7-1~ and is then filtered. The filtrate is admixed with a cosurfactant to obtain a micellar dispersion.
The unreacted oil from the settler is used to extract the heavier molecular wei~ht hydrocarbons from the light hydrocarbon vapor.
Starting Materials: Hydrocarbon Feed: - It is an important aspect of the present invention that whole crude oil or topped crude is sulfonated. Previous processes have sulfonated gas oils without achieving the simplicity of the present invention.
Crude oils which are particularly useful for the practice of the invention are those which are relatively high in aromatic content;
but, lubricating oil base crude~ ~low aromatic content) are also acceptable.
2q The crude oil may be substituted with non-interfering cb/

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'. ; ' '73 substituents, e.g., NO3, C12, SO4, etc., but will preferably be a hydrocarbon. Preferred crude oils are those with aromatic portions having molecular weiyhts in the range o~ about 200 to about 1000, more preferably about 300 to about 800, and most preferably about 350 to about 500. The aromatic content of the crude oil is preferably about 10 to about 95, more prefer-ably about 20 to about 80, and most preferably about 25 to about 50 weight percent aromatics as defined in American Petroleum Institute Project 60 Reports 4-7 entitled "Characterization o~
Heayy Ends of Petroleum". Texas crudes, Libyan crudes, Louisiana crudes, Wyoming crudes, ~ichi~an crudes t Illinois crudes, Oklahoma crudes, Mississippi crudes, and Canadian crudes, are particularly preferred as starting materials. Especially preferred are crude oils wherein the aromatic portion has an aliphatic/aromatic proton ratio o~ about 3 to about 20 and more preferably about

4 to a~out 18.
The "aliphatic to aromatic proton ratio" used in the specification is measured on a carbon tetrachloride solution of the sample using a 60 MHz nuclear magnetic resonance spectro-~0 meter. The basic technique has been described by V. H. Lutherand H. H. Oelert, Erdon and Rohle, 24, 216 (1971). All those protons which resonate with a chemical shift between 0 and 5 ppm from the tetramethylsilane internal standard are defined as aliphatic protonst whose which have a chemical shift between 8.2 and 5 ppm are defined as aromatic protons. The American Petroleum Institute Project 60 Reports 4-11 entitled "Character~
ization of Heav~ Ends o~ Petroleum" present data which show the polynuclear aromatic content of crude oil distillates from 29 Was$on~ Texas; ~ilmington, Califoxnia; Red Wash, Utah: Recluse, c~/ - 5 -, , .

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Wyoming; Prudhoe Bay, Alaska; Gato Ridye, California; Ponca City, Oklahoma; and Gach Saran, Iran. Other evidence for the presence of polynuclear aromatics in crude oil is scattered throughout the petroleum literature. I'he Chemistr~ of Petroleum Hydrocarbons, B. T. Brooks et al, Volume I, Reinhold, 1954 discusses the concepts prevalent prior to 1954. Since that time, additional wor] has been done on the higher boiling crude fractions utilizing sophisticated analytical instrumentation and today there is little doubt that polynuclear aromatics are present in crude oils.
Topped crudes, e.g., those having a portion of the hydrocarbons boiling below about 600F~ removed, can be utilized in place of the whole crude oil.
- The hydrocarbon feedstock is preferably dried to a water concentration less than about 1500 ppm and preferably less than 1,000 ppm and more preferably less than 500 ppm.
Too hIgh of a water concentration causes the formation of sul-furic acid with the SO3 and thus reduces the yield of petxoleum sulfonate; it also adversely influences the phase separation of unreacted hydrocarbon from the neutralized sulfonation mixture.
SO3 Diluent: The SO3 stream is diluted with gas, eOg., SO2 and light hydrocarbon vapor (can be refined light paraffins, light ends from the crude oil). Optionally, other gases such as air, nitrogen,natural gas, or other dry gases can be used. The ratio of the SO2 and light hydrocarbon vapor to the hydrocarbon feed is 0.01 to about 10, more preferably about .1 to about 6, and most preferably about 1 to about 2 moles of each of the SO2 and hydrocarbon vapor per 100 1bs of 2Q the h~drocarbon ~eed.
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The purpose of the diluent is to dilute the S03 in order to promote a more even sulfonation reaction, e.g., to reduce the amount of tri- and hiyher sulfonates produced.
Also, the S03 diluent is necessary to reduce the partial pressure of the S03 in the reaction zone. An upper limit of about 35 psi partial pressure of the S03 is generally pre-ferred while the desired level is down around 5 psi. If the hydrocarbon feedstoc~ is a topped crude oil ~i.e. very little light hydrocarbon vapor is present), then the concentration of ~0~ is preferably high to obtain a desired partial pressure of S03 in the reaction zone. While the S03 diluent will not ordinar-~1~ solubilize the sulfonates in the unreacted hydrocarbons, it has the addit~onal advantage of lowering the viscosity of the reactIon products.
Excess diluent from the vapor phase of the reactor separator is preferably scrubbed with water (can contain ions) containing a basic compound, preferably ammonia, to convert any S2 to tne salts thereof, e.gO bisulfite and/or sulfite. The salts can be admixed with the petroleum sulfonate productA The 2~ S02 scrubber is preferably operated at a temperature to keep at laast a majority of any hydrocarbon present as a vapor, i.e.
condensing hydrocarbon i~ the S02 scrubber is not desired~ Hydro carbon vapor from the S02 scrubber is preferably scrubbed with unreacted oil obtained from the phase separation of the unextract-ed, neutralized sul~onate mixture to extract higher molecular weight fractions from thiS stream. Thereafter the extracted, light hydrocar~on can be flared, etc. and the unreacted oil contain~n~ extracted hydrocarbons can be used in a refinery, 2~ etc.
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SO~ and Light Hydrocarbon Vapor Recycle: In a vapor-liquid separating stage the effluent from the reactor zone is separated into a vapor stream and a li~uid stream. ~t leas-t a portion of the SO2 Yapor stream [comprised of SO2 and light hydrocarbon vapor ~contains hydrocarbons having molecular weights up to about 125 and preferably the a~erage molecular weight is less than about 75]~ is recycled back to said reaction zone.
A portion of the li~uid stream from the reactor separ-ator is cooled to reduce its temperature by about 3 to about 50~F. and preferably about 5 to about 30 and more preferably about 8 to about 15F. Said cooled stream is recycled back to mix with the hydrocarbon stream being fed to said reaction zone.
Sulfonation Additives: To facilitate controlling the equivalent weight distribution in the product mixture obtained from the reactions of the invention, one or more sulfonation additives can be added. These additives may be used either in conjunction with or in the absence of the aforementioned diluent.
Such sulfonation additives are preferably aromatic hydrocarbons, olefinic hydrocarbons, or oxygenated hydrocarbons, and preferably have molecular weights in the range of about 200 to about 1000, or more preferably about 300 to about 800, and most preferably a~out 350 to~about 500~ Speclfic examples of such sul~onation addit~ves include oxo alcohol bottoms (this is an oxygenated hydrocarbon and is defined below), aatal~tic cycle oil ~defined ~n U. ~. Patent 3,317,422, Col. 1, lines 55 through 72), Ultra~
former ~olymer bott~ms ~mixtures of alkylated benzene and naphtha-lenes~, and axomatics (such as those produced by the process of U, ~. ~atent 3,31.7,422)~ The sul~onation additives can be used 2~ in amounts o~ about 0 to 20, preferably about 2 to about 15~ and cb`,'- - 8 -.
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7~3 more preferably about 4 to about 10 pounds o~ sulfonation additive per 100 pounds o~ h~drocarbon feedstock, i.e. crude oil or topped crude oil.
The sulfonation additives can conveniently be incorpor-ated into the hydrocarbon feedstock be~ore it is sulfona-ted.
Therea~ter, normal sulfonat1on reaction procedures are followed.
The sulfonation additives are generally sulfonated ~or sulfated, ln the case of oxy~enated hydrocarbons) and exit as part of the product mixture.
The "oxo alcohol bottoms" are specifically debcribed in the book "Higner Oxo Alcohols" by L. F. Hatch, Enjay Company, Inc., 1957. Analysis of a typical oxo alcohol bottoms is (taken from "Oxo Ether Alcohols," Industrial and Engineering Chemistry, Bartlett, Kirshenbaum and Missig, Vol. 51, No. 3, pages 257-258):

Molecular weight 269 Oxygen, % 11.1 Carbon, % 75.2 Hydrogen, ~ 13.7 ~ydrQxyl No., mg. KOHgb 204 Infrared spectra Et~er peak at 9 microns Yes Alcohol peak at 9.6 microns Yes a Determined by cryoscopic method.
b By acetic anhydride-pyridine back-titration.
The components within the oxo alcohol bottoms can be alkoxylated, e.g., about 1-50 moles of an alkylene oxide such as ethylene oxide, propylene oxide, e~c. can be usad. Examples of commer-cially available oxo alcohol bottoms are the C 8 Oxopolymer and C-10 Oxopolymer products of Houdry Process and Chemical Co., ~elaware City, Delaware; Monsanto oxo alcohols, e.g. oxo alcohol 29 100 and heavy oxo end~, Monsanto Company, St. Louis, Missouri, etc.
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Sulfur Trioxide: The sulfur trioxide useful with the present invention can be of the usual commercial purity though high purity or relatively crude materials may be used in special-ized circumstances where warranted by the desired products.
The sulfur trioxide should be preferably substantially anhydrous and should be ~ree ~rom substantial quantities of impurities which would cause deleterious side reactions. About 3 to about 30, preferably about 5 to about 15, and more preferably about 8 to about 12 lbs. SO3 per lO0 lb. of hydrocarbon feedstock is useful with this invention.
If the SO3 treat level is too hiyh, tarry by-products may be obtained. In addition, inefficient oil recovery may be obtained.
Reaction Catalyst- While no catalyst will generally be employed with the present invention, known sulfonation catalysts can be employed where desired.
Reaction Temperature: In order to obtain the preferred product, the sulfonation reaction temperature should be about 120 to about 250F., preferably about 145 to about 220F, and more prefera~l~ about 170 to about 190F. Temperatures lower than 120F. may cause pluggIng of the reactor (due to viscous, tarry by-products/ etc.) and temperatures higher than 250F.
may cause decomposition of the component(s) within the reaction product.
Reaction Pressure; Improved petroleum recovery is obtained when the pressure in the reaction zone is maintained in the range of about 3 to about 50, preferably about 9 ~o about 35, and more pre~erably ~bout 15 to about 25 psia. At pressures 2~ ~re~ter than 5Q psia, the partial pressure o~ the gaseous SO3 cb/ - lO -, ) , ,, .
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-is generally too high to obtain a desired product, i.e., the sulfonate is generall~ too hydrophilic for ef~icient oil recovery.
Also, at high pressures, large amounts of S03 diluent may be neede~ to obtain a desired level of S03 partial pressure.
Contact Time: The contact time between the hydro-carbon feedstock and SO3 contact time and the time the reaction mixture enters the separator will generally be within the range of about 0.01 to about 30 seconds, preferably about 0.1 to about 1~ seconds and more preferably from about .5 to about 5 seconds.
Reaction Apparatus: The preferred apparatus is a continuous flow tubular reactor having an inlet for admitting the hydrocarbon feedstock, plus any additive plus some recycle reaction products, an inlet for the SO3 stream, and a vapor inlet and an outlet. Streams should be in turbulent flow within the reaction apparatus.
A Nash pump (e.g. Hytor vacuum pump, Nash Engineering Co., Norwalk, Conn.~ is especially useful to compress the effluent from the reaction zone and transfer the effluent to a ~apor liquid separator treferred to in the drawing as the reactor 2~ separator). The compressor or pump should be sufficient to obtain a differential pressure of at least 0.01 psi and preferably at least a~out 0.1 to about 20 psi. Also, the differential pre-~sure s~ould be sufficient to cause the recycled vapor to enter t~e reaction æone and to become substantially dispersed in the ~O3 vapor stream.
The reactor is preferably made of stainless steel but any metal or nonometal having proper mechanical and corrosion-resistant properties may be utilized.
29 Neutralization; The sulfonic acid is neutrali~ed ~/ -- 11 -~J ' ~' ' ~ ' ' .
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'73 with a basic compound, e.g. sodium hydroxide, ammonia, a~noniurn hydroxide, etc. Preferably, the basic compound is diluted wtth water.
Extraction: ~ile not absolutely necessary to the practice of the invention, it is preferred to extract at least a portion (preferably paraffinic hydrocarbon) of the unreacted hydrocarbons from the sulfonate product. To accomplish this, the unextracted sulfonate mixture can be permitted to phase separate at temperatures up to about 275F. and preferably at about 125 to a~out 225 and more preferably about 150 to a~out 200F. Add'tives such as alcohols, acids, salts, water, etc. can be added to facilitate extraction of the petroleum sulfonate. Examples of useful alcohols include those containing l to about 5 carbon atoms, also semi-polar organic compounds such as ~enzène are useful.
The amounts of unreacted hydrocarbon and salt contents in the final petroleum sulfonate product can be controlled by the operating conditions of the extraction process, the extraction additive to unextracted sulfonate mix ratio and the extraction-additive composition. For example, about 0.8 to about 2.0 lbs., ~referably about 1.0 to about 1.8 lbs. and more preferably about l.l to a~out 1.5 l~s. of a~ueous alcohol solution or water can be admixed with each lb. o the unextracted sulfonate mix. A
preferred extraction additi~e composition is water containing ~bout 5~ to about 80% and more preferably about S5 to 75% by weight of isopropanol--this composition is preferred where the unextracted sulfonate mix contains about 15 weight percent ~ater.
~9 The mixture resultin~ after addition of the extraction cb/ - 12 : ,, ~, , . . , . :

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, , '' ' ' , " , additive will separate into either two or three phases; a raffinate phase which consists primarily of unreacted hydro-carbons, an extract phase which contains most of the petroleum sulfonate produc~, and possibly (depending on the particulax extraction solvent used) a brine phase which contains salts and water.
The raffinate phase can be processed, e.g. by stripp-ing, to recover any extraction additives and water from the unreacted hydrocarbon. The extract phase can be fed to a stripper to remove water and any lo~ boiling point additive ro~ the petroleum sulfonate product. The brine phase, if any, can be disposed of or can be further processed to recover salts, e.~., ammonium sulfate which can be utilized as fertilizer.
The petroleum sulfonate is preferably filtered to remo~e components which may tend to plug a subterranean reseryoir. The pH of the sulfonate is preferably adjusted to about 7 to about 10 before it is filtered.
Product Specification: The desired petroleum sul-fonate product has an average equivalent weight within the range ;~
20 of about 350 to about 525, more preferably about 375 to about 475 and most preferabl~ about 390 to about 445. This average equivalent weight range of the petroleum sulfonate is a major quality control parameter and is directly related to th0 capabil-ity o~ the petroleum 5ulfonate to impart micellar characteristics to mixtures of hydrocarbon and aqueous medium. The equivalent weight of the petroleum sulfonate is defined as the sulfonate molecular weight diYided by the average number o sulfonate gx~u~s per moleculeO It indicates the relative amount of mono-29 sulonation and pol~sulonation, i.e., the equivalent weight cb/ - 13 -, . .
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7~3 becomes lower as the polysulfonation increase~.

Pre~aration of Micellar Dispersion S~stems The micellar dispersion contains hydrocarbon, aqueous medium, and petroleum sulfonate. Optionally, cosurfac~ant and/or electrolyte can be incorporated. Examples of volume amounts include about 2% to about 90~ hydrocarbon, about 5~ to about q5~ a~ueous medium, about 4% to about 25% or more of the petroleum sulfonates ¢can be 50% active sulfonate), about 0.01 to about 20~ cosurfactant, and about 0.001 to about 5% (weight % based on aqueous medium) of electrolyte ~can be sulfite and/or bisulfites from the excess SO2 sulfates, etc.). The micellar dispersions can be oil-external or water-external.
The hydrocarbon of the micellar dispersion can be crude oil or partially refined fraction of crude oil, or refined fractions of crude oil, or synthetic hydrocarbons (including halohydrogenated hydrocarbons)O The aqueous medium can be ~oft or hard water containing minor amounts of salts, or brack-ish Water. The cosurfactant can be an amine, aldehyde, ketone, ~ydroxy-containing compound ~including conventional alcohols 2~ and ethoxylated alcohols), ester, ether, mixtures thereof, etc., containin~ 1 to about 20 or more carbon atoms. Numerous electro-lytes are useful, preferably they are inorganic acids, inorganic bases, and inor~anic salts. Examples of patents which teach the u~e of particular components useful in micellar dispersions include those defined l~n the prior art as well as others known ~n the art.
Tha micellar dispersion can optionally be composed of 28 two or more different petroleum sulfonates.

~b/ - 14 -EX~MPLES
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The following Examples are intended to more ~ully illustrate the invention and are not ko be considered as limitin~ the inyention in any way. Each o~ the Examples utilize the apparatus shown in khe drawin~. The process conditions are defined in the Examples.
Each of the sul~onates produced in Examples I and II
i~ utilized to produce a micellar dispersion ha~ing the com-position giyen in Table A. A certain number of pore volumes ~indicated under the respecti~e example) of the resulting micellar dispersion is injected into a 6" diameter core disc Ctaken from the Henry Reservoir, Crawford County, Illinois, U.S.A.). The core disc is prepared by first saturating it ~ith ~ater, then flooding oil therethrough, e.~., North Crawford Count~ ! S pipeline crude oil, Illinois Basic crude oil, to xesidual water Cthat is, until no more water is displaced from t~e coreL~ then Water flooded to residual oil ~that is until no additional oil is displ~ced from the core) using a simulated connate water. The water-flooded core disc at this point ~simulate$ an oil fleld a~ter conventional water flooding. A
slug ~the percent pore yolume is indicated under the respectlve exa~plel i~ then injected into the core to displace residual oil.
Injection of the micellar dispersion is followed by injection of lO~ PV (pore volume) of water containing llO0 ppm of Dow 700 pusher polymer (a partially hydrolyzed, high molecular weight polyacrylamide, Dow Chemical Co., Midland, Michigan) followed ~y 53% PV of water containing 615 ppm of Dow 700 Pusher polymer and this in turn followed by water containing 117 ppm of the 2~ pusher polymer - the water used is a simulated connate water.

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L75~3 The "oil recovery" is calculated as the volume percent of the residual oil in place after water flooding.

EXA~PLE I

Hydrocarbon Feedstock:
Type = Illinois Basin Crude Oil (Crawford County, Illinois, U.S.A.) 36 API @ 60F.
Rate = 1000 lbs. per hour H2O content = 800 to 2000 ppm H20 Reaction Conditions:
Type = Back mix tubular reactor ~ith liquid xecycle for temperature control and vapor recycle for SO3 dilution Liquid Recycle ratio = 4900 lbs./hr (i.e. 4.9 lbs.
per lb. Crude Oil)~cooled from 181F. to 162F.
in cooler) Temperature = 181~
Pressure = 18.8 p,s.i.a, SO3 Conditions:
~ ate = 100 lbs/~our Temperature of SO3 Feed = 268F~
Pressuxe = 28 p~s.i.a~
~O3 Diluent Conditions:
T~pe ' ~2 and li~ht h~drocarbons flashed from reactor e~luent Temperature ~ 179F.
~reSsure - 2005 p.~.i,a.
Rate ~ 270 lbs per hour ~i.e. 3.27 mole~/mole SO3) cb/ - 16 -:, "
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Composition = 51.9% SO2, 38.3~ Cl~C7 hydroc~rbon, 9.8% N2 from instrument pur~iny, average molecular weight ~ about 66 SO3 Partial Pressure in reaction zone - 4.4 p.s.i.a.
Sulfonation Additive:
T~pe - None Neutralization Conditions:
Reactor type = back mix ~low reactor ~2 sta~e mixer) Temperature = 162F.
~xessure = 45 p.s.i.a.
NH3 Rate = 26.5 lbs~hr.
~ater Rate _ 980 lbs!hr Phase Separation Conditions and Output:
Neutrallzation p~ = 5.5 - 6.5 Temperature = 162F.
Pressure = 13.1 p.s.i.a.
Time = 3.7 hours residence time in continuous settler Unreacted Elydrocarbon Rate = 604 lb/hr.
$ul~onate/5alt/Water Rate = 1455 lbs/hr.
~2 ~crubber Conditions:
Water Rate = 133 lbs/hr @ 132F.
NH3 Rate = 3 lbs/hr Brine (ef~luent, contains sulfite, etc.) Rate =
- 136 lbs/hr @ 155F.
Brine Compo~ition = 13.5 wt % salt reported as ~NH4~2SO4 Scrubber vent ~hydrocarbon vented) = about 10 lbs/hr.
(no hydrocarbon vent absorber Wa5 used) Micellar Solution ~efore ammonia or cosurfactant addition);
29 Rate = 1585 lbs/hr cb/ - 17 -:.;

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Composition = 3.82 wt % ~ SO3NH4 4.61 wt ~ salt reported as ~NH4)2SO4 69.0 wt ~ ~I2O
This micellar soluti.on was diluted with wa-ter to obtain the composition yiven in Table A. Also a cosurfactant was added Sulfonate Yield = 256 lbs/hr ~416 Eq. wt) ~.26 lbs/lb crude oil) Oil Recoyery = 58.2 vol % and 54.5 vol % of residual oil after water flooding using 6" Henry Disc cores from Crawford County~ Illinois, usin~ a 7% PV of micellar solution des-cribed in Table A followed by a 10% PV of 1100 ppm Dow 700 followed by 53% PV of 615 ppm Dow 700 followed by 117 ppm Dow 700 rollowed by Henry plant water.

EXAMPLE II

Hydrocarbon Feedstock:
Type = Illinois Basin Crude Oil ~Crawford County, Illinois, U.S.A.) 36 API @ 60F.
Rate = 750 lbs per hour ~1070 ppm H2O) Reaction Conditions:
Type = Back mlx tubular reactor with liquid recycle for temperature control and vapor recycle or SO3 dilution.

Liquid Recycle ratio = 5600 lbs/hour (7.43 lbs per lb Crude) (cooled from 181Fo to 168F~ in cooler) Temperature = 181F.
Pressure = 18.0 p.s.i.a.
.
cb~ - 18 -SO3 Conditions:
Rate = 59.5 lbs/hour Temperature of SO3 feed = 275F.
Pressure = 22.7 p.s.i.a.
Reaction Solvent Conditions:
Type = Llone SO3 Diluent Conditions:
Type = SO2 and light hydrocarbons from reactor effluent Temperature = 175F.
` 10 Pressure = 20.6 p.s.i.a.
Rate = 360 lbs/hour ~i.e. 7.3 moles/mole SO3) Composition - 66 average molecular weight SO3 Partial Fressure in Reaction Zone - 2.2 p.s.i.a.
Sulfonation Addit~ve:
Type = None Neutralization Conditions:
Reactor Type = back mix ,~low reactor ~2 stage mixer) Temperature - 152F.
~ressure = 47 p.s.i.a.
NH3 Rate = 14.7 lbs~hour ~ater Rate = 690 lbs/hour Neutrali~at~on pH = 5~
Phase Separation Conditions and Results:
Temperature = 154F.
Pressure = 13.1 p.s.i.a.
Time = 12 hours residence time Unreacted Hydrocarbon Rate = 466 lb/hr Sulfonate~alt/EI2O Rate = 1010 lbs/hr.
29 ~2 Scrubber Conditions:

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~75~3 Water Rate = 85.0 lb/hr @ 128F.
NH3 Rate = 2,0 lbs/hr Brine Rate = 87.2 lbs/hr @ 128F.
Brine Composition - 14.82 wt ~ salt reported as ~H4)2S04 Hydrocarbon vented from scrubber = about 7 lbs/hour (No hydrocarbon yent absorber was used.~
Micellar Solution ~before ammonia or cosurfactant addition):
Rate = lQ97 lbs~hour Com~osition = 3.38 wt ~ -S03NH4 4.21 Wt % salt reported as (~H4~2S04 68.1 ~t % H20 (NH4~2S04 was added to the sulfonate/salt/water solution instead of the brine to keep the ~03NH4 concentration at 3.38 wt %) Sulfonate Yield = 147 lbs/hr. ~416 average Eq. wt) 0.20 lbs/lb crude oil Oil Recover~ = 7~74 % PV recovers 70.5 vol ~ and 70.3 vol % in two separate runs, and 7~ PV
recovers 52.3 vol % in a third run.
The ~ame polymer u~sed in Example I is - used ~n each of these ~loods.

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~L75~3 TABLE A

MICELLAR DISPERSION COMPOSITIONS
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Wt %
Sulfonate Product-In Cosurfactant Example No. S03NH4 Salt Type Wt % Water Balance lS the I 3.5 4.4 primary 1.0 71.7 organic amyl alcohol portion II 3.4 4.2 primary 1.0 68.1 of the amyl sulfonate alcohol plus - crude oil It should be understood that the invention is capable of a variety of modifications and variations which will be made apparent to those skilled in the art by a reading of the specification and which are to be included within the spirit of the claims appended hereto.

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Claims (12)

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

1. A process for the preparation of petroleum sulfonate suitable for use in secondary-type recovery of petroleum, com-prising in combination contacting sulfur trioxide in the gas phase with a hydrocarbon selected from the group consisting of whole crude oil, topped crude oil and mixtures thereof in a reaction zone fed by a substantially continuous flow of said hydrocarbon, said hydrocarbon being contacted in said reaction zone with a substantially continuous flow of SO3 vapor stream comprising sulfur trioxide vapor, sulfur dioxide vapor and light hydrocarbon vapor, the temperature in said reaction zone being maintained at about 120° to 250°F., the pressure in said reaction zone being maintained in the range of about 3 to about 50 p.s.i.a.
the reaction time being from about 0.005 to about 30 seconds;
wherein each hundred pounds of hydrocarbon is contacted with about 3 to about 30 pounds of sulfur trioxide, with about 0.01 to about 10 moles of sulfur dioxide and with about 0.01 to about 10 moles of light hydrocarbon vapor; thereafter compressing the effluent from said reaction zone to a pressure of at least about 0.01 pounds per square inch higher than that prevailing in said reaction zone, thereafter separating a vapor stream and a liquid stream from said effluent in a vapor-liquid separating stage, recycling at least a portion of said vapor stream back to said reaction zone and recycling a portion of said liquid back to mix with said hydrocarbon being fed to said reaction zone, and removing the remaining portion of said liquid stream to a neutralization zone where it is reacted with a monovalent ?b/

inorganic base to obtain the petroleum sulfonate.

2. The process of claim 1 wherein the temperature in said reaction zone is about 145° to about 220°F.

3. The process of claim 1 wherein the pressure in said reaction zone is maintained at 9 to about 35 psia.

4. The process of claim 1 wherein the contact time bet-ween the initial contacting of the hydrocarbon with the SO3 vapor stream and the time the effluent enters the separation stage is about 0.01 to about 30 seconds.

5. The process of claim 1 wherein each 100 lbs. of hydro-carbon is contacted with about 5 to about 15 lbs. of sulfur trioxide.

6. The process of claim 1 wherein each 100 lbs. of hydro-carbon is contacted with about 0.1 to about 6 moles of sulfur dioxide and with about 0.1 to about 6 moles of light hydrocarbon vapor.

7. The process of claim 1 wherein the liquid stream from the effluent is cooled to a temperature of at least about 3 to about 50°F. below the temperature of the effluent.

8. The process of claim 1 wherein a portion of the vapor stream from the vapor-liquid separating stage is contacted with sufficient amounts of a basic, aqueous solution to convert any sulfur dioxide that may be present in the vapor stream to a salt and thereafter combining the reaction product of this stream with the petroleum sulfonate.

9. The process of claim 1 wherein the petroleum sulfonate is contacted with sufficient amounts of a basic material to obtain a pH of about 7 to about 10 and wherein the resulting product is passed through a filter and the filtrate used to obtain a micellar dispersion suitable to displace crude oil from a sub-terranean reservoir.

10. The process of claim 1 wherein about 0.1 to about 10%, based on the hydrocarbon feedstock, of an oxygenated hydrocarbon is added to the hydrocarbon before it is contacted with sulfur trioxide.

11. The process of claim 1 wherein the petroleum sulfonate is permitted to phase separate into an unreacted oil phase and a petroleum sulfonate phase, the latter being the desired petro-leum sulfonate product.

12. A process for the preparation of ammonium petroleum sulfonate suitable for use in secondary type recovery of petroleum, comprising in combination contacting sulfur trioxide in the gas phase with a hydrocarbon selected from the group consisting of whole crude oil, topped crude oil and mixtures thereof in a reaction zone fed by a substantially continuous flow of said hydrocarbon, said hydrocarbon being contacted in said reaction zone with a substantially continuous flow of sulfur trioxide vapor stream comprising sulfur trioxide vapor, sulfur dioxide vapor and light hydrocarbon vapor, the temperature in said reaction zone being maintained at about 145 to about 220°F., the pressure in said reaction zone being maintained in the range of about 9 to about 35 psia; wherein each 100 lbs. of hydrocarbon is contacted with about 5 to about 15 lbs. of sulfur trioxide, with about 0.1 to about 6 moles of sulfur dioxide and with about cb/ 24 0.1 to about 6 moles of light hydrocarbon vapor; thereafter compressing the effluent from said reaction zone to a pressure of about 0.1 to about 20 lbs. per square inch higher than the prevailing pressure in said reaction zone; thereafter separating a vapor stream and a liquid stream from said effluent in a vapor-liquid separating stage, recycling a portion of said vapor stream back to said reaction zone, cooling a portion of said liquid stream to reduce its temperature to 3 to about 50°F. and re-cycling this cooled liquid stream back to and mixing it with said hydrocarbon being fed to said reaction zone, and transfer-ing the remaining portion of said liquid stream to a neutralization zone where is is reacted with aqueous ammonium hydroxide to obtain the ammonium petroleum sulfonate.

13. The process of claim 12 wherein the temperature in said reaction zone is maintained at about 170 to about 190°F.

14. The process of claim 12 wherein the pressure in said reaction zone is maintained at about 15 to about 25 psia.

15. The process of claim 12 wherein the contact time from the time the hydrocarbon comes in contact with the sulfur tri-oxide vapor stream until the time the effluent enters the vapor-liquid separating stage is about 0.1 to about 10 seconds.

16. The process of claim 12 wherein each 100 lbs. of hydro-carbon is contacted with about 8 to about 12 lbs. of sulfur trioxide.

17. The process of claim 12 wherein each 100 lbs. of hydrocarbon is contacted with about 1 to about 2 moles of sulfur dioxide and with about 1 to about 2 moles of liquid hydrocarbon vapor.

cb/ 25 18. The process of claim 12 wherein the portion of said liquid stream from the separation stage is cooled to reduce its temperature to about 5 to about 30°F.

19. The process of claim 12 wherein the remaining portion of the vapor stream is contacted with sufficient amounts of an aqueous ammonium hydroxide solution to convert any sulfur dioxide which may be present in the vapor stream to sulfite and/or bi-sulfite and thereafter combining the product of this stream with the ammonium petroleum sulfonate.

20. The process of claim 12 wherein sufficient amounts of ammonia are admixed with the ammonium petroleum sulfonate to adjust the pH of the sulfonate to about 7 to about 10 and this stream is thereafter filtered and is then admixed with cosurfactant to obtain a micellar dispersion suitable for displacing crude oil from a subterranean reservoir.

21. The process of claim 12 wherein an oxygenated hydro-carbon is combined with the hydrocarbon before the hydrocarbon is contacted with the sulfur trioxide vapor.

22. The process of claim 12 wherein the ammonium petroleum sulfonate is permitted to phase separate into an unreacted oil phase and an ammonium petroleum sulfonate phase, the latter being the desired product.

23. An apparatus for the sulfonation of hydrocarbon com-prising in combination: a continuous flow reactor having a sulfur trioxide inlet, a liquid hydrocarbon inlet, a hydro-carbon vapor and sulfur dioxide vapor inlet, and an outlet, a source of sulfur trioxide connected to said sulfur trioxide inlet and a vaporization means upstream of the sulfur trioxide cb/ 26 unit to vaporize sulfur trioxide before it enters the reactor, a liquid hydrocarbon mixing zone connected to said liquid hydro-carbon inlet of said reactor, a source of hydrocarbon connected to said liquid hydrocarbon mixing zone, a vapor-liquid separator having an outlet connected to said hydrocarbon mixing zone, mixed-gas in liquid pumping means having a discharge pressure of at least about 0.1 psi greater than its inlet pressure and having an inlet connected to the outlet of said reactor and an outlet connected to said vapor-liquid separation zone, a re-cycling means connecting the vapor space of said vapor-liquid separator with said hydrocarbon vapor and sulfur dioxide vapor inlet of said reactor, a liquid recycle means connecting the liquid space of said vapor-liquid separator with said liquid hydrocarbon mixing zone, cooling means for cooling the liquid recycle from said vapor-liquid separation zone to said liquid hydrocarbon mixing zone, product outlet means for withdrawing a portion of said liquid from said vapor-liquid separator, and a neutralization reactor to substantially neutralize the liquid from said vapor-liquid separator with a monovalent inorganic base.

24. In a process for the recovery of crude oil from a subterranean reservoir having an injection means in fluid communication with a production means and wherein a micellar dispersion is injected into the reservoir and displaced toward the production means to recover crude oil therethrough, the improvement comprising utilizing a micellar dispersion comprised of a petroleum sulfonate obtained by the process of claim 1.

cb/ 27 25. In a process for the recovery of crude oil from a subterranean reservoir having an injection means in fluid communication with a production means and wherein a micellar dispersion is injected into the subterranean reservoir and displaced toward the production means to recover crude oil, the improvement comprising utilizing a micellar dispersion comprised of the ammonium petroleum sulfonate defined in

claim 12.

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