A method of reducing low temperature haze in fatty alcohol polyether

Abstract

The application discloses a method for reducing low-temperature turbidity of fatty alcohol polyether, and belongs to the technical field of fatty alcohol polyether preparation. The method comprises the following steps: heating and stirring the low-temperature turbid fatty alcohol polyether to be transparent, adding acid or alkali, stirring under the condition of heat preservation, adding an adsorbent, continuing to stir, increasing temperature to dehydrate, cooling, stirring after the dehydration is completed, and filtering under the condition of heat preservation and negative pressure. The method can significantly reduce the turbidity of the low-temperature turbid problem product or make the problem product not appear turbidity at low temperature by means of acid treatment or alkali treatment, adsorption and low-temperature filtration.

Description

Technical Field

[0001] This invention relates to the field of fatty alcohol polyether preparation technology, and specifically to a method for reducing the low-temperature turbidity of fatty alcohol polyethers. Background Technology

[0002] Fatty alcohol polyethers are a class of nonionic surfactants with the most varieties, largest production volume, and most important status. They are widely used in the detergent and cosmetic industries as emulsifiers, dispersants, or wetting agents, and can also be used as raw materials for the preparation of anionic surfactants such as alcohol ether sulfates via sulfonation reactions. In actual production, fatty alcohol polyethers are prone to low-temperature turbidity due to factors such as raw materials or processes. This not only makes the product's appearance inferior, making it difficult to use in high-end shampoos or concentrated laundry detergents where appearance requirements are high, but also adversely affects the product's low-temperature performance, especially in colder northern regions.

[0003] The article "Discussion on the Causes of Low-Temperature Turbidity of Fatty Alcohol Polyoxyethylene (3) Ethers" indicates that fatty alcohol polyethers with high degree of addition are an important cause of low-temperature turbidity, while raw materials and fatty alcohol polyethers with low degree of addition do not cause low-temperature turbidity. The article "Study on the Influence of Polyethylene Glycol on Low-Temperature Turbidity of Fatty Alcohol Polyoxyethylene Ethers" indicates that polyethylene glycol with high degree of addition has an impact on low-temperature turbidity, while polyethylene glycol with low degree of addition can prevent the formation of low-temperature turbidity. The article "Preliminary Study on Low-Temperature Turbidity of AEO Series Products" indicates that production process factors such as the type and amount of catalyst and reaction temperature in the reaction process of fatty alcohol polyethers can lead to low-temperature turbidity, possibly due to the generation of byproducts such as aldehydes and esters or high molecular weight polyethers during the reaction. The low-temperature turbidity problem of fatty alcohol polyethers is mostly caused by the presence of aldehydes, esters, or excessive high molecular weight components in the product. For example, excessive aldehydes, esters, or other byproducts may be generated in the raw materials, or by improper polyether reaction processes may result in the formation of fatty alcohol polyethers, aldehydes, esters, or other byproducts; or factors such as slow stirring, excessively high reaction temperature, or excessively fast epoxide addition may lead to the formation of fatty alcohol polyethers and polyethylene glycols with excessively large molecular weights.

[0004] Currently, to prevent the production of substandard low-temperature turbidity products, manufacturers generally avoid producing such polyether products by selecting high-purity raw materials and developing and using advanced and stable production processes. However, this approach results in high production costs and difficult-to-overcome technological barriers. When manufacturers do produce low-temperature turbidity fatty alcohol polyethers, they typically treat them as substandard products and use them in products where turbidity requirements are not high.

[0005] Therefore, it is essential to develop a method to reduce the low-temperature turbidity of fatty alcohol polyethers in order to solve the problem of limited application of substandard products with low-temperature turbidity produced in factories. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method for reducing the turbidity of fatty alcohol polyethers at low temperatures. This method, through acid treatment or alkali treatment combined with low-temperature adsorption filtration, can significantly reduce the turbidity of problematic products at low temperatures or prevent the problematic products from exhibiting turbidity at low temperatures.

[0007] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0008] A method for reducing the low-temperature turbidity of fatty alcohol polyethers includes the following steps:

[0009] S1. Heat and stir the low-temperature turbid fatty alcohol polyether until it becomes transparent;

[0010] S2. Add acid or alkali to the fatty alcohol polyether in step S1 and stir for 20-90 minutes under heat preservation.

[0011] S3. Add adsorbent to the fatty alcohol polyether in step S2, stir for 20-120 min, and then slowly heat up while dehydrating. When the temperature reaches 70-130℃, keep it at the temperature for 30-120 min to dehydrate.

[0012] S4. After dehydration, cool to 0-60℃ and stir for 30-90 minutes. Keep warm and vacuum filter to obtain the final product.

[0013] In a preferred embodiment of the present invention, the fatty alcohol polyether in step S1 is an EO polyether, PO polyether, or a block polyether or random polyether composed of EO / PO with a molecular weight of less than 2000.

[0014] In a preferred embodiment of the present invention, the initiator of the fatty alcohol polyether in step S1 is a high-carbon n-primary alcohol, wherein the high-carbon n-primary alcohol is a C8 alcohol or a C6 alcohol. 10 alcohols, C 12 alcohols, C 14 alcohols, C 16 alcohols, C 18 alcohols, C 20 alcohols, C 12-14 alcohol or C 18-16 One or any mixture of two or more alcohols.

[0015] In a preferred embodiment of the present invention, step S1 involves heating to 40–90°C, preferably 50–70°C.

[0016] In a preferred embodiment of the present invention, the amount of acid or alkali added in step S2 is 0.1% to 5% of the mass of fatty alcohol polyether, preferably 0.5% to 3%.

[0017] In a preferred embodiment of the present invention, the acid or base mentioned in step S2 is a strong acid or a strong base, preferably a strong acid; the strong acid is one or a mixture of any two or more of sulfuric acid, nitric acid, hydrochloric acid, perchloric acid, hydroiodic acid or hydrobromic acid; the strong base is one or a mixture of any two or more of potassium hydroxide, calcium hydroxide, sodium hydroxide, barium hydroxide or cesium hydroxide.

[0018] In a preferred embodiment of the present invention, the mass concentration of the acid or base in step S2 is 10% to 99%, preferably 20% to 98%.

[0019] In a preferred embodiment of the present invention, the amount of adsorbent used in step S3 is 0.1% to 5% of the mass of fatty alcohol polyether, preferably 0.5% to 4%.

[0020] In a preferred embodiment of the present invention, the adsorbent is one or a mixture of any two or more of magnesium hexasilicate, alumina, magnesium aluminum silicate, amorphous silica, or molecular sieve, preferably a mixture of magnesium hexasilicate and molecular sieve.

[0021] In a preferred embodiment of the present invention, the adsorption temperature of step S3 is 0-60℃, preferably 5-40℃; the heating rate of step S3 is 1-10℃ / min; and the heat preservation and dehydration temperature is 70-130℃, preferably 85-110℃.

[0022] In a preferred embodiment of the present invention, the heat preservation and filtration temperature in step S4 is 0-60°C, preferably 0-40°C.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] This invention treats substandard fatty alcohol polyethers that are turbid at low temperatures by using acid or alkali treatment and adsorption filtration. This significantly reduces the turbidity of fatty alcohol polyethers at low temperatures or prevents them from becoming turbid at low temperatures, making the product transparent. This effectively solves the problem of product turbidity at low temperatures caused by uncertain factors such as raw materials or production processes. Attached Figure Description

[0025] Figure 1 This is a photograph of the product before treatment with the fatty alcohol polyether described in this invention.

[0026] Figure 2 This is a comparison chart of the fatty alcohol polyether products after treatment in Example 1 and Comparative Examples 1, 2, and 3 of the present invention. Detailed Implementation

[0027] A method for reducing the low-temperature turbidity of fatty alcohol polyethers includes the following steps:

[0028] S1. Heat the low-temperature turbid fatty alcohol polyether to 40-90°C and stir until transparent;

[0029] S2. Add an acid or alkali with a mass concentration of 10% to 99% to the fatty alcohol polyether in step S1 at 0.1% to 5% of the mass of the fatty alcohol polyether, and stir for 20 to 90 minutes under heat preservation.

[0030] S3. Add adsorbent to the fatty alcohol polyether in step S2 at 0.1% to 5% of the mass of fatty alcohol polyether. Stir at an adsorption temperature of 0 to 60°C for 20 to 120 minutes. Then, heat and dehydrate at a heating rate of 1 to 10°C / min. Keep the temperature at 70 to 130°C for 30 to 120 minutes to dehydrate.

[0031] S4. After dehydration, cool to 0-60℃, stir for 30-90 minutes, keep warm and vacuum filter to obtain the final product.

[0032] The fatty alcohol polyether in step S1 is an EO polyether, PO polyether, or a block polyether or random polyether composed of EO / PO with a molecular weight less than 2000. The initiator for the fatty alcohol polyether in step S1 is a high-carbon n-primary alcohol, wherein the high-carbon n-primary alcohol is a C8 alcohol, C... 10 alcohols, C 12 alcohols, C 14 alcohols, C 16 alcohols, C 18 alcohols, C 20 alcohols, C 12-14 alcohol or C 18-16 The alcohol is one or a mixture of any two or more alcohols. The acid or base added in step S2 is a strong acid or a strong base, preferably a strong acid; wherein the strong acid is one or a mixture of any two or more sulfuric acid, nitric acid, hydrochloric acid, perchloric acid, hydroiodic acid, or hydrobromic acid; and the strong base is one or a mixture of any two or more potassium hydroxide, calcium hydroxide, sodium hydroxide, barium hydroxide, or cesium hydroxide. The adsorbent is one or a mixture of any two or more magnesium hexasilicate, alumina, magnesium aluminum silicate, amorphous silica, or molecular sieves, preferably a mixture of magnesium hexasilicate and molecular sieves.

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments to help those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention. The scope of protection of the present invention includes, but is not limited to, the following embodiments. Any modifications made to the details and form of the technical solution of the present invention without departing from the spirit and scope of this application shall fall within the scope of protection of the present invention.

[0034] Example 1:

[0035] A method for reducing the low-temperature turbidity of fatty alcohol polyethers includes the following steps:

[0036] S1, 500g of low-temperature turbid C 18-16 Alcohol random polyether (average molecular weight of 2000, EO / PO mass ratio of PO:EO = 3:1) was heated to 60°C and stirred until transparent;

[0037] S2, to C in step S1 18-16 Add 5.9g of 85% sulfuric acid to the alcohol random polyether and stir for 30min under heat preservation.

[0038] S3, to C in step S2 18-16 Add 5g of magnesium hexasilicate adsorbent to alcohol random polyether, stir at an adsorption temperature of 60℃ for 40min, and then dehydrate while heating at a heating rate of 3℃ / min. When the temperature reaches 105℃, keep it at that temperature for 60min to dehydrate.

[0039] S4. After dehydration, cool to 10℃, stir for 60 minutes, and then filter under negative pressure at this temperature to obtain a product that is not easily cloudy at low temperatures.

[0040] Comparative Example 1:

[0041] A method for reducing the low-temperature turbidity of fatty alcohol polyethers includes the following steps:

[0042] S1, 500g of low-temperature turbid C 18-16 Alcohol-based random polyether (same as in Example 1) was heated to 60°C and stirred until transparent;

[0043] S2, to C in step S1 18-16 Add 5.9g of deionized water to the alcohol random polyether and stir for 30min under heat preservation;

[0044] S3, to C in step S2 18-16 Add 5g of magnesium hexasilicate adsorbent to alcohol random polyether, stir at an adsorption temperature of 60℃ for 40min, and then dehydrate while heating at a heating rate of 3℃ / min. When the temperature reaches 105℃, keep it at that temperature for 60min to dehydrate.

[0045] S4. After dehydration, cool to 10℃, stir for 60 minutes, and filter under negative pressure at this temperature to obtain the processed product.

[0046] Comparative Example 2:

[0047] A method for reducing the low-temperature turbidity of fatty alcohol polyethers includes the following steps:

[0048] S1, 500g of low-temperature turbid C 18-16Alcohol-based random polyether (same as in Example 1) was heated to 60°C and stirred until transparent;

[0049] S2, to C in step S1 18-16 Add 5.9g of 85% sulfuric acid to the alcohol random polyether and stir for 30min under heat preservation.

[0050] S3. After acidification, stir at 60℃ for 40 minutes, and dehydrate while heating at a rate of 3℃ / min. When the temperature reaches 105℃, keep it at that temperature for 60 minutes to dehydrate.

[0051] S4. After dehydration, cool to 10℃, stir for 60 minutes, and filter under negative pressure at this temperature to obtain the processed product.

[0052] Comparative Example 3:

[0053] S1, 500g of low-temperature turbid C 18-16 Alcohol-based random polyether (same as in Example 1) was heated to 60°C and stirred until transparent;

[0054] S2, to C in step S1 18-16 Add 5.9g of 85% sulfuric acid to the alcohol random polyether and stir for 30min under heat preservation.

[0055] S3, to C in step S2 18-16 Add 5g of magnesium hexasilicate adsorbent to alcohol random polyether, stir at an adsorption temperature of 60℃ for 40min, and then dehydrate while heating at a heating rate of 3℃ / min. When the temperature reaches 105℃, keep it at that temperature for 60min to dehydrate.

[0056] S4. After dehydration, cool to 70℃ and filter under negative pressure to obtain the processed product.

[0057] Example 2:

[0058] The only difference between this embodiment and Embodiment 1 is that the fatty alcohol polyether in step S1 is AEO3, while other conditions remain unchanged.

[0059] Example 3:

[0060] The only difference between this embodiment and Embodiment 1 is that the fatty alcohol polyether in step S1 is C 20 Alcohol-block polyether (average molecular weight 1000, mass fraction ratio PO:EO = 1:2), other conditions unchanged.

[0061] Example 4:

[0062] The only difference between this embodiment and Embodiment 1 is that in step S2, a mixed acid consisting of 5g of concentrated hydrochloric acid with a mass concentration of 37% and 5g of concentrated nitric acid with a mass concentration of 68% is added, while other conditions remain unchanged.

[0063] Example 5:

[0064] The only difference between this embodiment and Embodiment 1 is that 5g of potassium hydroxide solution with a mass concentration of 75% is added in step S2, while other conditions remain unchanged.

[0065] Example 6:

[0066] The only difference between this embodiment and Embodiment 1 is that the dehydration temperature in step S3 is 90°C, while other conditions remain unchanged.

[0067] Example 7:

[0068] The only difference between this embodiment and Example 1 is that 20g of a mixture of magnesium hexasilicate and molecular sieve is added in step S3 (magnesium hexasilicate and molecular sieve are mixed in a mass ratio of 1:1), while other conditions remain unchanged.

[0069] Example 8:

[0070] The only difference between this embodiment and Embodiment 1 is that in step S4, the temperature is reduced to 40°C, while other conditions remain unchanged.

[0071] Low-temperature turbidity comparison experiment:

[0072] The turbidity of fatty alcohol polyethers before and after treatment in Examples 1-8 and Comparative Examples 1-3 was measured after being placed in a constant temperature oven at 10°C for 5 hours. The results are as follows: Figure 1 , Figure 2 And as shown in Table 1.

[0073] Table 1. Turbidity of each sample before and after treatment

[0074] sample Turbidity (NTU) before treatment Turbidity after treatment (NTU) Example 1 68 0 Comparative Example 1 68 42 Comparative Example 2 68 26 Comparative Example 3 68 55 Example 2 54 2 Example 3 93 3 Example 4 68 0 Example 5 68 1 Example 6 68 1 Example 7 68 3 Example 8 68 2

[0075] As shown in Table 1, the turbidity of the problematic polyether products in Examples 1-8 and Comparative Examples 1-3 before treatment was greater than 50 NTU at low temperatures (below 10°C). Figure 1 The unqualified C samples before treatment in Example 1 and Comparative Examples 1, 2, and 3. 18-16 Photographs of random polyether products, by Figure 1 It can be seen that C 18-16 The alcohol random polyether was turbid, and its turbidity at low temperature (10°C) was measured to be 68 NTU. Figure 2 This is a comparison chart of the fatty alcohol polyether products treated in Example 1 and Comparative Examples 1, 2, and 3. Figure 2It can be seen that after treatment, the polyether sample in Example 1 became transparent. While the turbidity of Comparative Examples 1, 2, and 3 improved somewhat after certain treatments, it remained noticeably turbid. Data in Table 1 shows that the turbidity of the polyether samples treated in Examples 1-8 was all below 3, and they were essentially transparent and turbid-free at low temperatures. This demonstrates that using the method of this invention to treat polyethers with low-temperature turbidity issues can significantly reduce the turbidity of fatty alcohol polyethers at low temperatures or prevent turbidity from occurring at low temperatures, resulting in a transparent product appearance.

[0076] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for reducing the low-temperature turbidity of fatty alcohol polyethers, characterized in that: Includes the following steps: S1. Heat the low-temperature turbid fatty alcohol polyether to 40~90℃ and stir until transparent; S2. Add acid or alkali to the fatty alcohol polyether in step S1, and stir for 20-90 minutes under heat preservation; wherein, the amount of acid or alkali added is 0.1%-5% of the mass of fatty alcohol polyether; S3. Add adsorbent to the fatty alcohol polyether in step S2, stir at an adsorption temperature of 0~60℃ for 20~120min, and then heat up and dehydrate at a heating rate of 1~10℃ / min until the temperature reaches 70~130℃ and is kept at that temperature for 30~120min. S4. After dehydration, cool to 0~60℃ and stir for 30~90 minutes. Keep warm and filter under negative pressure to obtain the product. The fatty alcohol polyether is an EO polyether, PO polyether, or a block polyether or random polyether composed of EO / PO with a molecular weight of less than 2000; the initiator of the fatty alcohol polyether is a high-carbon n-primary alcohol, wherein the high-carbon n-primary alcohol is a C8 alcohol, C... 10 alcohols, C 12 alcohols, C 14 alcohols, C 16 alcohols, C 18 alcohols, C 20 alcohols, C 12-14 alcohol or C 18-16 One or any mixture of two or more alcohols.

2. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1, characterized in that: Step S1: Heat to 50~70℃.

3. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1, characterized in that: In step S2, the amount of acid or alkali added is 0.5% to 3% of the mass of the fatty alcohol polyether.

4. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1 or 3, characterized in that: The acid or base mentioned in step S2 is a strong acid or a strong base; the strong acid is one or a mixture of any two or more of sulfuric acid, nitric acid, hydrochloric acid, perchloric acid, hydroiodic acid or hydrobromic acid; the strong base is one or a mixture of any two or more of potassium hydroxide, calcium hydroxide, sodium hydroxide, barium hydroxide or cesium hydroxide.

5. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 4, characterized in that: The mass concentration of the acid or base mentioned in step S2 is 10% to 99%.

6. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 4, characterized in that: The mass concentration of the acid or base mentioned in step S2 is 20% to 98%.

7. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1, characterized in that: In step S3, the amount of adsorbent used is 0.1% to 5% of the mass of fatty alcohol polyether.

8. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1 or 7, characterized in that: The adsorbent is one or a mixture of any two or more of the following: magnesium hexasilicate, alumina, magnesium aluminum silicate, amorphous silica, or molecular sieve.

9. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1 or 8, characterized in that: The adsorbent is a mixture of magnesium hexasilicate and molecular sieve.

10. The method for reducing the low-temperature turbidity of fatty alcohol polyethers according to claim 1, characterized in that: The adsorption temperature in step S3 is 5~40℃; the heating rate in step S3 is 1~10℃ / min; and the heat preservation and dehydration temperature is 85~110℃.

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