CA1095929A - Process for making ether sulfonates - Google Patents

Abstract

PROCESS FOR MAKING ETHER SULFONATES
(D#75,333-F) ABSTRACT OF THE DISCLOSURE
Covers a method of preparing ether sulfonates from alkoxylated alcohols by reacting said alkoxylated alcohol with an allyl halide in presence of a base to pro-duce an allyl ether and reacting said allyl ether with sodium bisulfite to produce said ether sulfonate.

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Description

BACKGROUND OF THE INVENTION

Field of the Invention .
This invention relates to an improvement of preparing ether sulfonates from alcohols. The sulfonate products are useful as detergents and as surfactants for enhanced oil recovery processes.
Des~ tion of the Prlor Art organic sulfonic acids and organic sulfonates are becoming increasingly important due to their use in the preparation of liquid detergents, particularly in the preparation of relatively salt-free detergents having good solubility characteristics. Even more recently, compounds - of this general type have been found to be useful materials when employed as surfactants for enhanced oil recovery processes. In one general scheme sulfonated materials are prepared by sulfonation processes employing concentrated sulfuric acid or oleum. However, using such strong acids leads to the obvious problems of corrosion and/or salt disposal and separation following neutralization of the final reaction mixture to produce salt by-products. In most instances, products containing substantial amounts of the salt cannot be usefully employed, and such salt must be removed.
To obviate the above problems, another method of preparing organic sulfonates involves reacting an organic alcohol containing at least one hydroxyl group with a hydroxy-containing alkyl sulfonic acid salt. Under appro-priate conclitions, the two compounds are condensed with formation of by-product water to produce an ether sulfonate.

A typical sulfonating (more properly sulfoalkylating) s~

reagent here is sodium isethionate also named as the sodium salt of 2-hydroxyethane sulfonic acid.
In many instances use of hydroxy-containing alkyl sulfonic acids or salts suc:h as 2-hydroxyethane sulfonic acid salt or other sulfonating reagents of this type involves one or more process difficulties. For example, in some instances the organic alcphol to be sulfonated and the sulfonating reagent of this type are not mutually soluble one in another. As one example, the hydroxy compounds may be liquids at reaction temperatures but are not solvents for the solid, crystalline sulfonic acid salts. Hence, one is faced with a reaction system consisting of both liquid and solid phases with attendant obvious problems.
In still other instances, reactions of the above type are difficult to control or are even uncontrollable in many instances. Thus, for example, excessive foaming may occur which cannot be practically controlled or eliminated.
It is important in controlling foaming to remove water by-product during the course of the reaction as such water is formed. However, resort to such well-known expedients as a2eotropic distillation of said by-product water has been found to be unsuccessful or minimally useful.
In yet other processeses involving the just described classes of reactants, prior art efforts were unsuccessful in that highly colored products were obtained.
Yellow, brown or other colored products when used for detergent use, for example, are unsatisfactory. The discolored product requires bleaching in order to compete with like generally colorless products, which bleaching step adds considerably to the cost of production. In still other instances, sulfonation processes of this type involving the above reactants cannot be or are difficulty temperature controlled. Lastly, in some situations the proposed prior art sulfonating process cannot be adapted to batch, continuous, or semi-continuous processes, which latitude of choice is extremely desirable.
It is therefore a principal object of the inven-tion to provide a process of preparing organic ethersulfonates without resort to a direct sulfonation process which method then avoids the just mentioned disadvantages of prior processes.
The specific object of the invention is to provide a method of making ether sulfonates fxom commercially available, inexpensive raw materials, which method can be carried out under relatively mild conditions and in excellent yields. A still further object of the invention is to provide a procedure which is egually adaptable to reaction with a wide variety of alcohol alkoxylates including alkyl, aryl, and alkaryl alcohols of this type.
The above-mentioned objects and advantages of the present invention will become apparent as the invention is more thoroughly set out hereinafter. -SUMMARY OF THE I~ENTION
In its broadest aspects, the present invention comprises a method of preparing ether sulfonates having the following structural formula:

R-~O-CH2-CH ~ O-CH2CH-CH2--S03A
Rl Rl where R is a radical selected from the group consisting of C - C alkyl, C2 - C30 alkenyl, Cl 30 alkyl, C2 - C30 substituted alkenyl, alkaryl c~ntaining one or more C1 -C18 alkyl groups substituted on said aryl group and aralkyl containing 7-28 carbon atoms, R1 is H or CH3,z is an integer of from 1-40 and A is an alkali metal anion, which comprises the steps of reacting an alkoxylated alcohol having the formula:
R--~O - CH2fH ~ OH
Rl where R, Rl, and z are as above with an allyl halide having the formula:
XCH2CRl=CH2 where X is halo and Rl is H or CH3 in presence of a base to.
produce an allyl ether having the formula:
R~O-CH2 ICH~o-CH2--CRl = CH2 Rl where R, R1 and z are as above and reacting said allyl ether with an alkali metal bisulfite such as sodium or potassium bisulfite to produce said ether sulfonate.
DESCRIPTION OF 1~ PREFERRED EMBODIMENTS
In more detail, a preferred method of preparing ether sulfonates involves preparing materials of the type having the formula:
RtO-CH2-CH ~ CH2cHRlcH2s3N
Rl where R is a Cl-C22 alkyl group, more preferably C12-C22, and most preferably mixed C16-C20, R1 is H or C~3 and z is an , . . i ~gs~

integer of from 1-40, more preferably l-10 which comprises the Step of reacting an alkoxylated alcohol of the formula:
R4O-CH2C ~ -OH

where R, Rl and z are as just noted with an allyl halide having the formula XCH2 CRl CH2 where X is halo and Rl is H or CH3 in the presence of a base to produce an allyl ether having the formula:
R~O-CH2 1 ~O~CH2CRl = CH2 and reacting said allyl ether with sodium bisulfite to produce said ether sulfonate.
Both allyl halides themselves and the methyl substituted allyl halides (methallyl halides) may be used as reac~tants, and thus by use of the term "an allyl halide" as used herein is meant a reactant to include both allyl halide and methallyl halide.
Another preferred method of preparing ether 20 sulfonates involves preparation of materials of the type .~;.
having the following structural formula~
~ 2 C\~I ~ O-CH~ CHRl CH2-SO Na Rl :
Rn

2~ where R is a C1 - C22 alkyl group, n is an integer of 1-3, Rl is H or CH3, and z is an integer of 1-40 which comprises the steps of reacting an alkoxylated alcohol having the formula:

~ O-CH2 CH)z o~

where R, Rl , n and z are as above with an allyl halide in presence of a base to produce an allyl ether having the formula:
~ O-CH2 CH~z O-CH2CHRl = CH2 where R, Rl, n and z are as above and reacting said allyl ether with sodium bisulfite to produce said ether sulfonate.
z more preferably is 1-10 and most preferably is 2-6. More preferably R is C6-C20 and most preferably is C8-C12.
Other alcohols which can be alkoxylated and then used as starting materials are arylalkanols, preferably containing a total of from about 7 to about 28 carbon atoms.
These may be represented by the following formula:

~n where R2 is an al~ylene group containing 1-22 carbon atoms, R is a Cl - C22 alkyl group and n is an integer of 1-3.
Polyether derivatives of these compounds may then be made by appropriate alkoxylation.
Thus, preferred alcohols which may be employed as reactants :in preparing alcohol alkoxylate materials are those having the general formula ROH, where R is a radical selected from the group consisting of Cl - C22 alkyl, C2 -C22 alkeny:L, substituted derivatives of these alkyl or alkenyl compounds, alkaryl radicals containing one or more Cl-C22, preferably Cl ~ C18 alkyl groups substituted on said 1~S!325~

aryl group, and aralkyl radicals containing 7-28 carbon atoms. When the alkyl or alkenyl groups contain further substituents, it is preferrecL that these be halo, nitro, cyano or lower alkyl (1-4 carbon atoms) groups which are non-interfering in the reaction sequence of the invention.
The starting alcohols which are alkoxylated by known procedures to produce the starting materials of the invention may be chosen from a wide variety of other readily available alcohols. Thus, for example, fatty alcohols preferably containing from about 8 to about 20 carbon atoms may be used and include such as lauryl alcohol, cetyl alcohol, tallow alcohol, octadecyl alcohol, and eicosyl alcohol and mixtures of these.
Still other useful alcohols here include the so-called Oxo alcohols from the oxo process, vinylidene alcohols, Ziegler-type primary linear alcohols prepared from trialkylaluminum mixtures made by way of ethylene polymerization, subsequent oxidation, and hydrolysis of the resultant aluminum alkoxides as set out in U.S. Patent No.

3,598,747 and other alcohols of this type. Typical vinyldene alcohols are set out in U.S. Patent 3,952,068 and have the general structure:
t 2 2 C~3-(CH2)X - CH(CH2)yCH3 wherein individually, x and y are numbers from l to 15 and the sum of x and y is in the range of 6 to 16.
Phenols and alkyl substituted phenols may also be employed here. Thus, for example, exemplary phenolic reactants include nonylphenol, dinonylphenol, cresol, and .

s~

the like. Particularly preferred are alkyl substituted phenolic compounds falling within the following structural formula:
~ OH
~.
R
where R is preferably an alkyl group containing ~rom 6 to 20 carbon atoms or a halo, nitro, or hydroxy alkyl substituted group of the same chain length (non-interferring group), and n is an integer of 1, 2, or 3. Most typically R in the above formula is a C8 12 alkyl group.
The starting materials used here then as reactant alcohols are those prepared by alkoxylating any of the above classes of alcohols or others. Thus, the a'bove compounds may be reacted with ethylene oxide or propylene oxide or mixtures ~hereof. When mixed oxides are used, they may be added to the hydroxy compound either sequentially to form block polyether compounds, or may be mixed and reacted simultaneously to form a random, or heteric oxyalkylene chain. The reaction of an alkylene oxide and a hydroxy compound is well-known to those skilled in the art, and the base-catalyzed reaction is particularly described in U.S.
Patents 3,655,590; 3,535,307 and 3,194,773. These polyether alcohols are well-known and may be prepared by any known process such as, for example, the processes described in 25 Encyclopedia of Chemical Technology, Vol. 7, pages 257-262, published by Interscience Publishers, Inc.
The first step of the process of the invention involves re~acting an alkoxylated alcohol of the type described above with an allyl halide. Preferred are allyl I

.

~5~

chloride, allyl bromide, methallyl chloxide and methallyl bromide. This step is carried out in the presence of a strong base such as an alkali metal hydroxide. Preferred are sodium hydroxide and potassium hydroxide. Generally the allyl halide and alkoxylated alcohol are reacted on a mole per mole basis, though an exce~ss of one reagent or the other may also be employed. The amount of base employed is also used in an equivalent amount and said amount usually ranges from about 0.85 equivalents to about 1.2 equivalents per equivalent weight of the alcohol employed.
The first step of the invention involving forma-tion of the allyl ether compound may be carried out over a wide range of process variables of time, temperature, pressure, etc. Usually, this step of the reaction is carried out at a temperature ranging from about room temperature up to about 250C. More often the temperature reaction is 25-200C and most often ranges from about 50C
to about 150C. The time of reaction likewise may be considerably varied from say about 1/4 to about 24 hours.
More often the reaction is complete in 1-10 hours. Again, the first step of the process of the invention may be run at atmospheric, superatmospheric or autogenous pressures.
Thus, for example, an autoclave may be used. Usually the pressure ranges from about 5 to about 500 psig. More often the pressuxe is 5-100 psig.
The allyl ether then in turn is reacted with sodium bisulfite to produce the desired ether sulfonate.
Oxygen must also be present here to carry out the reaction, and most conveniently is furnished via air as a vehicle.
The same conditions of time, temperature and pressure s~

applicable to the first step of the invention are also applicable here. This step of the invention is preferably carried out in presence of an aqueous media wherein at least 50 percent of the solvent is composed of water on a weight basis. Most preferably water itself may be employed.
However, a co-solvent system involving a water miscible organic solvent such as methanol, ethanol, isopropanol, methylethyl ketone, dimethyl formamide, and other solvents of this type mixed with water may also be employed.
The following examples typically illustrate the process of the invention. It is understood, of course, these examples are merely illustrative and that the inven-tion is not to be limited thereto.
EXAMPLE I
A mixture of 400 g of a 4 mole ethylene oxide adduct of nonylphenol, allyl chloride (76 g), and sodium hydroxide (40 g) was heated in a one-liter autoclave to 100C and held at that temperature for four hours. The crude reaction mixture was first filtered to remove solids, then heated to 70C under 25 mm pressure to yield a pale straw colored mobile liquid containing about 86% of the desired allyl ether.
ExAMæLE 2 A mixture of the allyl ether from E~ample 1 ~75 g), sodium bisulfite (35.4 g), isopropanol (150 ml), water (150 ml) and potassium nitrate (2 g) was heated for one hour at 100c and one hour at 120C under 20-37 psig of air.
Analysis indicated an 82% yield of the desired ether sulfonate.

A crude 3 mole ethylene oxide adduct of a mixed C16, C18, C20 linear alcohol (400 g) was charged to a one-liter stirred autoclave along with allyl chloride (95 g~ and sodium hydroxide (60 g). After heating for four hours at 100C, the crude material was filtered and then vacuum stripped to yield a low meltiny solia~ The solid was id~ntified as the desired allyl ether and was isolated in 89% yield.

The allyl ether of the 3 mole ethylene oxide adduct of the mixed cl6 cl8 c20 linear alcohol prepared in Example 3 (75 g) was mixed with sodium bisulfite (35.5 g), isopropanol (150 ml), water (150 ml) and potassium nitrate (2 g) in a one-liter autoclave and heated to 100C for one hour under 21 psig of air. The temperature was then increased to 122~C for another hour. Analysis showed a 81.6% yield of desired ether sulfonate.

The ether sulfonate derived from the four mvle ethylene oxide adduct of nonylphenol (Example 2) was tested for effectiveness in recovering oil beyond that recoverable by conventional techniques by the following core flood experiment.
Core: A 2 inch diameter by 6 inch long linear Berea sandstone core which had been fired to prevent clay swelling.
lBrine: A produced oil-field brine having a total dissolved ,solids content of 90,000 ppm, which included about 7,000 ppm calcium and magnesium ions.

... .

Oil: A West Texas crude oil diluted with n-heptane to achieve reservoir viscosity.
Surfactant Solution: 0.83% (w/v) of ether _ sulfonate plus 1.86% (w/v) of a 360 ecluivalent weight petroleum sulfonate in the above brine.
Polvmer Solution: 1,000 ppm Xanflood biopolymer in fresh water.
The core was prepared by first saturating it with the brine and then flooding the core with oil to the irreducible water saturation. It was then placed in an oven maintained at 109C and water flooded to a residual oil saturation of 31.8% pore volume. A 30% pore volume slug of the surfactant was then injected and followed by continuous injection of polymer solution. This reduced the oil saturation to 12.1%, which corresponds to a tertiary oil recovery of 62.1%.

A mixture of the alkylated nonylphenol o~ Example 1 (20 gms), water - 60 ml, isopropanol - 20 ml, Na~SO3 - 10 gms, and KNO3 - 1/2 cJm, was charged to a glass reaction vessel, heated at reflux for 5 hours under a constant air purge and then allowed to cool. Analysis of the resulting product inclicated the active ingredient, i.e., the sulfonate salt, was present to the extent of 0.034 mecL/gm.

The preceding example was repeated in all detail except that: no isopropanol was added as a solvent. Instead, the amount of charged water was increased to 80 ml to insure the same reactant concentrations. Again, analysis of the reaction produce indicated the presence of the desired active ingredient - 0.038 meq/gm.

.

In a somewhat similar manner to the experiments described in Examples 6 and 7, a mixture of an allylated-alkoxylated nonylphenol (75 gms), NaHS03 (35.4 gms), KNO3 (4 gms), and H2O (300 ml) was charged to an autoclave, pressured to 20 psig with air after heating to 100C.
Following a reaction time of 1 hour, the temperature was increased to 130C and the air pressure increased to approximately 80 psig. After 2 hours, subsequent analysis indicated the concentration of active ingredient to be 0.153 meq/gnL.

- It has been noted here that the above ether sulfonates involving use of an allyl halide itself are oftentimes contaminated by minor amounts of impurities believed to be bis-sulfonates or sulfinate-sulfonate mixtures. In an effort to minimize their formation, resort was made to use a more highly sterically hindered allylic halide, namely a methallyl halide to produce the corres-ponding more hindered ether sulfonate.
Specifically, the alcohol of Example 1 was reacted as follows. Under reaction conditions similar to those employed in Example 1 methallyl chloride (83.9 g, 0.93 mole), alcohol of Example 1 (400.0 gm, 1.0 mole) and sodium hydroxide (48.0 gm, 1.2 moles) were allowed to interact in an autoclave for 2 hrs. at 100C. The crude reaction mixture WZLS first filtered and the resulting filtrate stripped under reduced pressure thereby yielding a low viscosity (80 cp at 25C) slightly colored (Gardner color 7-8) material which exhibited a hydroxyl no. of 35.0 and ~s~

possessed a water content of 0.2 wt %. NMR and IR
spectroscopic data confirmed this material to be predom-inantly the desired methallylated derivative.
Conversion of the derivative described above to the desired sulfonate salt was readily accomplished via the sodium bisulfite addition technique. Thus, heating a mixture of methallylated a~cohol (75.0 gm, 0.166 mole), sodium bisulfite (35.4 gm, 0.34 mole) isopropanol (150 ml), potassium nitrate (2.0 gm~, and water (150 ml) under a positive pressure of air for 2 hrs. at temperatures between 100-120C gave rise to a crude reaction mixture which contained active ingredient corresponding to a 78.2% yield.
Analysis indicated that a material of higher purity was made compared to the runs of the previous examples.
The invention is hereby claimed as follows:

Claims (17)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of preparing ether sulfonates having the following structural formula:

where R is a radical selected from the group consisting of C1 - C30 alkyl C2 - C30 alkenyl, C1 - C30 substituted alkyl, C2 - C30 substituted alkenyl, alkaryl containing one or more C1 - C18 alkyl groups substituted on said aryl group and aralkyl containing 7-28 carbon atoms, R1 is H or CH3, z is an integer of 1-40 and A is an alkali metal anion, which comprises the steps of reacting an alkoxylated alcohol having the formula:

where R, R1 and z are as above with an allyl halide having the formula XCH2CR1=CH2 where X is halo and R1 is H or CH3 in presence of a base to produce an allyl ether having the formula:

where R, R1 and z are as above and reacting said allyl ether with an alkali metal bisulfite to produce said ether sulfonate.

2. The method of Claim 1 wherein said allyl halide is allyl chloride.

3. The method of Claim 1 where R1 is H.

4. The method of Claim 1 wherein R is a mixed C16 -C20 alkyl group.

5. The method of Claim 1 wherein said allyl halide is methallyl chloride.

6. The method of Claim 1 wherein said allyl ether is reacted with sodium bisulfite in the presence of an aqueous media.

7. The method of Claim 6 wherein said aqueous media contains at least 50 percent by weight of water.

8. A method of preparing ether sulfonates having the following structural formula:

where R is a C1 - C22 alkyl group, n is an integer of 1-3, R1 is H or CH3, and z is an integer of 1-40 which comprised the steps of reacting an alkoxylated alcohol having the formula:

where R, R1, n and z are as above with an allyl halide having the formula XCH2CR1=CH2 where X is halo is R1 is H or CH3 in presence of a base to produce an allyl ether having the formula:

where R, R1, n and z are as above and reacting said allyl ether with sodium bisulfite to produce said ether sulfonate.

9. The method of Claim 8 wherein said allyl halide is allyl chloride.

10. The method of Claim 8 wherein said allyl halide is methallyl chloride.

11. The method of Claim 8 wherein R1 is H.

12. The method of Claim 8 wherein said allyl alcohol is reacted with said sodium bisulfite in the presence of an aqueous media.

13. The method of Claim 12 wherein said aqueous media contains at least 50 percent by weight of water.

14. The method of Claim 8 wherein z is 1-10.

15. The method of Claim 14 wherein R is a C8 - C12 alkyl group and n is one.

16. The method of Claim 15 wherein R is C9, n is one, and z is 2-6.

17. The method of Claim 16 wherein R1 is H.