阅读说明：本技术 一种高纯度油酸甲酯的制备方法 (Preparation method of high-purity methyl oleate ) 是由 夏冶 王元超 于 2020-07-02 设计创作，主要内容包括：本发明公开了一种高纯度油酸甲酯的制备方法,涉及油酸甲酯提纯技术领域。包括以下步骤,将尿素与油酸甲酯原料加入低碳醇溶液中,加热溶解至均一溶液,降温冷冻所述均一溶液,析出低碳链甲酯和饱和碳链甲酯的脲包物；过滤除去所述脲包物,对滤液进行蒸馏浓缩,得到油酸甲酯和亚油酸甲酯的浓缩物；将所述浓缩物溶解到萘烷中,再加入顺丁烯二酸酐和碘,升温反应至其中的亚油酸甲酯生成C<Sub>22</Sub>三元羧酸甲酯,加入氢氧化钠溶液；蒸馏S3得到的反应液,除去溶剂萘烷,过滤除去C<Sub>22</Sub>三元羧酸钠,得到高纯度的油酸甲酯。本发明通过尿素包合的方法除去油酸甲酯中的饱和脂肪酸甲酯,然后通过反应的方法除去多不饱和脂肪酸甲酯,从而得到高纯度的油酸甲酯。(The invention discloses a preparation method of high-purity methyl oleate, and relates to the technical field of methyl oleate purification. Adding urea and methyl oleate raw materials into a low-carbon alcohol solution, heating and dissolving the raw materials to obtain a uniform solution, cooling and freezing the uniform solution, and separating out urea inclusion compounds of low-carbon chain methyl esters and saturated carbon chain methyl esters; filtering to remove the urea inclusion, and distilling and concentrating the filtrate to obtain a concentrate of methyl oleate and methyl linoleate; dissolving the concentrate into decalin, adding maleic anhydride and iodine, heating to react until methyl linoleate generates C 22 Tricarboxylic acidsMethyl ester, adding sodium hydroxide solution; distilling the reaction solution obtained in S3, removing decalin as a solvent, and filtering to remove C 22 Sodium tricarboxylate to obtain high-purity methyl oleate. According to the invention, saturated fatty acid methyl ester in methyl oleate is removed by a urea inclusion method, and then polyunsaturated fatty acid methyl ester is removed by a reaction method, so that high-purity methyl oleate is obtained.)

1. A preparation method of high-purity methyl oleate is characterized by comprising the following steps,

s1, adding urea and methyl oleate raw materials into a low-carbon alcohol solution, heating and dissolving the raw materials to obtain a uniform solution, cooling and freezing the uniform solution, and separating out urea inclusion compounds of low-carbon chain methyl esters and saturated carbon chain methyl esters;

s2, filtering to remove the urea inclusion, and distilling and concentrating the filtrate to obtain a concentrate of methyl oleate and methyl linoleate;

s3, dissolving the concentrate into decalin, adding maleic anhydride and iodine, heating to react until methyl linoleate generates C₂₂Adding sodium hydroxide solution into the tricarboxylic acid methyl ester;

s4, distilling the reaction solution obtained in S3, removing decalin as a solvent, and filtering to remove C₂₂Sodium tricarboxylate to obtain high-purity methyl oleate.

2. The method according to claim 1, wherein the mass ratio of the urea to the methyl oleate raw material is m_Urea:m_{Oleic acid methyl ester}3 to 8:1, wherein m_UreaIs the mass of urea, m_{Oleic acid methyl ester}Is the mass of methyl oleate.

3. The method according to claim 1, wherein the mass ratio of the low carbon alcohol solution to the urea is m_{Low carbon alcohol solution}:m_Urea2 to 7:1, wherein m_{Low carbon alcohol solution}Mass m is lower alcohol solution_UreaIs the mass of urea.

4. The method of claim 1, wherein the lower alcohol solution is C₁～C₄The water content of the aqueous solution of the monoalcohol is 10 to 25 percent.

5. The method for producing high-purity methyl oleate according to claim 1, wherein the heating and dissolving temperature is 40 to 110 ℃ and the freezing temperature is-30 to-10 ℃.

6. The method of claim 1, wherein the mass/volume ratio of the concentrate to decalin is m_Concentrate:V_Decalin0.3 to 2:1, wherein m_ConcentrateIs the mass of the concentrate in kg; v_DecalinIs the volume of decalin in L.

7. The method of claim 1, wherein the amount of maleic anhydride to methyl linoleate present in the concentrate is n_{Maleic anhydride}:n_{Linoleic acid methyl ester}1.0-2.0: 1, wherein n_{Maleic anhydride}Amount of substance which is maleic anhydride, n_{Linoleic acid methyl ester}Is the amount of methyl linoleate species in the concentrate.

8. The method of claim 1, wherein the iodine is used in an amount of 0.05 to 0.2% by mass of the concentrate.

9. The method according to claim 1, wherein the reaction temperature of the temperature-raising reaction is 100 to 170 ℃ and the reaction time is 4 to 10 hr.

Technical Field

The invention relates to the technical field of methyl oleate purification, and particularly relates to a preparation method of high-purity methyl oleate.

Background

Methyl oleate is an important fine chemical product and raw material, and is mainly derived from animal and vegetable oil. However, the unrefined methyl oleate, whether from vegetable or animal fats and oils, is a mixture of methyl oleates of a series of different carbon chains, such as methyl laurate, methyl myristate, methyl palmitate, methyl stearate, and mixtures of methyl oleate and methyl linoleate. And the methyl ester of the saturated carbon chain has the characteristic of high melting point, and the subsequent esterified product has the defect of easy solidification at normal temperature. Polyunsaturated carbon chain methyl esters such as methyl linoleate and its products have the disadvantage of being easily oxidized, which leads to a darker product color. These disadvantages all lead to a product with limited use in some food, pharmaceutical and cosmetic applications. Therefore, the prepared high-purity methyl oleate has important significance on the synthesis of esterified products with good fluidity and high quality color, and can also widen the application range of the products in medicines and high-end cosmetics.

Chinese patent publication nos. CN104046508A and CN104529739A disclose methods for purifying unsaturated fatty acids, the former involving electromagnetic crystallization and requiring equipment renewal, and the latter requiring multiple washing and cumbersome operation.

Disclosure of Invention

The invention aims to provide a preparation method of high-purity methyl oleate, which removes saturated fatty acid methyl ester in methyl oleate by a urea inclusion method and then removes polyunsaturated fatty acid methyl ester by a reaction method so as to obtain high-purity methyl oleate.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of high-purity methyl oleate is characterized by comprising the following steps,

s1, adding urea and methyl oleate raw materials into a low-carbon alcohol solution, heating and dissolving the raw materials to obtain a uniform solution, cooling and freezing the uniform solution, and separating out urea inclusion compounds of low-carbon chain methyl esters and saturated carbon chain methyl esters;

s2, filtering to remove the urea inclusion, and distilling and concentrating the filtrate to obtain a concentrate of methyl oleate and methyl linoleate;

s3, dissolving the concentrate into decalin, adding maleic anhydride and iodine, heating to react until methyl linoleate generates C₂₂Adding sodium hydroxide solution into the tricarboxylic acid methyl ester;

s4, distilling the reaction solution obtained in S3, removing decalin as a solvent, and filtering to remove C₂₂Sodium tricarboxylate to obtain high-purity methyl oleate.

Further, the mass ratio of the urea to the methyl oleate raw material is m_Urea:m_{Oleic acid methyl ester}3 to 8:1, wherein m_UreaIs the mass of urea, m_{Oleic acid methyl ester}Is the mass of methyl oleate.

Further, the mass ratio of the low-carbon alcohol solution to the urea is m_{Low carbon alcohol solution}:m_Urea2 to 7:1, wherein m_{Low carbon alcohol solution}Mass m is lower alcohol solution_UreaIs the mass of urea.

Further, the low carbon alcohol solution is C₁～C₄The water content of the aqueous solution of the monoalcohol is 10 to 25 percent.

Furthermore, the heating and dissolving temperature is 40-110 ℃, and the freezing temperature is-30 to-10 ℃.

Further, the mass-volume ratio of the concentrate to the decalin is m_Concentrate:V_Decalin0.3 to 2:1, wherein m_ConcentrateIs the mass of the concentrate in kg; v_DecalinIs the volume of decalin in L.

Further, the mass ratio of the maleic anhydride to the methyl linoleate in the concentrate is n_{Maleic anhydride}:n_{Linoleic acid methyl ester}1.0-2.0: 1, wherein n_{Maleic anhydride}Amount of substance which is maleic anhydride, n_{Linoleic acid methyl ester}Is the amount of methyl linoleate species in the concentrate.

Furthermore, the dosage of the iodine is 0.05-0.2% of the mass of the concentrate.

Further, the reaction temperature of the temperature rise reaction is 100-170 ℃, and the reaction time is 4-10 hr.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, through twice separation, saturated fatty acid methyl ester is removed by adopting urea inclusion, and polyunsaturated fatty acid methyl ester is removed by Diels-Alder reaction, so that methyl oleate with good color and luster and high purity can be easily obtained under the condition of low equipment requirement.

Drawings

FIG. 1 is a flow chart of the method of the present invention.

FIG. 2 is a gas chromatographic analysis of the product methyl oleate E.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Table 1 below shows the composition of a typical methyl oleate (available from pt. wilmar nabatii Indonesia) which was used as a starting material in the subsequent examples to prepare high purity methyl oleate.

TABLE 1 composition of a typical methyl oleate

Composition of	Content (%)	Composition of	Content (%)
				C12：0Methyl ester	0.42	C14：0Methyl ester	0.44
C16：0Methyl ester	7.31	C18：0Methyl ester	2.45
				C18：1Methyl ester	77.86	C18：2Methyl ester	11.05
C20：0Methyl ester	0.47

Referring to fig. 1, the present invention provides a method for preparing high purity methyl oleate, comprising the following steps,

s1, adding the urea and methyl oleate raw materials into the low-carbon alcohol solution, heating and dissolving to obtain a uniform solution, cooling and freezing the uniform solution, and separating out urea inclusion compounds of low-carbon chain methyl esters and saturated carbon chain methyl esters.

Too high a water content, insufficient urea usage and too high a freezing temperature will result in an insufficient separation of saturated fatty acid methyl esters. To effectively liftThe separation efficiency of the high saturated fatty acid methyl ester is reasonably controlled by the invention through the dosage and temperature of each reagent, preferably, the mass ratio of the urea to the methyl oleate raw material is m_Urea:m_{Oleic acid methyl ester}3 to 8:1, wherein m_UreaIs the mass of urea, m_{Oleic acid methyl ester}Is the mass of methyl oleate. The mass ratio of the low-carbon alcohol solution to the urea is m_{Low carbon alcohol solution}:m_Urea2 to 7:1, wherein m_{Low carbon alcohol solution}Mass m is lower alcohol solution_UreaIs the mass of urea. The low carbon alcohol solution is C₁～C₄The water content of the aqueous solution of the monoalcohol is 10 to 25 percent; the heating and dissolving temperature is 40-110 ℃, and the freezing temperature is-30 to-10 ℃.

S2, filtering to remove the pustule, and distilling and concentrating the filtrate to obtain a concentrate of methyl oleate and methyl linoleate;

s3, dissolving the concentrate into decalin, adding maleic anhydride and iodine, heating to react until methyl linoleate generates C₂₂Adding sodium hydroxide solution into the tricarboxylic acid methyl ester; removing the methyl linoleate;

the dosage of maleic anhydride and iodine, and the temperature and time of the reaction will influence whether the reaction of methyl linoleate is complete. In order to ensure that the reaction of the methyl linoleate is complete, the dosage of maleic anhydride and iodine, and the temperature and time of the heating reaction are controlled; preferably, the mass-to-volume ratio of the concentrate to the decalin is m_Concentrate:V_Decalin0.3 to 2:1, wherein m_ConcentrateIs the mass of the concentrate in kg; v_DecalinIs the volume of decalin, in units of L; the mass ratio of the maleic anhydride to the methyl linoleate in the concentrate is n_{Maleic anhydride}:n_{Linoleic acid methyl ester}1.0-2.0: 1, wherein n_{Maleic anhydride}Amount of substance which is maleic anhydride, n_{Linoleic acid methyl ester}Is the amount of methyl linoleate species in the concentrate; the dosage of the iodine is 0.05 to 0.2 percent of the mass of the concentrate; the reaction temperature of the temperature rise reaction is 100-170 ℃, and the reaction temperature isThe time is 4-10 hr.

S4, distilling the reaction solution obtained in S3, removing decalin as a solvent, and filtering to remove C₂₂Sodium tricarboxylate to obtain high-purity methyl oleate.

The method of the present invention will be described in detail with reference to specific examples.