Formulation and method of making high purity oleic acid

Abstract

The application discloses a formula and a preparation method of high-purity oleic acid, relates to the field of oleic acid production, and specifically discloses a formula of high-purity oleic acid, which comprises the following components in parts by mass: 1000 parts of soybean oil acid, 5-20 parts of 9932 type hydrogenation nickel catalyst of Zhuangxinwanfeng, and 1.5-10 parts of hydrogen gas filled into a reaction kettle with a pressure of 1.6-2.8 Mpa; the auxiliary catalyst is composed of ferrous chloride and magnesium sulfate, and the mass ratio of ferrous chloride to magnesium sulfate is 1:1-1.5; the application can adopt low-cost low-oleic soybean oil acid as a production raw material, and creatively converts linoleic acid into oleic acid through a partial hydrogenation mode; only part of the linoleic acid is selectively converted into oleic acid, excessive hydrogenation to generate stearic acid is greatly reduced, and high-purity oleic acid with a purity of greater than or equal to 98% is obtained.

Description

Technical Field

[0001] This invention relates to the field of high-purity oleic acid production, and to a formulation and preparation method for high-purity oleic acid. Background Technology

[0002] Oleic acid (cis-9-octadecenoic acid, C18:1) is an important basic chemical raw material, widely used in industries such as surfactants, cosmetics, pharmaceutical intermediates, lubricants, and plasticizers. High-end fields require oleic acid purity of over 98%.

[0003] Currently, industrially, oleic acid is mainly produced by hydrolyzing soybean oil, rapeseed oil, and palm oil to obtain mixed fatty acids, which are then purified through distillation and crystallization. Conventional soybean oleic acid raw materials typically contain ≤35% oleic acid (C18:1) and as much as 50%~55% linoleic acid (C18:2). Excessive hydrogenation produces stearic acid, and the raw materials also contain saturated fatty acids such as palmitic acid. Direct crystallization can separate saturated and unsaturated fatty acids, but it is difficult to separate oleic acid and linoleic acid. The market needs a soybean oleic acid product with low stearic acid and low oleic acid content, suitable for continuous large-scale industrial production; this invention solves this problem. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a formulation and preparation method for high-purity oleic acid. The present invention converts linoleic acid into oleic acid through partial hydrogenation, solving the problem of the difficulty in separating oleic acid and linoleic acid, and obtaining high-purity soybean oleic acid with low stearic acid and low oleic acid content.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A high-purity oleic acid formulation comprises, by mass parts: 1000 parts soybean oleic acid, 5-20 parts Johnson Matthey 9932 type hydrogenation nickel catalyst, and 1.5-10 parts co-catalyst or hydrogen gas filled into the reactor at a pressure of 1.6-2.8 MPa; the co-catalyst is composed of ferrous chloride and magnesium sulfate, with a ferrous chloride:magnesium sulfate mass ratio of 1:1-1.5.

[0006] As a preferred option, the aforementioned high-purity oleic acid formulation comprises, by mass parts: 1000 parts soybean oleic acid, 10 parts Johnson Matthey 9932 type hydrogenated nickel catalyst, 4 parts co-catalyst, and hydrogen gas filled into the reactor at a pressure of 2.4 MPa; the co-catalyst is composed of ferrous chloride and magnesium sulfate, with a mass ratio of ferrous chloride to magnesium sulfate of 1:1.25.

[0007] The aforementioned high-purity oleic acid formula, when prepared according to the above formula, yields an oleic acid C18:1 content ≥98%.

[0008] A method for preparing high-purity oleic acid includes the following steps: 1) Semi-hydrogenation process: Using 1000 parts of soybean oleic acid as raw material, under the action of 5-20 parts of Johnson Matthey's 9932 type hydrogenation nickel catalyst and 1.5-10 parts of co-catalyst, it reacts with hydrogen under high temperature and high pressure conditions. After the reaction is completed, it is cooled and filtered to obtain semi-hydrogenated soybean oleic acid. 2) Crystallization and centrifugation process: Semi-hydrogenated soybean oleic acid is cooled and crystallized, and then the solid and liquid phases are separated by centrifugation. The liquid phase is then separated by multiple crystallization processes to obtain high-purity oleic acid.

[0009] Further optimization revealed that the soybean oleic acid contained ≤35% C18-1 (oleic acid), ≤55% C18-2 (linoleic acid), and 10.89% saturated fatty acids.

[0010] Further optimization involves using hydrogen with a purity ≥99.9% in the semi-hydrogenation process, a reaction temperature of 180-210℃, a reaction pressure of 1.6-2.8 MPa, and a reaction time of 1-2 hours.

[0011] A further preferred embodiment of the cooling crystallization process in the crystallization centrifugation step includes the following steps: Step 1, Homogenization of raw materials: Temperature: 50℃, stirring speed: 150r / min, holding time: 15min; Step 2, temperature: 25℃, stirring speed: 30r / min, holding time: 120min; Step 3, temperature: 20℃, stirring speed: 30r / min, holding time: 120min; Step 4: Temperature: 15℃, stirring speed: 25r / min, holding time: 60min; Step 5, crystal growth: Temperature: 13.6℃, ​​stirring speed: 15r / min, holding time: 720min.

[0012] Further optimization involves setting the temperature of the centrifugation step in the crystallization centrifugation process to 14±1℃, the centrifuge speed to 6000-7000 r / min, and the centrifugation time to 120-180 seconds.

[0013] Further optimization involves obtaining high-purity oleic acid by multiple crystallization separations of the liquid phase during the crystallization centrifugation process, with the number of repetitions being ≤6 times, preferably 3-4 times, and the purity of the final product, high-purity oleic acid, being ≥98%.

[0014] The advantages of this invention are: This invention innovatively employs Johnson Matthey's 9932 nickel hydrogenation catalyst combined with a composite co-catalyst of ferrous chloride and magnesium sulfate. The catalyst and co-catalyst work synergistically to achieve precise control of hydrogenation activity, and neither is dispensable. The formula and method of this invention use low-oleic soybean oleic acid as a raw material, which can be directly used as a production raw material, broadening the source of raw materials and reducing procurement costs. After processing by this invention, low-oleic soybean oleic acid can selectively convert only a portion of linoleic acid into oleic acid, significantly reducing excessive hydrogenation to stearic acid, resulting in high-purity oleic acid with a purity ≥98%. The formulation and method of this invention for preparing high-purity oleic acid are simple to implement industrially. The entire process only requires conventional oil and fat equipment such as a high-pressure hydrogenation reactor, a low-temperature crystallization reactor, and a tubular high-speed centrifuge. It does not require an ultra-high vacuum distillation column, resulting in lower equipment investment, strong production stability, and suitability for continuous large-scale industrial production. Detailed Implementation

[0015] The present invention will be described in detail below with reference to specific embodiments.

[0016] Example 1 This embodiment discloses a method for preparing high-purity oleic acid, the specific operation of which is as follows: Raw material carbon chain data (test method is GB 5009.168-2016 "National Food Safety Standard Determination of Fatty Acids in Food"): Oleic acid C18:1 content 34.24%, saturated fatty acids 10.89%, linoleic acid 54.61%, and other components 0.26%.

[0017] (1) Semi-hydrogenation process 1000 kg of the above-mentioned soybean oleic acid was added to a reactor, along with 5 kg of Johnson Matthey 9932 type hydrogenation nickel catalyst. The ratio of ferrous chloride to magnesium sulfate co-catalyst was 1:1, with a total addition of 1.5 kg. The reactor was sealed, and 99.99% pure hydrogen gas was introduced to purge the air from the reactor, maintaining a hydrogen pressure of 1.6 MPa. The temperature was raised to 180°C, and the reaction was carried out for 2 hours. After the reaction was completed, the hydrogen gas was purged, and the mixture was cooled and filtered to obtain semi-hydrogenated soybean oleic acid.

[0018] Carbon chain sampling tests revealed that semi-hydrogenated soybean oleic acid contained 47.36% oleic acid, 51.93% saturated fatty acids, 0.47% linoleic acid, and 0.24% other components.

[0019] (2) Crystallization centrifugation process All semi-hydrogenated soybean oleic acid was transferred to a crystallization vessel, and homogenization, gradient cooling, and crystal growth were strictly performed according to the parameters in Table 1. After crystal growth, the material was transferred to a high-speed tubular centrifuge, and the centrifugation temperature was controlled at 14℃, the speed at 6000 r / min, and each centrifugation lasted 150 s. The saturated fatty acid solid phase was separated, and the oleic acid-rich liquid phase was collected. The liquid phase was sent back to the crystallization vessel to repeat the complete crystallization and centrifugation process, for a total of 3 cycles. The liquid phase from the last centrifugation was collected, and the carbon chain of the obtained product was tested.

[0020] Carbon chain analysis of the finished product: oleic acid C18:1 content 98.03%, saturated fatty acids 0.87%, linoleic acid C18:2 content 0.96%, and other components content 0.14%; product yield 32.4%.

[0021] Example 2 This embodiment discloses a method for preparing high-purity oleic acid, the specific operation of which is as follows: (1) Semi-hydrogenation process 1000 kg of the above-mentioned soybean oleic acid was added to a reactor, along with 10 kg of Johnson Matthey 9932 type hydrogenated nickel catalyst. The ratio of ferrous chloride to magnesium sulfate co-catalyst was 1:1.25, with a total addition of 4 kg. The reactor was sealed, and 99.99% pure hydrogen gas was introduced to purge the air from the reactor, maintaining a hydrogen pressure of 2.4 MPa. The temperature was raised to 195°C, and the reaction was carried out for 1.5 hours. After the reaction was completed, the hydrogen gas was purged, and the mixture was cooled and filtered to obtain semi-hydrogenated soybean oleic acid.

[0022] Carbon chain sampling tests revealed that semi-hydrogenated soybean oleic acid contained 45.55% oleic acid, 53.80% saturated fatty acids, 0.39% linoleic acid, and 0.26% other components.

[0023] (2) Crystallization centrifugation process All semi-hydrogenated soybean oleic acid was transferred to a crystallization vessel, and homogenization, gradient cooling, and crystal growth were strictly performed according to the parameters in Table 1. After crystal growth, the material was fed to a high-speed tubular centrifuge, and the centrifugation temperature was controlled at 14℃, the speed at 6500 r / min, and each centrifugation lasted 120s to separate the saturated fatty acid solid phase and collect the oleic acid-rich liquid phase. The liquid phase was sent back to the crystallization vessel to repeat the complete crystallization and centrifugation process, for a total of 4 cycles. The liquid phase from the last centrifugation was collected, and the carbon chain of the obtained product was tested.

[0024] Table 1. Operation steps for semi-hydrogenated soybean oleic acid crystallization Carbon chain analysis of the finished product: oleic acid C18:1 content 98.77%, saturated fatty acids 0.12%, linoleic acid C18:2 content 0.04%, and other components content 0.07%; product yield 29.9%.

[0025] Example 3 This embodiment discloses a method for preparing high-purity oleic acid, the specific operation of which is as follows: (1) Semi-hydrogenation process 1000 kg of the above-mentioned soybean oleic acid was added to a reactor, along with 20 kg of Johnson Matthey 9932 type hydrogenated nickel catalyst. The ratio of ferrous chloride to magnesium sulfate co-catalyst was 1:1.5, with a total addition of 10 kg. The reactor was sealed, and 99.99% pure hydrogen gas was introduced to purge the air from the reactor, maintaining a hydrogen pressure of 2.8 MPa. The temperature was raised to 210°C, and the reaction was carried out for 1 hour. After the reaction was completed, the hydrogen gas was purged, and the mixture was cooled and filtered to obtain semi-hydrogenated soybean oleic acid.

[0026] Carbon chain sampling tests revealed that semi-hydrogenated soybean oleic acid contained 46.28% oleic acid, 52.58% saturated fatty acids, 0.93% linoleic acid, and 0.21% other components.

[0027] (2) Crystallization centrifugation process All semi-hydrogenated soybean oleic acid was transferred to a crystallization vessel, and homogenization, gradient cooling, and crystal growth were strictly performed according to the parameters in Table 1. After crystal growth, the material was transferred to a high-speed tubular centrifuge, and the centrifugation temperature was controlled at 14℃, the speed at 7000 r / min, and each centrifugation lasted 180s to separate the saturated fatty acid solid phase and collect the oleic acid-rich liquid phase. The liquid phase was sent back to the crystallization vessel to repeat the complete crystallization and centrifugation process, for a total of 3 cycles. The liquid phase from the last centrifugation was collected, and the carbon chain of the obtained product was tested.

[0028] Carbon chain analysis of the finished product: oleic acid C18:1 content 98.23%, saturated fatty acids 0.80%, linoleic acid C18:2 content 0.82%, and other components 0.15%; product yield 33.5%.

[0029] Comparative Example 1 Using soybean oleic acid raw materials from the same batch, without selective semi-hydrogenation, homogenization, gradient cooling, and crystal growth were strictly performed according to the parameters in Table 1. After crystal growth, the material was fed into a high-speed tubular centrifuge, with the centrifugation temperature controlled at 14℃, the speed at 6000 r / min, and each centrifugation lasting 150 s. The saturated fatty acid solid phase was separated, and the oleic acid-rich liquid phase was collected. The liquid phase was then sent back to the crystallization kettle to repeat the complete crystallization and centrifugation process, for a total of 7 cycles. The carbon chain of the obtained product was then tested.

[0030] Carbon chain analysis of the finished product: oleic acid (C18:1) content 37.22%, saturated fatty acids 3.14%, linoleic acid 59.36%, and other components 0.28%. The analysis revealed that oleic acid and linoleic acid could not be separated in this product, therefore the experiment failed.

[0031] Comparative Example 2 Using soybean oleic acid from the same batch, 1000 kg of the aforementioned soybean oleic acid was added to a reactor, along with 10 kg of Johnson Matthey's 9932 type nickel hydrogenation catalyst. The reactor was sealed, and 99.99% pure hydrogen gas was introduced to purge the air from the reactor, maintaining a hydrogen pressure of 2.0 MPa. The temperature was raised to 180°C, and the reaction was carried out for 2 hours. After the reaction was completed, the hydrogen gas was purged, and the mixture was cooled and filtered. The carbon chain of the obtained product was then tested.

[0032] Carbon chain analysis of the finished product: Oleic acid C18:1 content 0%, saturated fatty acids 99.85%, linoleic acid 0.01%, and other components 0.24%. The analysis revealed that the product no longer contains oleic acid, therefore no further processing is necessary.

[0033] Comparative Example 3 Using soybean oleic acid from the same batch, 1000 kg of the aforementioned soybean oleic acid was added to a reactor, along with 5 kg of a 1:1 mixture of ferrous chloride and magnesium sulfate. The reactor was sealed, and 99.99% pure hydrogen gas was introduced to purge the air from the reactor, maintaining a hydrogen pressure of 2.0 MPa. The temperature was raised to 180°C, and the reaction was carried out for 2 hours. After the reaction was completed, the hydrogen gas was purged, and the mixture was cooled and filtered. The carbon chain of the obtained product was then tested.

[0034] Carbon chain analysis of the finished product: oleic acid C18:1 content 34.23%, saturated fatty acids 10.89%, linoleic acid 54.62%, and other components 0.26%. The analysis revealed that the carbon chain of this product was almost unchanged compared to that of the raw material soybean oleic acid, therefore no further processing is necessary.

[0035] In summary, the experiments above demonstrate that the catalyst and co-catalyst work synergistically to achieve precise control of hydrogenation activity; neither can be omitted, and high-purity oleic acid cannot be obtained without either. Using low-cost, low-oleic soybean oleic acid as the raw material according to the formula and method of this invention, the processing of this invention selectively converts only a portion of linoleic acid into oleic acid, significantly reducing excessive hydrogenation to stearic acid, resulting in high-purity oleic acid with a purity ≥98%.

[0036] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A formulation for high-purity oleic acid, characterized in that, The mixture comprises, by weight, 1000 parts soybean oleic acid, 5-20 parts Johnson Matthey 9932 type hydrogenation nickel catalyst, 1.5-10 parts co-catalyst, and hydrogen gas filled into the reactor at a pressure of 1.6-2.8 MPa; the co-catalyst is composed of ferrous chloride and magnesium sulfate, wherein the mass ratio of ferrous chloride to magnesium sulfate is 1:1-1.

5.

2. The formulation of high-purity oleic acid according to claim 1, characterized in that, The mixture comprises, by weight, 1000 parts soybean oleic acid, 10 parts Johnson Matthey 9932 type hydrogenation nickel catalyst, 4 parts co-catalyst, and hydrogen gas filled into the reactor at a pressure of 2.4 MPa; the co-catalyst is composed of ferrous chloride and magnesium sulfate, wherein the mass ratio of ferrous chloride to magnesium sulfate is 1:1.

25.

3. The formulation of high-purity oleic acid according to claim 1, characterized in that, The oleic acid C18:1 content prepared according to the above formula is ≥98%.

4. A method for preparing high-purity oleic acid, characterized in that, Includes the following steps: 1) Semi-hydrogenation process: Using 1000 parts of soybean oleic acid as raw material, under the action of 5-20 parts of Johnson Matthey's 9932 type hydrogenation nickel catalyst and 1.5-10 parts of co-catalyst, it reacts with hydrogen under high temperature and high pressure conditions. After the reaction is completed, it is cooled and filtered to obtain semi-hydrogenated soybean oleic acid. 2) Crystallization and centrifugation process: After cooling and crystallizing, semi-hydrogenated soybean oleic acid is centrifuged to separate the solid and liquid phases. The liquid phase is then separated by multiple crystallization processes to obtain high-purity oleic acid.

5. The method for preparing high-purity oleic acid according to claim 4, characterized in that, The soybean oleic acid contains ≤35% C18-1 (oleic acid), ≤55% C18-2 (linoleic acid), and 10.89% saturated fatty acids.

6. The method for preparing high-purity oleic acid according to claim 4, characterized in that, In the semi-hydrogenation process, the purity of hydrogen is ≥99.9%, the reaction temperature is 180-210℃, the reaction pressure is 1.6-2.8 MPa, and the reaction time is 1-2 hours.

7. The method for preparing high-purity oleic acid according to claim 4, characterized in that, The cooling crystallization operation method in the crystallization centrifugation process includes the following steps: Step 1, Homogenization of raw materials: Temperature: 50℃, stirring speed: 150r / min, holding time: 15min; Step 2, temperature: 25℃, stirring speed: 30r / min, holding time: 120min; Step 3, temperature: 20℃, stirring speed: 30r / min, holding time: 120min; Step 4: Temperature: 15℃, stirring speed: 25r / min, holding time: 60min; Step 5, crystal growth: Temperature: 13.6℃, ​​stirring speed: 15r / min, holding time: 720min.

8. The method for preparing high-purity oleic acid according to claim 4, characterized in that, The temperature of the centrifugation step in the crystallization centrifugation process is 14±1℃, the centrifuge speed is 6000-7000r / min, and the centrifugation time is 120-180 seconds.

9. A method for preparing high-purity oleic acid according to claim 4, characterized in that, In the crystallization centrifugation process, the liquid phase is crystallized and separated multiple times to obtain high-purity oleic acid. The number of repetitions is ≤6 times, preferably 3-4 times, and the purity of the final product, high-purity oleic acid, is ≥98%.

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