Method for removing trace contaminants from vitamin e

Abstract

The present application relates to the technical field of vitamin E, and discloses a method for removing trace contaminants in vitamin E, which comprises the following steps: contacting a preheated mixture containing vitamin E with activated carbon to remove the trace contaminants in the mixture containing vitamin E, and obtaining a vitamin E product. The method can improve the removal rate of the trace contaminants in the mixture containing vitamin E. The method does not need to introduce a solvent, thereby saving the step of removing the solvent, and therefore has the advantages of simple operation, energy saving and equipment investment, and low operation cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vitamin E, in particular to a method for removing trace pollutants in vitamin E. BACKGROUND

[0002] Vitamin E is a fat-soluble vitamin, which is one of the most important antioxidants. It is soluble in fat and ethanol and other organic solvents, and is not soluble in water. It is stable to heat and acid, but not stable to alkali. It is not sensitive to heat, but the activity is significantly reduced when fried. The phenolic hydroxyl group on the benzene ring of vitamin E is acetylated, and the ester is hydrolyzed to a phenolic hydroxyl group to become a tocopherol.

[0003] Vitamin E can promote reproduction. It can promote the secretion of sex hormones, increase the activity and quantity of sperm in men, and increase the concentration of female sex hormones in women, thereby improving fertility and preventing miscarriage. When vitamin E is deficient, testicular atrophy and epithelial cell degeneration occur, and abnormal pregnancy occurs. In clinical practice, vitamin E is often used to treat threatened abortion and habitual abortion. In addition, it is also helpful for the prevention and treatment of male infertility. Other functions include protecting T lymphocytes, protecting red blood cells, inhibiting platelet aggregation to reduce the risk of myocardial infarction and cerebral infarction. It also has good effects on burns, frostbite, capillary bleeding, menopausal syndrome, and beauty. It is also found that vitamin E can inhibit the peroxidation of lipids in the lens of the eye, dilate peripheral blood vessels, and improve blood circulation.

[0004] Natural vitamin E is extracted from various natural substances, and the raw material sources are extensive. After separation and extraction, there are still trace amounts of pollutants such as pesticide residues and toxins. Pesticide residues and toxin residues in food or drugs can seriously harm human health. With the tightening of national pesticide residue and toxin testing, pesticide residue and toxin residue in natural vitamin E has become an urgent problem that needs to be solved in the entire industry.

[0005] Natural vitamin E is generally separated and extracted from deodorized distillate (DD oil). Because the types of raw materials are more, there are various trace amounts of pollutants remaining. The existing technology removes pesticide residues and toxins by extraction or resin adsorption separation. The cost is high, a third solvent needs to be introduced or the operation is complex, and the pollutants cannot be completely removed. SUMMARY

[0006] The purpose of the present application is to overcome the problem of trace amounts of pollutants remaining in vitamin E products in the prior art, and to provide a method for removing trace amounts of pollutants in vitamin E.

[0007] The inventors of the present application found in the research process that, the mixture containing vitamin E is preheated first, and then contacted with activated carbon, not only can effectively remove trace contaminants in the mixture containing vitamin E, but also avoids the introduction of solvent, and simplifies the operation process. In order to achieve the above purpose, the present application provides a method for removing trace contaminants in vitamin E, which comprises: contacting the preheated mixture containing vitamin E with activated carbon to remove trace contaminants in the mixture containing vitamin E, and obtaining vitamin E product.

[0008] The method of the present application can improve the removal rate of trace contaminants in the mixture containing vitamin E. The method of the present application does not need to introduce solvent, so that the step of removing solvent is saved, and therefore the method of the present application has the advantages of simple operation, saving energy and equipment investment, and low running cost.

[0009] Preferably, the present application can further improve the removal rate of trace contaminants by preheating the mixture containing vitamin E to a specific temperature and combining with activated carbon having a specific structure. DETAILED DESCRIPTION

[0010] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The endpoints of the ranges and any values should be understood to be approximate, and in the context of the description, the approximation is based on the normal practice of those skilled in the art, using typical measuring equipment. Any numerical value, however, can be exact, depending on the desired information to be disclosed. Any numerical value, however, can be exact, depending on the desired information to be disclosed. For values which are deemed to be approximations, it is required that the numerical values be presented in a form which conveys the required precision.

[0011] The present application provides a method for removing trace contaminants in vitamin E, which comprises: contacting the preheated mixture containing vitamin E with activated carbon to remove trace contaminants in the mixture containing vitamin E, and obtaining vitamin E product.

[0012] According to the present application, the mixture containing vitamin E can be prepared and separated by conventional preparation method in the art, preferably, the content of vitamin E in the mixture containing vitamin E is 5-99 wt% (for example, 5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 90 wt%, 99 wt%, and the range formed by any two of the above), preferably 30-70 wt%.

[0013] According to the present application, preferably, the other main components in the vitamin E-containing mixture include at least one of glycerol, unsaturated fatty acid, methyl ester, ethyl ester, glyceride, squalene, sterol and sterol ester. In the present application, it is understood that the other main components refer to substances other than vitamin E, and the substances account for more than 0.5% by weight in the vitamin E-containing mixture.

[0014] According to the present application, preferably, the content of sterol in the vitamin E-containing mixture is 15-30% by weight (for example, 15%, 17%, 19%, 21%, 23%, 25%, 27%, 29%, 30%, and the range formed by any two of the above).

[0015] According to the present application, preferably, the content of glycerol in the vitamin E-containing mixture is 1-10% by weight (for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, and the range formed by any two of the above).

[0016] According to the present application, preferably, the content of methyl ester in the vitamin E-containing mixture is 1-5% by weight (for example, 1%, 2%, 3%, 4%, 5%, and the range formed by any two of the above).

[0017] According to the present application, preferably, the content of unsaturated fatty acid in the vitamin E-containing mixture is 2-10% by weight (for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, and the range formed by any two of the above).

[0018] According to the present application, preferably, the content of squalene in the vitamin E product is 0.5-3% by weight (for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, and the range formed by any two of the above).

[0019] According to the present application, preferably, the content of glyceride in the vitamin E-containing mixture is 1-10% by weight (for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, and the range formed by any two of the above).

[0020] According to the present application, preferably, the trace contaminants include at least one of the pesticide residues and benzopyrene that can be detected by GB23200.113 and GB23200.121; preferably at least one of fipronil and its metabolites, procymidone, dioxin, tebuconazole, bifenthrin and benzopyrene.

[0021] According to the present application, preferably, the content of trace contaminants in the vitamin E-containing mixture is 0.01 to 2000 ppm, more preferably 0.02 to 1000 ppm. In the present application, "ppm" means weight concentration.

[0022] According to the present application, preferably, the content of fipronil and its metabolites in the vitamin E-containing mixture is 0.01 to 5 ppm by weight, the content of procymidone is 0.01 to 5 ppm by weight, the content of tebuconazole is 0.01 to 5 ppm by weight, the content of bifenthrin is 0.01 to 5 ppm by weight, and the content of benzopyrene is 0.001 to 2 ppm by weight.

[0023] According to the present application, in order to improve the removal rate of trace contaminants, preferably, the temperature of the preheating is 40 to 150°C (for example, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, and a range consisting of any two of the above).

[0024] According to the present application, preferably, the temperature of the contacting is 40 to 150°C (for example, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, and a range consisting of any two of the above), and the time is 0.5 to 20 h (for example, 0.5 h, 1 h, 2 h, 3 h, 4 h, 5 h, 10 h, 15 h, 20 h, and a range consisting of any two of the above).

[0025] According to the present application, preferably, the activated carbon is a powdered activated carbon having an average particle size of 20 to 500 mesh (for example, 20 mesh, 50 mesh, 100 mesh, 150 mesh, 200 mesh, 250 mesh, 300 mesh, 350 mesh, 400 mesh, 450 mesh, 500 mesh, and a range consisting of any two of the above), and a specific surface area of 500 to 3000 m 2 / g (500 m 2 / g, 1000 m 2 / g, 1500 m 2 / g, 2000 m 2 / g, 2500 m 2 / g, 3000 m 2 / g, and a range consisting of any two of the above). The use of the powdered activated carbon having the above can remove pesticide residues and aromatic ring residues in vitamin E.

[0026] In the present application, the mesh number indicates the number of mesh holes per square centimeter of area.

[0027] According to the present invention, preferably, the pH value of the powdered activated carbon is 1-13, more preferably 9-10.

[0028] According to the present invention, preferably, the methylene blue adsorption value of the powdered activated carbon is greater than 100 mg / g, more preferably 230-240 mg / g.

[0029] Limiting the pH value and methylene blue adsorption value of powdered activated carbon to the above range can ensure the adsorption effect of activated carbon.

[0030] According to the present invention, preferably, the contact method includes: mixing a preheated mixture containing vitamin E with powdered activated carbon, and then stirring and / or sonicating at 40-150°C for 0.5-8 hours.

[0031] According to the present invention, preferably, the stirring speed is 10-600 rpm (for example, 10 rpm, 100 rpm, 200 rpm, 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, 600 rpm, and any range of any two of the above).

[0032] According to the present invention, preferably, the frequency of the ultrasound is 10-500MHz (e.g., 10MHz, 100MHz, 200MHz, 250MHz, 300MHz, 350MHz, 400MHz, 450MHz, 500MHz, and any two of the above), and more preferably 300-400MHz.

[0033] According to the present invention, preferably, the weight ratio of the vitamin E-containing mixture to the powdered activated carbon is 10-1000:1 (e.g., 10:1, 80:1, 100:1, 120:1, 150:1, 200:1, 300:1, 400:1, 500:1, 600:1, 700:1, 800:1, 900:1, 1000:1, and any two of the above). More preferably, considering both cost and the removal rate of trace organic matter, the weight ratio of the vitamin E-containing mixture to the powdered activated carbon is 100-150:1.

[0034] According to the present invention, preferably, the activated carbon is granular activated carbon, wherein the average particle size of the granular activated carbon is 5-100 mesh, and the specific surface area is 300-1500 m². 2 / g, pore volume 0.15-0.9cm³ 3 / g.

[0035] According to the present invention, preferably, the pH value of the granular activated carbon is 2-13, more preferably 9-10.

[0036] According to the present application, preferably, the methylene blue adsorption value of the granular activated carbon is greater than 100 mg / g, more preferably 200-220 mg / g.

[0037] According to the present application, preferably, the contacting is performed by loading the granular activated carbon in a container to form a stationary phase, and then contacting the preheated vitamin E-containing mixture with the granular activated carbon. The type of the stationary container is not particularly limited, and can be a chromatographic column commonly used in the art, or other containers having an inlet and an outlet, as long as the vitamin E-containing mixture can be contacted with the granular activated carbon in the container.

[0038] According to the present application, preferably, the weight ratio of the vitamin E-containing mixture to the granular activated carbon is 5-500:1 (for example, 5:1, 5.5:1, 6:1, 7:1, 8:1, 100:1, 200:1, 300:1, 400:1, 500:1, and a range formed by any two of the above). More preferably, the weight ratio of the vitamin E-containing mixture to the granular activated carbon is 5-6:1, taking into account the cost and the removal rate of trace organic matter.

[0039] According to the present application, preferably, the temperature of the stationary phase is 40-150℃ (for example, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, and a range formed by any two of the above).

[0040] According to the present application, preferably, the residence time of the vitamin E-containing mixture in the stationary phase is 0.5-20 h.

[0041] In the present application, the stationary phase can be first soaked with anhydrous ethanol, and then the preheated vitamin E-containing mixture is introduced to gradually displace the anhydrous ethanol, so as to prevent the phenomenon of insufficient contact and air bubbles.

[0042] According to the present application, preferably, the method further comprises filtering the vitamin E-containing mixture after contacting with the activated carbon at 20-120℃ (preferably 50-100℃).

[0043] According to the present application, preferably, the filtering comprises a first filtering and a second filtering, the first filtering is at least one of filter paper or filter cloth; the second filtering is microfiltration; more preferably, the pore size of the microfiltration membrane used in the microfiltration is 0.2-80 μm, more preferably 0.22-50 μm.

[0044] According to a particularly preferred embodiment of the present application, the method for removing trace contaminants in vitamin E comprises: preheating the vitamin E-containing mixture to 85-90 DEG C, then adding activated carbon powder into the vitamin E-containing mixture and performing ultrasonic treatment at the preheating temperature; wherein the ultrasonic treatment is performed at a frequency of 400-450 MHz for 3-3.5 h, and the weight ratio of the vitamin E-containing mixture to the activated carbon powder is 80-100:1; the average particle size of the activated carbon powder is 200-210 mesh, the specific surface area of the activated carbon powder is 1100-1200 m 2 / g, the pH value is 9.5-10, and the methylene blue adsorption value is 235-240 mg / g.

[0045] According to a particularly preferred embodiment of the present application, the method for removing trace contaminants in vitamin E comprises: packing activated carbon particles in a chromatographic column to form an activated carbon column (stationary phase), and filling the activated carbon column with ethanol, then feeding the preheated vitamin E-containing mixture into the activated carbon column to gradually discharge the ethanol. In the method, the vitamin E-containing mixture stays in the activated carbon column for 4-4.5 h, and the temperature of the activated carbon column is kept at 90-95 DEG C during the staying process; the weight ratio of the vitamin E-containing mixture to the activated carbon particles is 5-5.5:1; the average particle size of the activated carbon particles is 40-45 mesh, the specific surface area of the activated carbon particles is 1050-1100 m 2 / g, the pore volume is 0.8-0.9 cm 3 / g, the pH value is 9.5-10, and the methylene blue adsorption value is 210-220 mg / g.

[0046] The present application also provides a method for detecting pesticide residues in vitamin E, which comprises steps (1), (2) and (3A), or steps (1), (2) and (3B):

[0047] (1) mixing the sample to be detected with water and an extraction agent to obtain a first mixture, then mixing the first mixture with a first dehydrating agent, sodium chloride and sodium citrate dihydrate to obtain a second mixture, and separating the second mixture to obtain a first extraction liquid;

[0048] (2) mixing the first extraction liquid with a second dehydrating agent, ethylenediamine-N-propylsilane and C18 reversed-phase silica gel to obtain a third mixture, and separating the third mixture to obtain a second extraction liquid;

[0049] (3A) extracting the second extraction liquid with a non-polar solvent of methyl cyanide for at least one time to obtain a third extraction liquid, then detecting the content of the pesticide in the third extraction liquid by liquid chromatography-mass spectrometry, and calculating the content of the pesticide in the sample to be detected;

[0050] (3B) drying the second extraction solution to obtain a dried product, the solvent content of the dried product being less than 10% by weight, dissolving the dried product in ethyl acetate, and then detecting the content of the pesticide in the ethyl acetate solution of the dried product by GC-MS, and calculating the content of the pesticide in the sample to be tested.

[0051] According to the present application, in order to improve the extraction rate of pesticide residues, preferably, in step (1), the amount of water used is 1-50 mL (for example, 1 mL, 2 mL, 4 mL, 5 mL, 7 mL, 9 mL, 10 mL, 13 mL, 15 mL, 18 mL, 20 mL, 30 mL, 40 mL, 50 mL, and a range consisting of any two of the above), more preferably 1-20 mL, per gram of sample to be tested.

[0052] According to the present application, in order to improve the extraction rate of pesticide residues, preferably, in step (1), the amount of methyl cyanide used is 1-50 mL (for example, 1 mL, 5 mL, 9 mL, 10 mL, 13 mL, 15 mL, 18 mL, 20 mL, 30 mL, 40 mL, 50 mL, and a range consisting of any two of the above), more preferably 1-20 mL, per gram of sample to be tested.

[0053] According to a particularly preferred embodiment of the present application, in step (1), the volume ratio of water to acetonitrile is 1:1-5, particularly preferably 1:1.5-3.

[0054] According to the present application, preferably, the extraction agent comprises at least one of methyl cyanide, C1-C4 monohydric alcohol (for example, methanol, ethanol, propanol, butanol, etc.), and acetone. Preferably, the extraction agent does not contain a detectable amount of acid (for example, formic acid, acetic acid, propionic acid, etc.).

[0055] According to the present application, preferably, in step (1), the weight ratio of the sample to be tested to the first dehydrating agent, sodium chloride, and sodium hydrogen citrate hydrate is 1:1-20:0.5-20:0.5-20, more preferably 1:1-10:0.5-10:0.5-10, and further preferably 1:4-5:0.5-1:0.5-1. Limiting the amount of the first dehydrating agent, sodium chloride, and sodium hydrogen citrate hydrate to the above range can improve the extraction rate of pesticide residues.

[0056] The present application can effectively improve the extraction rate of pesticide residues by using the specific combination of water and methyl cyanide in step (1) and the specific combination of the first dehydrating agent, sodium chloride, and sodium hydrogen citrate hydrate to extract pesticide residues in vitamin E.

[0057] According to the present application, preferably, in step (1), the conditions of the first mixing and the second mixing each independently include a temperature of 15-40°C and a time of 1-60 min.

[0058] In order to make the mixing more uniform, generally, ceramic homogenizers can be added to the mixing system, and in the preferred embodiment of the present application, ceramic homogenizers are added in the first mixing process.

[0059] According to the present application, preferably, the first mixing and the second mixing are each independently at least one of shaking, ultrasonic, stirring and vortex mixing.

[0060] According to the present application, preferably, the first dehydrating agent and the second dehydrating agent are each independently at least one of anhydrous magnesium sulfate, anhydrous calcium chloride and silica gel.

[0061] According to the present application, preferably, in step (2), the amount of the second dehydrating agent is 50-1000 mg (for example, 50 mg, 80 mg, 100 mg, 120 mg, 140 mg, 160 mg, 180 mg, 200 mg, 300 mg, 400 mg, 500 mg, 800 mg, 1000 mg, and a range between any two of the above), more preferably 80-500 mg, and further preferably 80-180 mg, per milliliter of the first extraction solution; the amount of ethylenediamine-N-propylsilane is 10-500 mg (for example, 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, 70 mg, 80 mg, 100 mg, 200 mg, 300 mg, 400 mg, 500 mg, and a range between any two of the above), more preferably 20-200 mg, and further preferably 20-70 mg; and the amount of C18 reversed-phase silica gel is 10-500 mg (for example, 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, 70 mg, 80 mg, 100 mg, 200 mg, 300 mg, 400 mg, 500 mg, and a range between any two of the above), more preferably 20-200 mg, and further preferably 20-70 mg.

[0062] According to the present application, preferably, the average particle size of the C18 reversed-phase silica gel is 2-200 μm, more preferably 40-60 μm, and the average pore size is 0.5-50 nm, more preferably 1-5 nm. The C18 reversed-phase silica gel with the specific parameter range of the present application has excellent stability and repeatability, and has the characteristics of high selectivity and high separation.

[0063] According to the present application, preferably, the conditions of the third mixing include a temperature of 15-40 °C and a time of 1-30 min.

[0064] According to the present application, preferably, the third mixing is at least one of vortexing, shaking, ultrasonic and stirring.

[0065] According to the present application, preferably, in step (3A), the volume ratio of methyl cyanide to non-polar solvent is 1:10-500, more preferably 1:10-300. Further preferably, in step (3A), the non-polar solvent of methyl cyanide is a non-polar solvent saturated with methyl cyanide.

[0066] According to the present application, preferably, the total amount of methyl cyanide and non-polar solvent is 0.1-20 mL (for example, 0.1 mL, 0.5 mL, 0.8 mL, 1 mL, 1.2 mL, 1.5 mL, 1.8 mL, 2 mL, 5 mL, 10 mL, 20 mL, and the range consisting of any two of the above) per mL of the second extraction liquid, more preferably 0.5-10 mL.

[0067] According to the present application, preferably, the non-polar solvent is at least one of n-pentane, n-hexane, n-heptane, and petroleum ether.

[0068] According to the present application, preferably, in step (3A), the number of extractions is 1-5, preferably 2-3. More preferably, the extraction process comprises: dividing the methyl cyanide-saturated non-polar solvent into several portions, mixing the second extraction liquid with the first portion of methyl cyanide-saturated non-polar solvent to obtain an extraction phase by shaking, and then mixing the remaining portions of methyl cyanide-saturated non-polar solvent with the extraction phase in turn to obtain a methyl cyanide phase by shaking.

[0069] According to the present application, preferably, in step (3A), the extraction process comprises: dividing the methyl cyanide-saturated non-polar solvent into 1-5 equal portions, filtering the second extraction liquid through a polytetrafluoroethylene filter to obtain a filtrate, mixing the filtrate with the first portion of methyl cyanide-saturated non-polar solvent to obtain a first extraction methyl cyanide phase by shaking and standing to separate into layers, and discarding the non-polar solvent layer (discarding the upper layer); and then extracting the first extraction methyl cyanide phase with the remaining portions of methyl cyanide-saturated non-polar solvent to obtain the final methyl cyanide phase.

[0070] According to the present application, preferably, the liquid chromatograph used in the liquid chromatography-mass spectrometry can be a commonly used chromatographic column in the art, preferably, the chromatographic column is a waters-100mm c18 BEH C18 1.7μm MVK.

[0071] According to the present application, preferably, the detector of the liquid chromatograph used in the liquid chromatography-mass spectrometry can be a commonly used detector in the art, preferably, the detector is an ultraviolet detector.

[0072] According to the present application, preferably, the operating temperature of the liquid chromatograph used in the liquid chromatography-mass spectrometry is 15-45℃.

[0073] According to the present application, preferably, the liquid chromatograph of the liquid chromatography-mass spectrometry adopts a mobile phase of a methanol aqueous solution, and more preferably, the elution gradient of the mobile phase is 20% by volume (0-0.5 min), 30% by volume (0.5-1 min), 63% by volume (1-2.2 min), 75% by volume (2.2-2.5 min), 95% by volume (2.5-3 min), 95% by volume (3-3.5 min), and 20% by volume (3.5-4 min). Herein, 20% by volume (0-0.5 min) means that the mobile phase is a methanol aqueous solution with a volume concentration of 20%, and elution is performed for 0-0.5 min.

[0074] According to the present application, preferably, the flow rate of the mobile phase of the liquid chromatograph is 0.1-1 mL / min.

[0075] According to the present application, preferably, the injection amount of the liquid chromatograph is 0.5-5 μL.

[0076] According to the present application, preferably, in step (3B), the amount of ethyl acetate used is 0.5-10 mL per milliliter of the second extraction liquid.

[0077] According to the present application, the chromatographic column of the gas chromatograph used in the gas chromatography-mass spectrometry detection can be a chromatographic column commonly used in the art, and preferably, the chromatographic column of the gas chromatograph used in the gas chromatography-mass spectrometry detection is an Agilent CP914 with a specification of 15 m x 250 μm x 0.25 μm.

[0078] According to the present application, the temperature programming process of the chromatographic column of the gas chromatograph used in the gas chromatography-mass spectrometry detection can be a temperature programming process commonly used in the art, and in order to further improve the accuracy of detection, preferably, the temperature programming process of the chromatographic column of the gas chromatograph comprises: maintaining at 25-40℃ for 1-15 min, increasing the temperature to 90-150℃ at a rate of 20-60℃ / min and maintaining for 0-10 min, increasing the temperature to 200-270℃ at a rate of 0-10℃ / min, and increasing the temperature to 240-330℃ at a rate of 2-20℃ / min.

[0079] According to the present application, preferably, the flow rate of the carrier gas of the gas chromatograph is 0.1-50 mL / min, and the carrier gas is nitrogen and / or an inert gas; more preferably, the inert gas is at least one of helium, neon, argon, and krypton.

[0080] According to the present application, preferably, the injection amount of the gas chromatography-mass spectrometry detection is 0.1-10 μL. The injection mode is splitless injection.

[0081] According to the present application, preferably, the detection conditions of the mass spectrometry in the liquid chromatography-mass spectrometry or the gas chromatography-mass spectrometry comprise: an ion source mode of EI ion source and an ion monitoring mode of MRM.

[0082] According to a particularly preferred embodiment of the present invention, a method for detecting pesticide residues in vitamin E includes:

[0083] (1) Place the sample to be tested in a plastic tube, then add water, methyl cyanide and ceramic homogenizer, and shake vigorously for 15-20 min to obtain the first mixture. Then add anhydrous magnesium sulfate, sodium chloride and disodium hydrogen citrate hydrate to the first mixture, shake vigorously for 1-3 min, and centrifuge at 5000-6000 r / min for 5-10 min to obtain the first extract. The amount of water used is 5-6 mL and the amount of methyl cyanide is 10-15 mL per gram of sample to be tested; the weight ratio of the sample to anhydrous magnesium sulfate, sodium chloride and disodium hydrogen citrate hydrate is 1:4-4.5:0.5-1:0.5-1.

[0084] (2) The first extract is mixed with anhydrous magnesium sulfate, C18 reversed-phase silica gel and ethylenediamine-N-propylsilane in a plastic centrifuge tube and vortexed for 1-3 min. Then, it is centrifuged at 5000-6000 r / min for 1-5 min to obtain the second extract. The amount of anhydrous magnesium sulfate, ethylenediamine-N-propylsilane and C18 reversed-phase silica gel is 145-150 mg and 50-55 mg respectively, relative to each milliliter of the first extract.

[0085] (3A) Divide methyl cyanide-saturated n-hexane into two equal portions. Filter the second extract through a polytetrafluoroethylene (PTFE) membrane to obtain the filtrate. Mix the filtrate with the first portion of methyl cyanide-saturated n-hexane, shake for 3-5 minutes, allow to stand and separate into layers, discard the n-hexane layer (and the upper layer) to obtain the first methyl cyanide extract phase. Then mix the first methyl cyanide extract phase with the second portion of methyl cyanide-saturated n-hexane, shake for 3-5 minutes, allow to stand and separate into layers, discard the n-hexane layer (and the upper layer) to obtain the second methyl cyanide extract phase. The total amount of methyl cyanide-saturated n-hexane used is 0.8-1 mL per milliliter of the second extract. Then, use liquid chromatography-mass spectrometry (LC-MS) to determine the pesticide content in the third extract and calculate the pesticide content in the sample.

[0086] (3B) The second extract was dried to obtain a dried product. The solvent content in the dried product was less than 3% by weight. The dried product was dissolved in ethyl acetate. Then, the pesticide content in the ethyl acetate solution of the dried product was detected by gas chromatography-mass spectrometry (GC-MS), and the pesticide content in the sample to be tested was calculated.

[0087] The present invention will be described in detail below through embodiments. In the following embodiments,

[0088] The method for testing the content of the main components in a mixture containing vitamin E is liquid chromatography.

[0089] Method for testing benzopyrene in vitamin E-containing mixture: GB5009.27-2016.

[0090] Method for testing fipronil and its metabolites in vitamin E-containing mixture (liquid chromatography-mass spectrometry):

[0091] Process for making external standard curve of liquid chromatography-mass spectrometry: the standard sample is a mixed standard of fipronil and its metabolites, and the concentration gradient of the standard curve is 0.02, 0.06, 0.1, 0.14, 0.18, 0.22, 0.3, and 0.5 ppm. Then, analysis is performed under the liquid chromatography conditions, and linear regression is performed with the concentration as the abscissa and the peak area as the ordinate to obtain a linear equation (Y = 112161x - 3214) and a correlation coefficient (R 2 = 0.9998).

[0092] (1) 1 g of the sample to be tested is placed in a 50 mL plastic tube, and then water, methyl cyanide, and 1 ceramic homogenate are added, and the mixture is shaken vigorously for 15 min to obtain a first mixture. Then, anhydrous magnesium sulfate, sodium chloride, and citric acid disodium hydrate are added to the first mixture, and the mixture is shaken vigorously for 3 min, and then centrifuged at 5000 r / min for 5 min to obtain a first extract. Among them, the amount of water used is 5 mL per gram of the sample to be tested, and the amount of methyl cyanide used is 10 mL; the weight ratio of the sample to be tested to anhydrous magnesium sulfate, sodium chloride, and citric acid disodium hydrate is 1:4:1:1.

[0093] (2) The first extract, anhydrous magnesium sulfate, C18 reversed-phase silica gel, and ethylenediamine-N-propylsilane are placed in a plastic centrifuge tube and vortexed for 3 min, and then centrifuged at 5000 r / min for 5 min to obtain a second extract. Among them, the amount of anhydrous magnesium sulfate used is 150 mg per milliliter of the first extract, the amount of ethylenediamine-N-propylsilane used is 50 mg, and the amount of C18 reversed-phase silica gel used is 50 mg.

[0094] (3) The methyl cyanide-saturated n-hexane is divided into two equal parts, the second extract is filtered through a polytetrafluoroethylene filter membrane to obtain a filtrate, the filtrate is mixed with the first part of the methyl cyanide-saturated n-hexane, shaken for 3 min, and then allowed to separate into layers, and the n-hexane layer is discarded (the upper layer is discarded) to obtain a first methyl cyanide extract. Then, the first methyl cyanide extract is mixed with the second part of the methyl cyanide-saturated n-hexane, shaken for 3 min, and then allowed to separate into layers, and the n-hexane layer is discarded (the upper layer is discarded) to obtain a second methyl cyanide extract. Among them, the total amount of methyl cyanide-saturated n-hexane used is 1 mL per milliliter of the second extract.

[0095] The content of the pesticide in the second methyl cyanide extract is detected by liquid chromatography-mass spectrometry, and the content of the pesticide in the sample to be tested is calculated. Among them, the test conditions of the liquid chromatography-mass spectrometry are as follows: the chromatographic column is a waters-100mm c18 BEHC18 1.7 μm MVK, the running temperature is 40℃, the mobile phase is methanol aqueous solution, the elution gradient is 20% (0 min), 30% (0.5 min), 63% (1 min), 75% (2.2 min), 95% (2.5 min), 95% (3 min), 20% (3.5 min), the flow rate is 0.4 mL / min, the injection volume is 1 μL. The mass spectrometry condition: the ion source mode is EI ion source, the ion monitoring mode is MRM.

[0096] The peak area of each pesticide component in the obtained chromatogram is integrated, and the peak area is brought into the external standard curve to calculate the content of fipronil and its metabolites in the sample to be tested.

[0097] The test method (GC-MS) for the contents of procymidone, fipronil, tebuconazole and bifenthrin in the vitamin E-containing mixture is as follows:

[0098] The preparation process of the external standard curve of GC-MS is as follows: the standard sample is a mixed standard of procymidone, fipronil, tebuconazole and bifenthrin, and the concentration gradient of the standard curve is 0.02, 0.06, 0.1, 0.14, 0.18, 0.22, 0.3, 0.5 ppm. Then, analysis is performed under the condition of gas chromatography, and linear regression is performed with the concentration as the abscissa and the peak area as the ordinate to obtain a linear equation (Y = 117420x - 3406) and a correlation coefficient (R 2 = 0.9999).

[0099] Steps (1) and (2) are the same as steps (1) and (2) of LC-MS.

[0100] (3) The second extraction liquid is dried to obtain a dry product, the solvent content in the dry product is less than 3% by weight, the dry product is dissolved in ethyl acetate, and then the content of pesticides in the ethyl acetate solution of the dry product is detected by GC-MS, and the content of pesticides in the sample to be tested is calculated. Among them, the amount of ethyl acetate used is 1 ml relative to each milliliter of the second extraction liquid.

[0101] The test conditions of GC-MS are as follows: the chromatographic column of the gas chromatograph is Agilent CP9148, and the specifications of the two chromatographic columns are 15 m x 250 μm x 0.25 μm connected in series; the program temperature process of the chromatographic column of the gas chromatograph includes: keeping at 40℃ for 1 min, increasing the temperature to 120℃ at a rate of 40℃ / min, keeping at 120℃ for 1 min, increasing the temperature to 240℃ at a rate of 5℃ / min, and increasing the temperature to 300℃ at a rate of 12℃ / min; the flow rate of the carrier gas of the gas chromatograph is 2 mL / min, and the carrier gas is nitrogen; the injection volume for chromatographic analysis is 1 μL, and there is no split. The mass spectrometry condition: the ion source mode is EI ion source, and the ion monitoring mode is MRM.

[0102] The peak area of each pesticide component in the obtained chromatogram is integrated, and the peak area is brought into the external standard curve to calculate the content of each pesticide component in the sample to be tested.

[0103] The vitamin E-containing mixture is a product obtained after DD oil separation and extraction, and the names and contents of the main components and trace organic matters of the vitamin E-containing mixture are shown in Table 1:

[0104] Table 1

[0105] Main components Content (% by weight) Vitamin E 50 Sterols 25 Glycerol 5 Methyl esters 3 Unsaturated fatty acids 7 Squalene 2 Mono- / di- / triglycerides 8 Trace organic substances Content (ppm) Fipronil and its metabolites 0.2 Procymidone 0.2 Tebuthiuron 1 Bifenthrin 0.2 Benzopyrene 0.4

[0106] Example 1

[0107] The vitamin E-containing mixture is preheated to 85°C, and then activated carbon powder is added to the vitamin E-containing mixture, and ultrasonic treatment is carried out at the preheating temperature; wherein the ultrasonic treatment conditions include: a frequency of 400MHz, a time of 3h; the weight ratio of the vitamin E-containing mixture to the activated carbon powder is 100:1; the average particle size of the activated carbon powder is 200 mesh, the specific surface area is 1100m 2 / g, the pH value is 10, and the methylene blue adsorption value is 240mg / g.

[0108] The product after ultrasonic treatment is subjected to filter cloth filtration and microfiltration, and cooled to room temperature to obtain a vitamin E product; wherein the filtration and microfiltration temperature is 85°C, and the pore size of the microfiltration membrane used in the microfiltration is 0.45μm. The names and contents of the trace organic matters in the vitamin E product are shown in Table 2.

[0109] Example 2

[0110] The vitamin E-containing mixture is preheated to 80°C, and then activated carbon powder is added to the vitamin E-containing mixture, and ultrasonic treatment is carried out at the preheating temperature; wherein the ultrasonic treatment conditions include: a frequency of 350MHz, a time of 2.5h; the weight ratio of the vitamin E-containing mixture to the activated carbon powder is 150:1; the average particle size of the activated carbon powder is 220 mesh, the specific surface area is 1050m 2 / g, the pH value is 9, and the methylene blue adsorption value is 230mg / g.

[0111] The product after ultrasonic treatment is subjected to filter paper filtration and microfiltration, and cooled to room temperature to obtain a vitamin E product; wherein the filtration and microfiltration temperature is 80°C, and the pore size of the microfiltration membrane used in the microfiltration is 0.8μm. The names and contents of the trace organic matters in the vitamin E product are shown in Table 2.

[0112] Example 3

[0113] According to the method of Example 1, except that the ultrasonic treatment is replaced by stirring, the stirring speed is 400rpm, and the time is 3h.

[0114] Example 4

[0115] The activated carbon particles were packed in a chromatographic column to form an activated carbon column (stationary phase), and the activated carbon column was filled with ethanol, and then the mixture containing vitamin E preheated to 90°C was fed into the activated carbon column to gradually discharge the ethanol. In the process, the mixture containing vitamin E was kept in the activated carbon column for 4 hours, and the temperature of the activated carbon column was kept at 90°C during the residence; the weight ratio of the mixture containing vitamin E to the activated carbon particles was 5:1; the average particle size of the activated carbon particles was 40 mesh, the specific surface area was 1050 m 2 / g, the pore volume was 0.8 cm 3 / g, the pH value was 10, and the methylene blue adsorption value was 220 mg / g.

[0116] The mixture containing vitamin E discharged from the activated carbon column was micro-filtered to obtain a vitamin E product; in the process, the temperature of the filtration and micro-filtration was 90°C, and the pore size of the micro-filtration membrane used in the micro-filtration was 0.8 μm. The names and contents of the trace organic substances in the vitamin E product are shown in Table 2.

[0117] Example 5

[0118] The activated carbon particles were packed in a chromatographic column to form an activated carbon column (stationary phase), and the activated carbon column was filled with ethanol, and then the mixture containing vitamin E preheated to 85°C was fed into the activated carbon column to gradually discharge the ethanol. In the process, the mixture containing vitamin E was kept in the activated carbon column for 3 hours, and the temperature of the activated carbon column was kept at 85°C during the residence; the weight ratio of the mixture containing vitamin E to the activated carbon particles was 6:1; the average particle size of the activated carbon particles was 30 mesh, the specific surface area was 1000 m 2 / g, the pore volume was 0.7 cm 3 / g, the pH value was 9, and the methylene blue adsorption value was 200 mg / g.

[0119] The mixture containing vitamin E discharged from the activated carbon column was filtered with cloth to obtain a vitamin E product; in the process, the temperature of the filtration was 85°C. The names and contents of the trace organic substances in the vitamin E product are shown in Table 2.

[0120] Example 6

[0121] The method of Example 1 was followed, except that the preheating temperature was 120°C.

[0122] Example 7

[0123] The method of Example 1 was followed, except that the preheating temperature was 50°C.

[0124] Example 8

[0125] The procedure of Example 1 was followed except that the average particle size of the activated carbon powder was 150 mesh and the specific surface area was 950 m2 / g. 2 / g.

[0126] Example 9

[0127] The procedure of Example 1 was followed except that the pH of the activated carbon powder was 7.

[0128] Example 10

[0129] The procedure of Example 1 was followed except that the frequency of the ultrasound was 200 MHz.

[0130] Example 11

[0131] The procedure of Example 1 was followed except that the process of microfiltration was not included.

[0132] Example 12

[0133] The procedure of Example 4 was followed except that the temperature of the preheating was 150°C.

[0134] Example 13

[0135] The procedure of Example 4 was followed except that the temperature of the preheating was 50°C.

[0136] Example 14

[0137] The procedure of Example 4 was followed except that the average particle size of the activated carbon particles was 10 mesh and the specific surface area was 850 m2 / g. 2 / g.

[0138] Example 15

[0139] The procedure of Example 4 was followed except that the pH of the activated carbon particles was 8.

[0140] Comparative Example 1

[0141] The procedure of Example 1 was followed except that the preheating treatment was not performed on the vitamin E-containing mixture.

[0142] Table 2

[0143]

[0144]

[0145] As can be seen from the results of Table 1, compared with Comparative Example 1, the examples provided by the present application can effectively remove trace organic matter and improve the removal rate of trace organic matter. Preferably, compared with Examples 6-11, Example 1 of the present application can further improve the removal rate of trace organic matter. Similarly, compared with Examples 12-15, Example 4 of the present application can further improve the removal rate of trace organic matter.

[0146] In addition, the method of the present application does not require the introduction of a solvent, thereby eliminating the step of removing the solvent, and thus the method of the present application has the advantages of simple operation, energy saving and equipment investment, low operating cost, and further improved removal rate of trace organic matter.

[0147] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A method for removing trace contaminants from vitamin E, characterized in that, The method includes: contacting a preheated mixture containing vitamin E with activated carbon to remove trace contaminants from the mixture containing vitamin E, thereby obtaining a vitamin E product; The preheating temperature is 80-100℃; the contact temperature is 80-100℃; and the specific surface area of ​​the activated carbon is 1000-2000 m². 2 / g; the pH value of the activated carbon is 9-10.

2. The method according to claim 1, wherein, The vitamin E content in the mixture is 5-99% by weight. And / or, other major components of the vitamin E-containing mixture include at least one of glycerol, unsaturated fatty acids, methyl esters, ethyl esters, glycerides, squalene, sterols, and sterol esters.

3. The method according to claim 1, wherein, The contact time is 0.5-20 hours.

4. The method according to claim 1, wherein, The activated carbon is powdered activated carbon, and the average particle size of the powdered activated carbon is 20-500 mesh; And / or, the methylene blue adsorption value of the powdered activated carbon is greater than 100 mg / g.

5. The method according to claim 4, wherein, The contact method includes: mixing the preheated vitamin E-containing mixture with powdered activated carbon, and then stirring and / or sonicating at 80-100°C for 0.5-8 hours.

6. The method according to claim 5, wherein, The stirring speed is 10-600 rpm; And / or, the frequency of the ultrasound is 10-500MHz; And / or, the weight ratio of the vitamin E-containing mixture to powdered activated carbon is 10-1000:

1.

7. The method according to claim 1, wherein, The activated carbon is granular activated carbon, with an average particle size of 5-100 mesh and a pore volume of 0.15-0.9 cm³. 3 / g; And / or, the alanine adsorption value of the granular activated carbon is greater than 100 mg / g.

8. The method according to claim 7, wherein, The contact method includes: filling granular activated carbon into a container to form a stationary phase, and then contacting the preheated vitamin E-containing mixture with the granular activated carbon.

9. The method according to claim 8, wherein, The weight ratio of the vitamin E-containing mixture to granular activated carbon is 5-500:1; And / or, the temperature of the stationary phase is 40-150°C; And / or, the residence time of the vitamin E-containing mixture in the stationary phase is 0.5-20 h.

10. The method according to any one of claims 1-9, wherein, The method further includes: filtering the mixture containing vitamin E after contact with activated carbon at 20-120°C; The filtration includes a first filtration and a second filtration, wherein the first filtration is at least one of filter paper or filter cloth filtration; and the second filtration is microfiltration.

11. The method according to claim 10, wherein, The microfiltration process uses a microfiltration membrane with a pore size of 0.2-80 μm.

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