JP2002543061A - Method for producing and isolating a sulfonated internal olefin - Google Patents

Abstract

  (57) [Summary] This is a method for producing and recovering a sulfonated internal olefin, wherein the internal olefin is sulfonated to form a reaction mixture containing a sulfonated intermediate compound, and the reaction mixture is neutralized and hydrolyzed to obtain a hydroxy. A reaction product mixture containing an alkane sulfonate, an alkene sulfonate and a hydrocarbon oil is formed, and the hydrocarbon oil is separated from the product mixture by azeotropic distillation of the product mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] This application is filed under the title Process fo, published Jan. 30, 1996.
No. 5,488,148 to r Sulfonating Internal Olefins.

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to sulfonated internal olefins.
al olefins), and more particularly to a process for isolating the sulfonate of an internal olefin from a reaction mixture.

Description of the Prior Art Sulfonates of internal olefins are useful as widely used anionic surfactants. Methods for sulfonating internal olefins are well known and described in the prior art. Processes for sulfonating internal olefins are disclosed, for example, in the following documents: European Patent Application No. 0446971 A1; Cavali et al., Co.
mun. Jorn. Com. Esp. Deterg. , 23,1992,205
-218 and Roberts et al., Comun. Jorn. Com. Esp.
Deterg. , 22, 1991, 21-35. European Patent Application No. 04
No. 46971 discloses sulfonating an internal olefin having 8 to 26 carbon atoms in a falling film reactor with a sulfonating agent having a molar ratio of sulfonating agent to internal olefin of 1; The reaction is carried out with cooling means so that the temperature does not exceed 35 ° C., and then the reaction product obtained in the sulfonation step is used. It is disclosed that summing and hydrolysis can be performed. The sulfonation of the internal olefin is preferably carried out with sulfur trioxide. The cooling means is preferably water at a temperature below 35 ° C, more preferably in the range of about 0 to 25 ° C. Said sulfonation can be carried out batchwise, semi-continuously or continuously. The reaction is preferably carried out in a falling film reactor where the reactor is cooled by flowing cooling water over the outer walls of the reactor. The internal olefin flows downward along the inner wall of the reaction vessel, similar to SO ₃ . SO ₃ is nitrogen,
Diluted with air or any other gas that is inert under the reaction conditions.

[0004] The Cavalli et al. Document discloses that internal olefins are sulfonated by reacting internal olefins with SO ₃ , aging the product, neutralizing with sodium hydroxide, and then performing hydrolysis. Is taught that This Ca
Valli's reference states that the molar ratio of SO ₃ / olefin is 1.025 and that the SO ₃ /
It is specifically disclosed that the sulfonation can be carried out with 2.5% air, a flow rate of olefin of 14.5 kg / h and a cooling jacket temperature of 8-10 ° C. According to the Cavali reference, neutralization can be carried out using 28% sodium hydroxide at a flow rate of 70 kg / h, at a temperature of 30 ° C. and an average residence time of 30 minutes. The hydrolysis can be carried out at a temperature of 160 ° C. and an average residence time of 40 minutes.

[0005] Roberts et al. Disclose sulfonation of internal olefins in a tubular reactor using SO ₃ diluted to a concentration of 2.5% SO ₃ in air in a temperature range of 10 to 32 ° C. It is disclosed that it can be performed while cooling. In the sulfonation process, the flow rate of the olefin is 16.45 kg / h and the molar ratio of SO ₃ / olefin is 1.05. One of the obvious advantages of the method of the present invention is that
In the sulfonation of the internal olefin, an ordinary batch-type reaction vessel that does not require a special design can be used. Prior art researchers have generally employed falling-film reactors when trying to obtain good quality products in high yields using the internal olefins neat, or in any case A specially designed reactor had to be used. The method of the present invention eliminates the problems associated with special reactor design.

[0006] Recently, sulfonation of internal olefins has been performed under conditions that yield products that are rich in hydroxyalkane sulfonates and have low amounts of residual sultones, inorganic sulfates and free oil. . J. Stappersma,
H. H. Deuling and R.E. The title of Van Ginkel is "Hydr
oxy Alkane Sulfonate (HAS), a New Surf
actant Based on Olefins ”(JAOCS, 69
Vol. 1, January 1992), pages 39-43, describes the production of hydroxyalkanesulfonates from internal olefins in a falling film glass reactor under mild conditions. Using such a technique, it is possible to obtain products rich in hydroxyalkanesulfonates.

[0007] US Patent No. 5,488,148, which is incorporated herein by reference for all purposes, discloses a process for sulfonating internal olefins, which includes: The internal olefin is present in the substantially inert hydrocarbon solvent in an amount of about 5 to about 40% by weight, and the sulfonation is performed under well-known sulfonation conditions to produce the sulfonated intermediate compound
After the formation of onated compounds, neutralization and hydrolysis are then carried out to obtain a product mixture containing HAS and alkene sulfonate, which is recovered. The method disclosed in U.S. Pat. No. 5,488,148 also includes extracting the desired internal olefin sulfonate into the aqueous phase using an alcohol, such as isopropanol, and then purifying the aqueous phase with an inert carbonized solution. It is also taught to backwash with hydrogen, such as hexane, to remove any residual paraffin. Since the isopropanol and some residual hexane remain in the aqueous phase, it is necessary to recover the sulfonate of the internal olefin by evaporating the water, alcohol and hexane.

[0008] Accordingly, it is an object of the present invention to provide a method for producing and recovering sulfonated internal olefins.

Another object of the present invention is to provide a process for isolating a sulfonated internal olefin obtained by neat sulfonation of the olefin or by sulfonating the internal olefin in a hydrocarbon solvent. To provide.

[0010] It is a further object of the present invention to provide an internal olefin sulfonate isolation process that reduces the number of processing vessels required and does not require volatile removal and recycling.

Yet another object of the present invention is to carry out the sulfonation of the internal olefin neat,
An object of the present invention is to provide a method for recovering the obtained internal olefin sulfonate so as to significantly reduce the amount of free oil present in the internal olefin sulfonate.

[0012] These and other objects of the invention will become apparent from the description provided herein and the appended claims.

According to the method of the present invention, the general formula: R ₁ —CH ＝ CH—R ₂ , wherein R ₁ and R ₂ may be the same or different and each have from about 1 to about 1 carbon atom. An internal olefin represented by the formula: is sulfonated with a suitable sulfonating agent to form a reaction mixture containing a sulfonated intermediate compound. The sulfonated intermediate compound in the reaction mixture is neutralized and hydrolyzed to produce a product mixture containing hydroxyalkanesulfonate, alkenesulfonate and a hydrocarbon oil. The product mixture is subjected to azeotropic distillation with water to separate the hydrocarbon oil from the product mixture.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the process of the present invention, the sulfonation of an internal olefin is carried out neat or in a suitable stream in a suitable vessel in the form of a dilute solution in a hydrocarbon solvent. The reaction is carried out by using vaporized sulfur trioxide contained in heated air (generally heated air) and passing it through an internal olefin as a starting material. Generally speaking, sulfur trioxide is introduced such that the molar ratio of sulfur trioxide to internal olefin is from about 1.0: 1.0 to about 3.0: 1.0. Generally, the temperature of sulfonation is maintained in the range of about the freezing point of the starting internal olefin to about 30 ° C, preferably about 10 ° C.

The sulfonation reaction produces a reaction mixture containing an intermediate, which is a sulfonated compound, and generally comprises a basic substance, such as an aqueous solution of an alkali metal hydroxide, ammonium hydroxide or alkanol. The neutralization is carried out using an amine or another commonly used neutralizing agent in the same temperature range as the sulfonation reaction discussed above. Preferably, the neutralization is performed using an aqueous solution of an alkali metal hydroxide, for example, a sodium hydroxide solution.

To neutralize the sultones, the neutralized reaction mixture is heated to about 100 ° C.
The sultones can be refluxed at a temperature of from about 160 ° C to about 160 ° C for a time sufficient to convert the sultones to either hydroxyalkanesulfonates or alkenesulfonates. Alternatively, the hydrolysis is carried out by placing the neutralized reaction mixture in a pressurized stainless steel container at a temperature of about 100 ° C. to about 160 ° C. and converting the sultones to hydroxyalkanesulfonate or alkene. This can be achieved by heating for a time sufficient to convert to the sulfonate, but care must be taken to maintain the reaction mixture to be neutralized and subjected to hydrolysis at a pH of about 11 or higher.

By such a hydrolysis step, a product mixture containing a hydroxyalkanesulfonate, an alkenesulfonate and a hydrocarbon oil (free oil) is obtained. The product mixture is then subjected to azeotropic distillation with water. This can be conveniently carried out in a heated stainless steel vessel with magnetic stirring, and the internal temperature of the vessel is monitored by a suitable controller, which injects air as needed through a cooling coil.
Inject water into the container and take measures to allow steam to come out. Such azeotropic distillation is generally performed at a temperature of 100 to 160 ° C. under a pressure of about 15 to about 80 psig.
The water-oil azeotrope is condensed and weighed, and the same volume of water as the recovered azeotrope is introduced into the vessel. Using such an approach during the azeotropic process,
The volume of the mixture in the reactor is kept essentially constant.

The following non-limiting examples are provided for the purpose of illustrating the invention in more detail.

[0019]

【Example】

Example 1: internal olefin (90.62%) of the adulterated without internal olefins sulfonated C ₁₅ -C ₁₆ and C of ₁₅ -C ₁₆ paraffin (3
. 42%) and C ₁₅ -C ₁₆ aromatics (5.96%) and
An internal olefin blend sold by Augusta was used as a raw material for sulfonation. The reactor consists of a syringe pump, a glass chamber for vaporizing sulfur trioxide, a glass trap for trapping sulfuric acid, and a perforated glass plate base for feeding the air-sulphur trioxide mixture into the raw material for sulfonation. And a glass-made tubular reaction tank for sulfonation. Side arms of the reactor
m) supported the thermometer, which was kept in contact with the raw material.
A thermocouple was placed in the vaporization chamber and the acid trap, wrapped with a heating tape, and the tape was connected to a temperature controlling Variacs. The liquid sulfur trioxide was weighed and placed in an airtight syringe, and the syringe was fitted with a long needle for transfer from the syringe pump to the top of the vaporizer. The liquid sulfur trioxide is injected such that it flows down the inner wall of the vaporizer. The sulfur trioxide evaporates in the vaporization chamber to form an air-sulfur trioxide blend, which is then sent through another glass container, where the sulfuric acid droplets Was set at a slightly lower temperature so that air entrained. Next, the air-sulfur trioxide blend is passed through the raw material for sulfonation in the reaction tank for sulfonation, and then discharged from the reaction tank via an exhaust port. In this example, a paraffin (aliphatic hydrocarbon) was added to a sulfonation reactor having a volume of 150 ml at an air flow rate of 10-11 liter / min.
Content content of aromatics and C ₁₅ -C ₁₆ internal olefins 5.96 wt% was poured 50 g (212 mmol) of 3.42 wt%. 12.9 ml (318 mmol) of sulfur trioxide were injected into the vaporizer at an injection rate of 0.5 ml / min. The vaporizer was held at 290 ° F. The acid trap was kept at 270 ° F.
The temperature of the sulfonation reaction was maintained at about 25 ° C. by using a water-ice bath as needed during the reaction. The reaction mixture became thicker and darker as the amount of sulfur trioxide added increased. Immediately after the addition of sulfur trioxide is completed, the reaction mixture is efficiently stirred and decanted into a beaker containing a cold solution of 50.9 g (636 mmol) of a 50% by weight aqueous sodium hydroxide solution and 25 ml of water. I put it. An additional 50 ml of water was used to rinse the sulfonation reactor. The intermediate sultone was partially hydrolyzed by mechanically stirring the contents of the beaker at room temperature for about 40 minutes. The pH was maintained above 11 throughout. The reaction mixture was transferred to a sealed stainless steel cylinder and heated at 160 ° C. for 50 minutes to neutralize the remaining sultone. During this time, the pressure is about 7
Up to 7 psig. The final pH of the hydrolyzed product mixture is 1
It was confirmed that it exceeded 1. After cooling to ambient temperature, the pH was adjusted to about 8 by careful addition of concentrated sulfuric acid with good mixing. At this point, the product mixture containing the hydroxyalkanesulfonate, alkenesulfonate, hydrocarbon oil, sodium sulfate and water was a dark brown gel. Recovery of Sulfonated Internal Olefins and Removal of Free Oil The product mixture was led to a stainless steel cylinder having a capacity of about 400 ml. The cylinder is placed in a block controlled by Therm-O-Watch.
) And heated. The internal temperature of the cylinder was monitored by a controller, which injected air through a cooling coil as needed. Water was introduced from a stainless steel pressurized storage tank (provided with glass side arms) via a dip tube built into the cylinder lid. The vapor was vented through a needle valve outlet which was connected to a Claisen head fitted with a graduated cylinder and fitted with a cooling condenser at the top set at -2 ° C. The neutralized reaction mixture was heated with stirring in a sealed bomb to reach a final temperature of 160 ° C. The vent was carefully opened to some extent to release the steam. The pressure in the cylinder can be from about 80 psig to about 50
psig. The release was carefully adjusted so that no foam was discharged.
The water-oil azeotrope was condensed and measured in a graduated cylinder. Fresh water was forced into the reactor using a head pressure of about 80 psig. In this way, an amount of water equal to the volume of water distilled off and condensed in the measuring cylinder was introduced. This water was typically introduced in 15 ml increments. Using such an approach during this azeotropic stage prevents the volume of the contents in the reactor from changing too much. A total of 122 ml of distillate was collected over a 1.5 hour period. The amount of free oil confirmed was about 2 ml, which is the expected amount. No oil layer was seen in the newly condensed distillate. The final sample was a turbid tan to brown slurry which was cloudy at ambient temperature and was found to contain 28.4% by weight of active internal olefin sulfonate and 0.88% by weight of free oil. This translates to 3% by weight of free oil based on the active internal olefin sulfonate. As a comparison, the reaction mixture after neutralization but before azeotrope contained 27.6% by weight of sulfonated internal olefin and 1.54% by weight of free oil. This translates to 5.3% by weight of free oil, based on active internal olefin sulfonate.

This example clearly demonstrates that the process of the present invention can be used to sulfonate a neat internal olefin to produce a sulfonated internal olefin with a minimum free oil content. are doing. This also shows that the unreacted olefin can be reduced as part of the free oil so that the sulfonation of the internal olefin does not have to be forcibly completed.

Example 2 A raw material for sulfonation containing 13% by weight of an internal olefin in a C ₁₄ -C ₁₆ paraffin solvent was prepared. The sulfonation apparatus used for the sulfonation of this dilute mixture of internal olefins was the same as that described above except that a larger glass sulfonation reaction tank was used to accommodate a larger volume of the sulfonation raw material. It was substantially the same as the device described in Example 1. Additionally, due to the problem of foaming of the dilute solution at the beginning of the reaction, the air flow was initially set low and gradually increased to reach the desired level. Set the air flow to about 3 liters / minute,
500 g of the above-mentioned raw material for sulfonation was placed in a 1-liter glass reaction tank for sulfonation (
311 mmol). 19.0 ml (468 mmol) of sulfur trioxide were injected into the vaporizer at 0.5 ml / min. The vaporizer was set at a temperature of 290 ° F. The acid trap was kept at 270 ° F. The amount of air can be gradually increased as the sulfur trioxide reacts. The final desired flow rate was reached when the amount of sulfur trioxide introduced into the reaction mixture was 1 ml. The reaction mixture was kept at 25 ° C. during the injection of sulfur trioxide. After the addition of sulfur trioxide was completed, the reaction mixture was efficiently stirred and decanted into a beaker containing a cold solution of 74.6 g (933 mmol) of a 50% by weight aqueous sodium hydroxide solution and 200 ml of water. Injected. An additional 200 ml of water was used to rinse the tar from the sulfonation reactor and into the beaker. The mixture thus neutralized, which was a slurry, was mechanically stirred at room temperature for about 40 minutes.
The pH was maintained above 11 throughout. 400 ml of this neutralized mixture
In a sealed stainless steel bomb at 160 ° C. for 50 minutes. The maximum pressure determined was about 80 psig. Due to the larger volume, this step was accomplished in four batches. Care was taken that the slurry before splitting into these four batches was well mixed. It was determined that the pH of the hydrolysis product mixture containing the hydroxyalkanesulfonate, alkenesulfonate and hydrocarbon oil was above 11 without further addition of base. Next, the four batches were combined and neutralized. The pH was adjusted from 7 to 8 by careful addition of concentrated sulfuric acid at ambient temperature to produce a yellow emulsion. Recovery of Sulfonated Internal Olefins and Removal of Free Oil About １ ／ of the product mixture obtained in the hydrolysis step was transferred to the reactor described in Example 1 above for removal of free oil. The azeotrope was performed at 160 ° C. under about 80 psig. The volume of water introduced and collected in the reactor during 9 hours before the distillate no longer showed a separated paraffin layer was about 1.7 liters. After further reducing the volume in the reactor by 350 ml, it was cooled to ambient temperature and a second quarter of the product mixture was introduced. It took about 1.7 liters of water for 9 hours to azeotropically remove oil from this second part. Finally, about 276 g of the product mixture was dark brown to burgundy and transparent, with no visible oil layer. This slurry was confirmed to contain 15.8% by weight of active internal olefin sulfonate and 0.2% by weight of free oil, which is 1.7% by weight of free oil based on active internal olefin sulfonate. Is interpreted as

This example demonstrates that using the process of the present invention, dilute feedstocks of internal olefin sulfonates can be efficiently sulfonated to produce internal olefin sulfonate products with very low free oil content. are doing. This also indicates that the sulfonation reaction does not have to be forced to completion in order to obtain a product with low free oil content.

The description and examples given above illustrate selected aspects of the present invention. While considering such variations and modifications will be suggested to those skilled in the art, they are all within the spirit and scope of the present invention.

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Filler, Paul A. 78641 Lender County Road, Texas, USA, United States 180 201 (72) Inventor Gates, Frank, 78651-0003, Texas, USA McNeill Botts 3F Term (Reference) 4H006 AA02 AC61 AD12 BB11 BC10 BC11 BC18 BC31 BC51 BC52 BC53 BE43

Claims (8)

[Claims] 1. A method for producing and recovering a sulfonated internal olefin, comprising the general formula: R ₁ —CH ＝ CH—R _{2 wherein} R ₁ and R ₂ are the same or different Each of which is an alkyl group containing from about 1 to about 30 carbon atoms.] The sulfonating agent is used to sulfonate the internal olefin to form a reaction mixture containing the sulfonated intermediate compound. Neutralizing and hydrolyzing the sulfonated intermediate compound in the reaction mixture under conditions that produce a product mixture containing hydroxyalkanesulfonate, alkenesulfonate and a hydrocarbon oil; and Boiling distillation to separate the hydrocarbon oil from the product mixture. 2. The method according to claim 1, wherein the internal olefin is present in a hydrocarbon solvent that is substantially inert under sulfonation conditions and does not deleteriously affect the sulfonation of the internal olefin, wherein the internal olefin is a hydrocarbon solvent. About 8 to about 20% by weight in hydrogen solution
The method of claim 1, wherein the amount is in the range of 3. The method according to claim 1, wherein said sulfonation is carried out using gaseous sulfur trioxide as a sulfonating agent. 4. The method according to claim 1, wherein the neutralization is performed using a solution of an alkali metal hydroxide. 5. The method of claim 2, wherein said hydrocarbon solution comprises a mixture of paraffinic hydrocarbons. 6. The method of claim 1, wherein R ₁ and R ₂ are alkyl groups, each of R ₁ and R ₂ containing from about 4 to about 15 carbon atoms. 7. The method of claim 1, wherein said azeotropic operation is performed at a temperature of from about 100 to about 170.degree. 8. The method of claim 1, wherein said azeotropic operation is performed at a pressure of about 15 to about 80 psig.