CN113750437A - Method for enhancing interface activation to efficiently biodegrade PET (polyethylene terephthalate) - Google Patents
Method for enhancing interface activation to efficiently biodegrade PET (polyethylene terephthalate) Download PDFInfo
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- CN113750437A CN113750437A CN202111112786.2A CN202111112786A CN113750437A CN 113750437 A CN113750437 A CN 113750437A CN 202111112786 A CN202111112786 A CN 202111112786A CN 113750437 A CN113750437 A CN 113750437A
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
- A62D3/02—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by biological methods, i.e. processes using enzymes or microorganisms
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/20—Organic substances
- A62D2101/28—Organic substances containing oxygen, sulfur, selenium or tellurium, i.e. chalcogen
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Abstract
The invention is based on an alkali-resistant whole-cell biocatalyst, and utilizes an interfacial activator to create a chemical-biological combined catalytic system for degrading PET micro-plastics. The method comprises the following operation steps: firstly, preparing an alkaline liquid culture medium according to a formula; then, adding a Tween series interface activator, fully dispersing in an ultrasonic instrument, and carrying out interface activation for 2h on a constant-temperature shaking table; and finally, sterilizing the system, and inoculating an alkali-resistant strain to carry out biological-chemical combined degradation. The method is simple to operate, environment-friendly, non-toxic and low in cost, and can efficiently activate the degradation interface and reduce the PET surface activation energy, so that the biological-chemical combined degradation efficiency of the PET micro plastic is improved. The invention not only provides an effective solution for safely and thoroughly removing the PET micro-plastic, but also establishes demonstration and leading effects for realizing green treatment of other difficultly degraded artificial high polymer materials.
Description
Technical Field
The invention relates to a polyester degradation treatment method, in particular to a method for catalyzing efficient degradation of PET by an interfacial biological activator, and belongs to the field of polyester textile processing.
Technical Field
Biodegradation is considered to be the safest and most thorough method for solving the problems of the terylene micro plastic. However, PET is a bio-resistant high molecular compound having high crystallinity, a dense structure and a highly hydrophobic surface. In addition, as a chemically synthesized material, polyester appears for a short time as compared with a natural product, and microorganisms capable of efficiently decomposing PET have not been developed in nature.
Although, various microorganisms and enzymes for biodegradation of PET have been reported in recent years, their productivity is limited. Considering that the degradation of PET is an interfacial catalytic reaction, the use of an interfacial catalyst is considered to be an effective method for improving the degradation of PET. The interfacial catalyst, whether chemically or biologically degraded, can reduce surface tension, making enzymes and chemical molecules more likely to contact the polymer surface, and ultimately increasing the efficiency of the interfacial reaction.
The invention relates to a chemical-biological combined catalytic system for degrading PET (polyethylene terephthalate) micro-plastic by utilizing an interfacial activator based on an alkali-resistant whole-cell biocatalyst. In the process of corroding the PET surface by enzyme and alkaline molecules, the interfacial biological reaction is enhanced by applying an interfacial activator, and the biodegradation efficiency is enhanced. Because the interfacial activator used in the invention belongs to esters, the interfacial activator can also be used as a carbon source to be utilized by microorganism growth and reproduction in the PET biodegradation process. Therefore, the method can not further cause environmental pollution and meets the requirements of ecological dyeing and finishing.
Disclosure of Invention
The invention aims to solve the technical problem of providing a novel method for efficiently degrading PET by utilizing interface activation based on an alkali-resistant whole-cell biocatalyst aiming at the defect of low efficiency of the existing enzyme and microorganism degradation of PET.
The technical scheme adopted by the invention is as follows: a novel method for efficiently degrading PET by utilizing interface activation based on an alkali-resistant whole-cell biocatalyst. The method is characterized by comprising the following steps:
(1) preparation of PET micro plastic: firstly, polyester superfine fiber is refined, surface grease is removed, and the polyester superfine fiber is fully dried after being washed for multiple times; then, crushing the substrate to the size of micro plastic, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing an alkaline liquid culture medium according to a culture formula of the alkali-resistant Comamonas testosteroni, and additionally adding 0.5-3% of interfacial activator by volume. The system is placed in an ultrasonic instrument to ensure that the PET and the interfacial activator are fully and uniformly dispersed, and the PET and the interfacial activator are placed on a constant temperature shaking table at 37 ℃ and 140rpm for treatment for 2 to 5 hours to ensure that the PET surface is fully emulsified. The formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3-5 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 20-40% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, and continuously placing the alkaline liquid culture medium into a constant-temperature incubator at 37 ℃ and 140rpm for culture. This was repeated for 60 days.
Preferably, the drying method of the PET after refining in the step (1) is: and (5) freeze drying.
Preferably, the way of pulverizing PET in step (1) is: physical cutting, using an ultracentrifugal cutter.
Preferably, in the step (2), the ultrasonic temperature is 30 ℃, the ultrasonic frequency is 40KHz, and the ultrasonic time is 0.5 h; the surfactant is Tween 20, the volume is 1%, and the interfacial activation time is 2 h.
Preferably, the displacement time of the new fermentation broth in step (3) is 3 days.
Preferably, the displaced volume of fresh fermentation broth in step (4) is 30%.
Due to the adoption of the technical scheme, the method has the following beneficial effects:
(1) degradation of PET is an interfacial reaction, both chemical and biological. Therefore, the addition of the interfacial activator can enable the alkaline molecules and the extracellular enzyme to be quickly and specifically combined with the PET micro-plastic, and promote the high-efficiency degradation reaction.
(2) From the aspects of environmental protection and high-efficiency degradation, the invention utilizes the alkali-resistant testosterone comamonas as the whole-cell biocatalyst, not only can lead PET to be slightly degraded in a weak alkaline environment, but also saves the steps of enzyme extraction and purification in the PET biodegradation process.
(3) Because the added interface activator is an ester molecule, the interface activator can be assimilated and absorbed by microorganisms as a carbon source in the degradation process of PET. Therefore, the method does not cause environmental pollution, accords with the development direction of ecological dyeing and finishing, and has wide application prospect.
Detailed Description
Example 1
(1) Preparation of PET micro plastic: firstly, polyester superfine fibers and slices are refined, surface grease is removed, and the polyester superfine fibers and the slices are fully dried after being washed for multiple times; then, crushing the substrate to the size of micro plastic, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing 200ml of culture solution according to a culture formula of alkali-resistant Comamonas testosteroni in a 500ml conical flask, and adding 1% by volume of Tween 20; the system is placed in an ultrasonic instrument to ensure that the PET and the interfacial active agent are uniformly dispersed, and the system is placed on a constant temperature shaking table at 37 ℃ and 140rpm for treatment for 2 to 5 hours to ensure that the surface of the PET is fully emulsified. The formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 30% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, and continuously placing the alkaline liquid culture medium into a constant-temperature incubator at 37 ℃ and 140rpm for culture. This was repeated for 60 days.
Example 2
(1) Preparation of PET micro plastic: firstly, polyester superfine fibers and slices are refined, surface grease is removed, and the polyester superfine fibers and the slices are fully dried after being washed for multiple times; then, crushing the substrate to the size of micro plastic, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing 200ml of culture solution according to a culture formula of alkali-resistant Comamonas testosteroni in a 500ml conical flask, and adding 1% by volume of Tween 40; the system is placed in an ultrasonic instrument to ensure that the PET and the interfacial active agent are uniformly dispersed, and the system is placed on a constant temperature shaking table at 37 ℃ and 140rpm for treatment for 2 to 5 hours to ensure that the surface of the PET is fully emulsified. The formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 30% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, and continuously placing the alkaline liquid culture medium into a constant-temperature incubator at 37 ℃ and 140rpm for culture. This was repeated for 60 days.
Example 3
(1) Preparation of PET micro plastic: firstly, polyester superfine fibers and slices are refined, surface grease is removed, and the polyester superfine fibers and the slices are fully dried after being washed for multiple times; then, crushing the substrate to the size of micro plastic, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing 200ml of culture solution according to a culture formula of alkali-resistant Comamonas testosteroni in a 500ml conical flask, and adding 1% by volume of Tween 60; the system is placed in an ultrasonic instrument to ensure that the PET and the interfacial active agent are uniformly dispersed, and the system is placed on a constant temperature shaking table at 37 ℃ and 140rpm for treatment for 2 to 5 hours to ensure that the surface of the PET is fully emulsified. The formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 30% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, and continuously placing the alkaline liquid culture medium into a constant-temperature incubator at 37 ℃ and 140rpm for culture. This was repeated for 60 days.
Example 4
(1) Preparation of PET micro plastic: firstly, polyester superfine fibers and slices are refined, surface grease is removed, and the polyester superfine fibers and the slices are fully dried after being washed for multiple times; then, crushing the substrate to the size of micro plastic, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing 200ml of culture solution according to a culture formula of alkali-resistant Comamonas testosteroni in a 500ml conical flask, and adding 1% by volume of Tween 80; the system is placed in an ultrasonic instrument to ensure that the PET and the interfacial active agent are uniformly dispersed, and the system is placed on a constant temperature shaking table at 37 ℃ and 140rpm for treatment for 2 to 5 hours to ensure that the surface of the PET is fully emulsified. The formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 30% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, and continuously placing the alkaline liquid culture medium into a constant-temperature incubator at 37 ℃ and 140rpm for culture. This was repeated for 60 days.
The above is only a specific embodiment of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions or modifications made on the basis of the present invention to solve the same technical problems and achieve the same technical effects are all covered in the protection scope of the present invention.
Claims (1)
1. A method for enhancing interfacial activation for efficient biodegradation of PET comprising the steps of:
(1) preparation of PET micro plastic: firstly, polyester superfine fiber is refined, surface grease is removed, and the polyester superfine fiber is frozen and dried after being washed for many times; and then, cutting the substrate to a micro plastic size by using an ultracentrifugal cutting instrument, collecting the screened PET powder, washing with water, and drying for later use.
(2) Interface activation: preparing an alkaline liquid culture medium according to a culture formula, and adding 1% of an interfacial activator; placing the system in an ultrasonic instrument, wherein the temperature is 30 ℃, the ultrasonic frequency is 40KHz, the system works for 0.5h, so that the PET and the interfacial activator are fully and uniformly dispersed, and placing the system on a constant temperature shaking table at 37 ℃ and 140rpm for processing for 2h, so that the surface of the PET is fully emulsified; the formula of the culture medium is as follows: 1.00g/L of ammonium chloride, 1.4g/L of sodium hydroxide, 3.7g/L of potassium chloride, 0.50g/L of sodium chloride, 0.25g/L of magnesium sulfate heptahydrate, 1g/L of PET, 0.5 mu g/L of boric acid, 0.2 mu g/L of ferric chloride hexahydrate, 0.4 mu g/L of manganese sulfate pentahydrate, 0.4 mu g/L of zinc chloride, 40.0 mu g/L of copper sulfate pentahydrate and 0.2 mu g/L of ammonium molybdate.
(3) Biological-chemical combined degradation of PET (polyethylene terephthalate) micro-plastic: taking out the culture medium in the step (2), sterilizing at high temperature and high pressure for 20min, cooling to room temperature in a super clean bench, transferring into 5% bacteria solution, and culturing on a constant temperature shaking table at 37 ℃ and 140rpm for 3 days.
(4) And (4) preparing an alkaline liquid culture medium again, replacing 30% of the alkaline liquid culture medium into the degradation system in the step (3) after interface activation and sterilization, continuously placing the degradation system in a constant-temperature shaking table at 37 ℃ and 140rpm for culture, and repeating the degradation for 60 days.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118272275A (en) * | 2024-05-23 | 2024-07-02 | 佛山科学技术学院 | Microorganism for degrading PET, culture method and application thereof, and degradation method of PET |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105950473A (en) * | 2016-07-18 | 2016-09-21 | 齐齐哈尔大学 | Separation and screening method for dimethyl phthalate degradation microorganisms |
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- 2021-09-23 CN CN202111112786.2A patent/CN113750437A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105950473A (en) * | 2016-07-18 | 2016-09-21 | 齐齐哈尔大学 | Separation and screening method for dimethyl phthalate degradation microorganisms |
Non-Patent Citations (2)
| Title |
|---|
| JIXIAN GONG: "Biodegradation of Microplastic Derived from Poly(ethylene terephthalate) with Bacterial Whole-Cell Biocatalysts", 《POLYMERS》 * |
| 王宏阳: "全细胞催化PET 生物降解性能的研究", 《成都纺织高等专科学校学报》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118272275A (en) * | 2024-05-23 | 2024-07-02 | 佛山科学技术学院 | Microorganism for degrading PET, culture method and application thereof, and degradation method of PET |
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Application publication date: 20211207 |