JPH0430940B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an olefin sulfonate by neutralizing and hydrolyzing a sulfonation reaction product of olefin with a basic solution, and in particular, a method for continuously neutralizing and hydrolyzing a sulfonation reaction product of α-olefin. The present invention relates to a method for feeding a sulfonation reaction product of α-olefin in the case of decomposition to produce α-olefin-sulfonic acid and a basic solution during startup. In general, when manufacturing chemical products, water is often required during the manufacturing process, but even in this case, when considering the operability and economic efficiency of the work process when further processing the chemical product, It is desirable that the moisture content be as low as possible. The same is true for α-olefin sulfonate (AOS salt); the sulfonation reaction product of α-olefin can be produced in an anhydrous system, but in order to make it into a water-soluble surfactant that is easy to use, Neutralization and hydrolysis must take place, with water necessarily being introduced into the reaction system. Neutralization and hydrolysis operations are easy if a large amount of water is introduced, but it is necessary to introduce as little water as possible.
For example, if the concentration is to be less than 25 to 30% by weight, it is necessary to use a highly concentrated basic solution as an alkaline agent.Especially when this is done continuously, due to its strong salting-out effect, However, there was a problem in that the produced neutralized product coagulated and solidified and adhered to the inner walls of the piping in the reactor, making operation difficult. A method for obtaining a highly concentrated α-olefin sulfonic acid neutralized product by avoiding such a strong salting-out effect at the start of neutralization is disclosed in JP-A-58-167558.
A method via partial neutralization of the sulfonation reaction product is disclosed in No. However, this method cannot be said to be a completely satisfactory process in that there is a possibility that the slurry at the initial stage of neutralization may become slightly acidic, which may lead to corrosion of the equipment. On the other hand, there is a method disclosed in JP-A-58-157758 in which PEG and aromatic carboxylic acid are added during neutralization, but this method results in the presence of an impurity called a viscosity reducing agent in the neutralized product of olefin sulfonic acid. , which may be undesirable depending on the intended use of the product. The present invention was made to solve this problem, and the sulfonation reaction product of an olefin having 10 to 20 carbon atoms and a basic solution are continuously supplied to a mixing zone to neutralize the sulfonation reaction product. At the same time, a part of the neutralized product is recycled to the mixing zone to produce a neutralized olefin sulfonic acid, and when the supply of the sulfonated reaction product and the basic solution is started, the generated Surfactant concentration in neutralized product is 40~
The sulfonation reaction product and the basic solution are supplied and neutralized so that the amount of unreacted base remaining is 2 to 10% by weight of the amount of the surfactant. Concentration 65 characterized by supplying and neutralizing the sulfonation reaction product and the basic substance so that the surfactant concentration in the neutralized product is 65% by weight or more after being circulated to the mixing zone. The gist of the present invention is a continuous process for producing a high concentration neutralized olefin sulfonic acid product of more than % by weight, and has succeeded in obtaining the desired effects. The sulfonation reaction product of an olefin with a carbon number of 10 to 20 is obtained by sulfonating a C _{10 to 20} olefin produced by the Ziegler method, wax cracking method, etc. with a sulfonating agent such as sulfur trioxide in a conventional manner. It can be obtained by This sulfonation reaction product contains olefin sulfonic acid (R′CH=
CHSO ₃ H, R″CH=CHCH ₂ SO ₃ H,...) and alkyl sultone (

【formula】

[Formula]...) is included. Basic solutions include NaOH, KOH, Mg(OH)
An aqueous solution or dispersion of ₂ , Ca(OH) ₂ , or a lower alcohol solution or dispersion can be used, but NaOH or KOH aqueous solutions are most commonly used. Furthermore, alkanolamines, ammonia, liquid ammonia, etc. can also be used. The concentration and amount of the basic solution used are determined under the conditions described above, i.e., from the start of neutralization until the produced neutralized product circulates through a continuous neutralization loop, the concentration and amount of the basic solution are determined by the surfactant (hereinafter abbreviated as AI) in the produced neutralized product. The concentration is 40-60% by weight, and the residual unreacted basic substance (hereinafter abbreviated as FA) is 2% compared to AI.
It must be determined appropriately depending on the type of sulfonation reaction product and basic substance so that the AI is ~10% by weight and after the neutralized product is circulated, the AI is 65% by weight or more. Of course. It is desirable that as little free basic substances remain as possible in the neutralized slurry when AI is 65% by weight or more, and usually 1% by weight based on AI.
It is preferable to adjust the amount of the sulfonation reaction product, the basic solution, and if necessary, the amount of water supplied so as to be as follows. This is because, when the AI is 65% by weight or more, the presence of an excess basic substance not only tends to cause the AI to coagulate and solidify due to the salting-out effect described above, but also tends to increase the viscosity. On the other hand, in a neutralized product of AI40 to 60% by weight, the viscosity increases outside the FA concentration range stated in the claims,
This is not preferable because it causes a decrease in fluidity, a decrease in operability, and a deterioration in quality. Regarding other operating conditions such as neutralization temperature, residence time, equipment, etc., please refer to the patent application.
It is desirable to comply with No. 58-247998. However, there are no particular restrictions on the means for changing the supply conditions of each raw material at the start of neutralization to the supply conditions of each raw material after the produced neutralized product circulates within the neutralization loop and until normal operation is switched. As mentioned above, AI40~60% by weight, FA2~
By starting the neutralization at 10% by weight, the strong salting-out effect of basic solutions can be avoided and gelation can also be prevented. Moreover, after changing the concentration of the olefin sulfonation reaction product, the basic solution concentration, and the feed amount to obtain a highly concentrated olefin sulfonate slurry with an AI of 65% by weight or more.
Significant gelation or thickening can be avoided even in an unsteady state where AI and FA are constantly changing. After the neutralization system has been completely replaced with a slurry containing AI65% by weight or more, there will be a slurry in which sultone hydrolysis has progressed considerably or neutralization has progressed considerably, so the olefin sulfone Even if the reaction product is fed with a highly concentrated basic solution corresponding to the neutralization equivalent, the salting-out effect can be avoided and solidification of the neutralized product will not occur. The sulfonic acid neutralized product of olefin thus obtained is then heated to a high temperature of about 150° C. or higher, and the sultone in the sulfonic acid is almost completely hydrolyzed and annihilated to form an olefin sulfonate. FIG. 1 is a flow diagram of raw materials and products used in Examples of the present invention. First, upon startup, the sulfonation reaction product of olefin and the basic substance are transferred from the feed pump 1 and the feed pump 2 to the mixing device (mixing zone) 3 with AI40 to 60% by weight and FA2 to 10% by weight.
Added continuously at a feed rate of weight % to AI. This mixture is transferred to the recycling system 7 by the transfer pump 4.
The sulfonation reaction product of α-olefin is neutralized in the mixing device 3 and the recycling system, and the sultone is further decomposed. After this neutralized product is recirculated from the recycling system 7 into the mixing device 3, the amount of basic solution supplied from the feed pump 2 to the mixing device 3 or its concentration is increased to 65% by weight or more, with FA being 1 for AI. A neutralization reaction is caused by changing the adjustment so that it is less than % by weight, and part of it is circulated to the recycling system 7, and the remaining part is sent to the hydrolyzer 5.
After that, the slurry is taken out from the slurry outlet 6. In addition,
11 and 12 represent a neutralization system and a hydrolysis system, respectively. According to the present invention, when neutralizing the sulfonation reaction product of α-olefin, the neutralization can be started safely while avoiding acidic hydrolysis and the salting-out effect caused by a highly concentrated basic solution, and in the process of transitioning to a steady state. No significant gelation or thickening was observed. Furthermore, no viscosity reducing agent is required. Therefore, the resulting highly concentrated AOS salt has a wide range of uses because it does not contain impurities such as viscosity reducing agents, and can also reduce manufacturing costs.Furthermore, there is no fear of corrosion because the neutralized product does not have an acidic region. do not have. Example 1 α-olefin (average molecular weight 229) containing 15% by weight of C ₁₄ , 50% by weight of C ₁₆ , and 35% by weight of C ₁₈ was prepared using a thin film sulfonation reactor to convert olefin to SO ₃
Sulfonated with dilute SO ₃ under conditions of molar ratio 1.05,
Sulfonation reaction product of α-olefin (hereinafter referred to as
(abbreviated as AOS). The conversion rate of α-olefin in this reaction was 96% by weight. Next, in the continuous neutralization hydrolysis apparatus shown in Figure 1, the feed speed of AOS feed pump 1 is
Adjust the feed rate to 55.0Kg/hr, and connect a 24.2% by weight NaOH aqueous solution to the alkaline agent feed pump 2, adjust the stroke of the pump so that the feed rate is 47.8Kg/hr, and start neutralization. preparations have been completed. To start neutralization, first turn on both feed pumps 1 and 2 at the same time and turn on the AOS,
NaOH feed was started. Soon after, the mixing device 3 and transfer pump 4 (pump capacity 700/
hr) was also made movable. Neutralization system (capacity 20
) until the neutralized slurry fills AOS, 24.2
Continue to feed wt% NaOH aqueous solution. When a part of the slurry was sampled from the neutralization system and its properties and viscosity were measured, the following values were obtained. AI 55% by weight FA 6% by weight vs. AI (as NaOH) Viscosity 60 poise (measured at 80°C) [A Bruckfried type viscometer (vismetron VSH model, Seiki Kogyo Research Institute) was used as the viscometer.
The same applies hereafter] Next, set only the alkaline feed pump (2) to 31.7
Switching to the wt% NaOH aqueous solution, without changing the feed on the AOS side, the stroke was changed so that the feed rate became 25.8 Kg/hr, which took several seconds, and feeding of both solutions was continued. 10Kg/cm ² in the jacket of hydrolysis system 12 (capacity 40)
(G) While starting the steam feed,
A portion of the slurry was extracted from the slurry outlet 6 to adjust the pressure within the neutralization system so that the pressure within the neutralization system did not exceed 5 kg/cm ² (G). At the same time, take appropriate samples from the extracted slurry,
We continued to observe changes in AI, FA, and viscosity. The results are shown below.

[Table] After 30 minutes, the properties were almost constant. Operation continued in this state for about two hours, but the system remained stable and no trouble was observed. The color tone of the 10% by weight aqueous solution of sodium α-olefin sulfonate slurry obtained in this manner was determined by KLETT-SUMMERSON of KLETT MEG.
When measured with Photoelectric Colorimeter model 900-3, the color tone was 115, which was good, and the odor was also satisfactory. After the experiment was completed, the mixing equipment, neutralization system piping, etc. were disassembled and the corrosion conditions inside them were observed, but no evidence or signs of corrosion were observed. Comparative Example 1 Using the same apparatus and the same AOS as in Example 1, and performing the same operations as in Example 1, various experiments shown in Table 1 were conducted. The results are also shown in Table 1.

[Table] Comparative Example 2 α-olefin (average molecular weight = 196) containing 2% by weight of C ₁₂ and 98% by weight of C ₁₄ was sulfonated in the same manner as in Example 1 to obtain AOS. Next, in the continuous neutralization and hydrolysis apparatus shown in Figure 1, the AOS feed rate of AOS feed pump 1 was adjusted to 55.0 Kg/hr, while the alkali agent feed pump 2 was fed 48% by weight.
Connect NaOH aqueous solution and its feed rate is 17.4
Preparation for neutralization was completed by adjusting the stroke of the pump so that the amount was Kg/hr. To start neutralization, first, both feed pumps 1 and 2 were turned on at the same time, but after a few seconds, the feed pressure of both pumps increased, and the feed of AOS and 48 wt% NaOH aqueous solution was no longer available. Summer. Then, when the pump was turned off and the neutralization device was disassembled and examined, it was found that the mixing device 3 was clogged with a solid mass of neutralization reaction product. This current material adhered to the inner wall of the mixing device and was difficult to remove even when heated with steam. In this way, when a neutralized product with a water content of 25 to 30% by weight or less in the slurry produced is directly produced, it is subjected to a strong salting-out effect due to the highly concentrated basic solution. Example 2 Using the same AOS and the same equipment as in Comparative Example 2, and using KOH as an alkali agent, various experiments shown in Table 2 were conducted in the same manner as in Example 1. The results are also shown in Table 2.

[Table] Even in the unsteady state when changing the concentration of the KOH aqueous solution and the feed amount, no extreme increase in viscosity or gelation was observed, and the production of AI75% by weight slurry could be stably made. Thus, by following the present invention, a highly concentrated aqueous potassium α-olefin sulfonate slurry having an AI content of 75% by weight can be obtained. Example 3 A sulfonation reaction product derived from 1-dodecene (molecular weight = 168) was subjected to a neutralization experiment in the same manner as in Example 1 under the conditions shown in Table 3. The results are also shown in Table 3.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a flow diagram of raw materials and products used in Examples of the present invention. 1, 2...Feed pump, 3...Mixing device,
4...transfer pump, 5...hydrolyzer, 7...recycling system, 11...neutralization system, 12...hydrolysis system.

Claims (1)

[Claims] 1. Continuously supplying a sulfonation reaction product of an olefin having 10 to 20 carbon atoms and a basic solution to a mixing zone to neutralize the sulfonation reaction product,
When circulating a portion of this neutralized product to the mixing zone to produce a neutralized olefin sulfonic acid,
When the supply of the sulfonation reaction product and the basic solution is started, the concentration of surfactant in the neutralized product is 40 to 60% by weight, and the amount of remaining unreacted base is 2 to 2% of the amount of surfactant. After feeding and neutralizing the sulfonation reaction product and the basic solution to a concentration of 10% by weight, and circulating the neutralized product to the mixing zone,
A concentration characterized by supplying and neutralizing the sulfonation reaction product and the basic substance so that the surfactant concentration in the neutralized product is 65% by weight or more.
A method for producing a continuous high concentration olefin sulfonic acid neutralized product of 65% by weight or more.