Purification method of lauroyl glycine
By adjusting the pH value in the reaction system of lauroyl glycine and using hollow fiber membranes for membrane separation, the problems of environmental protection and high energy consumption of traditional purification methods are solved, and efficient purification of lauroyl glycine and green and environmentally friendly production process are achieved.
Patent Information
- Application Number
- CN202510016563.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-06
- Publication Date
- 2025-04-29
AI Technical Summary
The prior art has problems such as low environmental protection, high energy consumption and low separation efficiency in the purification process of lauroyl glycine, and it is difficult for traditional ceramic membranes to effectively separate lauroyl glycine.
By adjusting the pH value of the reaction system to 7.2-7.8, the membrane separation was performed using a hollow fiber membrane, and the molecular weight was cut off from 800-1200, the separation and purification of lauroyl glycine was achieved.
The efficient purification of lauroyl glycine is achieved, which reduces production costs. This method is suitable for the lauroyl glycine system synthesized by chemical and biological methods, and has the characteristics of green and environmental protection.
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of biotechnology and relates to a purification method and a production method of lauroylglycine. Background Art
[0002] Sodium lauroyl glycinate is an amino acid surfactant and a renewable green environmentally friendly surfactant based on biomass. Sodium lauroyl glycinate surfactant not only has a wide source of raw materials, low toxicity and side effects, mild performance, low irritation, good biodegradability, and green production process, but also has good emulsification, wetting, solubilization, dispersion, foaming and other properties. It has attracted much attention and is gradually used in many fields such as washing, personal care and food industry. Sodium lauroyl glycinate can be obtained from lauroyl glycine through a simple saponification reaction.
[0003] At present, the synthesis of lauroyl glycine is mainly chemical and biological, and the purification method is mainly extraction and recrystallization. However, the above traditional purification methods are not green and environmentally friendly; the energy consumption in the production process is high, which is not conducive to controlling production costs.
[0004] Membrane separation is a commonly used separation method in the biological field. However, using traditional ceramic membranes for separation, a 20nm pore size is still not enough to separate lauric acid and lauroylglycine. If the pore size is further reduced, the separation speed will be reduced, and the separation will be extremely slow. In addition, lauric acid and lauroylglycine cannot be completely separated. As a result, traditional membrane separation is not used in the purification of lauroylglycine. Summary of the invention
[0005] In order to achieve the purification and separation of lauroyl glycine, the present invention is verified through different separation experimental conditions, and unexpectedly finds that with the change of pH value, lauroyl glycine can be retained by a membrane with a lower molecular weight, while other components can pass through the membrane, thereby achieving the separation of lauroyl glycine, and the method is suitable for separating lauroyl glycine from its aqueous solution system, and is suitable for the system of chemical and biological synthesis of lauroyl glycine.
[0006] Therefore, the present invention provides a method for purifying lauroyl glycine, which separates the product lauroyl glycine from the lauroyl glycine reaction solution by membrane separation. The molecular weight cutoff of the membrane is 800-1200, and the pH value of the system is 7.2-7.8.
[0007] In a preferred embodiment, the reaction system of lauroyl glycine is adjusted to a pH of 7.4-7.6.
[0008] More preferably, the reaction system of lauroyl glycine is adjusted to a pH of 7.5.
[0009] In a preferred embodiment, the hollow fiber membrane has a molecular weight cut-off of 900-1100.
[0010] More preferably, the hollow fiber membrane has a molecular weight cut-off of 950-1050.
[0011] In a preferred embodiment, the flux is 5-6 L / h.
[0012] Preferably, lauroyl glycine is present in an aqueous solution and is in a uniform and transparent state with good fluidity.
[0013] In a specific embodiment, the aqueous solution contains 40-90% water, the aqueous phase is pure water, and lauroyl glycine is separated from the aqueous solution system containing glycine and / or lauric acid. The glycine aqueous solution contains 0-60% glycerol, preferably 40-60%, 0-5% lauric acid, and 3-10% lauroyl glycine.
[0014] The purification method is used for purifying lauroyl glycine synthesized by chemical method or biological method. This system is a universal system of the purification method of the present invention, and can obtain the corresponding product regardless of whether lauroyl glycine is synthesized by chemical method or biological method.
[0015] The invention realizes a pure green and environmentally friendly method for purifying lauroyl glycine, separates and purifies lauroyl glycine in a reaction system of a lauroyl glycine aqueous solution, and the operation is simpler, which is beneficial to the control of production costs. DETAILED DESCRIPTION
[0016] The present invention is further described below through specific examples in order to better understand the present invention, but does not constitute a limitation of the present invention.
[0017] Example 1 The reaction system contained 90% glycine aqueous solution, 4.5% lauroyl glycine, 5.5% lauric acid, and pH = 7.5. The above system was passed through a 1000 molecular weight hollow fiber membrane device with a flux of 5 L / h. After concentration, the lauroyl glycine content of the permeate was detected by HPLC, and the lauroyl glycine content of the retentate was detected by HPLC.
[0018] Example 2 The reaction system contained 50% glycine aqueous solution, 40% glycerol, 4.5% lauroyl glycine, 5.5% lauric acid, and pH = 7.5. The above system was passed through a 1000 molecular weight hollow fiber membrane device with a flux of 5 L / h. After concentration, the lauroyl glycine content of the permeate was detected by HPLC, and the lauroyl glycine content of the retentate was detected by HPLC.
[0019] Example 3 The reaction system contained 50% glycine aqueous solution, 40% glycerol, 4.5% lauroyl glycine, 5.5% lauric acid, pH=7.5, and the above system was passed through a 1500 molecular weight hollow fiber membrane device with a flux of 5.5 L / h. After concentration, the lauroyl glycine content of the permeate was detected by HPLC, and the lauroyl glycine content of the retentate was detected by HPLC.
[0020] Example 4 The reaction system contained 90% glycine aqueous solution, 4.5% lauroyl glycine, 5.5% lauric acid, and pH = 7.0. The above system was passed through a 2500 molecular weight hollow fiber membrane device with a flux of 6 L / h. After concentration, the lauroyl glycine content of the permeate was detected by HPLC, and the lauroyl glycine content of the retentate was detected by HPLC.
[0021] Example 5 The reaction system contained 50% glycine aqueous solution, 40% glycerol, 4.5% lauroyl glycine, 5.5% lauric acid, and pH=6.5. The system was passed through a 1000 molecular weight hollow fiber membrane device with a flux of 5 L / h. After concentration, the lauroyl glycine content of the permeate was detected by HPLC, and the lauroyl glycine content of the retentate was detected by HPLC.
[0022] The product detection method involved in the above examples and comparative examples is as follows: the product is detected by high performance liquid chromatography, and the test parameters are: chromatographic column: C18, 250mm; mobile phase: 85% acetonitrile and 15% 0.05% trifluoroacetic acid aqueous solution; detection wavelength: 220nm; column temperature: 30°C; flow rate: 1mL / min; detection time: 15min. The content of lauroyl glycine in the retentate of each example is recorded, and the specific results are shown in Table 1: Table 1. Content of lauroyl glycine in the retentate
[0023] By comparing Example 1 with Example 4, it can be determined that the separation effect of lauroyl glycine in the system at pH = 7.5 is better than that at pH = 7.0 and 6.5; by comparing Example 2 with Example 3, under the same system, the 1000 molecular weight membrane has a better separation effect; Example 1 and Example 2 show that the separation method has basically the same separation effect whether there is glycerol in the system, and the viscosity has little effect on the separation effect. And the separation effect is significantly reduced when the pH is reduced to 6.5.
[0024] The content of lauroyl glycine in the permeate of each example was recorded. The specific results are shown in Table 2: Table 2. Lauroylglycine content in the permeate
[0025] As shown in Tables 1 and 2, lauroyl glycine can be retained by membranes of corresponding molecular weights, indicating that under certain pH conditions, lauroyl glycine aggregates into molecules with larger relative molecular weights, and can thus be separated using the method of this patent.
Claims
1. A method for purifying lauroylglycine, characterized in that: A hollow fiber membrane is used to separate lauroyl glycine from the system; wherein the molecular weight cutoff of the membrane is 800-1200, and the pH value of the system is 7.2-7.
8.
2. The purification method according to claim 1, characterized in that , the reaction system of lauroyl glycine was adjusted to pH 7.4-7.
6.
3. The purification method according to claim 2, characterized in that , the reaction system of lauroyl glycine was adjusted to pH 7.
5.
4. The purification method according to claim 1, characterized in that The hollow fiber membrane has a molecular weight cut-off of 900-1100.
5. The purification method according to claim 4, characterized in that The molecular weight cut-off of the hollow fiber membrane is 950-1050.
6. The purification method according to claim 1, characterized in that The flux is 5-6L / h.
7. The purification method according to claim 1, characterized in that Lauroyl glycine exists in aqueous solution and is uniform and transparent with good fluidity.
8. The purification method according to claim 7, characterized in that The aqueous solution contains 40-90% water, the aqueous phase is purified, or is a corresponding glycine aqueous solution, contains 0-60% glycerol, preferably 40-60%, contains 0-5% lauric acid, and contains 3-10% lauroyl glycine.
9. The purification method according to claim 1, characterized in that The purification method is used for separating lauroyl glycine from an aqueous solution system containing glycine and / or lauric acid.
10. The purification method according to any one of claims 1 to 9, characterized in that: The purification method is used for purifying lauroylglycine synthesized by chemical method or biological method.