CN117986224A - Refining method of high-purity DMDO (digital media do) - Google Patents
Refining method of high-purity DMDO (digital media do) Download PDFInfo
- Publication number
- CN117986224A CN117986224A CN202410148823.2A CN202410148823A CN117986224A CN 117986224 A CN117986224 A CN 117986224A CN 202410148823 A CN202410148823 A CN 202410148823A CN 117986224 A CN117986224 A CN 117986224A
- Authority
- CN
- China
- Prior art keywords
- stage
- temperature
- dmdo
- cooling
- rate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 47
- 238000007670 refining Methods 0.000 title claims abstract description 22
- 238000001816 cooling Methods 0.000 claims abstract description 66
- 238000002425 crystallisation Methods 0.000 claims abstract description 57
- 230000008025 crystallization Effects 0.000 claims abstract description 53
- 239000013078 crystal Substances 0.000 claims abstract description 38
- 230000008018 melting Effects 0.000 claims abstract description 30
- 238000002844 melting Methods 0.000 claims abstract description 30
- 239000000463 material Substances 0.000 claims abstract description 20
- 239000012043 crude product Substances 0.000 claims abstract description 19
- 230000005587 bubbling Effects 0.000 claims abstract description 13
- FFHWGQQFANVOHV-UHFFFAOYSA-N dimethyldioxirane Chemical compound CC1(C)OO1 FFHWGQQFANVOHV-UHFFFAOYSA-N 0.000 claims abstract 13
- 230000035900 sweating Effects 0.000 claims description 53
- 238000010438 heat treatment Methods 0.000 claims description 36
- 238000007599 discharging Methods 0.000 claims description 26
- 239000002994 raw material Substances 0.000 claims description 25
- 239000012452 mother liquor Substances 0.000 claims description 21
- 239000007788 liquid Substances 0.000 claims description 17
- 230000008569 process Effects 0.000 claims description 17
- 210000004243 sweat Anatomy 0.000 claims description 11
- 239000010413 mother solution Substances 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 4
- 230000003068 static effect Effects 0.000 claims description 2
- 239000000047 product Substances 0.000 abstract description 11
- 239000002904 solvent Substances 0.000 abstract description 11
- 230000006911 nucleation Effects 0.000 abstract description 5
- 238000010899 nucleation Methods 0.000 abstract description 5
- 239000000126 substance Substances 0.000 abstract description 4
- 239000012535 impurity Substances 0.000 abstract description 3
- 238000011084 recovery Methods 0.000 abstract description 2
- 238000000926 separation method Methods 0.000 abstract description 2
- 208000008454 Hyperhidrosis Diseases 0.000 description 47
- 238000000746 purification Methods 0.000 description 5
- 230000000630 rising effect Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 239000000155 melt Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- QSJXEFYPDANLFS-UHFFFAOYSA-N Diacetyl Chemical compound CC(=O)C(C)=O QSJXEFYPDANLFS-UHFFFAOYSA-N 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- CYWTZUGZRSAQEN-UHFFFAOYSA-N 4,5-dichloro-4,5-dimethyl-1,3-dioxolan-2-one Chemical compound CC1(Cl)OC(=O)OC1(C)Cl CYWTZUGZRSAQEN-UHFFFAOYSA-N 0.000 description 1
- QYIOFABFKUOIBV-UHFFFAOYSA-N 4,5-dimethyl-1,3-dioxol-2-one Chemical compound CC=1OC(=O)OC=1C QYIOFABFKUOIBV-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000006298 dechlorination reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000000857 drug effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- -1 ester compounds Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical group [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Chemical group 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- UCPYLLCMEDAXFR-UHFFFAOYSA-N triphosgene Chemical compound ClC(Cl)(Cl)OC(=O)OC(Cl)(Cl)Cl UCPYLLCMEDAXFR-UHFFFAOYSA-N 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention belongs to the technical field of chemical separation, and discloses a refining method of high-purity DMDO, which comprises the following steps: and carrying out first-stage layered melt crystallization on the DMDO coarse material with the mass content of more than or equal to 80% in a mode of bubbling in a cooling stage to assist in nucleation, so as to obtain a DMDO coarse material with the mass content of more than or equal to 95%, and carrying out second-stage layered melt crystallization on the DMDO coarse material with the mass content of more than or equal to 99.95% in a mode of bubbling in a cooling stage to assist in nucleation. The method is suitable for DMDO crude products with the content of more than or equal to 80 percent, creatively promotes the nucleation of the DMDO by bubbling in a two-stage layered melting crystallization cooling stage, reduces the operation time, reduces the purity caused by embedding impurities into a crystal layer, and has higher yield; the operation is simple, no solvent is added, the pollution of the solvent to the product is avoided, and the method is environment-friendly; the solvent recovery process is reduced, and the cost is reduced.
Description
Technical Field
The invention belongs to the technical field of chemical separation, and particularly relates to a refining method of high-purity DMDO.
Background
4, 5-Dimethyl-1, 3-dioxole-2-one, DMDO for short, is an important organic synthesis intermediate, can form ester compounds by combining with substances containing multiple groups such as carboxyl, amino, phosphate and the like, has the advantages of improving the drug effect, reducing the side effects of the drug and the like, and is widely applied to the pharmaceutical industry. The appearance of the product is white crystal, and the color gradually deepens along with the reduction of the purity.
Patent CN113149953a discloses a method for preparing DMDO, and the purification step is characterized in that the reaction solution obtained by catalysis is distilled under reduced pressure to remove the solvent, and further recrystallized to obtain high-purity DMDO. Patent CN111018824a discloses a method for synthesizing DMDO, which uses 2,3 butanedione and triphosgene to cyclize to obtain 4, 5-dichloro-4, 5-dimethyl-1, 3-dioxolan-2-one, and obtaining DMDO through dechlorination. Patent CN103483308a discloses a method for preparing DMDO using carbon dioxide, which is a purification method in which a crystallization solvent recovered by distillation is added to DMDO for recrystallization.
The above patent mainly relates to purification means such as solution crystallization, distillation, extraction concentration and the like. The solution crystallization process has the problems of difficult preparation of high-purity products, high solvent recycling cost and the like. The distillation process requires heating the water to steam, which requires a large amount of heat energy, increasing the cost of operation. In the extraction and concentration process, a large amount of solvents, heat treatment and other means are needed, and excessive energy is consumed, so that the running cost is increased. At present, a safe, efficient and energy-saving purification means is not considered to purify the high-purity (more than or equal to 99.9%) DMDO product. In contrast, the melt crystallization has the advantages of simple operation, environmental protection, no additional solvent and low energy consumption; and the melt crystallization process has unique advantages for separating isomer, thermosensitive substances and other systems. While DMDO of different compositions has a relatively mild melting point. Therefore, the development of the application of the melt crystallization to the high-purity purification of DMDO has practical application value.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a refining method of high-purity DMDO, which can obtain the high-purity DMDO with purity more than or equal to 99.95 percent and has higher yield through a two-stage layered melting crystallization mode of bubbling in a cooling stage.
The invention is realized by adopting the following technical proposal
A method for refining high purity DMDO, said method comprising the steps of:
1) Primary feeding: adding molten DMDO coarse material with mass content more than or equal to 80% into a primary layer type melt crystallizer;
2) Cooling and crystallizing: cooling the molten DMDO coarse material at a cooling rate of 1-10K/h, and bubbling at a cooling rate of 1-20 mL/min until crystals appear; the final temperature is 50-65 ℃, the temperature is kept for 0.5-1 h, and the first-stage mother liquor which is not crystallized is treated;
3) First-stage sweating: after the primary mother solution is discharged, primary sweating is carried out on the crystal layer, the heating rate is 1-15K/h, the temperature is raised to 76-78.5 ℃, the temperature is kept for 0.5-1 h, and the primary sweating is discharged;
4) Melting: heating to melt the crystal layer to obtain a molten DMDO crude product with the mass content of more than or equal to 95%, wherein the crude product enters the step 5) to be used as a raw material of secondary layer type melt crystallization;
5) Secondary feeding: adding the molten DMDO crude product with the mass content of more than or equal to 95% in the step 4) into a secondary layer type melting crystallizer;
6) Cooling and crystallizing: cooling the molten DMDO crude product at a cooling rate of 1-10K/h, and bubbling at a rate of 1-20 mL/min in the cooling process until crystals appear; the final temperature of the cooling is 55-70 ℃, the temperature is kept for 0.5-1 h, and the second-stage mother liquor is discharged;
7) Second-stage sweating: after the second-stage mother solution is discharged, performing second-stage sweating on the crystal layer, wherein the heating rate is 1-15K/h, heating to 78-80 ℃, and keeping the temperature for 0.5-1 h, and discharging second-stage sweat;
8) Melting: and after the second-stage sweat is discharged, heating to 82 ℃ until the crystal layer is completely melted and discharged, and finally obtaining the high-purity DMDO with the purity of more than 99.95%.
Further, the speed of bubbling is 1-12 mL/min.
Further, the mass percentage of the molten DMDO coarse material in the step 1) is more than or equal to 95%.
Further, the cooling rate of the step 2) is 1-8K/h, the cooling final temperature is 52-62.5 ℃, and the constant temperature is 0.5-0.8 h.
Further, the temperature rising rate of the step 3) is 1-12K/h, the final temperature of the temperature rising is 76.5-78.5 ℃, and the constant temperature is 0.5-0.8 h.
Further, the mass percentage of the crude product of the molten DMDO in the step 5) is more than or equal to 98 percent.
Further, the cooling rate of the step 6) is 1-8K/h, the final cooling temperature is 58-70 ℃, and the constant temperature is 0.5-0.8 h.
Further, the temperature rising rate of the step 7) is 1-10K/h, the final temperature rising is 79-80 ℃, and the constant temperature is 0.5-0.8 h.
Further, the step 6) returns the second-stage mother liquor which is not crystallized after the temperature is reduced to the step 1) to be used as a raw material for application.
Further, step 7) the second-stage sweat which is not crystallized when the temperature of the crystals in the second-stage melt crystallizer is raised to the final temperature is returned to step 5) to be used as a raw material.
Further, the layer-type melt crystallization adopts a static layer-type melt crystallization method or a dynamic layer-type melt crystallization method.
The invention has the advantages and positive effects that:
The invention adopts a two-stage layered melting crystallization process, is suitable for DMDO crude products with the feed content of more than or equal to 80 percent, and preferably has the mass content of more than or equal to 95 percent of the primary layered melting crystallization. The mass percentage of the secondary layer type melting crystallization is more than or equal to 98 percent, and bubbles are blown into the two-stage layer type melting crystallization in the cooling stage to promote the nucleation of DMDO, reduce the operation time, reduce the purity caused by the embedding of impurities into a crystal layer and simultaneously have higher yield; the method is simple to operate, does not add solvent, avoids pollution of the solvent to products, is environment-friendly, reduces the solvent recovery process and reduces the cost.
Drawings
FIG. 1 is a process flow diagram of a method for refining high purity DMDO of the present invention.
Detailed Description
For a better understanding of the present invention, the present invention will be described in further detail below with reference to the accompanying drawings. The features in the cases can be combined with each other without conflict. The starting materials used in the examples below were all commercially available analytically pure starting materials.
Example 1
A method for refining high purity DMDO, comprising the steps of:
1) First-stage layer type melt crystallization: 295.80g of molten DMDO coarse material with the content of 95.03% is added into a first-stage layered melting crystallizer, the temperature is reduced at a temperature reduction rate of 5K/h, and bubbles are blown into the DMDO coarse material at a temperature reduction initial process at a rate of 10mL/min until crystals appear. Cooling to the final crystallization temperature of 55 ℃, keeping the temperature for 0.8h, discharging the first-stage mother liquor for further treatment, performing first-stage sweating on crystals in the first-stage type melt crystallizer, heating to the final sweating temperature of 78.5 ℃ at the heating rate of 7K/h, keeping the temperature for 0.5h, discharging the first-stage sweating liquid, and using the first-stage sweating liquid as a first-stage raw material, thereby obtaining 243.46g of a molten DMDO crude product with the purity of 98.51%.
2) Second-stage layer type melt crystallization: adding the molten DMDO crude product obtained by the first-stage layered melt crystallization into a second-stage layered melt crystallizer, cooling at a cooling rate of 4K/h, and bubbling at a cooling initial process at a rate of 12ml/min until crystals appear. Cooling to the final crystallization temperature of 60 ℃, keeping the temperature for 0.8h, and discharging second-stage mother liquor which is used as a first-stage raw material. And (3) performing second-stage sweating on crystals in the second-stage layered melting crystallizer, heating to the final sweating temperature of 80 ℃ at a heating rate of 6K/h, keeping the temperature for 0.5h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 111.85g of high-purity DMDO product with the purity of 99.98%. The total yield was 81.46%.
Comparative example 1
A method for refining high purity DMDO, comprising the steps of:
1) First-stage layer type melt crystallization: adding 295.80g of molten DMDO coarse material with the content of 95.03% into a first-stage layered melting crystallizer, cooling at a cooling rate of 5K/h, keeping the temperature for 0.8h after cooling to a crystallization final temperature of 55 ℃, discharging a first-stage mother liquor, performing first-stage sweating on crystals in the first-stage layered melting crystallizer, heating to a sweating final temperature of 78.5 ℃ at a heating rate of 7K/h, keeping the temperature for 0.5h, discharging the first-stage sweat, and applying the first-stage sweat as a first-stage raw material to obtain 207.77g of molten DMDO coarse material with the purity of 97.95%.
2) Second-stage layer type melt crystallization: adding the molten DMDO crude product obtained by the first-stage layered melt crystallization into a second-stage layered melt crystallizer, cooling at a cooling rate of 4K/h, cooling to a crystallization final temperature of 60 ℃, and discharging second-stage mother liquor after keeping the temperature for 0.8h, wherein the second-stage mother liquor is used as a first-stage raw material. And (3) performing second-stage sweating on crystals in the second-stage layered melting crystallizer, heating to the final sweating temperature of 80 ℃ at the heating rate of 6K/h, keeping the temperature for 0.5h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 88.68g of DMDO product. The purity was 99.32%. The yield thereof was found to be 70.73%.
Example 2
A method for refining high purity DMDO, comprising the steps of:
1) First-stage layer type melt crystallization: 299.19g of molten DMDO coarse material with the content of 90.4% is added into a first-stage layered melting crystallizer, the temperature is reduced at the cooling rate of 8K/h, and bubbles are blown in at the cooling initial process at the rate of 8mL/min until crystals appear. Cooling to the final crystallization temperature of 60 ℃, keeping the temperature for 0.7h, discharging a first-stage mother liquor, performing first-stage sweating on crystals in the first-stage type melt crystallizer, heating to the final sweating temperature of 77.5 ℃ at the heating rate of 12K/h, keeping the temperature for 0.6h, discharging the first-stage sweating liquid, and using the first-stage sweating liquid as a first-stage raw material, thereby obtaining 221.86g of DMDO crude product with the purity of 98.37%.
2) Second-stage layer type melt crystallization: adding the molten DMDO crude product obtained by the first-stage layered melt crystallization into a second-stage layered melt crystallizer, cooling at a cooling rate of 6K/h, and bubbling at a cooling initial process at a rate of 8ml/min until crystals appear. Cooling to the final crystallization temperature of 65 ℃, keeping the temperature for 0.7h, and discharging second-stage mother liquor which is used as a first-stage raw material. And (3) performing second-stage sweating on crystals in the second-stage layered melt crystallizer, heating to the final sweating temperature of 79.9 ℃ at the heating rate of 10K/h, and keeping the temperature for 0.6h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 99.26g of high-purity DMDO product. The purity was 99.96% and the total yield was 73.56%.
Comparative example 2
A method for refining high purity DMDO, comprising the steps of:
1) First-stage layer type melt crystallization: adding 299.19g of molten DMDO coarse material with the content of 90.4% into a first-stage layered melting crystallizer, cooling at a cooling rate of 8K/h, keeping the temperature for 0.7h after cooling to a crystallization final temperature of 60 ℃, discharging a first-stage mother liquor, performing first-stage sweating on crystals in the first-stage layered melting crystallizer, heating to a sweating final temperature of 77.5 ℃ at a heating rate of 12K/h, keeping the temperature for 0.6h, discharging the first-stage sweat, and applying the first-stage sweat as a first-stage raw material to obtain 190.10g of molten DMDO coarse material with the purity of 97.56%.
2) Second-stage layer type melt crystallization: adding the molten DMDO crude product obtained by the first-stage layered melt crystallization into a second-stage layered melt crystallizer, cooling at a cooling rate of 6K/h, cooling to a final crystallization temperature of 65 ℃, and discharging second-stage mother liquor after keeping the temperature for 0.7h, wherein the second-stage mother liquor is used as a first-stage raw material. And (3) performing second-stage sweating on crystals in the second-stage layered melting crystallizer, heating to the final sweating temperature of 79.9 ℃ at the heating rate of 10K/h, and keeping the temperature for 0.6h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 73.13g of DMDO product. The purity is 99.07%. The total yield was 64.56%.
Example 3
A coupling refining method of high-purity DMDO comprises the following steps:
1) First-stage layer type melt crystallization: 306.70g of molten DMDO coarse material with the content of 80.5% is added into a first-stage layered melting crystallizer, the temperature is reduced at the cooling rate of 3K/h, and bubbles are blown into the molten DMDO coarse material at the cooling initial process at the rate of 10ml/min until crystals appear. Cooling to the final crystallization temperature of 62.5 ℃, keeping the temperature for 0.5h, discharging a first-stage mother solution, sweating crystals in the first-stage type melt crystallizer, heating to the final sweating temperature of 76.5 ℃ at the heating rate of 4K/h, keeping the temperature for 0.8h, discharging first-stage sweat, and applying the first-stage sweat as a first-stage raw material to obtain 175.21g of a molten DMDO crude product with the purity of 98.28%.
2) Second-stage layer type melt crystallization: adding the molten DMDO obtained by the first-stage layer-type melt crystallization into a second-stage layer-type melt crystallizer, cooling at a cooling rate of 2K/h, and bubbling at a cooling initial process at a rate of 10ml/min until crystals appear. Cooling to the final crystallization temperature of 68.5 ℃, keeping the temperature for 0.5h, and discharging second-stage mother liquor which is used as a first-stage raw material. And (3) performing second-stage sweating on crystals in the second-stage layered melt crystallizer, heating to the final sweating temperature of 79.5 ℃ at the heating rate of 3K/h, and keeping the temperature for 0.8h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 93.29g of high-purity DMDO product. The purity was 99.95%. The total yield was 57.07%.
Comparative example 3
A method for refining high purity DMDO, comprising the steps of:
1) First-stage layer type melt crystallization: 306.70g of molten DMDO coarse material with the content of 80.5% is added into a first-stage layered melting crystallizer, and the temperature is reduced at a cooling rate of 3K/h to 62.5 ℃ of final crystallization temperature. Discharging a first-stage mother liquor after keeping the temperature for 0.5h, performing first-stage sweating on crystals in the first-stage layered melting crystallizer, heating to the final sweating temperature of 76.5 ℃ at the heating rate of 4K/h, keeping the temperature for 0.8h, discharging the first-stage sweating, and using the first-stage sweating as a first-stage raw material to obtain 164.06g of a molten DMDO crude product with the purity of 97.22%.
2) Second-stage layer type melt crystallization: adding the molten DMDO obtained by the first-stage layer-type melt crystallization into a second-stage layer-type melt crystallizer, cooling at a cooling rate of 2K/h, and cooling to a final crystallization temperature of 68.5 ℃. And discharging the second-stage mother liquor after the constant temperature is maintained for 0.5h, wherein the second-stage mother liquor is used as a first-stage raw material for application. And (3) performing second-stage sweating on crystals in the second-stage layered melting crystallizer, heating to the final sweating temperature of 79.5 ℃ at the heating rate of 3K/h, and keeping the temperature for 0.8h, discharging second-stage sweating liquid, and applying the second-stage sweating liquid as a second-stage raw material to obtain 68.64g of DMDO product. The purity was 98.34% and the total yield was 54.51%.
By comparing the two-stage laminar melting crystallization process with the bubble-blown two-stage laminar melting crystallization process, the laminar melting crystallization without the bubble-blown can not reach the target purity under the two-stage crystallization condition, and if the target purity is reached, a higher operation level is required, which clearly increases the operation cost. And bubbles are blown in under the condition of secondary layer type melting crystallization, heterogeneous nucleation sites are provided, impurities are reduced to be embedded into the crystal layer, growth of the crystal layer is facilitated, and crystal purity is improved. Meanwhile, the process time is shortened, and the operation cost is reduced.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that variations and modifications can be made without departing from the scope of the invention.
Claims (9)
1. A method for refining high purity DMDO, comprising the steps of:
step 1) primary feeding: adding molten DMDO coarse material with mass content more than or equal to 80% into a primary layer type melt crystallizer;
Step 2) cooling and crystallizing: cooling the molten DMDO coarse material at a cooling rate of 1-10K/h, and bubbling air bubbles at a cooling process at a cooling rate of 1-20 mL/min until crystals appear; the final temperature is 50-65 ℃, the temperature is kept for 0.5-1 h, and the first-stage mother liquor which is not crystallized is treated;
Step 3) first-stage sweating: after the first-stage mother liquor is discharged, performing first-stage sweating on the crystal layer, wherein the heating rate is 1-15K/h, heating to 76-78.5 ℃, and keeping the temperature for 0.5-1 h, and discharging the first-stage sweating liquid which is used as the raw material of the step 1);
Step 4) material melting: heating to melt the crystal layer to obtain a molten DMDO crude product with the mass content of more than or equal to 95%, wherein the crude product enters the step 5) to be used as a raw material of secondary layer type melt crystallization;
Step 5) secondary feed: adding the molten DMDO crude product with the mass content of more than or equal to 95% in the step 4) into a secondary layer type melting crystallizer;
And 6) cooling and crystallizing: cooling the molten DMDO crude product at a cooling rate of 1-10K/h, and bubbling at a rate of 1-20 mL/min in the cooling process until crystals appear; the final temperature is reduced to 55-70 ℃, the temperature is kept for 0.5-1 h, and the second-stage mother liquor is discharged;
step 7) second-stage sweating: after the second-stage mother solution is discharged, second-stage sweating is carried out on the crystal layer, the heating rate is 1-15K/h, the temperature is raised to 78-80 ℃, the temperature is kept for 0.5-1 h, and the second-stage sweating is discharged;
step 8) material melting: and after the second-stage sweat is discharged, heating until the crystal layer is completely melted and discharged, and finally obtaining the high-purity DMDO with the purity of more than 99.95%.
2. The refining method according to claim 1, wherein the bubbling rate is 1 to 12mL/min.
3. The refining method according to claim 1, wherein the cooling rate of step 2) is 1-8K/h, the final cooling temperature is 52-62.5 ℃, and the constant temperature is 0.5-0.8 h.
4. The refining method according to claim 1, wherein the rate of temperature rise in step 3) is 1-12K/h, the final temperature of temperature rise is 76.5-78.5 ℃, and the temperature is kept constant for 0.5-0.8 h.
5. The refining method according to claim 1, wherein the cooling rate of step 6) is 1-8K/h, the final cooling temperature is 58-70 ℃, and the constant temperature is 0.5-0.8 h.
6. The refining method as claimed in claim 1, wherein the rate of temperature rise in the step 7) is1 to 10K/h, the final temperature of temperature rise is 79 to 80 ℃, and the temperature is kept for 0.5 to 0.8h.
7. The refining method according to claim 1, wherein the step 6) returns the second-stage mother liquor which is not crystallized after the temperature reduction to the step 1) as a raw material for reuse.
8. The refining method as recited in claim 1, wherein in the step 7), the second-stage sweat which is not crystallized when the temperature of the crystals in the second-stage melt crystallizer is raised to the final temperature is returned to the step 5) to be used as a raw material.
9. The refining method according to claim 1, wherein the layer-type melt crystallization is a static layer-type melt crystallization method or a dynamic layer-type melt crystallization method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410148823.2A CN117986224A (en) | 2024-02-02 | 2024-02-02 | Refining method of high-purity DMDO (digital media do) |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410148823.2A CN117986224A (en) | 2024-02-02 | 2024-02-02 | Refining method of high-purity DMDO (digital media do) |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117986224A true CN117986224A (en) | 2024-05-07 |
Family
ID=90895780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410148823.2A Pending CN117986224A (en) | 2024-02-02 | 2024-02-02 | Refining method of high-purity DMDO (digital media do) |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117986224A (en) |
-
2024
- 2024-02-02 CN CN202410148823.2A patent/CN117986224A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6579957B2 (en) | Purification method of natural vanillin | |
| CN1229314C (en) | Obtaining anthracene and carbazole by melt-crystallization | |
| KR101926436B1 (en) | Process for purifying a crude composition of dialkyl ester of 2,5-furandicarboxylic acid | |
| US9096516B2 (en) | Production method of N-vinyl-2-pyrrolidone | |
| CN103342671B (en) | A kind of method utilizing acetylizad saponification liquor to prepare L-Methionine | |
| US4780568A (en) | Purification of methacrylic acid from an oxydehydrogenation by crystallization | |
| CN117986224A (en) | Refining method of high-purity DMDO (digital media do) | |
| CN109970624B (en) | Method for purifying haloperidol | |
| JPH02212450A (en) | Method for continuous purification of bisphenol | |
| CN113651699B (en) | Method for preparing high-purity 2, 4-dinitrochlorobenzene by layered melt crystallization | |
| CN1273421C (en) | Method for preparing high-purity biphenyl from crude biphenyl | |
| EP0757030B1 (en) | Process for purifying diaryl carbonates | |
| CN112661727B (en) | Purification method of 7- (2, 2-trichloroethyl oxycarbonyl) taxol | |
| CN114478235B (en) | Method for purifying organic acid in fermentation liquor | |
| JP2623344B2 (en) | Method for separation and purification of β-monoisopropylnaphthalene | |
| CN109734578B (en) | Purification method of adipic acid by-product mixed dibasic acid, product and application | |
| CN112694397B (en) | Method for purifying 2, 6-naphthalenedicarboxylic acid | |
| CN112724012B (en) | Method for refining long-chain dibasic acid | |
| US3016401A (en) | Naphthalene separation process | |
| CN117447350A (en) | Comprehensive recycling method for atorvastatin M4 organic waste | |
| CN113717043A (en) | Method for efficiently recovering low-content benzoic acid by melt crystallization | |
| CN114507112A (en) | Preparation method of high-purity durene | |
| CN117361587A (en) | Method for recovering lithium chloride from lithium-containing waste acid water of chiral lactone | |
| JP2003012593A (en) | Improved method for purifying and pharmaceutically preparing ortho-phthalaldehyde | |
| CN114763333A (en) | Separation and recovery method of peroxide TBHP and byproduct TBA in styrene oxide mother liquor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination |