CN112979421A - Synthesis process of condensation by-product - Google Patents
Synthesis process of condensation by-product Download PDFInfo
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- CN112979421A CN112979421A CN202110285914.7A CN202110285914A CN112979421A CN 112979421 A CN112979421 A CN 112979421A CN 202110285914 A CN202110285914 A CN 202110285914A CN 112979421 A CN112979421 A CN 112979421A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/36—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal
- C07C29/38—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal by reaction with aldehydes or ketones
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
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- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention discloses a synthesis process of a condensation byproduct, which comprises the following process steps: condensation reaction: under the action of an alkaline catalyst, carrying out condensation reaction on formaldehyde and a chemical A to obtain a condensation reaction liquid containing a chemical B and formate; wherein, the chemical A is n-butyraldehyde or isobutyraldehyde; chemical B corresponds to trimethylolpropane or neopentyl glycol; evaporation and dehydration: evaporating and dehydrating the condensation reaction liquid to prepare an evaporated liquid; centrifuging: centrifuging the evaporated liquid, and separating out part of formate in the evaporated liquid; and (3) rectification: performing component segmentation on the centrifuged mother liquor by adopting a rectification method to obtain a segmentation component containing a chemical B, wherein the chemical B is the obtained condensation byproduct; wherein, a protective agent is added in the rectification process to avoid the degradation of the chemical B in a temperature environment; the protective agent is metal organic salt; the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is not lower than 180 ℃. It adopts solvent-free method, can raise the yield of condensation by-product, and its colour number is less than or equal to 10, and meets the requirements of product.
Description
Technical Field
The invention relates to a synthesis process of a condensation byproduct.
Background
At present, the preparation process of trimethylolpropane or neopentyl glycol adopts a solvent method, and specifically comprises the following steps: 1. under the action of an alkaline catalyst, carrying out condensation reaction on formaldehyde and n-butyl aldehyde or iso-butyl aldehyde to obtain a condensation reaction liquid containing trimethylolpropane or neopentyl glycol and formate; 2. evaporating and dehydrating the condensation reaction liquid to obtain an evaporated liquid; 3, extracting the evaporated liquid by a solvent to obtain an oil phase and a water phase, wherein the oil phase contains trimethylolpropane or neopentyl glycol and the solvent, the water phase contains excessive formaldehyde, water and formate, rectifying and desolventizing the oil phase to obtain the trimethylolpropane or neopentyl glycol, and the preparation process of the trimethylolpropane specifically refers to the Chinese patent with the publication number of CN 1911886A. in the step, because the formate reacts with the trimethylolpropane or neopentyl glycol at a high temperature to cause great degradation of the trimethylolpropane or neopentyl glycol, the formate needs to be separated from the trimethylolpropane or neopentyl glycol to collect the trimethylolpropane or neopentyl glycol, but the problem of great degradation of the trimethylolpropane or neopentyl glycol needs to be avoided, but the process steps are relatively complicated, the yield is less than or equal to 80%, the color number (APHA) is more than or equal to 10, and the solvent needs to be used in a great amount, causes the phenomena of excessive solvent consumption, high energy consumption and easy pollution in the process.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects of the prior art and provide a synthesis process of a condensation byproduct, which adopts a solvent-free method, can improve the yield of the condensation byproduct, has a color number less than or equal to 10 and meets the product requirements.
The technical scheme adopted by the invention for solving the technical problems is as follows: a synthesis process of condensation byproducts comprises the following process steps:
condensation reaction: under the action of an alkaline catalyst, carrying out condensation reaction on formaldehyde and a chemical A to obtain a condensation reaction liquid containing a chemical B and formate; wherein, the chemical A is n-butyraldehyde or isobutyraldehyde; chemical B corresponds to trimethylolpropane or neopentyl glycol;
evaporation and dehydration: evaporating and dehydrating the condensation reaction liquid to prepare an evaporated liquid;
centrifuging: centrifuging the evaporated liquid, and separating out part of formate in the evaporated liquid;
and (3) rectification: performing component segmentation on the centrifuged mother liquor by adopting a rectification method to obtain a segmentation component containing a chemical B, wherein the chemical B is the obtained condensation byproduct; wherein the content of the first and second substances,
adding a protective agent in the rectification process to prevent the chemical B from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is not lower than 180 ℃.
Further, a protective agent is added in the evaporation dehydration process to prevent the chemical B from degrading in a temperature environment.
Further, the metal organic salt is an aliphatic or aromatic organic salt of a metal.
Further, the aliphatic organic salt is an aliphatic organic salt containing 4 to 20 carbon atoms per molecule.
Further, the aromatic organic salt is an aromatic organic salt containing 7 to 15 carbon atoms per molecule.
Further, the metal in the metal organic salt is one of zinc, tin, copper, tungsten, chromium and silver.
Further, the synthesis process of the condensation byproduct further comprises the steps of:
the split component containing chemical B is re-rectified at least once: and rectifying the split component containing the chemical B at least once again by a rectification method of a rectification step.
Further, when the chemical A is n-butyraldehyde and the chemical B is trimethylolpropane, the corresponding rectification temperature is 180-300 ℃.
Further, when the chemical A is isobutyraldehyde and the chemical B is neopentyl glycol, the corresponding rectification temperature is 200-350 ℃.
Further, the temperature of evaporation dehydration is 100-140 ℃.
After the technical scheme is adopted, the protective agent metal organic salt is added in the rectification step, the metal organic salt can block active products such as trimethylolpropane and neopentyl glycol in a condensation reaction liquid from generating chain reaction in a temperature environment, and the trimethylolpropane and the neopentyl glycol are prevented from being greatly degraded in the temperature environment, so that the final yield of condensation byproducts such as trimethylolpropane or neopentyl glycol is finally improved, and the degradation of the active products is avoided, so that the color number of the final product is ensured to be less than or equal to 10. The rectification temperature in the invention is mainly controlled to ensure that light components, medium components and heavy components can be well separated.
Detailed Description
The invention provides a synthesis process of a condensation byproduct, and a person skilled in the art can use the content for reference and appropriately improve the process parameters to realize the synthesis process. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the scope of the invention. While the methods and applications of this invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and modifications in the methods and applications described herein, as well as other suitable variations and combinations, may be made to implement and use the techniques of this invention without departing from the spirit and scope of the invention.
A synthesis process of condensation byproducts comprises the following process steps:
condensation reaction: under the action of an alkaline catalyst, carrying out condensation reaction on formaldehyde and a chemical A to obtain a condensation reaction liquid containing a chemical B and formate; wherein, the chemical A is n-butyraldehyde or isobutyraldehyde; chemical B corresponds to trimethylolpropane or neopentyl glycol;
evaporation and dehydration: evaporating and dehydrating the condensation reaction liquid to prepare an evaporated liquid;
centrifuging: centrifuging the evaporated liquid, and separating out part of formate in the evaporated liquid;
and (3) rectification: performing component segmentation on the centrifuged mother liquor by adopting a rectification method to obtain a segmentation component containing a chemical B, wherein the chemical B is the obtained condensation byproduct; wherein the content of the first and second substances,
adding a protective agent in the rectification process to prevent the chemical B from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is not lower than 180 ℃.
Specifically, the condensation reaction is carried out by adopting a reaction kettle, the temperature is controlled to be less than or equal to 70 ℃, and the reaction time is half an hour to 3 hours.
The basic catalyst may be calcium hydroxide.
Further, a protective agent is added in the evaporation dehydration process to prevent the chemical B from degrading in a temperature environment.
Further, the metal organic salt is an aliphatic or aromatic organic salt of a metal.
Further, the aliphatic organic salt is an aliphatic organic salt containing 4 to 20 carbon atoms per molecule.
Further, the aromatic organic salt is an aromatic organic salt containing 7 to 15 carbon atoms per molecule.
Further, the metal in the metal organic salt is one of zinc, tin, copper, tungsten, chromium and silver.
Further, the synthesis process of the condensation byproduct further comprises the steps of:
the split component containing chemical B is re-rectified at least once: and rectifying the split component containing the chemical B at least once again by a rectification method of a rectification step.
Further, when the chemical A is n-butyraldehyde and the chemical B is trimethylolpropane, the corresponding rectification temperature is 180-300 ℃.
Further, when the chemical A is isobutyraldehyde and the chemical B is neopentyl glycol, the corresponding rectification temperature is 200-350 ℃.
Further, the temperature of evaporation dehydration is 100-140 ℃.
In order that the present invention may be more clearly understood, the following detailed description of the present invention is given with reference to specific examples.
Example one
S1, adding 2.2 tons of formaldehyde with the content of 37%, 0.5 ton of calcium hydroxide with the content of 95% and 600 kilograms of n-butyl aldehyde with the content of 99.5% into a reaction kettle with a stirrer for condensation reaction to obtain a condensation reaction liquid containing trimethylolpropane and calcium formate; wherein the reaction temperature is 60 ℃, and the reaction time is 30 minutes;
s2, evaporating and dehydrating the condensation reaction liquid through an evaporation kettle, adding a protective agent into the evaporation kettle to prevent trimethylolpropane from degrading to prepare an evaporation liquid, wherein the temperature of evaporation and dehydration is 110 ℃, the dehydration rate is controlled to be 45%, and part of calcium formate precipitated at the bottom of the evaporation liquid is centrifugally separated to obtain 0.63 ton of 99.6% calcium formate;
s3: the mother liquor after centrifugation is subjected to component division in a rectifying tower in a heating and rectifying mode to obtain 1.0 ton of a division component containing 99.5 percent of trimethylolpropane, wherein the trimethylolpropane is the obtained condensation byproduct; wherein the content of the first and second substances,
adding a protective agent in the rectification step to prevent trimethylolpropane from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is 190 ℃.
In this embodiment, the protective agent added in the evaporation dehydration step is stannous octoate; the protective agent added in the rectification step is tin octoate.
In this example, the color number measured by the APHA chroma test method is 7, which meets the requirement.
Example two
S1, adding 2.2 tons of formaldehyde with the content of 37%, 0.5 ton of calcium hydroxide with the content of 95% and 600 kilograms of n-butyl aldehyde with the content of 99.5% into a reaction kettle with a stirrer for condensation reaction to obtain a condensation reaction liquid containing trimethylolpropane and calcium formate; wherein the reaction temperature is 55 ℃, and the reaction time is 1 hour;
s2, evaporating and dehydrating the condensation reaction liquid through an evaporation kettle, adding a protective agent into the evaporation kettle to prevent trimethylolpropane from degrading to prepare an evaporation liquid, wherein the temperature of evaporation and dehydration is 130 ℃, the dehydration rate is controlled to be 60%, and part of calcium formate precipitated at the bottom of the evaporation liquid is centrifugally separated to obtain 0.60 ton of 99.6% calcium formate;
s3: the mother liquor after centrifugation is subjected to component division in a rectifying tower in a heating and rectifying mode to obtain 1.0 ton of a division component containing 99.5 percent of trimethylolpropane, wherein the trimethylolpropane is the obtained condensation byproduct; wherein the content of the first and second substances,
adding a protective agent in the rectification step to prevent trimethylolpropane from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is 190 ℃.
In this embodiment, the protective agent added in the evaporation dehydration step is stannous nonanoate; the protective agent added in the rectification step is tin nonanoate.
In this example, the color number measured by APHA chroma test method is 8, which meets the requirement.
EXAMPLE III
S1, adding 1.65 tons of formaldehyde with the content of 37%, 0.55 tons of calcium hydroxide with the content of 98% and 0.733 tons of isobutyraldehyde with the content of 99.5% into a reaction kettle with a stirrer for condensation reaction to obtain a condensation reaction liquid containing neopentyl glycol and calcium formate; wherein the reaction temperature is 50 ℃, and the reaction time is 1 hour;
s2, evaporating and dehydrating the condensation reaction liquid through an evaporation kettle, adding a protective agent into the evaporation kettle to prevent neopentyl glycol from degrading to obtain an evaporation liquid, controlling the temperature of evaporation and dehydration to be 130 ℃ and the dehydration rate to be 80%, and centrifugally separating part of calcium formate precipitated at the bottom of the evaporation liquid to obtain 98% calcium formate of 0.65 ton content;
s3: the centrifuged mother liquor is subjected to component division in a rectifying tower in a heating and rectifying mode to obtain a division component containing neopentyl glycol with the content of 99.5 percent, wherein the neopentyl glycol is an obtained condensation byproduct, the amount of the neopentyl glycol is 1.0 ton, and the content of the neopentyl glycol is 99.5 percent; wherein the content of the first and second substances,
a protective agent is added in the rectification step to prevent neopentyl glycol from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment was absolute pressure and the temperature was 290 ℃.
In this embodiment, the protective agent added in the evaporation dehydration step is stannous decanoate; the protective agent added in the rectification step is tin decanoate.
In this example, the color number measured by APHA chroma test method is 9, which meets the requirement.
Example four
S1, adding 1.65 tons of formaldehyde with the content of 37%, 0.55 tons of calcium hydroxide with the content of 98% and 0.733 tons of isobutyraldehyde with the content of 99.5% into a reaction kettle with a stirrer for condensation reaction to obtain a condensation reaction liquid containing neopentyl glycol and calcium formate; wherein the reaction temperature is 60 ℃, and the reaction time is 45 minutes;
s2, evaporating and dehydrating the condensation reaction liquid through an evaporation kettle, adding a protective agent into the evaporation kettle to prevent neopentyl glycol from degrading to obtain an evaporation liquid, controlling the temperature of evaporation and dehydration to be 140 ℃ and the dehydration rate to be 80%, and centrifugally separating part of calcium formate precipitated at the bottom of the evaporation liquid to obtain 0.64 ton of 98% calcium formate;
s3: carrying out component segmentation on the centrifuged mother liquor in a rectifying tower in a heating and rectifying mode to obtain a segmentation component containing neopentyl glycol with the content of 99.5%, wherein the neopentyl glycol is an obtained condensation byproduct, the amount of the neopentyl glycol is 1.0 ton, and the content of the neopentyl glycol is 99.6%; wherein the content of the first and second substances,
a protective agent is added in the rectification step to prevent neopentyl glycol from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment was absolute pressure and the temperature was 290 ℃.
In this embodiment, the protective agent added in the evaporation dehydration step is stannous octoate; the protective agent added in the rectification step is tin octoate.
In this example, the color number measured by APHA chroma test method is 8, which meets the requirement.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A process for the synthesis of a condensation by-product, comprising the steps of:
condensation reaction: under the action of an alkaline catalyst, carrying out condensation reaction on formaldehyde and a chemical A to obtain a condensation reaction liquid containing a chemical B and formate; wherein, the chemical A is n-butyraldehyde or isobutyraldehyde; chemical B corresponds to trimethylolpropane or neopentyl glycol;
evaporation and dehydration: evaporating and dehydrating the condensation reaction liquid to prepare an evaporated liquid;
centrifuging: centrifuging the evaporated liquid, and separating out part of formate in the evaporated liquid;
and (3) rectification: performing component segmentation on the centrifuged mother liquor by adopting a rectification method to obtain a segmentation component containing a chemical B, wherein the chemical B is the obtained condensation byproduct; wherein the content of the first and second substances,
adding a protective agent in the rectification process to prevent the chemical B from degrading in a temperature environment; the protective agent is metal organic salt;
the rectification conditions are as follows: the vacuum environment is absolutely pressed, and the temperature is not lower than 180 ℃.
2. The process for synthesizing a condensation by-product according to claim 1,
and adding a protective agent in the evaporation dehydration process to prevent the chemical B from degrading in a temperature environment.
3. The process for synthesizing a condensation by-product according to claim 1,
the metal organic salt is aliphatic or aromatic organic salt of metal.
4. The process for synthesizing a condensation by-product according to claim 3,
the aliphatic organic salt is an aliphatic organic salt containing 4-20 carbon atoms per molecule.
5. The process for synthesizing a condensation by-product according to claim 3,
the aromatic organic salt is an aromatic organic salt containing 7 to 15 carbon atoms per molecule.
6. The process for synthesizing a condensation by-product according to claim 1,
the metal in the metal organic salt is one of zinc, tin, copper, tungsten, chromium and silver.
7. The process for the synthesis of a condensation by-product according to claim 1, further comprising the steps of:
the split component containing chemical B is re-rectified at least once: and rectifying the split component containing the chemical B at least once again by a rectification method of a rectification step.
8. The process for synthesizing a condensation by-product according to claim 1,
when the chemical A is n-butyraldehyde and the chemical B is trimethylolpropane, the corresponding rectification temperature is 180-300 ℃.
9. The process for synthesizing a condensation by-product according to claim 1,
when the chemical A is isobutyraldehyde and the chemical B is neopentyl glycol, the corresponding rectification temperature is 200-350 ℃.
10. The process for synthesizing a condensation by-product according to claim 1,
the temperature of evaporation dehydration is 100-140 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202110285914.7A CN112979421A (en) | 2021-03-17 | 2021-03-17 | Synthesis process of condensation by-product |
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| CN202110285914.7A CN112979421A (en) | 2021-03-17 | 2021-03-17 | Synthesis process of condensation by-product |
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| CN202110285914.7A Withdrawn CN112979421A (en) | 2021-03-17 | 2021-03-17 | Synthesis process of condensation by-product |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115536491A (en) * | 2021-09-30 | 2022-12-30 | 湖北宜化化工科技研发有限公司 | Production method for producing trimethylolpropane by recycling carbide slag |
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2021
- 2021-03-17 CN CN202110285914.7A patent/CN112979421A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115536491A (en) * | 2021-09-30 | 2022-12-30 | 湖北宜化化工科技研发有限公司 | Production method for producing trimethylolpropane by recycling carbide slag |
| CN115536491B (en) * | 2021-09-30 | 2024-04-12 | 湖北宜化化工科技研发有限公司 | Production method for producing trimethylolpropane by recycling carbide slag |
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Application publication date: 20210618 |