Process for preparing colorless camellia oil by silica gel chromatography

Abstract

The present application relates to camellia oil high-value processing technology and application field, specifically relates to a kind of process for preparing colorless camellia oil by silica gel chromatography.It is characterized in that: different silica gel adsorbent and activated carbon are pretreated according to specific combination to build chromatographic column, to achieve the purpose of preparing cosmetic colorless camellia oil from cold-pressed camellia oil, degumming and deacidification camellia oil, refined camellia oil or edible camellia oil at room temperature.The present application effectively avoids the technical defects of high temperature and repeated physical adsorption decolorization in traditional process, has the advantages of raw material safety and environmental protection, simple process, significant energy saving, high preparation efficiency;Using adsorption chromatography to remove pigment components, the quality of cosmetic grade colorless camellia oil is achieved, a new preparation path of colorless camellia oil is opened up, which can provide technical support for the high-quality development of camellia oil industry.

Description

Technical Field

[0001] This invention relates to the field of high-value processing technology and application of camellia oil, specifically a process for preparing colorless camellia oil by silica gel chromatography. Background Technology

[0002] Camellia oil is a natural woody plant oil extracted from the seeds of the camellia tree, and it is a unique edible oil in my country. Its nutritional value is outstanding, earning it the reputation of "Oriental olive oil." Camellia oil is rich in monounsaturated fatty acids, with oleic acid content reaching 68%-87% and linoleic acid accounting for 3.8%-14%. Its monounsaturated fatty acid content is far higher than most vegetable oils, and its quality indicators are comparable to olive oil. At the same time, camellia oil is also rich in trace bioactive components such as tocopherols, squalene, phytosterols, and tea polyphenols, giving it multiple beneficial properties including antioxidant, antibacterial, anti-inflammatory, lipid-lowering, and skin-beautifying effects. Based on these properties, camellia oil not only serves as a high-end edible oil but also shows broad application prospects in cosmetics, medicine, and other fields.

[0003] To meet the stringent requirements of high purity, low impurities, and high safety for cosmetic and medical oils, raw camellia oil, after initial processing into refined or commercial camellia oil, still needs to undergo deep decolorization to achieve a clear and transparent state in order to meet relevant application requirements. Existing methods for preparing colorless camellia oil include: Chinese Invention Patent Publication No. CN112831371A discloses a method for preparing high-quality colorless camellia oil, but this method requires repeating the adsorption and decolorization steps three times under heating and a certain degree of vacuum, which consumes a lot of energy and materials and has low production efficiency; Chinese Invention Patent Publication No. CN107746745A discloses a method for preparing woody plant-based colorless oil at low temperature, but this method uses petroleum ether to dilute the oil, which can easily cause solvent residue in subsequent processing; Chinese Invention Patent Publication No. CN106635412B discloses an oil processing and separation method, but this method uses short-path molecular distillation to separate pigment components to prepare colorless camellia oil. High temperature may destroy the heat-sensitive active ingredients in the camellia oil, such as vitamin E, and the conditions are harsh, energy consumption is high, and there are many steps, resulting in low production efficiency.

[0004] Currently, the production of colorless camellia oil both domestically and internationally is still in its initial stage. Therefore, this invention aims to provide a simple process for preparing colorless camellia oil for cosmetic use, broaden the application fields of camellia oil, improve the economic benefits brought by camellia oil, and provide new ideas for the high-quality development of camellia oil. Summary of the Invention

[0005] The purpose of this invention is to provide a process for preparing colorless camellia oil by silica gel chromatography. This method can solve the problems of complex procedures, harsh production conditions, high energy consumption, and solvent residue in the oil in the current preparation process. It can quickly prepare colorless camellia oil for cosmetics without changing the camellia oil refining and processing production line.

[0006] The technical solution adopted by the present invention to solve the above-mentioned problems is as follows:

[0007] The process for preparing colorless camellia oil by silica gel chromatography is characterized by the following steps:

[0008] Step (1), pretreatment of packing material: The sulfonic acid silica gel adsorbent is soaked in ultrapure water, methanol and n-hexane with a volume equivalent to 3 to 8 times its mass for 3 to 24 hours and then dried to constant weight to obtain sulfonic acid silica gel adsorbent A;

[0009] Step (2), column packing: The sulfonic acid silica gel adsorbent A and activated carbon or amino silica gel adsorbent obtained in step (1) are packed into the column in the order of sulfonic acid silica gel adsorbent A-amino silica gel adsorbent-activated carbon or sulfonic acid silica gel adsorbent A-activated carbon and a certain oil weight ratio, and then compacted to obtain the column.

[0010] Step (3), tea oil decolorization: At room temperature, the raw camellia oil is poured into the chromatography column obtained in step (2), filtered and the eluent is collected to obtain colorless camellia oil.

[0011] In this invention, ultrapure water soaking is mainly used to remove residual acidic substances in the adsorbent, preventing an increase in the acid value of the camellia oil after decolorization. Sulfonic acid-based silica gel adsorbents can specifically adsorb weak cationic pigments in camellia oil, while amino silica gel adsorbents can specifically adsorb polar and weak anionic pigments. Activated carbon has physical, chemical, and ion exchange adsorption functions for pigments in camellia oil. Compared to single adsorbents or other combinations, the chromatography column packed according to the above scheme exhibits better decolorization and peroxide value reduction effects.

[0012] According to the above scheme, the average particle size of the sulfonic acid silica gel adsorbent is 40-300 μm; the average particle size of the amino silica gel adsorbent is 40-300 μm; and the average particle size of the activated carbon is 20-200 mesh.

[0013] According to the above scheme, in step (1), the sulfonic acid silica gel adsorbent is a benzenesulfonic acid silica gel adsorbent or a propanesulfonic acid silica gel adsorbent.

[0014] According to the above scheme, in step (2), the amino silica gel adsorbent is an aminoethyl silica gel adsorbent, an aminopropyl silica gel adsorbent, or an aminobutyl silica gel adsorbent.

[0015] According to the above scheme, in step (2), when the filler is sulfonic acid silica gel adsorbent A-amino silica gel adsorbent-activated carbon, the amount of sulfonic acid silica gel adsorbent A is 0.1% to 10% of the oil weight, the amount of amino silica gel adsorbent is 0.1% to 10% of the oil weight, and the amount of activated carbon is 0.1% to 10% of the oil weight.

[0016] According to the above scheme, in step (2), when the filler is sulfonic acid silica gel adsorbent A-activated carbon, the amount of sulfonic acid silica gel adsorbent A is 0.1% to 10% of the oil weight, and the amount of activated carbon is 0.1% to 10% of the oil weight.

[0017] According to the above scheme, in step (3), the raw material camellia oil is one or more of cold-pressed camellia oil, degummed and deacidified camellia oil, refined camellia oil or edible camellia oil.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] (1) The present invention operates at a low temperature, effectively solving the problem of high temperature destroying the beneficial components of tea oil in traditional methods and with low energy consumption; no solvent is used to dissolve the oil, avoiding the safety problem of solvent residue; it can be used for the direct preparation of refined tea oil or commercial tea oil to first-grade colorless tea oil without changing the existing tea oil refining production line, which is simple to operate, has high production efficiency, and is easy to put into production; the chromatography column has a large adsorption capacity, and the amount of adsorbent used is greatly reduced compared with traditional adsorbents such as kaolin and attapulgite, which significantly reduces the amount of solid waste generated, has less environmental pollution, and meets the requirements of green production.

[0020] (2) This invention effectively solves the problem of poor decolorization effect of traditional camellia oil, and the product color reaches the first-grade white oil standard, which can meet the standards for medical and cosmetic oils; at the same time, its physicochemical parameters such as acid value and peroxide value meet the standards for cosmetic raw material camellia oil. The product of this invention has high quality, opens up a preparation path for colorless camellia oil, and provides technical support for the high-quality development of the camellia oil industry. Detailed Implementation

[0021] The invention will be further explained below with reference to specific embodiments.

[0022] Example 1

[0023] Take 1 kg of cold-pressed camellia oil, and weigh out 5% of benzenesulfonic acid silica gel adsorbent (55-75 μm), 5% aminopropyl silica gel adsorbent (55-75 μm), and 5% activated carbon (20-50 mesh) by weight of the oil. Soak the benzenesulfonic acid silica gel adsorbent in ultrapure water (7 times the volume of the packing material), methanol (3 times the volume of the packing material), and n-hexane (3 times the volume of the packing material) for 24 h, 6 h, and 24 h, respectively. Dry to constant weight to obtain benzenesulfonic acid adsorbent A. Then, pack the benzenesulfonic acid silica gel adsorbent A layer, aminopropyl silica gel adsorbent layer, and activated carbon layer into a chromatography column. Pass the cold-pressed camellia oil into the chromatography column and collect the filtrate to obtain colorless camellia oil.

[0024] Example 2

[0025] Take 1 kg of degummed and deacidified camellia oil, and weigh out 6% benzenesulfonic acid silica gel adsorbent (55-75 μm), 5% aminopropyl silica gel adsorbent (45-65 μm), and 8% activated carbon (20-50 mesh). Soak the benzenesulfonic acid silica gel adsorbent and propanesulfonic acid silica gel adsorbent in ultrapure water (6 times the volume of the packing material), methanol (3 times the volume of the packing material), and n-hexane (3 times the volume of the packing material) for 6 h, 3 h, and 3 h, respectively. Dry to constant weight to obtain benzenesulfonic acid silica gel adsorbent A. Then, pack the benzenesulfonic acid silica gel adsorbent A layer, aminopropyl silica gel adsorbent A layer, and activated carbon layer into a chromatography column. Pass the refined camellia oil into the chromatography column and collect the filtrate to obtain colorless camellia oil.

[0026] Example 3

[0027] Take 1 kg of commercially available refined camellia oil, and weigh out 4% propanesulfonic acid silica gel adsorbent (45-65 μm) and 5% activated carbon (20-50 mesh) by weight of the oil. Soak the propanesulfonic acid silica gel adsorbent in ultrapure water, methanol, and n-hexane (equivalent to 4 times the mass of the packing material) for 8 h, 3 h, and 3 h, respectively. Dry to constant weight to obtain propanesulfonic acid silica gel adsorbent A. Then, pack the propanesulfonic acid silica gel adsorbent A layer into a chromatography column in the order of activated carbon layer. Pass the commercially available refined camellia oil into the chromatography column and collect the filtrate to obtain colorless camellia oil.

[0028] Example 4

[0029] Take 1 kg of refined camellia oil, and weigh out 5% benzenesulfonic acid silica gel adsorbent (55-75 μm) and 5% activated carbon (20-50 mesh) by weight of the oil. Soak the benzenesulfonic acid silica gel adsorbent in ultrapure water (5 times the volume of the packing material), methanol (3 times the volume of the packing material), and n-hexane (3 times the volume of the packing material) for 5 h, 3 h, and 3 h respectively. Dry to constant weight to obtain benzenesulfonic acid silica gel adsorbent A. Then pack the benzenesulfonic acid silica gel adsorbent A layer into the chromatography column in the order of activated carbon layer. Pass the refined camellia oil into the chromatography column and collect the filtrate to obtain colorless camellia oil.

[0030] Example 5

[0031] Take 1 kg of refined camellia oil, and weigh out 3% propanesulfonic acid silica gel adsorbent (45-65 μm), 3% aminopropyl silica gel adsorbent (55-75 μm), and 5% activated carbon (20-50 mesh) by weight of the oil. Soak the propanesulfonic acid silica gel adsorbent in ultrapure water (3 times the volume of the packing material), methanol (3 times the volume of the packing material), and n-hexane (3 times the volume of the packing material) for 6 h, 4 h, and 3 h, respectively. Dry to constant weight to obtain propanesulfonic acid silica gel adsorbent A. Then pack the column into a chromatography column in the order of propanesulfonic acid silica gel adsorbent A layer - aminopropyl silica gel adsorbent layer - activated carbon layer. Pass the refined camellia oil into the chromatography column and collect the filtrate to obtain colorless camellia oil.

[0032] The colorless camellia oil and related indicators of the raw camellia oil obtained from the above five embodiments are shown in Table 1. The decolorization rate is calculated using the formula: Decolorization rate Y (%) = (Y... 原山茶油 -Y 无色山茶油 ) / Y 原山茶油 Decolorization rate R (%) = (R 原山茶油 -R 无色山茶油 ) / R Raw Camellia Oil; Peroxide Value Reduction Rate (%) = (Peroxide Value of Raw Camellia Oil - Peroxide Value of Colorless Camellia Oil) / Peroxide Value of Raw Camellia Oil

[0033] Table 1. Quality indicators of camellia oil and product from the examples.

[0034]

[0035] The determination of oil color shall be in accordance with GB / T22460-2008; the determination of acid value shall be in accordance with GB229-2016; and the determination of peroxide value shall be in accordance with GB227-2023.

[0036] As shown in Examples 1-5 in Table 1, the colorless camellia oil obtained after silica gel chromatography was reduced to red 0.1 and yellow less than or equal to 0.3. The acid value was reduced or remained unchanged, and the peroxide value was lower than that of the raw camellia oil by 60.7% to 84.6%. All indicators met or exceeded the standards for cosmetic camellia oil.

[0037] We compared and studied the effects of different pretreatment methods for adsorbents and fillers, as well as the order in which adsorbents were loaded, on the decolorization process of camellia oil.

[0038] Comparative Example 1

[0039] Take 1 kg of degummed and deacidified tea oil (same as in Example 2), and weigh out 10% of the oil weight of the following adsorbents: polyamide silica gel adsorbent, Florisil, C18 silica gel adsorbent, glycol-based silica gel adsorbent, quaternary ammonium salt silica gel adsorbent, cyano silica gel adsorbent, alumina, benzenesulfonic acid-based silica gel adsorbent, propanesulfonic acid-based silica gel adsorbent, aminopropyl silica gel adsorbent, activated carbon, C18 silica gel adsorbent-activated carbon combination (1:1), Florisil-activated carbon combination (1:1), and benzenesulfonic acid-based silica gel adsorbent-Floris-Crystal-Crystal-Activated Carbon combination. Florisil-aminopropyl silica gel-activated carbon combination (1:1), benzenesulfonic acid-aminopropyl silica gel adsorbent-activated carbon combination (1:1), propanesulfonic acid-aminopropyl silica gel adsorbent-activated carbon combination, benzenesulfonic acid-aminopropyl silica gel adsorbent-activated carbon combination (1:1:1), Florisil-aminopropyl silica gel adsorbent-activated carbon combination (1:1:1), and C18 silica gel adsorbent-aminopropyl silica gel adsorbent-activated carbon combination (1:1:1). These adsorbents were packed into chromatography columns, and degummed and deacidified camellia oil was passed through the columns. The filtered camellia oil was collected, and the results are shown in Table 2.

[0040] Table 2 Comparison of decolorization effects of various adsorbents

[0041]

[0042] Table 2 shows that activated carbon, benzenesulfonic acid silica gel adsorbent, and propanesulfonic acid silica gel adsorbent, when used alone, can significantly remove yellow pigment; activated carbon, benzenesulfonic acid silica gel adsorbent, propanesulfonic acid silica gel adsorbent, and aminopropyl silica gel adsorbent, when used alone, can remove red pigment to a certain extent; other adsorbents, when used alone, have no obvious decolorization effect.

[0043] Table 2 shows that the decolorization rate of the mixed adsorbent is better than that of the single adsorbent. Among the two adsorbent combinations, the propanesulfonic acid-based silica gel adsorbent-activated carbon (1:1) is better than other mixed adsorbents, with decolorization rates Y and R of 98.4% and 75%, respectively.

[0044] Table 2 shows that among the three adsorbent combinations, the decolorization rate R of benzenesulfonic acid silica gel adsorbent-aminopropyl silica gel adsorbent-activated carbon (1:1:1) is better than that of other mixed adsorbents, with decolorization rates Y and R being 98.9% and 83.3%, respectively.

[0045] We also investigated the effect of the order of loading benzenesulfonic acid-based silica gel adsorbent and activated carbon on the decolorization rate, and the results are shown in Table 3.

[0046] Table 3. Effect of filling order on tea oil decolorization rate

[0047]

[0048] Table 3 shows that filling with activated carbon first significantly improves the decolorization rate compared to filling with benzenesulfonic acid-based silica gel adsorbent first.

[0049] Comparative Example 2

[0050] Unlike Example 2, five portions of oil were weighed, containing 6% benzenesulfonic acid silica gel adsorbent, 5% aminopropyl silica gel adsorbent, and 8% activated carbon, respectively, to investigate the effects of different solvent combinations on the acid value and peroxide value of tea oil under pretreatment.

[0051] One sample of benzenesulfonic acid-based silica gel adsorbent was soaked in ultrapure water for 12 hours, another sample was soaked in methanol and n-hexane for 6 hours, another sample was soaked in water and methanol for 6 hours, another sample was soaked in water and n-hexane for 6 hours, and the last sample was soaked in a 1:1 mixture of petroleum ether and ethyl acetate for 12 hours. The remaining parameters and operations were the same as in Example 2. Camellia oil was collected and filtered out, and the results are shown in Table 4.

[0052] Table 4. Effects of different pretreatment methods on acid value and peroxide value

[0053]

[0054] Table 4 shows that, under the same total soaking time, the acid value remained basically unchanged when pretreated by soaking in water; the acid value increased significantly when pretreated by soaking in organic solvents (methanol, n-hexane, petroleum ether, ethyl acetate); and the peroxide value was reduced best when pretreated by soaking in water, methanol, or n-hexane.

[0055] Comparative Example 3

[0056] Unlike Example 2, two portions of adsorbent were weighed. One portion consisted of benzenesulfonic acid-based silica gel adsorbent with a particle size of 300–400 μm, aminopropyl silica gel adsorbent with a particle size of 300–400 μm, and activated carbon with a particle size of 5–10 mesh; this group of adsorbents was numbered 1. The other portion consisted of benzenesulfonic acid-based silica gel adsorbent with a particle size of 0.4–0.5 mm, aminopropyl silica gel adsorbent with a particle size of 0.4–0.5 mm, and activated carbon with a particle size of 10–20 mesh; this group of adsorbents was numbered 2. The remaining parameters and procedures were the same as in Example 2. The results are shown in Table 5.

[0057] Table 5. Effects of different adsorbent particle sizes on various indicators of tea oil.

[0058]

[0059] Table 5 shows that the particle size of the adsorbent affects the decolorization effect and quality indicators of tea oil. Larger adsorbent particle sizes result in poorer decolorization and a gradually decreasing rate of reduction in peroxide value.

[0060] Therefore, Tables 1 to 5 demonstrate that if the specified conditions in this invention are changed, the resulting colorless camellia oil is inferior to or not superior to the colorless camellia oil obtained by silica gel chromatography as described in this invention in terms of color or quality indicators.

Claims

1. A process for preparing colorless camellia oil by silica gel chromatography, characterized in that: Includes the following steps: Step (1), pretreatment of packing material: Soak the benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent in ultrapure water, methanol and n-hexane at a volume equivalent to 3 to 8 times its mass for 3 to 24 hours respectively, and then dry it to constant weight to obtain benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A. Step (2), column packing: The benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A obtained in step (1), activated carbon, and aminoethyl or aminopropyl silica gel adsorbent are used as packing material and packed into the column with a certain oil weight ratio. After compaction, the column is obtained. The packing material comprises the following two composition schemes: Option 1: Add activated carbon, aminoethyl or aminopropyl silica gel adsorbent, and benzenesulfonic acid or propanesulfonic acid silica gel adsorbent A sequentially to form a packing material; Option 2: Add activated carbon and benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A sequentially to form a packing material; Step (3), tea oil decolorization: At room temperature, the raw camellia oil is poured into the chromatography column obtained in step (2), filtered and the eluent is collected to obtain colorless camellia oil.

2. The process for preparing colorless camellia oil by silica gel chromatography according to claim 1, characterized in that: The average particle size of the benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent is 40–300 μm; the average particle size of the aminoethyl or aminopropyl silica gel adsorbent is 40–300 μm; and the average particle size of the activated carbon is 20–200 mesh.

3. The process for preparing colorless camellia oil by silica gel chromatography according to claim 1, characterized in that: In step (2), when the filler is benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A, aminoethyl or aminopropyl silica gel adsorbent, and activated carbon, the amount of benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A is 0.1% to 10% of the oil weight, the amount of aminoethyl or aminopropyl silica gel adsorbent is 0.1% to 10% of the oil weight, and the amount of activated carbon is 0.1% to 10% of the oil weight.

4. The process for preparing colorless camellia oil by silica gel chromatography according to claim 1, characterized in that: In step (2), when the filler is benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A and activated carbon, the amount of benzenesulfonic acid-based or propanesulfonic acid-based silica gel adsorbent A is 0.1% to 10% of the oil weight, and the amount of activated carbon is 0.1% to 10% of the oil weight.

5. The process for preparing colorless camellia oil by silica gel chromatography according to claim 1, characterized in that: In step (3), the raw material camellia oil is one or more of cold-pressed camellia oil, degummed and deacidified camellia oil, refined camellia oil or edible camellia oil.

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