A method for extracting betaine from sugar beet molasses
An integrated method combining ceramic membrane microfiltration, nanofiltration membrane purification, and continuous chromatographic separation has solved the problems of high efficiency and environmental protection in betaine extraction from beet molasses, achieving high-purity and high-yield betaine extraction suitable for large-scale production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG SHUANGZI INTELLIGENT EQUIP CO LTD
- Filing Date
- 2026-05-28
- Publication Date
- 2026-07-14
AI Technical Summary
Existing technologies for extracting betaine from beet molasses suffer from problems such as cumbersome processes, low yields, low purity, and environmental unfriendliness. In particular, ion exchange resin methods are prone to pollution, fermentation conversion methods are costly and require secondary separation, and membrane separation technologies cannot simultaneously achieve high yields and high purity.
An integrated approach combining ceramic membrane microfiltration, nanofiltration, and continuous chromatography separation, along with specific operating conditions including hydrophilic and charge modification of the ceramic membrane, was employed. Betaine was separated from impurities at 75°C using a multi-column continuous chromatography system, with water as the primary solvent, avoiding the use of organic solvents.
It achieves efficient extraction of betaine with a purity of no less than 98% and a yield of no less than 80%, and the process is environmentally friendly with low energy consumption and low wastewater generation.
Smart Images
Figure CN122380976A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of natural product extraction technology, specifically relating to a method for extracting betaine from beet molasses. Background Technology
[0002] Beet molasses, a byproduct of the sugar industry (containing 7%-10% betaine and approximately 46% total sugar), is a high-quality raw material for extracting natural betaine. Betaine is a natural organic compound with the chemical formula C5H. 11 NO2, originally discovered in beet molasses, is an amphoteric compound whose core properties include acting as a methyl donor, regulating osmotic pressure, and stabilizing cell structure.
[0003] In the medical field, betaine is mainly used to promote fat metabolism and protect the liver. It helps break down fat by participating in choline synthesis, preventing fatty liver, and improving liver fibrosis and transaminase levels. At the same time, it can lower homocysteine levels to reduce the risk of cardiovascular disease and alleviate chronic inflammation such as rheumatoid arthritis by inhibiting inflammatory pathways.
[0004] In cosmetics, betaine is widely used due to its moisturizing and antistatic properties. It can stabilize the osmotic pressure of skin cells, enhance barrier repair, and is suitable for sensitive skin and anti-aging products.
[0005] In industrial applications, betaine, as a surfactant, acts as a softener and a detergency and bactericide in detergents, while also improving animal growth efficiency and disease resistance in agricultural feed.
[0006] In terms of market prospects, the global betaine market is projected to grow from US$3.89 billion in 2023 at a CAGR of 6.2% to US$5.25 billion in 2028, and may exceed US$6 billion in 2030. As a major producer and consumer, the Chinese market is expected to exceed RMB 23 billion in 2025 and reach RMB 30 billion in 2030, accounting for more than 50% of the global market share. This growth is driven by demand for osmotic pressure regulators from the livestock and poultry farming industry and policy support for environmentally friendly feed.
[0007] Betaine is an important quaternary ammonium alkaloid. As a highly efficient methyl donor, it plays a vital role in animal metabolism, osmotic regulation, and meat quality improvement, and is widely used in feed, food, and pharmaceutical fields. Beet molasses is the main natural source of betaine, but its complex composition, containing large amounts of sucrose, fructose, glucose, salts, and pigments, presents challenges for its separation and purification. Existing technologies, such as ion exchange resin methods, are cumbersome and prone to resin contamination; fermentation conversion methods, while utilizing sugars, are costly and require secondary separation. Membrane separation technology has its advantages, but single membrane processes often struggle to achieve both high yields and high purity simultaneously. Therefore, developing an integrated, green, and efficient method for extracting betaine from beet molasses is crucial. Summary of the Invention
[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a betaine extraction method that is simple in process, has a high yield, good product purity, and is environmentally friendly.
[0009] In a first aspect, the present invention provides a method for extracting betaine from beet molasses, comprising the following steps: (1) Raw material pretreatment: Dilute beet molasses with water; (2) Ceramic membrane microfiltration: The diluted solution obtained in step (1) is subjected to ceramic membrane microfiltration treatment, and the permeate is collected; (3) Nanofiltration membrane purification: The permeate obtained in step (2) is subjected to nanofiltration treatment, and the retentate is collected; (4) Continuous chromatographic separation: The nanofiltration retentate obtained in step (3) is passed into a continuous chromatographic system composed of multiple chromatographic columns for separation, and the component solution rich in betaine is collected; (5) Crystallization and drying: The betaine-rich component solution obtained in step (4) is concentrated, crystallized, separated and dried to obtain the betaine product.
[0010] Optionally, in step (1), the water is pure water, and the weight ratio of the pure water to beet molasses is (1.5-2.0):1.
[0011] Optionally, in step (2), the operating conditions of the ceramic membrane microfiltration are as follows: a ceramic membrane with a pore size of 80 nm is used, the operating temperature is 55-60℃, the feed pressure is 0.22-0.23 MPa, and dialysis water equivalent to 30%-35% of the total feed volume is added.
[0012] Optionally, in step (3), the operating conditions for nanofiltration membrane purification are as follows: a nanofiltration membrane with a molecular weight cutoff of 200 Da is used, the inlet pressure is 2.0-2.3 MPa, and dialysis water equivalent to 35%-42% of the total feed volume of the microfiltration permeate is added.
[0013] Optionally, in step (4), the continuous chromatography system consists of 7 columns, which are filled with styrene-divinylbenzene type cation exchange resin; the feed solution enters from the 7th column, the elution water enters from the 1st column, the system temperature is 75°C, and the component solution rich in betaine is collected from the outlet of the 3rd column.
[0014] Optionally, in step (5), the concentration is carried out under vacuum conditions, with a vacuum degree of -0.08 to -0.09 MPa and a temperature of 65–70°C; the crystallization is carried out by cooling the concentrate to 18°C and allowing it to stand for crystallization; the drying temperature is 60°C.
[0015] Optionally, in step (2), the ceramic membrane is a ceramic membrane that has undergone hydrophilic modification and charge modification.
[0016] Optionally, the hydrophilic modification and charge modification are achieved by forming a SiO2-P2O5 composite modification layer on the surface of the ceramic film using a sol-gel coating method.
[0017] Optionally, the preparation of the sol includes: mixing tetraethyl orthosilicate, anhydrous ethanol, deionized water and hydrochloric acid in a molar ratio of 1:20:4:0.05, adding triethyl phosphate in a molar ratio of 1:20 to tetraethyl orthosilicate, and refluxing and stirring at 60°C for 4 hours to form a composite sol.
[0018] Optionally, the final betaine product should have a purity of not less than 98% and a total yield of not less than 80%.
[0019] The core of this invention is to achieve efficient extraction of betaine by optimizing the operating conditions of each unit through the efficient integration of membrane separation and continuous chromatography. 1. Innovative application of membrane separation system: Ceramic membrane microfiltration is used to first remove colloidal, macromolecular impurities and some pigments from molasses, followed by desalination and concentration using nanofiltration membrane. By precisely controlling the operating parameters and introducing a specific ratio of dialysis water, the stage yield of betaine is greatly improved while efficiently removing impurities (microfiltration 99%, nanofiltration 97.5%). 2. Continuous chromatographic separation: Using a multi-column continuous chromatographic system at an optimized temperature of 75℃, water was used as the eluent to effectively separate betaine from residual sugars, ions, and other impurities, obtaining a high-purity betaine fraction solution. 3. Green process: Water is used as the main solvent throughout the process, avoiding the use of large amounts of organic solvents; the membrane separation process has relatively low energy consumption and generates less wastewater. Attached Figure Description
[0020] Figure 1 This is a flow chart of the betaine extraction process described in this invention; Figure 2This is a schematic diagram of a continuous chromatography system (showing the connection method of the 7 chromatographic columns and the material flow direction). Figure 3 The image shows the HPLC chromatogram of the betaine product obtained according to the method in Example 1. Figure 4 The image shows the HPLC chromatogram of the betaine product obtained according to the method in Example 2. Figure 5 The image shows the HPLC chromatogram of the betaine product obtained according to the method in Example 3. Detailed Implementation
[0021] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.
[0022] Example 1
[0023] Raw material pretreatment: Take 100kg of beet molasses (actual betaine content 7%, total sugar content 46%), add 180kg of pure water, and stir at a constant temperature of 55℃ for 30 minutes to fully dilute it.
[0024] Ceramic membrane microfiltration: The diluted feed solution was pumped into a microfiltration system equipped with an 80nm pore size ceramic membrane. The operating temperature was controlled at 55℃, the feed pressure at 0.22MPa, and the membrane flux was stabilized at 60LMH. Dialysis water, equivalent to 32% of the total feed volume, was added simultaneously. After microfiltration, the permeate was collected, and analysis showed that the betaine yield reached 99%.
[0025] Nanofiltration membrane purification: The microfiltration permeate is introduced into a nanofiltration system equipped with a 200 Da molecular weight cutoff nanofiltration membrane. The inlet pressure is controlled at 2.3 MPa, the flux at 18 LMH, and dialyzed water equivalent to 42% of the total microfiltration feed volume is added.
[0026] Continuous chromatographic separation: The nanofiltration retentate was pumped into a continuous chromatographic system consisting of 7 columns (packed with styrene-divinylbenzene cation exchange resin). The feed solution entered through column 7, and the eluent entered through column 1. The system temperature was controlled at 75°C. The betaine-rich fraction was collected from the outlet of column 3, with a purity of 96%, resulting in a yield of 93% for this stage.
[0027] Crystallization and drying: The collected betaine fraction was concentrated to a solid content of 70% under a vacuum of -0.085 MPa and a temperature of 68°C. The concentrate was then cooled to 18°C for crystallization, and allowed to stand for 12 hours. After crystallization, the mixture was centrifuged, and the resulting wet crystals were dried in a 60°C oven to constant weight to obtain a white crystalline betaine product.
[0028] Results analysis: Approximately 6.8 kg of betaine product was finally obtained. HPLC analysis showed that the purity reached 98.6%, and the total yield was calculated to be approximately 80.8%.
[0029] Example 2
[0030] Following the steps of Example 1, only the inlet pressure of the nanofiltration stage was adjusted to 2.0 MPa, the flux to 15 LMH, and dialysis water equivalent to 35% of the total volume of the microfiltrate feed was added.
[0031] Results: The purity of the final product, betaine, was approximately 98.2%, and the overall yield was approximately 79.5%.
[0032] Example 3
[0033] This embodiment uses a hydrophilic-charged modified ceramic membrane to solve the technical problems of severe membrane fouling and rapid flux decline in beet molasses solution during microfiltration, thereby improving the continuous operation stability and economy of the entire process.
[0034] Raw material pretreatment: Same as in Example 1, take 100kg of beet molasses, add 180kg of pure water, and stir and dilute in a 55℃ water bath for 30 minutes.
[0035] Ceramic membrane microfiltration (using hydrophilic-charged modified ceramic membrane): Membrane module: An alumina ceramic membrane with an average pore size of 80 nm is used. This membrane undergoes surface modification treatment to make it hydrophilic and negatively charged. The specific modification method is as follows: 1. Sol preparation: Tetraethyl orthosilicate (TEOS) is used as the silicon source precursor, anhydrous ethanol as the solvent, deionized water as the hydrolysate, and hydrochloric acid (HCl, 0.1 mol / L) as the catalyst. The molar ratio of each substance is TEOS : C2H5OH : H2O : HCl = 1 : 20 : 4 : 0.05. Triethyl phosphate (TEP) is added to the above mixture, and its molar ratio with TEOS is TEP : TEOS = 1 : 20. The mixture is magnetically stirred and refluxed in a 60℃ water bath for 4 hours to form a stable and transparent SiO2-P2O5 composite sol. 2. Membrane Pretreatment: The ceramic membrane is first soaked in 0.5 mol / L NaOH solution for 30 minutes, then rinsed with deionized water until neutral, and dried at 110℃ for later use. 3. Coating Process: The pretreated ceramic membrane is vertically immersed in the composite sol described above. After soaking for 1 minute, it is pulled out of the liquid surface at a constant speed of 2 mm / s. 4. Gel and Heat Treatment: The wet membrane is allowed to stand at room temperature for 30 minutes to allow the solvent to evaporate and the sol to gel. Then, it is placed in a muffle furnace for programmed temperature calcination: the temperature is increased to 120℃ at 1℃ / min and held for 30 minutes to completely remove the organic solvent; then the temperature is increased to 450℃ at 2℃ / min and held for 2 hours. After natural cooling, a uniform and firm SiO2-P2O5 composite modified layer is formed on the surface of the ceramic membrane.
[0036] Operating procedure: The pretreated diluted feed solution is pumped into the hydrophilic-charged modified ceramic membrane microfiltration system described above. The operating temperature is controlled at 55℃, the feed pressure at 0.22MPa, and the membrane flux is stabilized at 80LMH. Dialysis water, equivalent to 32% of the total feed volume, is added simultaneously. After microfiltration, the permeate is collected.
[0037] Subsequent steps: The specific operating conditions and parameters for nanofiltration membrane purification, continuous chromatographic separation, crystallization and drying steps are consistent with those in Example 1.
[0038] Results analysis: HPLC analysis showed that the purity of the final product, betaine, was 99.3%, and the total yield was 87.5%. Compared to using ordinary ceramic membranes, this embodiment maintains high yield and high purity while significantly improving the throughput and stability of the microfiltration unit, reducing membrane cleaning frequency, and making it more suitable for large-scale continuous production.
[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for extracting betaine from beet molasses, characterized in that, Includes the following steps: (1) Raw material pretreatment: Dilute beet molasses with water; (2) Ceramic membrane microfiltration: The diluted solution obtained in step (1) is subjected to ceramic membrane microfiltration treatment, and the permeate is collected; (3) Nanofiltration membrane purification: The permeate obtained in step (2) is subjected to nanofiltration treatment, and the retentate is collected; (4) Continuous chromatographic separation: The nanofiltration retentate obtained in step (3) is passed into a continuous chromatographic system composed of multiple chromatographic columns for separation, and the component solution rich in betaine is collected; (5) Crystallization and drying: The betaine-rich component solution obtained in step (4) is concentrated, crystallized, separated and dried to obtain the betaine product.
2. The method according to claim 1, characterized in that, In step (1), the water is pure water, and the weight ratio of the pure water to beet molasses is (1.5-2.0):
1.
3. The method according to claim 1, characterized in that, In step (2), the operating conditions for the ceramic membrane microfiltration are as follows: a ceramic membrane with a pore size of 80 nm is used, the operating temperature is 55-60℃, the feed pressure is 0.22-0.23 MPa, and dialysis water equivalent to 30%-35% of the total feed volume is added.
4. The method according to claim 1, characterized in that, In step (3), the operating conditions for nanofiltration membrane purification are as follows: a nanofiltration membrane with a molecular weight cutoff of 200 Da is used, the inlet pressure is 2.0-2.3 MPa, and dialysis water equivalent to 35%-42% of the total feed volume of the microfiltration permeate is added.
5. The method according to claim 1, characterized in that, In step (4), the continuous chromatography system consists of 7 columns, which are filled with styrene-divinylbenzene cation exchange resin; the feed solution enters from the 7th column, the elution water enters from the 1st column, the system temperature is 75°C, and the component solution rich in betaine is collected from the outlet of the 3rd column.
6. The method according to claim 1, characterized in that, In step (5), the concentration is carried out under vacuum conditions, with a vacuum degree of -0.08 to -0.09 MPa and a temperature of 65–70°C; the crystallization is carried out by cooling the concentrate to 18°C and allowing it to stand for crystallization; the drying temperature is 60°C.
7. The method according to claim 1, characterized in that, In step (2), the ceramic membrane is a ceramic membrane that has undergone hydrophilic modification and charge modification.
8. The method according to claim 7, characterized in that, The hydrophilic modification and charge modification are achieved by forming a SiO2-P2O5 composite modification layer on the surface of the ceramic film through a sol-gel coating method.
9. The method according to claim 8, characterized in that, The preparation of the sol includes: mixing tetraethyl orthosilicate, anhydrous ethanol, deionized water and hydrochloric acid in a molar ratio of 1:20:4:0.05, adding triethyl phosphate in a molar ratio of 1:20 to tetraethyl orthosilicate, and refluxing and stirring at 60°C for 4 hours to form a composite sol.
10. The method according to any one of claims 1-9, characterized in that, The final betaine product has a purity of not less than 98% and a total yield of not less than 80%.