JPH01319491A - Production of powdery fatty ester of sucrose - Google Patents

Abstract

PURPOSE:To obtain the subject compound suitable as a surfactant, etc., with industrial advantage by adding an acidic water to a reaction mixture containing a fatty ester of sucrose prepared by the aqueous-solvent method, dissolving the precipitated cake, separating salts using an ultrafiltration membrane, slurrying the resultant solution using a reverse osmosis membrane and carrying out spray drying the slurry. CONSTITUTION:An acidic water is added to a fatty ester of sucrose-containing reaction mixture prepared by the aqueous-solvent method containing unreacted sucrose and methyl ester of a fatty acid, a catalyst, soap, fatty acid, etc., to dissolve the precipitated cake in water and the resultant solution is contacted with an ultrafiltration membrane to permeate and separate two substances, i.e., unreacted sucrose and a salt produced from the catalyst through the membrane together with water. The residual aqueous solution containing four substances of a fatty ester of sucrose, an unreacted methyl ester of fatty acid, soap and fatty acid is contacted with a reverse osmosis membrane to be slurried and subjected to spray drying, thus obtaining the objective powdery fatty ester of sucrose.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for producing powdered sucrose fatty acid ester, and more particularly to a method for producing powdered sucrose fatty acid ester industrially using only water without using any solvent.

[Conventional technology]

(Background) Currently, sugar fatty acid esters useful as surfactants are produced industrially by combining sucrose and C8-C22 higher fatty acid methyl esters in a solvent (dimethylformamide, dimethyl sulfoxide, etc.) under an appropriate catalyst. After reacting (solvent method: Japanese Patent Publication No. 35-13102) or using water without using a solvent, sucrose and fatty acid stone are made into a molten mixture,
It is obtained by reacting it with higher fatty acid methyl ester in the presence of a catalyst (water medium method: Japanese Patent Publication No. 14465/1983). However, in both of these two synthesis methods, in addition to the target sucrose fatty acid ester, the reaction mixture contains unreacted sugar, unreacted fatty acid methyl ester, residual catalyst, soap, free fatty acid, Contains impurities such as volatile matter, and among these impurities, impurities whose content exceeds the specified amount must be removed before becoming a product.In particular, among the above impurities, unreacted sugars must be removed. Removal of this is of utmost importance due to its large amount. (Problems with the prior art) By the way, as a means of removing unreacted sugar from a reaction mixture of sucrose fatty acid ester, one method is to remove unreacted sugar from a reaction mixture of sucrose fatty acid ester by taking advantage of the fact that ordinary solvents have almost no ability to dissolve sucrose. Conventionally, a method has been commonly used in which a solvent is added to the solution and contaminating unreacted sugars are removed as a precipitate. but,
Regardless of the small scale, in factories involved in the production of sucrose fatty acid esters using industrial plugs, the inconvenience of handling solvents, such as the trouble of recovering solvents, the risk of fire, and occupational health issues for workers, is a problem. There are things that stand out. However, since there are no other effective means, solvents are still used to remove unreacted sugars. As specified, solvents such as ethyl acetate are effective for purification including removal of unreacted sugars. For reference, the disadvantages associated with handling solvents are listed below. ■ Risk of explosion or fire. ■ Explosion-proofing of electrical equipment in preparation for ■ above. ■ The manufacturing equipment is sealed in preparation for the above ■. ■ The entire building will be made into a fire-resistant structure in preparation for ■ above. ■ Increase in fixed costs due to ■, ■, and ■ above. ■ Increased cost due to solvent wastage. ■ Negative effect of residual solvent remaining in the product sucrose fatty acid ester. ■ Negative impact on employees' health, which in turn increases costs due to increased man-hours.

[Problem to be solved by the invention]

Under these circumstances, conventionally, without solvent, ie. The present invention seeks to solve the long-awaited development of a technology that can synthesize and purify sucrose fatty acid ester without using any solvent other than water during synthesis and purification. The challenge is to establish a technology for producing sucrose fatty acid esters without using any solvents.

[Means to solve the problem]

(Required by JI) In order to solve the above problems, 1. The method for producing powdered sucrose fatty acid ester according to the present invention consists of unreacted sugar, unreacted fatty acid methyl ester synthesized by a water medium method,
A sucrose fatty acid ester-containing reaction mixture containing a catalyst, soap, fatty acids, etc. is heated to an acidic pH range by adding acidic water, separating the precipitated cake, and dissolving it in water. The aqueous solution was brought into contact with the ultrasonic membrane under pressure to remove any unreacted material. i. Two groups of salts produced from the catalyst are separated together with water by passing through the membrane to form an aqueous solution containing the remaining sucrose fatty acid ester, unreacted fatty acid methyl ester, soap, and fatty acid. The aqueous solution is brought into contact with a reverse osmosis membrane under pressure, or if necessary, the aqueous solution is evaporated and concentrated to form a slurry of an appropriate concentration, followed by spray drying. The principles of the invention, implementation conditions, and other details of the invention will be described below. (a. Precipitation of sucrose fatty acid ester with acidic water) p
H-3,0~5.5, tI8 at a temperature of about 10℃~40℃
I adjustment. Use temperature-controlled acidic water, ftl! SE is precipitated by adding 4 fatty acid esters to the reaction mixture. The mixture becomes cake-like, and impurities such as unreacted SiM sugar become dissolved. The acids used here are, for example, mineral acids such as hydrochloric acid and butyric acid, and organic acids such as acetic acid and lactic acid, but are not limited to those listed separately. In this way, impurities can be removed from the cake side. When the temperature of the acidic water exceeds 40°C during the precipitation of SH, if the operation is carried out for a long time, for example, over several months, there is a concern that not only SE will be decomposed by the acid, but also the viscosity will increase. Operation becomes difficult. On the other hand, maintaining a low temperature of 10° C. or less requires a refrigerator that is not economical. Therefore, it is usually preferable to operate at 10°C to 40°C, particularly around room temperature. In addition, when precipitating SH with this acidic water, it is necessary to remove from the SE cake as much as possible the unreacted sugar remaining in the SE cake and the salt by-produced by neutralization of the catalyst. It is desirable that the SE cake is shredded in the acidic water to the smallest possible particle size. This can be efficiently achieved by fragmentation using a homogenizer or a colloid mill (for example, Mycolloider), and unreacted loquat and two salt groups derived from the catalyst are transferred from the precipitate [SE cake] into the acidic aqueous phase.
However, although it is said to be a substantially small amount, it is inevitable that some SE will elute into the acidic aqueous phase. Therefore, it can be effectively suppressed by relatively increasing the diester or triester content. After the above precipitation of SH with acidic water, it is filtered and the pt+ of the SE cake is returned to neutrality, water is added to prepare an aqueous solution of SE, and the process proceeds to the next ultrafailure. (b Ultracarcinogenesis) (b-1 Principle) It is known (applicant Published by the company (sugar ester i6>>
(page 102). By the way, sucrose fatty acid ester contains 8 of the sucrose molecule.
As is well known, there are types such as monoesters, diesters, and triesters in which one to three 08-C22 fatty acid residues are bonded to any of the oxygen atoms of the hydroxyl groups.
Monoesters have a greater affinity for sucrose fatty acid esters than diesters and triesters, but their degree of micelle formation in water is small. Form. On the other hand, diesters and triesters have relatively low phyllophilicity but have extremely high micelle-forming ability, so they form sucrose fatty acid ester micelle aggregates with extremely large molecular weights (i.e., large molecular diameters) in water. do. Commercially available sucrose fatty acid esters are manufactured as a single monoester, and the monoester content is usually
For example, it is manufactured as a mixed composition of 70%, 50%, 30%, etc. As a result of repeated research to solve the above-mentioned problem, the inventors discovered that 1 For example, sucrose fatty acid ester with a high monoester content of 70% is different from sucrose fatty acid ester with a low monoester content of 50%. Since it creates a sucrose fatty acid ester aggregate with a lower molecular weight than that of the monoester-containing Q50, the microscopic diameter of the aggregate is correspondingly smaller. % of sucrose fatty acid esters, and therefore pass through the membrane along with unreacted sugars and by-product salts from the catalyst (formed when the catalyst is neutralized with acid). I learned that it has an undesirable tendency to be easy to use. Therefore, as a countermeasure for this problem, the present inventors have found that when it is desired to remove impure seams with a high monoester content, unreacted sugars from sugar fatty acid esters, salts derived from catalysts, etc., a method with a small molecular weight cut-off (i.e.,
(small pore size) il! It is better to select a membrane with a high molecular weight cutoff (that is, a large pore size) in the case of a sucrose fatty acid ester with a low monoester content.
11! It has been found that it is advantageous to select a membrane with a diaphragm in order to speed up the processing speed. In addition, the inventors found that among the substances contained in the reaction mixture, unreacted fatty acid methyl ester, soap, and the king of fatty acids exist in a state encapsulated in a micelle structure aggregate of sucrose fatty acid ester. Therefore, it has been confirmed from many experimental results that it is virtually impossible to separate sucrose fatty acid esters and their champions by filtration. Thus, the conclusion derived from many experiments was that the impurities that can pass through a filtration membrane (with an appropriate molecular weight cutoff) together with water using pressure as a driving source are two groups: unreacted sugar and salt derived from the catalyst. On the other hand, substances that are incorporated into the high molecular weight micelle aggregates and cannot pass through the filtration membrane include sucrose fatty acid esters, unreacted fatty acid methyl esters, soaps, and free fatty acids. The present inventor cleverly utilized these facts and selected a filtration membrane with an appropriate molecular weight cutoff to convert unreacted spears and catalyst-derived salts into sucrose fatty acid ester and unreacted fatty acid methyl. It has been successfully used to separate and remove esters, soaps and fatty acids. <<b-2i! ! (Molecular weight of the target substance) In order to select an ultrafiltration membrane with an appropriate molecular weight cutoff, it is necessary to know the approximate molecular weight of the target substance.The molecular weights of these single substances related to the invention are as follows: It is as follows. O Sucrose; 342 0 Unreacted fatty acid methyl ester Stearic acid methyl ester = 230 0 When using hydrochloric acid generated by neutralization of the catalyst (KzCOi) → Potassium lactate = 128 When using acetic acid → Potassium acetate = 98 0 Sucrose Sugar fatty acid ester (as a monomer that does not form micelle aggregates) Sucrose monostearate = 600 Sucrose distearate = 658 Sucrose distearate = 1118 Other fatty acid esters such as myristate, palmitate, arachinate, behenate, etc. There is no big difference in molecular weight. O Sodium stearate = 298 Potassium stearate = 314 0 Fatty acid stearic acid = 276 0 Water = 18 By the way, the apparent molecular weight of the micelle structure aggregate of sucrose fatty acid ester is The molecular weight (referred to as molecular weight) can be experimentally assumed as follows. Since sucrose fatty acid ester in an actual aqueous solution forms a micelle aggregate in water, for example, when the number of micelles of sucrose fatty acid ester is 10, the molecular weight of the micelle aggregate is monoester Assuming 100%, ◇Molecular i of monoester monomer (800)XIO=8
,000 Assuming 100% diester, ◇Molecular weight of diester monomer (650)! 10-8,5
Assuming 80 triester is 100%, ◇Molecular weight of triester (1,116)XIO-11,
It becomes 160. Since the actual sucrose fatty acid ester is a mixture of monoester, diester, and triester, the molecular weight of the micelle aggregate of the sucrose fatty acid ester may be defined as its monouniform molecular weight. (B-3 Molecular weight cutoff of cancer membrane) A membrane suitable for the purpose of the invention is selected as follows. First, with an ultrafiltration membrane with a molecular weight cutoff of 200, even if the reaction mixture in the aqueous solution state is supplied to one membrane under pressure to remove unreacted sugars and salts generated from the catalyst (K2CO2), the What can be separated by a filtration membrane are water, catalyst (K2C
O3). Sucrose with a molecular weight of 342, which is larger than the molecular weight cutoff of 200, is
Since it does not pass through the filtration membrane at all, unreacted sugar is released! JA
Cannot be separated or removed from fatty acid ester. Next, in the case of a filtration membrane with a molecular weight cutoff of 5,000, sucrose and salt from the catalyst can easily pass through the pores of the filtration membrane since their respective molecular weights are smaller than 5,000. The sucrose fatty acid ester constitutes the above-mentioned micelle aggregate, and assuming that the number of micelles is, for example, 100 g, the molecular weight of the sucrose fatty acid ester micelle aggregate is estimated to be e,ooo or more. Therefore, the molecular weight cutoff of the filtration membrane is 5,00
If it is larger than 0, it is assumed that the micelle aggregate does not pass through the micropores, but this assumption has been experimentally confirmed. Finally, we also investigated the case of a filtration membrane with a molecular weight cut-off of 1,000, and the results were as expected. In this way, by appropriately selecting the molecular weight cutoff of the ultrafiltration membrane, impurities including unreacted sugars in the sucrose fatty acid ester reaction mixture can be efficiently removed. (b-4 Conditions that the filtration membrane should have) The unreacted sugar contained in the sucrose fatty acid ester reaction mixture and the king of the salts by-produced from the catalyst (K2 CCh) are mixed with sucrose fatty acid ester, stone powder, and unreacted sugar. When attempting to separate from fatty acid methyl ester and fatty acid, the filtration membrane must have the following conditions: - If the membrane has an appropriate molecular weight cutoff, it must be resistant to external physical forces. . ■ Must be heat resistant and not decomposed by microorganisms. ■ Appropriate molecular weight cutoff and large processing capacity. ■ Long service life. ■ Must be available at an economical price. etc. Since there has been remarkable progress in technology in the production of ultrafiltration membranes in recent years, there are commercially available membranes that meet the above conditions as described below. (B-5 Actual Limitations) The composition of the reaction mixture suitable for carrying out the present invention is as follows: 15% to 95% sucrose fatty acid ester and 1% to 1% unreacted sugar.
80%, unreacted fatty acid methyl ester 0.5%~10
%, catalyst (K2CCI3) from 0.05% to 7%, soap from 2% to 60%, and fatty acid from 0.5 to 10%. When trying to remove unreacted sugars, catalyst (K2CO2) and the king of salts generated from acid neutralization from a reaction mixture with this composition by ultrafiltration, fatty acid methyl esters in the reaction mixture are Number CI6~(d
The sucrose fatty acid ester of No. 2 and derived therefrom is preferably a feed. Potassium carbonate (K2CO2) is typically used as a catalyst for the synthesis of sealant sugar fatty acid esters, but catalysts used in general flucolysis reactions, such as sodium carbonate and sodium alkoxide, can also be used. The type of fatty acid may correspond to the above-mentioned fatty acid methyl ester. When carrying out the present invention, acidic water is added to the sucrose fatty acid ester reaction mixture to be synthesized by the aqueous medium method so that water: reaction mixture = 5:1 to 4o: 1 (ffi ratio). More preferably, water:reaction mixture=20:1
1ffi ratio) and dissolve. Sucrose fatty acid esters are easily hydrolyzed in alkaline conditions, so to prevent hydrolysis, add acidic water as soon as possible to adjust the pH of the solution to 3.0 to 5.5, preferably pl+.
Adjust yJ to around 3.5. At this time, the acid used is
Organic acids such as lactic acid and acetic acid and inorganic acids such as hydrochloric acid and sulfuric acid are used. In this way, a portion of the sucrose fatty acid ester will dissolve, but a large proportion of the SE will precipitate. Add water to the precipitate cake, heat if necessary to obtain SE in a dissolved state, and then heat at 50°C.
The inventors have found that maximum filtration rates are obtained when the temperature is particularly within the temperature range of 40-60°C. Ta. That is, by adjusting the mixing temperature to 40 to 60°C, optimally around 50°C, the king of salts from unreacted sugar and catalyst (K2Cox) can be used in the most efficient manner along with water, for the reasons explained later. Passes through the filtration membrane well. The reason for this is 40
At ~60°C, the molecules of the micelle aggregates of sucrose fatty acid ester become gigantic, resulting in a decrease in the total number of micelle aggregates. This is presumed to be due to the fact that substances that are not originally involved in the formation of micelle aggregates, such as unreacted sugars, are less likely to resist the sucrose fatty acid ester, making it easier for unreacted sugars to pass through. . As is known, sucrose fatty acid ester aqueous solution generally has a concentration of 40
The maximum viscosity is between ~60°C (cited above, p. +03), which suggests that it can have the maximum molecular weight within that temperature range;
This can explain the reason why unreacted sugars etc. show the maximum passing rate in the temperature range of ℃. Thus, the aqueous reaction mixture solution containing sucrose fatty acid ester maintained at 40-60°C was pumped to 1-20°C.
Pressure is increased to Kg/C112G as a driving source, and the membrane is brought into contact with the membrane in the hydrogen ion concentration range of PH6.2 to 8.2. As a filtration membrane, a cellulose-based membrane is not only physically weak but also easily attacked by microorganisms, so it is not very desirable for practical purposes. Practically preferred are membranes made of polysulfone or polyvinylidene fluoride reinforced with a support layer. Both of these types of filtration membranes are currently commercially available, and have excellent heat, acid, and alkali resistance, are resistant to external physical forces, and do not allow microorganisms to grow on the membrane surface. As mentioned above, i! ! When determining the molecular weight cutoff of the membrane, it is important to select a membrane that can efficiently separate unreacted ears without leaking sucrose fatty acid ester and has a large overrate. 8 As a result of study, the inventors found that they had developed a membrane fractionator that satisfies the desired conditions: no leakage of sucrose fatty acid ester, no loss of separation of unreacted sugars and by-product salts, and high filtration rate. As molecular weight,
A value in the range of 1.000 to 1.000 is preferable, and in particular, 1.
It has been discovered that a filtration membrane with a molecular weight cutoff of 5,000 is most preferable. A membrane with a molecular weight cut-off of more than 5,000 causes leakage of sucrose fatty acid ester, albeit slightly, while a membrane with a molecular weight cut-off of less than 5,000 reduces the filtration rate. However, in either case, it does not bring about such a disadvantage that it is not industrially profitable. Among the ultrafiltration membranes currently on the market, those suitable for the purpose of the invention include, for example, the ultrafiltration membrane sold by Toshi Engineering ■ under the trade name (TERP-E-5>> (polyvinylidene fluoride)). , <(TERP-)IF-10) (
borisulfone type) and <<TERP-HF-100>>
(polysulfone type), etc. According to the above filtration membrane <(TERP-HF-10>> (ultrafiltration membrane with molecular weight cutoff = 10.000), the aqueous solution of the ci:l sugar fatty acid ester reaction mixture (p)I-7,5)
If the composition of the aqueous solution is as shown in Table 1 below, the temperature is 50°C,
When the driving pressure was increased to 5.0 Kg/cm'G, the separation rate of unreacted sugar reached 5.0 Kg/h with an ultrafiltration membrane (per unit) of effective surface a8rn'. . This is an industrially sufficient separation rate. Moreover, the rate of separation of the salt by-product from the catalyst was also sufficient. Incidentally, since the removal rate of unreacted sugars and salts from the catalyst can be sufficiently increased by adjusting the number of times the liquid passes through the filtration membrane, the water membrane is extremely advantageous for industrialization. (Left below) Table 1 (Composition of reaction mixture and its aqueous solution) Sucrose fatty acid ester (stearate) 47.0kg Water reaction Sucrose 47.0 Catalyst (K, C: 03
) 0.5 Unreacted fatty acid methyl (stearate) 1.56 (potassium stearate) 3.0 Fatty acid (stearic acid) 1.0 Subtotal 100.0 kg Water 2,00
0.0kg aqueous solution 2,1
00.0kg In this way, by using an ultrafiltration membrane, unreacted sugar and by-product salt from the catalyst (K2 C03) can be easily and industrially removed from the sucrose-fatty ester reaction mixture at once. and can be removed together with water, thus
Using only water and no solvent, unreacted sugar and catalyst (K
The objective of removing by-product salts from 2O(h) is achieved. (C reverse osmosis) The residual liquid (sucrose fatty acid ester, unreacted Aqueous solution containing a mixture of fatty acid methyl ester, hexagonal and fatty acid)
The composition is approximately 1% to 4% solid and 99% to 98% water.
Therefore, if left as is, it will be powdery. It is clear that the energy cost for dehydration to obtain the i-fatty acid ester is excessive. However, as a result of research, the present inventors have found that the use of reverse osmosis membranes enables extremely low-cost dehydration and AM, and that the above-mentioned problems can be solved industrially. The conditions that the reverse osmosis membrane used here must meet are: (1) It must be able to permeate only water from the aqueous solution after ultrafiltration. ■ It must not deteriorate due to the growth of bacteria, and ■ It must be heat and alkali resistant. ■ It has excellent water removal ability; ■ It has a long service life. As a result of our research, the present inventors have found that, in particular, a membrane made of polyether is reinforced with a support made of polysulfone.
It has been found that a reverse osmosis membrane made of a rt composite membrane and having a molecular weight cut off of 60 is suitable. A commercially available product suitable for this purpose is, for example, PEC100O sold by Toshi Engineering Co., Ltd. The above reverse osmosis membrane is preheated to a temperature of 40°C to 60°C, p) 18
．． When the aqueous solution to be treated, which is adjusted within the range of 2 to 8.2, is brought into contact under pressure, effective dehydration can be carried out. At this time, if the pH is less than 8.1, sucrose fatty acid ester precipitates and blocks the pores of the reverse osmosis membrane, making it impossible for only water to pass through the pores. Conversely, if the pH exceeds 8.3, fatal hydrolysis of sucrose fatty acid esters will occur, so it should not be made more alkaline than this.Furthermore, if the temperature drops below 40, water molecules will undergo reverse osmosis. The rate of passage through the pores of the membrane decreases rapidly. On the other hand, if the temperature exceeds 80°C, there is a concern that the sucrose fatty acid ester will be hydrolyzed, especially when subjected to long-term reverse osmosis, so this should also be avoided. It should be noted that these optimum operating conditions of 40° C. to 60° C. were also found by the present inventors, similar to the above-mentioned ultrasonic supertemperature. The pressure as a driving source is industrially preferably 50 kg.
/cm7G ~65kg/cm;'G. Under these conditions, the approximate water removal rate is 0 per m' of reverse osmosis membrane.
．． 06~O, Bkg water/min, which is a large value on an industrial scale. Under the above preferred conditions, the aqueous solution containing the above-mentioned troublesome mixture is dehydrated to have a water content of 60-98% and a solid content of
It is concentrated to 40-4%. If necessary, by using a concentration method other than the reverse osmosis membrane, such as evaporation Cm method under vacuum, it is possible to concentrate to a higher concentration than the above value. However, it is not preferable to concentrate it to a concentration that makes it difficult to apply the spray drying method described in the first section. (d Spray drying) The concentrated liquid (residual liquid) obtained by reverse osmosis etc. has a moisture content of 60 to 96%.
A conventionally known vacuum dryer (
For example, it is also possible to use a IIη type agitating dryer), but as a result of research, the inventors found that spray drying is particularly suitable for drying the above-mentioned saccharide fatty acid ester slurry for removing wood. . Incidentally, dehydration and drying using a normal stirring type vacuum dryer is difficult due to the high viscosity of the sucrose fatty acid Nissel aqueous solution, and as a result, the work is forced at high temperatures and for a long time, resulting in decomposition of the sucrose fatty acid ester. is known to cause undesirable phenomena such as an increase in acid value, strong premature coloring, and caramelization (Special Publication No. 37-998
Furthermore, even in the case of a so-called flash dryer that continuously heats slurry, supplies it to a vacuum chamber, and discharges it, the large latent heat of water (500 Kcal)
/Kg of water), it is difficult to dehydrate and dry sufficiently, and even if these difficulties could be overcome. Shi after being dehydrated and dried under vacuum: fIL! Since the 4-fatty acid ester is in a molten state, it requires a step of taking it out of the dryer, cooling it by blowing cold air or the like to below its melting point, solidifying it, and then pulverizing it. The dehydration and drying means for obtaining powdered 7Ms fatty acid ester are summarized above. ■ Dewatering and drying slurry under vacuum. ■ Melted from a vacuum dryer, 1! ! Removal of the fatty ester, ■ Cooling and solidification of the removed melt. ■ Since it requires multiple steps such as crushing the solidified sucrose fatty acid ester, it is economically undesirable, and especially ■
The crushing process is accompanied by concerns about dust explosions. However, according to the means for dehydrating and drying a citric acid fatty acid ester slurry by spray drying according to the present invention, the drawbacks of the above-mentioned drying means can be completely eliminated. That is, by continuously feeding the slurry to the spray drying tower via a pump and dispersing and atomizing the fed slurry via a nozzle or a rotating disk, preferably the latter, the evaporation of the water is greatly increased. Since it is possible to
After R, dehydration and drying can be completed within a few seconds. The temperature of the slurry supplied to the spray drying tower is 40
The temperature is selected in the range of °C to 80 °C, but from the viewpoint of quality, it is preferably within the range of 40 °C to 60 °C. When dispersing with a zero-rotation disc, the diameter of the disc is 5 °C. ~
When 10cIlφ, 15.00Orpm ~24.0
A rotation speed of 00 rpm+e is appropriate. The amount of air being blown is 8 (
Warm) air should have more than the amount of heat required to evaporate the moisture in the slurry, so naturally a large amount of air is required when the air temperature is low. The air temperature can be selected between 10℃ and 100℃, but in order to avoid deterioration of the product sucrose fatty acid ester, it should be set between 60℃ and 100℃.
It is desirable to choose a temperature between 80°C. Humidity in the blown air is also important, along with the air temperature mentioned above, but roughly speaking, it is expressed as absolute humidity. It is economical to choose the value of . Factors such as the volume, tower diameter, and height of the spray drying tower are designed based on 1 or more spray conditions.If 0 conditions are appropriate,
Powdered sucrose fatty acid ester with a moisture content of 5% or less is continuously taken out from the bottom of the spray drying tower.

[Effect]

Among the various reaction mixtures contained in the I sugar fatty acid ester reaction mixture, sucrose fatty acid ester forms micelles with water, and unreacted fatty acid methyl ester, soap, and fatty acids are wrapped in the wood micelles. On the other hand, the unreacted sucrose and the border generated from the catalyst pass through the ultrafiltration membrane together with the wood.Next, the residual liquid that was not ultrafiltered is Powdered sucrose fatty acid esters can be economically purified from a sucrose fatty acid reaction mixture of composition without using any solvent other than water by dehydrating and slurrying by reverse osmosis, then spraying and drying. can be manufactured. (Margin below)

【Example】

Hereinafter, the embodiments and effects of the invention will be explained with reference to Examples, but the examples are of course for illustrative purposes and are not intended to limit the connotation or extension of the idea of the invention. Example-1 Stearic acid methyl ester and sea ztl! Potassium carbonate (K2 CCh ) and sodium stearate were added to the aqueous mixture of i, heated according to a conventional method (aqueous medium synthesis), and transesterified under vacuum to obtain a reaction mixture having the following composition. Sucrose fatty acid ester (monoester amount = 58%) 31.5% unreacted sucrose 34.1% unreacted methyl stearate 2.8% stearic acid
1.8% to 2C030,9% stearic acid group 28.9% subtotal
100.0% or more reaction mixture 1
Add 4,100 kg of hydrochloric acid water to 0.00 kg and heat at 50°C.
The mixture was stirred for 60 minutes. A white SE precipitate cake formed. The P)I of the liquid was 3.3. The precipitate cake was separated and dissolved by adding water at 50°C to neutralize the p)l. This aqueous solution was transferred to a spiral-shaped 4" cylindrical unit with a membrane surface [8rn' equipped with an ultrafiltration membrane (product name <<TERP-E, 5) (fraction molecule 435,000) sold by Toshi Engineering ■ The operating conditions at this time were: Delivery pressure = 8.5kg/cm2G ~9.2kg/c
+'G liquid feeding temperature = 53.0°C to 53.5°C, pH of the liquid = 7.6, and solid content concentration in the liquid = 2.4% discharged from the strained membrane. Nine hours after the start of the liquid passage, 49.0% of the unreacted sugars dissolved in the e-liquid discharged from the e-filtration membrane were removed into the filtrate. was. In addition, the leakage of sucrose fatty acid ester into the filtrate was only 0.3% of the amount initially contained in the reaction mixture. *kiX is 52% of the amount initially contained in the reaction mixture.
．． 0% removed. By the above operations, the liquid volume of the concentrated reaction mixture is 2
,000 kg, and the amount of filtrate that passed through the filtration membrane was 2,200 kg. Next, 2,200 kg of this concentrated liquid was added again to 2,200 kg.
kg of deionized water was added and stirred for 60 minutes at 50°C to dissolve and adjust the pH to 7.4, and then fed once again to the above-mentioned filtration membrane. When operation was carried out under approximately the same conditions as described above, 1,510 kg of concentrated liquid was obtained after 8 hours of liquid passage. The composition of this concentrate is as follows. (Left below) Sucrose stearate 2.07% water-reacted sucrose 0.46% water-reacted methyl stearate (119% stearic acid
0.12% stearate
1.91% salt
0.01% water
95.24% total
It was found that not only 89% or more of the target sucrose stearate (100.0%) was recovered, but also 80% of unreacted sugars and approximately 89% of salts were removed. However, unreacted methyl stearate, stearic acid, and the king of stearates were not removed because they accompanied the sucrose stearate.Next, 1,510 kg of the above reconcentrated liquid was sent to Reverse osmosis membrane (product name <<PE100) related to Shi Engineering Oki Sales
0 >) Molecular weight cutoff = 60) Membrane surface I 8 m
' was supplied to a spiral-shaped cylindrical unit at a temperature of 50°C. The operating conditions at this time are: Delivery pressure = 57kHz/cm'G to 59kg/cm'G
pH of the liquid = 7.8 It was discharged from the reverse osmosis membrane. After 7 hours, the amount of concentrated liquid concentrated by the reverse osmosis membrane was 700.
kg (the calculated amount of liquid was 810 kg), and the composition of this concentrate was: (Left below) Stearic acid ester 4.43% water reaction 0.50% water reaction Methyl stearate 0.04% stearic acid
0.02% stearate
4.12% salt water 90
．． 89% total 100.00%
Met. Thus, it has been found that only approximately half of the water in the concentrate can be removed through the reverse osmosis membrane. This concentrated liquid was immediately supplied to a spray drying tower while maintaining the temperature at 50°C, and was spray dried. What are the drying conditions? Spray drying tower diameter: 2.0+s, straight cylinder: 1.5m. Rotating disc diameter 10cm, rotation speed 20. OOOrpm Inlet air temperature 80℃. ell 'Ilx ノ(Jt k6 speed o, 8 k
It was between g/B'j. The powdered sucrose fatty acid ester obtained from the lower part of the spray drying tower has an acid value of 5.0, no coloration due to heating, and a water content of 1.
It had good fluidity with a bulk ratio of 90% and a bulk ratio of 10.44.Dry storage could be maintained stably for about 2 hours, and there were no problems such as sticking to the inner wall of the spray drying tower, which was initially a concern. . The amount of monoester in the obtained sucrose fatty acid ester was 57%, which was completely unchanged from before drying. [Effects of the Invention] As explained above, the powdered powder according to the present invention Mtt! The method for producing i fatty acid ester includes SE precipitation with acidic water,
By cleverly combining ultrafiltration, reverse osmosis, and spray-drying methods, we are able to provide a technology that economically mass-produces high-purity sucrose fatty acid esters without using any organic solvents. Therefore, it has great industrial value. The advantages of the invention are listed below for reference. ■ It is possible to produce sucrose fatty acid esters using inexpensive water without using any solvents during synthesis, purification, and drying. ■ Since the sucrose fatty acid ester can be dried in a short time under normal pressure, there is no thermal deterioration of the product due to drying. ■ Since no organic solvent is used, there is no need for expensive explosion-proof electrical equipment. ■ Since no organic solvent is used, there is no risk of explosion or fire caused by the solvent. ■ Since no organic solvent is used, there is no risk of solvent mixing into the product. ■ Since no organic solvent is used, there is no negative impact on employees due to solvent vapor. ■ It is extremely easy to establish an industrial scale plant for various reasons. (Φ It is possible to create a safe and low-cost plant. Patent applicant Dai-ichi Kogyo Seiyaku Co., Ltd.

Claims (1)

[Claims] 1. Unreacted sucrose, unreacted fatty acid methyl ester,
After adding acidic water to the sucrose fatty acid ester-containing reaction mixture containing catalyst, soap, fatty acids, etc., which will be synthesized by the aqueous method, the precipitate cake is dissolved in water and brought into contact with an ultrafiltration membrane to remove unreacted substances. Sucrose and the salt generated from the catalyst are separated together with water by passing through the membrane, and the remaining sucrose fatty acid ester,
A method for producing powdered sucrose fatty acid ester, which comprises contacting an aqueous solution containing unreacted fatty acid methyl ester, soap, and fatty acid with a reverse osmosis membrane to form a slurry, and then spray-drying the slurry. 2 The composition of the reaction mixture is: Unreacted sucrose = 1-80% Unreacted fatty acid methyl ester = 0.5-10% Catalyst (K
_2CO_3) = 0.05-7% soap = 2-60
% fatty acid = 0.5-10% volatile content = 0.0-50% sucrose fatty acid ester = 15-95%. 3. The manufacturing method according to claim 1, wherein the liquid property of the sucrose fatty acid ester-containing reaction mixture is adjusted to a pH within the range of 3.0 to 5.5 with lactic acid, acetic acid, sulfuric acid, or hydrochloric acid. 4. The production according to claim 1, wherein the temperature of the aqueous solution of the sucrose fatty acid ester-containing reaction mixture is 40°C to 60°C, and the amount of water added thereto is such that water/reaction mixture = 5 to 40 (weight ratio). Method. 5 The ultrafiltration membrane is composed of polysulfone-based or polyvinylidene fluoride-based resin, and has a molecular weight cut-off of 1.0
2. The manufacturing method according to claim 1, wherein the amount is from 00 to 100,000. 6. The manufacturing method according to claim 1 or 5, wherein the pressure during ultrafiltration is 1 to 20 kg/cm^2. 7. The fatty acid residue constituting the fatty acid methyl ester has 16 to 22 carbon atoms, and the fatty acid residues of the soap and fatty acid are common to the fatty acid residue constituting the fatty acid methyl ester. Production method. 8. The manufacturing method according to claim 1, wherein the reverse osmosis membrane is made of a polyether resin and has a molecular weight cut off of 60. 9. The manufacturing method according to claim 1, wherein the pressure during reverse osmosis is 50 to 65 kg/cm^2G. 10. The manufacturing method according to claim 1, wherein the aqueous solution is brought into contact with a reverse osmosis membrane and the aqueous solution is further evaporated and concentrated to form a slurry. 11 The solid content in the slurry containing sucrose fatty acid ester, unreacted fatty acid methyl ester, soap and fatty acid is
The manufacturing method according to claim 1, wherein the content is 4 to 40%. 12 The humidity and temperature of the blown air during spray drying are absolute humidity = 0.008 to 0.05 (kg・water/kg・dry air)
The manufacturing method according to claim 1, wherein the temperature is 10°C to 100°C. 13. The manufacturing method according to claim 1, wherein the composition of the powdered sucrose fatty acid ester product is within the following range. Moisture = 0.5-5% Unreacted fatty acid methyl ester = 0.5-10% Soap = 0
．． 5-60% Fatty acid = 0.5-10% Sucrose fatty acid ester = 98.0-15.0%