JPS5920657B2 - Method for producing fatty acid derivatives - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an addition product in which acrylic acid is added to a higher unsaturated fatty acid, and its purpose is to provide an industrial method for producing a high-quality addition product in good yield. It is in.

The addition product of acrylic acid to a higher unsaturated fatty acid is particularly one in which acrylic acid is added to an unsaturated fatty acid having 18 carbon atoms.
The addition product of Alder addition is called C24 dicarboxylic acid, and is already industrially produced and commercially available in the United States.

C2, a dicarboxylic acid, is the only commercially available dibasic acid that falls between the C12 sebacic acid and the C36 dimer acid, and has many recognized uses. (B,
F. Wards JAOCS, Deaf, 219 (1975)
,U,S,Pat,3,833,524・3,734
, 859) That is, C2, dicarboxylic acid itself or its ester, metal salt, and its derivative are ink resin,
It has been shown that it can be used in adhesives, lubricants, corrosion inhibitors, emulsifiers, plasticizers, synthetic coolants, floor polishes, industrial and household cleaning agents, etc. C2,
Regarding the manufacturing method of dicarboxylic acid, B, F, Ward
By the so-called batch method in which linoleic acid or tall oil fatty acid is added with an equimolar amount of acrylic acid, 0.01% to 0.5% of iodine is used as a catalyst, and heated to 200 to 270°C in an autoclave. Only the manufacturing method is recognized. (U, S, Pa, 3, 753, 96
8) The inventors also found that the conjugated methyl octadecadienoate contained methyl acrylate in an autoclave without a catalyst.
It has been found that C2 and dicarboxylic acid can be easily produced by heating at 250°C. [Suzuki, Hashimoto, Yukagaku 19, 950 (1970)] However, no catalyst other than iodine by B. F. Ward et al. has been recognized as an effective catalyst for addition reactions. Although it is clear that continuous methods are more advantageous than batch methods in such addition reactions, no effective continuous method has yet been proposed. As a result of intensive research to develop a method for continuously adding acrylic acid to higher unsaturated fatty acids under normal pressure, the inventor adopted the flow method (Ftow system) as the reaction method and phosphoric acid as a catalyst. The present inventors have discovered that the objective can be achieved by employing pure synthetic silica/alumina supported with silica and alumina, and have completed the present invention.

That is, according to the present invention, when adding acrylic acid to a higher unsaturated fatty acid, a mixed solution of the fatty acid and acrylic acid is mixed with a weight ratio of alumina to silica supporting phosphoric acid of 0.3 to 1.0. , the surface area is 240
d/, there is provided a method for producing an acrylic acid-added fatty acid, which is characterized by bringing the acrylic acid-added fatty acid into flow contact with a heated catalyst layer made of pure synthetic silica and alumina as described above.

The higher unsaturated fatty acid used as a raw material in the present invention has 8 carbon atoms.
-22 linear or branched polyethylenically unsaturated fatty acids, such as conjugated fatty acids such as linoleic acid, linolenic acid or alpha and beta monoeleostearic acid.

Further, these fatty acids may have an alcoholic hydroxyl group, and the method of the present invention can also be applied to ricinoleic acid, ricinelaidic acid, and the like. Furthermore, the method of the invention includes mixtures of these fatty acids,
Alternatively, mixtures containing these as main components, for example fatty acids obtained from fats and oils such as tall oil, soybean oil, linseed oil, cottonseed oil, safflower oil, castor oil, and tung oil, are advantageously applied. In the present invention, it is necessary to use silica-alumina obtained by pure synthesis as a catalyst.

The clay catalysts commonly used as catalysts for reactions of this type do not give favorable results. It is also important to select the catalyst composition appropriately. For example, in the catalyst of the present invention, the weight ratio of alumina to silica is relatively large, for example, 0.3 to 1.0, preferably 0. .4~0.
6 range silica-alumina is used. Particularly preferred catalysts include 269-72% of SlO and 27-30% of A4O.
, is a pure synthetic silica-alumina having a weight composition of less than Fe2O3l, less than CaOl, and less than MgOl.

The above-mentioned pure synthetic silica alumina having a high alumina content exhibits an excellent effect as a catalyst for the addition reaction of acrylic acid to higher unsaturated fatty acids, regardless of its crystal structure.

In the method of the present invention, it is necessary to use the pure synthetic silica-alumina catalyst as described above in the form of supporting phosphoric acid.

When the addition reaction of acrylic acid to higher unsaturated fatty acids is carried out using the above-mentioned pure synthetic silica/alumina that does not support phosphoric acid as a catalyst, a part of the fatty acid is added to the calcium and other substances contained in the catalyst during the addition reaction. It reacts with metals such as magnesium to produce metal soap, but this formation is particularly significant when the reaction temperature exceeds 200°C, and the produced metal soap covers the catalyst surface, reducing the catalytic activity. Therefore, in order to carry out the reaction while suppressing the reduction in catalytic activity caused by the metal soap, it is necessary to carry out the reaction at 200°C or lower, but in this case, the yield of the target product decreases. Furthermore, this metal sieve causes the problem of shortening the life of the catalyst. According to the present invention, these drawbacks are overcome by supporting phosphoric acid on pure synthetic silica-alumina.

The amount of phosphoric acid supported is the pure synthetic silica/alumina catalyst 1
0.1 to 2.0 milliequivalent to r, preferably 0.5
~1.5 meq. During the reaction, this phosphoric acid
It has the effect of significantly suppressing the formation of soap. Moreover, such an effect can be achieved to some extent by the presence of methanol in the reaction system. The method of the present invention is carried out by filling a flow reaction tube with the phosphoric acid supported catalyst and continuously flowing a mixed solution of unsaturated fatty acid and acrylic acid as raw materials through the reaction tube under heating.

Thereby, acrylic acid adducts to higher unsaturated fatty acids can be obtained depending on the reaction time. The reaction temperature is 150 to 330°C. When carrying out the reaction according to the method of the present invention, the catalytic activity hardly decreases even if a mixed solution of raw material unsaturated fatty acid and acrylic acid is passed in an amount of 10 times or more the weight of the packed catalyst.

Furthermore, when the catalyst of the present invention has a decreased catalytic activity, it can be easily regenerated by immersion cleaning in an organic solvent and then power calcining. Since the method of the present invention is a distribution method, it has various advantages over the conventional batch method.

For example, in the process of the present invention, the product adduct can be continuously recovered separate from the catalyst and no special catalyst separation step is required. Furthermore, the method of the present invention
By adopting the flow method and using a highly active catalyst, the reaction can be carried out at a lower temperature and in a shorter contact time than in the batch method.
The resulting adduct is of high quality, transparent and slightly yellow in color. Moreover, the adduct produced according to the present invention was mainly composed of a 1:1 adduct of higher unsaturated fatty acid and acrylic acid. That is, in the case of an acrylic acid adduct to linoleic acid or ricinoleic acid, which is a Dels-Alder addition product of acrylic acid to an unsaturated fatty acid, it was a so-called C2l dicarboxylic acid main product having the following structure, for example. In addition, when carrying out the method of the present invention, it is preferable to heat the catalyst layer in advance at about 10° C. above the addition reaction temperature while passing nitrogen gas to remove moisture.

Next, the present invention will be explained in more detail with reference to Examples.
, Example 1 An addition reaction of acrylic acid was carried out using a high-surface silica-alumina catalyst (abbreviated as SAH, surface area of 240 I/t or more, commercially available product, manufactured by Nikka Seiko KK) on safflower mono-oil mixed fatty acids.

The reaction was carried out in a vertically erected quartz reaction tube of length 50 (V7!, inner diameter 1 cm) while heating the reaction tube with a ribbon heater (400 W) by controlling the temperature with a thermistor tightly attached to the center of the tube. The mixed solution of fatty acid and acrylic acid as raw materials was connected from the raw material reservoir to the reaction tube in a preheating tube with an inclination of 30 mm (inner diameter 1?, length 40 mm).
The solution was set so that it flowed down to the top of the reaction tube. The flow rate of the raw material fatty acid and acrylic acid mixed solution in the reaction tube was controlled to be constant. The volume in the reaction tube is 50
d, and was filled with a catalyst having a particle size of 24 to 42 mesh. In the case of SAH of the same particle size, the reaction tube was filled with 257. This particle size was used in consideration of the velocity of the mixed solution flowing through the reaction tube. The addition reaction is carried out by heating the reaction tube filled with the catalyst in a nitrogen stream at a temperature 10°C higher than the reaction temperature for 2 hours or more, and after sufficient dehydration, the raw material fatty acid and acrylic acid mixture is poured down. Ta. Compositional analysis of raw fatty acids and reaction products was carried out by methyl esterification using a conventional method, followed by constant temperature and heating. This was done using a chromatograph.

(Suzuki, Yukagaku, 20, 492 (1971)) The composition of safflower monofatty acid is as follows. The molar ratio of safflower monofatty acid and acrylic acid was 1:1, and the reaction temperature and SA
Table 1 shows the results of the addition reaction carried out as described above while varying the amount of phosphoric acid supported on H.

Table 1 shows that the yield of acrylic acid adducts to safflower monofatty acid increases when the amount of phosphoric acid supported increases, and at 2 meq.
It can be seen that at 0°C, the yield of adducts to fatty acids was 46%, which was a good yield.

In addition, the flow rate of the mixed liquid of fatty acid and acrylic acid is 5a/
8- in both cases. Example 2 Castor oil fatty acid was catalyzed with high surface purity synthetic silica/alumina catalyst (SAH).
) with acrylic acid according to Example 1.

The results are shown in Table 2. The castor oil fatty acid composition of the sample is as follows. The molar ratio of castor oil fatty acid to acrylic acid was 1, and the reaction temperature and amount of phosphoric acid supported on SAH were varied.

The results are shown in Table 2.

Table 2 clearly shows that the catalyst according to the present invention is extremely active in the addition of acrylic acid to castor oil fatty acid, ie, the main component ricinoleic acid, and selectively forms adducts.

Claims (1)

[Claims] 1. When adding acrylic acid to higher unsaturated fatty acids, the fatty acid and acrylic acid mixed liquid supports phosphoric acid, and the weight ratio of alumina to silica is 0.3 to 1.0.
A method for producing an acrylic acid-added fatty acid, which comprises bringing the acrylic acid-added fatty acid into contact with a heated catalyst layer made of pure synthetic silica/alumina having a surface area of 240 m^2/g or more.