DE1917300A1 - Process for the production of alpha-olefin sulfonates which can be used for cleaning agents or detergents - Google Patents

Description

' PATENT LAWYERS

DR. E. WIEGAND DIPL-ING. W. NIEMANN 1917 300 DR. M. KÖHLER DIPL-ING. C. GERNHARDT

MÖNCHEN HAMBURG

phone: 39 5314 2000 HAMBURG 50, April 1st, 1969

TELEGRAMS: KARPATENT KDN IGSTRASSE 28

W. 23475/68 8 / Ne

Richard J. Brooks

and

Burton Brooks
both Seattle, Washington (V.St.A.)

Process for the production of (X -olefin sulfonates.

The invention relates to an improved process for olefin sulfonation and an improved process for neutralization and hydrolysis of olefin sulfonic acids and for sulfonation and neutralization of alcohol sulfates which are produced by sulfonation of o ( -olefins or unsaturated alcohols.

C ^ olefins and unsaturated alcohols can be useful sulfonate in order to be used as cleaning agents or detergents Products in a continuous air SO, sulfonation process to create. So is the usual method of generating such materials provided the use of reactors, in which the feed material on the wall of a long Jacket provided pipe flows down, where it is moved forward by a rapidly flowing SO ^ -air mixture. In a similar way The sulfonation products are way through the use of a

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a thin film-forming reactor "which brings about a film contact between the feed material and the SO ₃ -Air-Oemisch" and created by the additional use of a recirculation loop "which the necessary cooling of the OC-olefin or uns. alcohol-sulfonic acid after the Reaction brings about «in order to obtain the desired sulfonation products.

In the sulfonation of (X -olefins with a mixture of air and sulfur trioxide, two reactions take place, which can be represented as follows:

(1) RCH ₂ CH = CH ₂ + SO,

(2) RCH ₂ CH = CH ₂ + SO ₃

(3) Neutralization \

hydrolysis

RCH = CH-SO ₃ H + NaOH »RCH = CH-SO ₅ Na + H ₂ O

RCH-CH ₀ -CH ₀

ι y ^d

0-SO ₂ + HgO - ^ RCH-CH ₂ -CH ₂ SO ₃ H

OH RCH = CHCH ₂ SO ₃ H

It can therefore be seen that, in addition to producing the desired olefin sulfonic acid, sulfonation of CK olefins by the second reaction produces sultones which, after neutralization, must be decomposed by hydrolysis to give the desired (Y olefin sulfonates. Some of the same phenomena can occur in the sulfonation of unsaturated alcohols, in which both the hydroxyl group and the double bond can be sulfonated, in a manner similar to the sulfonation of olefins.

Accordingly, procedures for the production of oC - olefin sulfonates are and uns. alcohol sulfonates have been developed, which the sulfonation and neutralization of the reaction

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products of the sulfonation reaction and subsequent hydrolysis of the neutralized product include a decomposition of the sultones produced during the sulfonation. With regard to sulfonation, it has been found that the correct molar ratio of. SO, to olefin, the correct cooling water temperature and some digestion of the Olefinsulfonic acid before neutralization products of high Provide yield, good solubility and good color. With reference on the neutralization it has proven to be advantageous an excess of neutralizing agent in the neutralization zone, such as sodium hydroxide, potassium hydroxide or the like., to use so that the excess of the neutralizing agent above the amount needed to neutralize the olefin sulfonic acid it is necessary to divide the split or dismantled SuIton into neutralized by the hydrolysis reaction.

The hydrolysis of the sultone, which yields a mixture of oxysulfonates and alkene sulfonates, has been carried out in continuous operations. The amount of alkene sulfonate produced during hydrolysis is generally a factor of the temperature used, with the amount of alkene sulfonate increasing as higher temperatures are used. In general, the hydrolysis has been carried out under pressure in a jacketed vessel in which the sulphonate and sultone slurry is heated by means of a jacket surrounding the vessel. However, it has been found that in such a procedure the viscosity of the sludge increases unexpectedly high as the temperature in the vicinity of the jacket increases. In fact, it has been believed that sludges with a solids content above 43 % cannot be used, as gelation of the sludge occurs during neutralization and hydrolysis. Accordingly, when operating at higher temperatures, at which hydrolysis occurs at a greater rate, a noticeable problem becomes related

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encountered oil formation and excessive sludge viscosity «Vl

There has long been a desire in the industry for j a new and improved means of neutralizing and j hydrolyzing OC -olefin sulfonates in such a way that the problems associated with the known processes are eliminated. Such a system has now been developed in accordance with the invention, in which the problem of excessive sludge viscosity during neutralization and hydrolysis is controlled or eliminated and sludges with higher pesticide content can be used. According to the invention, this has been achieved in that the neutralization is carried out at a temperature of 45 to 54.degree. C., which is followed by a heat exchange before the hydrolysis takes place at a temperature of 88 to 154.degree. Similarly, this result has been obtained by optionally neutralizing the reaction product is brought about the sulfonation of OC-olefins at a temperature of 82 to-116 ⁰ C.

Accordingly, it is a primary purpose of the invention to provide a new one To create processes for the production of OC -olefin sulfonates, which are the shortcomings inherent in the known processes and eliminates disadvantages.

Another purpose of the invention is to provide a method to create sulfonation of olefins, which has a high yield and good solubility and a results in good color of the product.

Another purpose of the invention is to provide a new process for the neutralization and hydrolysis of the by sulfonation of CX olefins produced sulfonation products to create what the disadvantages of excessive Sludge viscosity and gel formation, as is the case with known procedures occur.

Another purpose of the invention is to provide a new process in which the sulfonation pro-

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domestic product, which is produced by the sulfonation of CK-olefins, is neutralized at a temperature of 43-54 ⁰ C and subsequently heated and hydrolyzed at 88 to 154 ° C. ·

Another purpose of the invention is to provide a to provide an improved process for the neutralization and hydrolysis of olefin sulfonation products, in which the neutralization is carried out at a temperature of 82 to 116 ° C.

Another purpose of the invention is to sulfonate unsaturated alcohols in such a manner and neutralize so that high sulfonate yields result and a shift in the pH value after neutralization is prevented.

Other purposes and advantages of the invention will become apparent from the description below.

The invention comprises an isulfonation reaction in which an of-olefin is sulfonated, for example by using a mixture of air and sulfur trioxide. According to the invention, (X -olefins are sulfonated by adding air and sulfur trioxide to the reactor, the molar ratio of sulfur trioxide to olefin generally being in the range 1.10 to 1.25: -1. It has been found that This molar ratio of sulfur trioxide to olefin results in full conversion of the olefin into the OC-olefin sulfonic acid and silt, which must be further broken down by hydrolysis in order to obtain the desired surface-active material it is necessary to use a sufficiently high ratio of 80-7 to olefin to ensure maximum reduction of the fed olefin to olefin sulfonate.

The temperature of the sulfonation reaction is controlled by the The fact that at very low temperatures the acid becomes excessively thick and therefore insufficient Ee-

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Stirring the reactants enables the desired Produce product. Moreover, it has an excessive increase the temperature tends to discolor the product, whereby the purity of the desired sulfonate is reduced. The cooling takes place in a film-forming reactor instead of through the wall of the reactor by means of a cooling jacket. It has been found that an optimal Cooling of the olefin sulfonic acid takes place when the cooling water has a temperature in the range of 4 to 21 ° C ·. The colder water is near the top of the reactor and used the warmer water further down. The product is cooled even further after leaving the reactor in a recirculation system in which the one leaving the film reactor Product is immediately cooled in a large recycle amount of cold acid. Accordingly it has been found that in the recirculation system cooling temperatures of about 32 ° C to about 49 ° C used advantageously with optimal results can be.

It is also advantageous to use the sulfonation product to digest for about 1 to about 5 minutes after leaving the reactor. The digestion of the sulfonation product provides a product of improved solubility compared to a product which is released immediately of the SuIf onierungsr eakt or s is neutralized .. This is due to the elimination of the more soluble oxysulfonates probably due to a rearrangement of the Sulton.

According to one embodiment of the invention, it has now been found that a region of minimum viscosity of the neutralized sludge at 43 occurs to 5.4 ⁰ C. Accordingly, in accordance with this embodiment of the invention, the basic neutralization of the olefin sulfonic acid takes place in the temperature range of 43 to 54 ° C, since it has been found that both below 43 ° C and above 54 ° C the viscosity of the system becomes considerably greater. At this temperature

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a decomposition of the sultone follows only to a minimal extent, so that in this case ts is a viscosity minimum of the Sultone acts. Generally speaking, sultones have a higher viscosity than the alkene sulfonates.

After the neutralization process in which the sulfoneture, etc. with sodium hydroxide, potassium hydroxide or the like. is neutralized, the neutralized product is heated to a temperature of 88 to 154 ⁰ C in a heat exchange system. The heating of the neutralized product takes place at a considerable rate "in order to achieve a good heat transfer" when the sludge passes through the high viscosity range with an increase in temperature.

The heated sludge is then passed through a hydrolysis coil or a hydrolysis tank, in which the temperature is maintained at the aforementioned value of 88 to 154 ⁰ C for a period of a few minutes to an hour or more »with a period of about 1/2 One hour at a temperature of about 14 ° C. is generally sufficient to bring about the desired hydrolysis. After hydrolysis, additional sulfonic acid or sulfuric acid can be added to the sulfonate product in order to adjust the pH to a value suitable for normal cleaning or cleaning. Detergent compositions useful. In general, after hydrolysis and the addition of sulfonic acid, a final pH in the range of 6 to 10 is desired.

The suifonation process used according to the invention is, is in Flg. 2 of the drawing schematically illustrates. The olefin and the sulfur dioxide mixed with air flow concurrently down the wall of the film-forming reactor. Cooling water is in the upper part of the Reactor allowed to operate at a temperature of 4.5 to 10 ° C, however, as sulfonation proceeds and the olefin is converted into the more viscous acid, the cooling water is supplied at a temperature of 16 to 21 ° C. After a very

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For a short reaction time in the reactor, the acid is cooled by bringing it into contact with a reflux stream of cold acid (52 to HO ⁰ C), followed by digestion for 1 to 5 minutes. During this digestion there is a rearrangement of the sultone structure, so that a more soluble product is obtained after the neutralization. After digestion, the product is neutralized.

As illustrated in Figure 1, an excess of a neutralizing agent such as a caustic agent enters a neutralizer 14 via a line 10, while the olefin sulfonic acid or an analogous material from the

»The sulfonation reaction enters the neutralizer 14 via a line 12. The molar ratio of the neutralizing agent to the sulfur trioxide fed to the sulfonation generator is 1.02 to 1.05 J 1 · As already noted above, the temperature in the neutralizer 14 is kept at a value of 4 to 54 ^° C., in which a Return through a heat exchanger 38 takes place, this temperature range being selected because it corresponds to a range of minimum sludge viscosity.

The product exiting the neutralizer 14 is pumped through a heat exchanger l6 by means of a pump 40, in which the temperature of the neutralized sludge is increased to 88 to .159 ° C by heat exchange with superheat | system water vapor is increased, which enters via a line 18 and exits as condensate via a line 20.

The heated neutralized sludge then enters one A hydrolyzer 22 in which the sultone present in the sludge is decomposed by hydrolysis to a desired one generate surface-active material. The hydrolysis temperature is maintained by means of indirect steam, which enters the hydrolyser 22 via a line 24 and emerges from it via a line 26. The ones in the hydrolyzer 22 hydrolysis is carried out under alkaline conditions,

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because hydrolysis under acidic conditions quickly becomes irreversible Color changes and corrosion of the facility. During the hydrolysis, the temperature of the Sludge not increased; that fed in during the hydrolysis Heat is only sufficient to absorb the heat loss that occurs during hydrolysis of the heated neutralized sludge to compensate.

Since the hydrolysis has to be carried out under pressure at temperatures above 100 ^° C., the product leaving the hydrolyzer 22 is passed through a pressure relief valve 28, which releases the pressure under which the system was operating during the hydrolysis. The reduction in temperature can generally be brought about, in part, by simply allowing some of the water vapor to escape from the product. Additional cooling can also be effected by means of a cooler 4l, if this is desired.

The product then passes through a container J> 6 and a pH sensing and controlling device JQ which measures the pH of the product to enable the manufacture of a final detergent product having a pH within the range , which is generally used for cleaning agents and detergents. A pH of from about -6 to about 10 is generally preferred. Accordingly, to maintain a pH in this range and to neutralize any excess caustic present in the system, additional sulfonic acid or sulfuric acid is added to the system via line J54 into tank J6 by opening one valve J2 located in line J4 in response to the pH value measuring device J> 0. The addition of sulfonic acid to the system via line 34 is generally required due to the fact that an excess of neutralizing agent, such as a caustic agent, is present in the system.

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is turned. Thus, the caustic added to neutralizer 14 will generally be in excess of that required to neutralize all of the acid exiting the sulfonation generator. In general, an excess of about 2 to 5 % is used, which leaves a certain excess after hydrolyzing the sultone.

Generally, a portion of the neutralizer 14 leaving product returned via a line 39. Around within the main return loop a maximum pump

^ To maintain speed, it is advantageous to regulate the temperature in the return loop to a value within the range of 43 to 54 ⁰ C, since this range is one that corresponds to a minimum sludge viscosity.

In accordance with the invention, it has been found that a region of reduced sludge viscosity also occurs at a temperature of 82 to 116 ^° C. Accordingly, in an optionally applicable procedure according to the invention, the neutralization of the product obtained from the sulfonation reaction is brought about within this temperature range. In this temperature range from 82 to 116 ° C, the sludge viscosity is lower than the sludge viscosity at the temperature.

ψ turbereich 43-54 ° C, and therefore it is possible to neutralize substantially higher Peststoffgehalte. This lower viscosity can be explained by the decomposition of a substantial percentage of the sultones in the short period of time in which the material is in the neutralization system, ie the pump 40, the heat exchanger 38 and the line 39. Since the sultone decomposition products have a lower viscosity, products with considerably higher levels of pesticides can be made. Another advantage of the higher temperature and the greater sultone decomposition is that most of the excess

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caustic agent is consumed, and it can now be one pH indicators 42 are used to adjust the amount of caustic introduced through line 10 Means to support.

Since the electrodes of the pH indicator 42 ^{cannot function properly above 82 °} C., it is desirable to cool a small stream of neutralized product by means of a heat exchanger 4j before it passes through the pH indicator. To minimize heat loss from neutralizer 14, the flow through heat exchanger 42 and pH indicator 42 is kept small. A.

As already mentioned above, the invention relates in particular to the sulfonation of OC-olefins which, after neutralization, require hydrolysis due to the formation of sultones during the sulfonation. Such OC-olefins generally contain at least 12 carbon atoms, and preferably about 12 to 20 carbon atoms per molecule. Examples of OC -olefins which can be used in the process according to the invention are: 1-dodecene, 1-tetradecene, 1-heptadecene, 1-hexadecene, 1-octadecene, 1-eicoses etc. Of course, mixtures of such OC -Oleefins and individual OC-olefins are sulfonated according to the procedures according to the invention. An example of a commercially available product is a mixture of 0.1-0.0 CX-olefins. \

Similarly, suitable unsaturated alcohols can include about. 10 to 20 carbon atoms in the process according to of the invention can be used. Attack such alcohols are: sperm alcohol, oleyl alcohol, etc., which have an iodine number of 50 to 80. It is desirable to have the hydroxyl group and not the double bond to sulfatio'en. These sulfates are more unsaturated Alcohols have the advantage of improved solubility. The alcohols are in a film-forming reactor sulfated, using cooling water at about 21 ° C

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the temperature of the alcohol sulfuric acid in a quench cooling system to about J / 2. or at most only a few degrees * above their freezing point. A molar ratio of sulfur trioxide to alcohol of about 1.15 t 1 gives good yields of alcohol sulfate, with about 12 % of the double bonds being sulfated at this molar ratio.

It was found that if normal neutralization temperatures were used in the range from jj8 to 54 ° C, the pH was shifted very quickly into the strongly acidic range. On the other hand, when the neutralization at 93 to 105 ° C, the unstable structures, ^ Esters and sultones decomposed, the pH remained unchanged after neutralization very stable, and there was a slight decrease in the free oil content. After neutralization at the high temperature, no further hydrolysis as in the olefin sulfonation was necessary.

The process according to the invention is explained in more detail below by means of some specific examples.

'· <■■■ - example 1

! A mixture of oC-olefins of the Cjc-Cjo

sulfonated. The mixture of olefins supplied by Chevron Chemical Company had approximately the following composition: Oi -olefins. . ... 89 %

| Olefins with an internal double bond 1% Diolefins 2 %

saturated connections 2 '$> ......

Average molecular weight 244 The sulfonation was in a film-forming sulfonation reactor, which allowed a uniform distribution of the olefin reactant on the reactor walls, using a 10 to 25% excess of sulfur trioxide over the amount that is theoretically required to produce the olefin sulfonic acid, at one concentration from 2.5 to 5.5 % SO, in air. The reactor

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cooling water was fed at a temperature of 16 to 21 ° C to allow the reaction product to leave the reactor with a maximum temperature of 49 ° C by the reaction film in a reflux of cold acid rapidly from about 77 ° C to preferably 32 to 38 ⁰ C was cooled. The sulfonated product was digested for 1 to 5 minutes and then fed to a cyclone in order to separate off the air which had diluted the SO2.

The product of the sulfonic acid reaction was fed to a neutralizer along with an excess of sodium hydroxide, based on the total amount of sulfonic acid and sultone in the sulfonic product. j | The neutralizer was maintained at a temperature of about 49 ° C. Immediately after leaving the neutralizer, the neutralized sulfonic acid was heated to a temperature of about 116 ° C. in a shell and tube heat exchanger, the temperature in the heat exchanger being maintained by means of superheated steam. The product, which had been heated to a temperature of approximately 116 ^° C., was then fed into a hydrolyzer which was operated at overpressure. Heat was added to the hydrolyzer only in the amount necessary to compensate for the heat loss occurring during hydrolysis, the heat of the neutralized sludge being sufficient to cause hydrolysis of the sultonah portion of the product. The hydrolysis was carried out in a tubular hydrolyzer for approximately 1/2 hour to avoid back mixing. After hydrolysis, sulfonic acid was added to the sludge to neutralize the excess sodium hydroxide and produce a final product with a pH of about 8. This product proved to be extremely suitable as a synthetic cleaning agent or laundry detergent. The analysis of the product gave the following values: Free oil 2.8 % (active basis)

Sodium Sulphate 0.8 % (active basis)

Bleached color according to Klett II5 (5 # solution).

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Example 2

The same olefin that was used in Example 1 was sulfonated as in Example 1 and neutralized in a neutralizer running on a Temperature of 116 ° C was maintained. Some of the products leaving the neutralizer were returned to the neutralizer, the return loop also being kept at a temperature of approximately 116 ^° C. A small recirculation loop was cooled to approximately 82 ° C before the system was adjusted to pH about 12, which controlled the amount of sodium hydroxide entering the neutralizer. Operating at a temperature of 116 C in the neutralizer and recycle loop, more than 90 % of the sultones present in the sulfonation product are decomposed in the neutralizer.

After neutralization, the product was passed into an isolated hydrolyzer which was kept at positive pressure was to prevent boiling. The product of hydrolysis was an end product which was more advantageous than synthetic Cleaning agents or detergents can be used. It it was again found that there was no problem of excessive sludge viscosity or gel formation, indicating that by means of the method according to the invention a sludge having a high solids content is treated without difficulty can be. The higher neutralization temperature yielded a product with a color with a slightly higher Klett value than in example 1.

Example 3

A sulfonation of sperm alcohol was carried out, which had the following composition:

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- 15 - Water content 0.47 % 1917300 Saponification number 1.58 Acid number 0.2 Hydroxyl number 207.6 Iodine number .69.1

The alcohol was sulfonated in a sulfonation plant with a film reactor operating with an air-SO-i mixture, a molar ratio of SO 1 to alcohol of 1.15 J 1 and a cooling water temperature of 21 ° C. being used. This allowed a quench cooling of the effluent from the reaction product surface at 32 ⁰ C in a rlickge leads en flow of cold acid. The neutralization temperature was 93 ° C g, where a neutralizer was used, as it is illustrated in Fig. 1 ,, but without the use of hydrolyzing. It was found that the neutralization of the sulfonated unsaturated alcohol at this temperature of 93 ° C. caused the decomposition of an unstable structure, and this decomposition was complete after a few minutes. No pH shift was observed after neutralization, indicating complete decomposition of the unstable structure * It was found desirable to cool the hydrolyzed product in order to prevent reconversion of the sulfonated alcohol. Accordingly , the hydrolyzed product was cooled to a temperature of about 27 to 54 ° C. The product had the following mensetzung together (:

Active ingredient 50 % oil 6 # (active base)

Sodium Sulphate 1 # (active base)

Unbleached color according to Klett 250 (5 # solution). As with the previous examples, there was no problem of excessive slurry viscosity or gelation on.

From the foregoing it can be seen that the method according to the invention is an improvement in sulfonation, neutral

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tion and hydrolysis of the sulfonation of G ^ -OIefinen and in the sulfonation and neutralization vcn un- 'representing saturated alcohols. Thus, it has in accordance with the ER - invention ¹ found possible the viscosity with excessive sludge and eliminate gel formation associated shortcomings which previously occurred in the neutralization and hydrolysis of such sulfonation by the neutralization at a temperature of 4 ^ to 5 ^ ° C and then a heat treatment is carried out at 88 to 15 ^ ⁰ C or by the neutralization at a temperature of 82

to 116 ⁰ C is executed. ; '\

The products obtained according to the invention are olefin sulfonates or sulfates Qf unsaturated alcohols, which are both useful as synthetic cleaning or detergent can be used. The materials produced according to the invention can be used either alone or in combination with other synthetic detergents and detergent formers in conventional detergent compositions.

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Claims (12)

Claims QJ. Process for the production of OC-olefin sulphonates which can be used for cleaning agents or detergents, which are obtained by sulphonation of 06-olefins and subsequent neutralization and hydrolysis, characterized in that the neutralization at a temperature of kj to 54 ° C is brought about in a stirred system prior to hydrolysis. 2. The method according to claim 1, characterized in that C ₁₂ -C ₂₀ - OC olefins are sulfonated. Yes J5. Method according to claim 1 or 2, characterized in that that the neutralization is carried out with an excess of the neutralizing agent and, after the hydrolysis, sulfonic acid is added to produce a final product having a pH in the range of 6-10. 4. The method according to any one of claims 1 to 3, characterized in that during the hydrolysis a supply of heat takes place only to such an extent that the heat loss occurring during the hydrolysis is compensated. Process for the production of (X-olefin sulfonates which can be used for cleaning or laundry detergents and which are obtained by sulfonation of (X-olefins and subsequent neutralization and hydrolysis), characterized in that to ( enable the use of a higher solids content, the neutralization at a Temperature of 82 to 116 ° C is brought about, followed by an additional hydrolysis in an external hydrolyzer. 6. The method according to claim 5 »characterized in that C ₁₂ -Cp ₀ - CX-olefins are sulfonated. 7. The method according to claim 5 or 6, characterized in that that the neutralization with an excess of the neutralizing agent carried out and after hydrolysis sulfonic acid is added to an end product with a pH in the range from 6 to 10. 909845/1688 8. The method according to any one of claims 5 to 7, characterized characterized in that, during the hydrolysis, heat is supplied only to such an extent that the heat loss occurring during the hydrolysis is compensated. 9 · Process for sulfonating Oi -olefins, characterized in that a 0 (-olefin with sulfur trioxide and air at a molar ratio of SCU to (X-olefin in the range from 1.10 to 1.25 ι 1 and a temperature is sulfonated from about 32 ° to about 49 ° C, the sulfonation product is digested for a period of "about 1 to 5 minutes, the digestion product with a caustic agent at a molar ratio of the caustic agent to SO., from 1.02 to 1, 05: 1 is neutralized and the neutralized product is hydrolyzed. 10. The method according to claim 9> characterized in that the neutralization is carried out at a temperature of 4> to 5 ² I- ⁰ C, which is followed by heating to a temperature of 88 to 154 ⁰ C before the hydrolysis. 11. The method according to claim 9 or 10, characterized in that C-Jp-Cp ₀ - 'OC-Qlefins are sulfonated. 12. The method according to claim 9 j, characterized in that that the hydrolysis takes place at a temperature of 82 to 116 ° C is carried out. 1J>. Process according to Claim 12, characterized in that C ₁₂ -Cp ₀ - OC-01efins are sulfonated. left Process for sulfonating unsaturated alcohols, characterized in that the unsaturated alcohol at a temperature of 32 to 43 ° C with sulfur trioxide and Air with a molar ratio of SO- to alcohol of 1.10 sulfonated to 1.8: 1 and the sulfonation product with excess caustic is neutralized at a temperature of 93 to 10f> ° C. 909845/1688