AU2020103781A4 - Method for efficiently preparing policosanol from insect wax - Google Patents

Abstract

The present invention discloses a method for efficiently preparing policosanol from Insect wax. The method comprises: making a reducing agent react with Insect wax under normal pressure so that 1 mole of Insect wax produces 2 moles of policosanol, wherein Insect wax: the reduction Agent=1:0.05-0.3 (mass ratio g:g); after the reaction is ended, adding a cosolvent and water to generate a hydrolysis reaction, wherein the reactant Insect wax: the cosolvent: the water--1:2-5:0.5-3 (mass/volume/volume ratio, g:nL:nL); then, removing water-soluble reduction products by washing, and meanwhile, precipitating water-insoluble reduction products at the bottom and filtering out the precipitate; pickling to adjust the pH value to neutral; transforming the precipitate into soluble substances; and washing the soluble substances with water to obtain a policosanol mixture product. The technology is good in coherence, easy in operation, environmental-friendly and high in yield in industrial production. Drawings of Description Reduction reaction of Insect wax Hydrolysis reaction of reduction product Solvent recovery Washing Pickling Washing Fig. 1 Process Flow Chart 9

Description

Drawings of Description

Reduction reaction of Insect wax

Hydrolysis reaction of reduction product

Solvent recovery

Washing

Pickling

Washing

Fig. 1 Process Flow Chart

Description METHOD FOR EFFICIENTLY PREPARING POLICOSANOL FROM INSECT WAX Technical Field The present invention relates to the technical field of chemical industry, and particularly relates to a method for efficiently preparing policosanol from Insect wax. Background Policosanol, also known as higher aliphatic alcohol, is chained saturated monohydric alcohol containing more than twelve carbon atoms. The policosanol exists extremely widely in nature, but hardly exists as natural free aliphatic alcohol, and generally exists in all organisms in the form of wax ester. The wax esters rich in the policosanol include: rice bran wax, sugarcane wax, sorghum wax, Insect wax, beeswax, carnauba wax, sunflower wax, shellac wax and wool wax. The policosanol has important physiological activities and good market prospects so that the policosanol is developed and utilized as a natural product to become a popular field for research in fine chemistry, medicine and agriculture. At present, the research hotspot of the policosanol in China and abroad is the research on preparation, separation and utilization technologies of C22-C36 mixed alcohols. At present, the main methods for preparing policosanol mixture from natural biological wax include: (1) The wax is saponified and decomposed under alkaline conditions, and fatty acid salt is removed to obtain the policosanol mixture. (2) The wax generates a transesterification reaction through alcoholysis. Different products are separated by vacuum distillation according to different boiling points of the reaction products, so as to obtain the policosanol mixture. (3) The wax is directly reduced to fatty alcohol by a reducing agent. For example, under certain conditions, lithium aluminum hydride is used as the reducing agent to directly reduce one mole of Insect wax to two moles of policosanol. (4) The wax is hydrolyzed under acidic conditions, and then the fatty alcohol is leached by supercritical fluid. (5) The wax is decomposed by an enzyme to extract the fatty alcohol. The reduction method can reduce one mole of wax to two moles of policosanol. Therefore, in the above methods, the reduction method has the highest product yield and can efficiently use the biological wax raw materials. Patent 200810058584.2 discloses a method for preparing policosanol mixture from Insect wax, which has the characteristic that Insect wax is reduced with a reducing agent in an organic solvent to prepare policosanol and the disadvantage that the production cost is increased due to the use of the solvent. Patent 200810058866.2 improves the technology of preparing policosanol from Insect wax by a reduction method. No organic solvent is used in the reduction reaction process, which reduces the cost. However, the policosanol product has low purity and unreliable quality. The post-treatment technology of the reduction reaction is required to be improved. Summary The purpose of the present invention is to provide a method for preparing policosanol mixture having low cost, simple technology, high efficiency, high purity and good product quality. The present invention adopts the following technical solution: A method for efficiently preparing policosanol from Insect wax in the present invention comprises the following specific steps: A: reduction reaction: weighing Insect wax into a reactor; adding a reducing agent to the reactor, wherein a mass ratio is: Insect wax: reducing agent=1:0.05-0.3; heating the mixture with an oil bath to make the mixture react, wherein the temperature of the oil bath is 100 150°C and reaction time is 20-40 min; B: dissolution and hydrolysis reaction of the reaction mixture: in the reaction system obtained in step A, according to the reactant Insect wax: a cosolvent: water = 1:2-5:0.5-3 (mass/volume/volume ratio, g:mL:mL), adding the cosolvent and the water; heating the mixture system to reflux for 10-30 min, wherein reflux temperature is 50-100°C; C: solvent recovery: stopping the reflux process of step B; replacing a condenser tube; installing a condensation and recovery device; continuing to heat; and recovering a solvent to obtain a reaction mixture without the cosolvent; D: washing: after the solvent is recovered, adding water to the reaction mixture obtained in step C according to the Insect wax: water--1:5-10 (mass/volume ratio, g: mL); heating and refluxing for 5-10 min; and after cooling, separating the upper layer of policosanol mixture from the lower layer of washing liquid, wherein the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered; E: pickling: adding hydrochloric acid with a mass fraction of 10-30% to the policosanol mixture obtained in step D, wherein the adding amount is: Insect wax: hydrochloric acid=1:1 3 (mass/volume ratio, g:mL); adjusting the pH of the mixture system to neutral; heating and refluxing for 10-20 min; and after cooling, separating the upper layer of policosanol mixture and the lower layer of water; F: washing: adding water to the policosanol mixture obtained in step E according to the Insect wax: water=1:5-10 (mass/volume ratio, g:mL); heating and refluxing for 10-20 min;

/A and after cooling, separating the upper layer of policosanol from the lower layer of water to obtain a policosanol mixture product; G: wastewater treatment: heating the washing water, produced in step D, containing reduction products with high water solubility to evaporate the water; and recycling the remaining solid, wherein the wastewater of step E and step F contains fewer residues, which meets emission standards. In step A, the reducing agent is powdered lithium aluminum hydride or granular lithium aluminum hydride which is a commercial product. In step A, preferably, the Insect wax: reducing agent=1:0.2; the temperature of the oil bath is 120°C; and the reaction time is 30 min. In step B, the cosolvent is one of ethanol, acetone, dichloromethane, chloroform or ethyl acetate. In step B, preferably, according to the reactant Insect wax: the cosolvent: water = 1:3:2 (mass/volume/volume ratio, g:L:L), the cosolvent and the water are added; and the mixture system is heated to reflux for 20 min, wherein reflux temperature is 80°C. In step D, preferably, the water is added to the reaction mixture obtained in step C according to the Insect wax: water=1: 8 (mass/volume ratio, g: mL), and the mixture is heated and refluxed for 8 min. In step E, preferably, the adding amount of hydrochloric acid is: the Insect wax: hydrochloric acid=1:2 (mass/volume ratio, g: mL); the pH value of the mixture system is adjusted to neutral; and the mixture is heated and refluxed for 15 min. In step F, preferably, water is added to the policosanol mixture obtained in step E according to the Insect wax: water--1:8 (mass/volume ratio, g:nL); and the mixture is heated and refluxed for 15 min. The water is tap water. The present invention has the following positive effects that: The method for efficiently preparing policosanol from Insect wax in the present invention enables the reduction reaction to maintain a relatively mild reaction rate after the reaction activation energy is reached, is easy to control, and reduces the requirements and cost of production equipment. The whole technological process is simple and compact, convenient to operate, high in reaction conversion rate and fewer in side reactions. The obtained policosanol mixture has high purity, stable quality, less three wastes, and easy industrial production. The product yield of the policosanol mixture (mixture composition: tetracosanol, hexacosanol, octacosanol and triacontanol) obtained by the method of the present invention is up to 85-95%, which is much higher than the 20-30% yield of a saponification method. Description of Drawings Fig. 1 is a process flow chart of the present invention.

Detailed Description The present invention will be further described below in combination with specific embodiments. Embodiment 1 A: lOg of Insect wax is weighed into a reactor; 0.5g of reducing agent of powdered lithium aluminum hydride is added to the reactor; the mixture is heated in an oil bath at100°C; after 20 min, the reaction is ended, to form a large amount of foam. B: In the reaction system obtained in step A, 20 mL of cosolvent ethanol and 5 mL of water are added to reflux at 700 C for 10 min. C: After the mixture is refluxed in step B, a condensation and recovery device is installed; heating is continued; and the ethanol is recovered to obtain a reaction mixture without the cosolvent. D: In the mixture obtained in step C, 50 mL of water is added to reflux for 5 min; after cooling, the upper layer of policosanol mixture is separated from the lower layer of washing liquid; the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered. E: 10 mL of 10% hydrochloric acid is added to the policosanol mixture obtained in step D; at this moment, the pH value of the mixture system is neutral; the mixture system is heated and refluxed for 10 min; and after cooling, the upper layer of policosanol mixture is separated from the lower layer of water. F: 50 mL of water is added to the policosanol mixture obtained in step E; the mixture is heated and refluxed for 10 min; and after cooling, the upper layer of policosanol is separated from the lower layer of water to obtain a policosanol mixture (mixture composition: tetracosanol, hexacosanol, octacosanol and triacontanol) product. The yield of the policosanol is up to 88%, which is much higher than the 20-30% yield of a saponification method. G: Wastewater treatment: the washing water, produced in step D, containing reduction products with high water solubility is heated to evaporate the water; and the remaining solid is recycled. Embodiment 2 A: 100g of Insect wax is weighed into a reactor; 30g of reducing agent of granular lithium aluminum hydride is added to the reactor; the mixture is heated in an oil bath at 1500 C to react; the reaction time is 30min. B: In the reaction system obtained in step A, 300 mL of cosolvent chloroform and 100 mL of water are added; and the mixture system is heated to 500 C to reflux for 20 min. C: The reflux process of step B is stopped; a condenser tube is replaced; a condensation and recovery device is installed; heating is continued; and the solvent chloroform is recovered to obtain a reaction mixture without the cosolvent.

D: After the solvent is recovered, in the reaction mixture obtained in step C, 800 mL of water is added; the reaction mixture is heated to reflux for 8 min; after cooling, the upper layer of policosanol mixture is separated from the lower layer of washing liquid; the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered. E: 200 mL of 20% hydrochloric acid is added to the policosanol mixture obtained in step D; the mixture system is heated and refluxed for 15 min; and after cooling, the upper layer of policosanol mixture is separated from the lower layer of water. F: 800 mL of water is added to the policosanol mixture obtained in step E; the mixture is heated and refluxed for 15 min; and after cooling, the upper layer of policosanol is separated from the lower layer of water to obtain a policosanol mixture (mixture composition: tetracosanol, hexacosanol, octacosanol and triacontanol) product. The yield of the policosanol is up to 90%, which is much higher than the 20-30% yield of a saponification method. G: Wastewater treatment: the washing water, produced in step D, containing reduction products with high water solubility is heated to evaporate the water; and the remaining solid is recycled. Embodiment 3 A: lkg of Insect wax is weighed into a reactor; 300g of reducing agent of granular lithium aluminum hydride is added to the reactor; the mixture is heated in an oil bath to react; the temperature of the oil bath is 150°C; and the reaction time is 40min. B: In the reaction system obtained in step A, 5L of cosolvent ethyl acetate and 3L of water are added; and the mixture system is heated to 70°C to reflux for 30 min. C: The reflux process of step B is stopped; a condenser tube is replaced; a condensation and recovery device is installed; heating is continued at 70°C; and the solvent ethyl acetate is recovered to obtain a reaction mixture without the cosolvent. D: After the solvent is recovered, in the reaction mixture obtained in step C, 10L of water is added; the reaction mixture is heated to reflux for 10 min; after cooling, the upper layer of policosanol mixture is separated from the lower layer of washing liquid; the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered. E: 3 L of 30% hydrochloric acid is added to the policosanol mixture obtained in step D; the mixture system is heated and refluxed for 20 min; and after cooling, the upper layer of policosanol mixture is separated from the lower layer of water. F: 10L of water is added to the policosanol mixture obtained in step E; the mixture is heated and refluxed for 20 min; and after cooling, the upper layer of policosanol is separated from the lower layer of water to obtain a policosanol mixture (mixture composition: tetracosanol, hexacosanol, octacosanol and triacontanol) product. The yield of the policosanol is up to 92%, which is much higher than the 20-30% yield of a saponification method. G: The washing water, produced in step D, containing reduction products with high water solubility is heated to evaporate the water; and the remaining solid is recycled. The wastewater of step E and step F contains fewer residues, which meets emission standards and is directly discharged. Embodiment 4 A: 1Og of Insect wax is weighed into a reactor; 2g of reducing agent of powdered lithium aluminum hydride is added to the reactor; the mixture is heated in an oil bath at 120°C; after min, the reaction is ended, to form a large amount of foam. B: In the reaction system obtained in step A, 30 mL of cosolvent ethanol and 20 mL of water are added to reflux at 80°C for 20 min. C: After the mixture is refluxed in step B, a condensation and recovery device is installed; heating is continued; and the ethanol is recovered to obtain a reaction mixture without the cosolvent. D: In the mixture obtained in step C, 80 mL of water is added to reflux for 8 min; after cooling, the upper layer of policosanol mixture is separated from the lower layer of washing liquid; the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered. E: 20 mL of 10% hydrochloric acid is added to the policosanol mixture obtained in step D; at this moment, the pH value of the mixture system is neutral; the mixture system is heated and refluxed for 15 min; and after cooling, the upper layer of policosanol mixture is separated from the lower layer of water. F: 80 mL of water is added to the policosanol mixture obtained in step E; the mixture is heated and refluxed for 15 min; and after cooling, the upper layer of policosanol is separated from the lower layer of water to obtain a policosanol mixture (mixture composition: tetracosanol, hexacosanol, octacosanol and triacontanol) product. The yield of the policosanol is up to 95%, which is much higher than the 20-30% yield of a saponification method. G: Wastewater treatment: the washing water, produced in step D, containing reduction products with high water solubility is heated to evaporate the water; and the remaining solid is recycled. Although the embodiments of the present invention have been shown and described, it will be appreciated that various variations, amendments, replacements and modifications can be made by those ordinary skilled in the art without departing from the principle and spirit of the present invention, and the scope of the present invention is limited by the appended claims and the equivalent thereof.

Claims (5)

1. Claims 1. A method for efficiently preparing policosanol from Insect wax, comprising the following specific steps: A: reduction reaction: weighing Insect wax into a reactor; adding a reducing agent to the reactor, wherein a mass ratio is: Insect wax: reducing agent=1:0.05-0.3; heating the mixture with an oil bath to make the mixture react, wherein the temperature of the oil bath is 100 150°C and reaction time is 20-40 min; B: dissolution and hydrolysis reaction of the reaction mixture: in the reaction system obtained in step A, according to the reactant Insect wax: a cosolvent: water = 1:2-5:0.5-3 (mass/volume/volume ratio, g:L:L), adding the cosolvent and the water; heating the mixture system to reflux for 10-30 min, wherein reflux temperature is 50-100°C; C: solvent recovery: stopping the reflux process of step B; replacing a condenser tube; installing a condensation and recovery device; continuing to heat; and recovering a solvent to obtain a reaction mixture without the cosolvent; D: washing: after the solvent is recovered, adding water to the reaction mixture obtained in step C according to the Insect wax: water--1:5-10 (mass/volume ratio, g: mL); heating and refluxing for 5-10 min; and after cooling, separating the upper layer of policosanol mixture from the lower layer of washing liquid, wherein the precipitate at the bottom of the washing liquid is aluminum hydroxide and is filtered and recovered; E: pickling: adding hydrochloric acid with a mass fraction of 10-30% to the policosanol mixture obtained in step D, wherein the adding amount is: Insect wax: hydrochloric acid=1:1 3 (mass/volume ratio, g:nL); adjusting the pH of the mixture system to neutral; heating and refluxing for 10-20 min; and after cooling, separating the upper layer of policosanol mixture and the lower layer of water; F: washing: adding water to the policosanol mixture obtained in step E according to the Insect wax: water=1:5-10 (mass/volume ratio, g:nL); heating and refluxing for 10-20 min; and after cooling, separating the upper layer of policosanol from the lower layer of water to obtain a policosanol mixture product; G: wastewater treatment: heating the washing water, produced in step D, containing reduction products with high water solubility to evaporate the water; and recycling the remaining solid, wherein the wastewater of step E and step F contains fewer residues, which meets emission standards.
2. 2. The method for efficiently preparing policosanol from Insect wax according to claim 1, wherein in step A, the reducing agent is powdered lithium aluminum hydride or granular lithium aluminum hydride; the Insect wax: reducing agent=1:0.2; the temperature of the oil bath is 120°C; and the reaction time is 30 min.
3. 3. The method for efficiently preparing policosanol from Insect wax according to claim 1, wherein in step B, the cosolvent is one of ethanol, acetone, dichloromethane, chloroform or ethyl acetate; according to the reactant Insect wax: the cosolvent: water = 1:3:2 (mass/volume/volume ratio, g:L:L), the cosolvent and the water are added; and the mixture system is heated to reflux for 20 min, wherein reflux temperature is 80°C.
4. 4. The method for efficiently preparing policosanol from Insect wax according to claim 1, wherein in step D, the water is added to the reaction mixture obtained in step C according to the Insect wax: water--1: 8 (mass/volume ratio, g: mL), and the mixture is heated and refluxed for 8 min.
5. 5. The method for efficiently preparing policosanol from Insect wax according to claim 1, wherein in step E, the adding amount of hydrochloric acid is: the Insect wax: hydrochloric acid=1:2 (mass/volume ratio, g: mL); the pH value of the mixture system is adjusted to neutral; and the mixture is heated and refluxed for 15 min.