High-purity glycerol refining method and special equipment
By pretreating lime milk suspension and potassium aluminum sulfate dodecahydrate solution combined with vacuum distillation and decolorization and deodorization, the problems of complexity and high cost of traditional glycerol purification methods were solved, and the preparation of efficient and high-purity glycerol was achieved.
Patent Information
- Application Number
- CN202510638743.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-19
- Publication Date
- 2025-10-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
In the existing technology, the traditional multi-stage distillation method is complex and costly, while the ion exchange resin method requires a large amount of heat source, resulting in high cost and low efficiency of glycerol purification.
Crude glycerin is pretreated with lime milk suspension and aluminum potassium sulfate dodecahydrate solution, combined with vacuum distillation and decolorization and deodorization treatment, and a mixed filtration device is used to achieve integrated mixing and filtration to improve efficiency.
The preparation of high-purity glycerol (purity > 99.8%) is achieved, which reduces the space occupied by equipment and improves the refining efficiency and safety.
Smart Images
Figure CN120757439A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of glycerol refining, in particular to a high-purity glycerol refining method and special equipment. Background Art
[0002] Pure glycerin is a colorless, sweet, viscous liquid. It is a triol with the general chemical properties of triols and can participate in many chemical reactions to produce various derivatives. Due to its many important physical and chemical properties, glycerin has become an important chemical raw material. In my country, glycerin is currently used primarily in the production of coatings, salt, medicine, toothpaste, cellophane, and insulation materials.
[0003] Crude glycerin purification primarily involves ion exchange resins and traditional multi-stage distillation. The traditional multi-stage distillation method suffers from complex distillation processes and high costs. While the ion exchange resin method offers mild operating conditions, it consumes significant amounts of heat for concentration. Therefore, a high-purity glycerin purification method and dedicated equipment are proposed. Summary of the Invention
[0004] In view of the shortcomings of the existing technology, the present invention provides a high-purity glycerol refining method and special equipment. The purity of the obtained glycerol is greater than 99.8%, which is conducive to the safe application of glycerol.
[0005] To achieve the above object, the present invention provides the following technical solution: a method for refining high-purity glycerol and dedicated equipment, comprising the following steps:
[0006] (1) injecting the crude glycerin and lime milk suspension into a first mixing and filtration device, mixing and reacting, and then filtering and separating to obtain a crude liquid;
[0007] (2) injecting the coarse material liquid and the potassium aluminum sulfate dodecahydrate solution into the second mixing and filtration device, mixing and reacting, and then filtering and separating to obtain the fine material liquid;
[0008] (3) The fine material liquid is pumped into a vacuum distillation device for dehydration and impurity removal, and then the distillation product is pumped into a decolorization and deodorization device. After the refining is completed, high-purity glycerin is obtained.
[0009] Preferably, in step (1), the lime milk suspension is made of quicklime and distilled water, wherein the quicklime accounts for 0.15-0.2% of the mass of the crude glycerol.
[0010] Preferably, in step (1), the mixing reaction temperature is 75-85° C., and the mixing reaction time is 15-20 min.
[0011] Preferably, in step (2), the potassium aluminum sulfate dodecahydrate solution is prepared from potassium aluminum sulfate dodecahydrate and distilled water, wherein the potassium aluminum sulfate dodecahydrate accounts for 5-6% of the mass of the crude glycerol.
[0012] Preferably, in step (2), the mixing reaction temperature is 80-85° C., and the mixing reaction time is 35-45 min.
[0013] Preferably, in step (3), in the reduced pressure distillation apparatus, the vacuum degree is controlled to be 105-115 Pa and the temperature is controlled to be 105-110°C.
[0014] Preferably, in step (3), the fillers used in the decolorization and deodorization device are activated carbon and molecular sieve.
[0015] The present invention also provides a special device for refining high-purity glycerol, including a kettle body, which is separated into a mixing chamber and a purification chamber. A suction filter pipe is installed between the mixing chamber and the purification chamber, and an electromagnetic valve is installed at the end of the suction filter pipe. A stirring element is installed in the mixing chamber, and a main feed pipe and an auxiliary feed pipe are installed in communication with the mixing chamber respectively, and a discharge pipe is installed in communication with the purification chamber. A cylinder is fixed at the outer end of the kettle body, and an exhaust pipe and a gas filling pipe with a one-way valve are installed in communication with the end of the cylinder. The exhaust pipe is installed in communication with the purification chamber, and the gas filling pipe is installed in communication with the mixing chamber. A piston and an electric push rod for driving the piston are installed in the cylinder.
[0016] Preferably, the stirring member includes a rotating shaft rotatably mounted on the kettle body, and a motor driving the rotating shaft to rotate, and the end of the rotating shaft extends into the mixing chamber and is fixed with a stirring blade.
[0017] The present invention provides a high-purity glycerin refining method and dedicated equipment, which have the following beneficial effects compared with the prior art:
[0018] The invention adopts lime milk suspension to remove sulfuric acid, fatty acids and esters in crude glycerin, adopts potassium aluminum sulfate dodecahydrate to remove residual lime, and simultaneously utilizes flocculation effect to destroy the colloid stability in the feed liquid to remove colloid. Then, the invention undergoes vacuum distillation and deodorization and decolorization treatment. The purity of the obtained glycerin is greater than 99.8%, which is conducive to the safe application of glycerin.
[0019] The special equipment used in the present invention, namely the mixing and filtration device, can realize the integration of mixing and filtration, reduce the space occupied by the equipment, and when the purification chamber is sucked into negative pressure, the mixing chamber can also be pressurized, thereby accelerating the filtration speed and improving the refining efficiency of glycerol. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0021] Figure 1 This is a process flow chart of the high-purity glycerin refining process of the present invention;
[0022] Figure 2 This is a schematic diagram of the structure of the special equipment for refining high-purity glycerol of the present invention.
[0023] In the figure: 1- kettle body, 2- mixing chamber, 3- purification chamber, 4- main feed pipe, 5- auxiliary feed pipe, 6- discharge pipe, 7- stirring element, 8- suction pipe, 9- electromagnetic valve, 10- cylinder, 11- piston, 12- electric push rod, 13- exhaust pipe, 14- gas filling pipe. DETAILED DESCRIPTION
[0024] The following examples illustrate the implementation methods of the present application in detail, so that the implementation process of how the present application applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0025] Example 1
[0026] A special device for refining high-purity glycerin includes a first mixing and filtering device and a second mixing and filtering device. The special device comprises a kettle body 1, an inner wall interlayer of which is installed with a heating wire installed at the position of a mixing chamber 2. The kettle body 1 is divided into a mixing chamber 2 and a purification chamber 3. A suction filter tube 8 is installed in communication between the mixing chamber 2 and the purification chamber 3, and a suction filter plate 9 is installed at the end of the suction filter tube 8. A stirring element 7 is installed in the mixing chamber 2, and a main feed pipe 4 and a secondary feed pipe 5 are installed in communication with the mixing chamber 2, respectively. A discharge pipe 6 is installed in communication with the purification chamber 3. A cylinder 10 is fixed to the outer end of the kettle body 1, and an exhaust pipe 13 with a one-way valve and an air supply pipe 14 are installed at the end of the cylinder 10. The exhaust pipe 13 is installed in communication with the purification chamber 3, and the air supply pipe 14 is installed in communication with the mixing chamber 2. A piston 11 and an electric push rod 12 for driving the piston 11 are installed in the cylinder 10. The stirring member 7 includes a rotating shaft rotatably mounted on the kettle body 1 and a motor driving the rotating shaft to rotate. The end of the rotating shaft extends into the mixing chamber 2 and is fixed with a stirring blade.
[0027] Take the use of crude glycerin and lime milk suspension as an example: crude glycerin is injected from the main feed pipe 4, and lime milk suspension is injected from the auxiliary feed pipe 5. Then the motor is started, and the stirring blade is driven by the rotating shaft to rotate to mix the two. After the reaction is completed, the solenoid valve is opened, and the reaction liquid slowly falls from the mixing chamber 2 into the purification chamber 3. At the same time, the electric push rod 12 is controlled to drive the piston 11 to move back and forth along the cylinder 10. When the piston 11 moves up, the one-way valve on the exhaust pipe 13 opens, and the air in the purification chamber 3 is sucked into the cylinder 10. The purification chamber 3 is in a negative pressure state and filtration begins. When the piston 11 moves down, the one-way valve on the air supply pipe 14 opens, and the air in the cylinder 10 enters the mixing chamber 2 through the air supply pipe 14. The pressure in the mixing chamber 2 rises, pressurizing the reaction liquid, which is conducive to the rapid filtration of the reaction liquid. The filtered crude liquid can flow out from the discharge pipe 6.
[0028] Example 2
[0029] A method for refining high-purity glycerol comprises the following steps:
[0030] (1) injecting the crude glycerin and lime milk suspension into a No. 1 mixing and filtration device, mixing and reacting at 75°C for 20 minutes, and then filtering and separating to obtain a crude liquid;
[0031] The main components of crude glycerin include: 85.5wt% glycerin, 13.8% water, 0.1% soap, and the remainder is other impurities.
[0032] The above-mentioned lime milk suspension is made of quicklime and distilled water, wherein the quicklime accounts for 0.15% of the mass of crude glycerol.
[0033] (2) injecting the coarse material liquid and the potassium aluminum sulfate dodecahydrate solution into the second mixed filtration device, mixing and reacting at 85°C for 35 minutes, and then filtering and separating to obtain the fine material liquid;
[0034] The potassium aluminum sulfate dodecahydrate solution is prepared from potassium aluminum sulfate dodecahydrate and distilled water, wherein the potassium aluminum sulfate dodecahydrate accounts for 6% of the mass of the crude glycerol.
[0035] (3) The fine material liquid is pumped into a vacuum distillation device for dehydration and impurity removal, during which the vacuum degree is controlled at 115 Pa and the temperature is 110°C. The distilled product is then pumped into a decolorization and deodorization device (the fillers used are activated carbon and molecular sieves). After the refining is completed, high-purity glycerin is obtained.
[0036] Example 3
[0037] A method for refining high-purity glycerol comprises the following steps:
[0038] (1) injecting the crude glycerin and lime milk suspension into a No. 1 mixing and filtration device, mixing and reacting at 85°C for 15 minutes, and then filtering and separating to obtain a crude liquid;
[0039] The main components of crude glycerin include: 85.5wt% glycerin, 13.8% water, 0.1% soap, and the remainder is other impurities.
[0040] The above-mentioned lime milk suspension is made of quicklime and distilled water, wherein the quicklime accounts for 0.2% of the mass of crude glycerol.
[0041] (2) injecting the coarse material liquid and the potassium aluminum sulfate dodecahydrate solution into the second mixed filtration device, mixing and reacting at 80°C for 45 minutes, and then filtering and separating to obtain the fine material liquid;
[0042] The potassium aluminum sulfate dodecahydrate solution is prepared from potassium aluminum sulfate dodecahydrate and distilled water, wherein the potassium aluminum sulfate dodecahydrate accounts for 5% of the mass of the crude glycerol.
[0043] (3) The fine liquid is pumped into a vacuum distillation device for dehydration and impurity removal, during which the vacuum degree is controlled at 105 Pa and the temperature is 105°C. The distilled product is then pumped into a decolorization and deodorization device (the fillers used are activated carbon and molecular sieves). After the refining is completed, high-purity glycerin is obtained.
[0044] Example 4
[0045] A method for refining high-purity glycerol comprises the following steps:
[0046] (1) injecting the crude glycerin and lime milk suspension into a No. 1 mixing and filtration device, mixing and reacting at 80°C for 20 minutes, and then filtering and separating to obtain a crude liquid;
[0047] The main components of crude glycerin include: 85.5wt% glycerin, 13.8% water, 0.1% soap, and the remainder is other impurities.
[0048] The above-mentioned lime milk suspension is made of quicklime and distilled water, wherein the quicklime accounts for 0.2% of the mass of crude glycerol.
[0049] (2) injecting the coarse material liquid and the potassium aluminum sulfate dodecahydrate solution into the second mixed filtration device, mixing and reacting at 85°C for 40 minutes, and then filtering and separating to obtain the fine material liquid;
[0050] The potassium aluminum sulfate dodecahydrate solution is prepared from potassium aluminum sulfate dodecahydrate and distilled water, wherein the potassium aluminum sulfate dodecahydrate accounts for 5.5% of the mass of the crude glycerol.
[0051] (3) The fine liquid is pumped into a vacuum distillation device for dehydration and impurity removal, during which the vacuum degree is controlled at 110 Pa and the temperature is 110°C. The distilled product is then pumped into a decolorization and deodorization device (the fillers used are activated carbon and molecular sieves). After the refining is completed, high-purity glycerin is obtained.
[0052] Ingredient testing
[0053] 1. According to the test method for glycerol impurities (GC) in the "Chinese Pharmacopoeia Volume 4 2020 Edition", the high-purity glycerol in Example 2-4 was tested.
[0054] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.
Claims
1. A method for refining high-purity glycerol, characterized in that: The following steps are involved: (1) Injecting the crude glycerin and lime milk suspension into the No. 1 mixing and filtration device, mixing and reacting, and then filtering and separating to obtain a crude liquid; (2) injecting the coarse material liquid and the potassium aluminum sulfate dodecahydrate solution into the second mixed filtration device, mixing and reacting, and then filtering and separating to obtain the fine material liquid; (3) The fine material liquid is pumped into a vacuum distillation device for dehydration and impurity removal, and then the distillation product is pumped into a decolorization and deodorization device. After the refining is completed, high-purity glycerin is obtained.
2. The method for refining high-purity glycerin according to claim 1, wherein: In step (1), the lime milk suspension is made of quicklime and distilled water, wherein the quicklime accounts for 0.15-0.2% of the mass of the crude glycerol.
3. The method for refining high-purity glycerin according to claim 1, wherein: In step (1), the mixing reaction temperature is 75-85° C., and the mixing reaction time is 15-20 min.
4. The method for refining high-purity glycerin according to claim 1, wherein: In step (2), the potassium aluminum sulfate dodecahydrate solution is prepared from potassium aluminum sulfate dodecahydrate and distilled water, wherein the potassium aluminum sulfate dodecahydrate accounts for 5-6% of the mass of the crude glycerol.
5. The method for refining high-purity glycerin according to claim 1, wherein: In step (2), the mixing reaction temperature is 80-85° C., and the mixing reaction time is 35-45 min.
6. The method for refining high-purity glycerin according to claim 1, wherein: In step (3), in the reduced pressure distillation apparatus, the vacuum degree is controlled to be 105-115 Pa and the temperature is controlled to be 105-110°C.
7. The method for refining high-purity glycerin according to claim 1, wherein: In step (3), the fillers used in the decolorization and deodorization device are activated carbon and molecular sieve.
8. The method for refining high-purity glycerin according to claim 1, wherein: A special device for refining high-purity glycerol is used, comprising a kettle body (1), wherein a mixing chamber (2) and a purification chamber (3) are separated in the kettle body (1), a suction filter tube (8) is installed between the mixing chamber (2) and the purification chamber (3), a solenoid valve (9) is installed at the end of the suction filter tube (8), a stirring element (7) is installed in the mixing chamber (2), a main feed tube (4) and a secondary feed tube (5) are installed in the mixing chamber (2), and a discharge tube (6) is installed in the purification chamber (3), a cylinder (10) is fixed at the outer end of the kettle body (1), an air extraction tube (13) with a one-way valve and an air supply tube (14) are installed in the end of the cylinder (10), the air extraction tube (13) is installed in communication with the purification chamber (3), and the air supply tube (14) is installed in communication with the mixing chamber (2), a piston (11) and an electric push rod (12) for driving the piston (11) are installed in the cylinder (10).
9. The method for refining high-purity glycerin according to claim 8, characterized in that: The stirring member (7) comprises a rotating shaft rotatably mounted on the kettle body (1), and a motor driving the rotating shaft to rotate. The end of the rotating shaft extends into the mixing chamber (2) and is fixed with a stirring blade.