CN111644071A - Preparation method of graphene oxide nanofiltration membrane suitable for operation under high operating pressure - Google Patents
Preparation method of graphene oxide nanofiltration membrane suitable for operation under high operating pressure Download PDFInfo
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- CN111644071A CN111644071A CN202010521140.9A CN202010521140A CN111644071A CN 111644071 A CN111644071 A CN 111644071A CN 202010521140 A CN202010521140 A CN 202010521140A CN 111644071 A CN111644071 A CN 111644071A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0079—Manufacture of membranes comprising organic and inorganic components
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/10—Supported membranes; Membrane supports
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/10—Supported membranes; Membrane supports
- B01D69/105—Support pretreatment
Abstract
The invention discloses a preparation method of a graphene oxide nanofiltration membrane suitable for running under high operating pressure. The graphene oxide nanofiltration membrane prepared by the invention has better separation performance and stability under the operation pressure of more than 0.2MPa, and can meet the application requirement of the graphene oxide nanofiltration membrane under high operation pressure.
Description
Technical Field
The invention relates to a preparation method of a nanofiltration membrane, and particularly relates to a preparation method of a graphene oxide nanofiltration membrane suitable for operation under high operating pressure.
Background
The nanofiltration technology is a membrane separation technology separated from the reverse osmosis technology, and is a continuation and development branch of the ultra-low pressure reverse osmosis technology. For a long time in the past, nanofiltration membranes have been referred to as ultra low pressure reverse osmosis membranes or selective reverse osmosis membranes or loose reverse osmosis membranes. Japanese scholars have specifically defined the separation performance of nanofiltration membranes: the membrane with the operation pressure less than or equal to 1.50mPa, the cut-off molecular weight of 200-1000 and the NaCl cut-off rate less than or equal to 90 percent can be regarded as a nanofiltration membrane. At present, the nanofiltration technology has been separated from the reverse osmosis technology, becomes an independent separation technology between the ultrafiltration technology and the reverse osmosis technology, is widely applied to various fields such as seawater desalination, ultrapure water manufacture, food industry, environmental protection and the like, and becomes an important branch in the membrane separation technology.
Graphene oxide, as a new two-dimensional inorganic nano material, has been widely applied in the preparation of functional materials due to its own physicochemical properties. At present, it has become a common technology to apply graphene oxide to a modified membrane material or directly use graphene oxide as a membrane material, for example, graphene oxide is added to an aqueous phase interface to prepare a polyamide membrane, graphene oxide is added to a PVDF membrane casting solution as an additive to prepare a PVDF composite membrane by a blending method, or graphene is fixed on a support by a layer-by-layer self-assembly method to directly serve as a filtration membrane. In the method, for directly using graphene as a nanofiltration membrane, products prepared in the prior art can only be used in a low-pressure range, generally not more than 0.2Mpa, so that the application range of the graphene nanofiltration membrane is limited. In order to improve the application potential of the graphene nanofiltration membrane, a new preparation method of the graphene nanofiltration membrane is urgently needed to solve the problems.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides a preparation method of a graphene oxide nanofiltration membrane suitable for operation under high operating pressure.
The invention provides a preparation method of a graphene oxide nanofiltration membrane suitable for running under high operating pressure, which is characterized by comprising the following steps: the preparation method comprises the steps of blending a polymer and a hydrophilic molecular sieve to prepare a support body, carrying out acyl chlorination modification on the support body, and sequentially dipping the support body modified by acyl chloride into an amino-modified graphene oxide aqueous phase solution and an organic phase solution containing acyl chloride to enable the interface of the support body modified by acyl chloride to be polymerized to form the graphene oxide nanofiltration membrane.
Specifically, the method comprises the following steps:
(1) preparation of support body by blending method
Mixing a polymer, a solvent, an additive and a hydrophilic molecular sieve, stirring, standing, defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, solidifying in a coagulating bath to form a membrane, soaking in deionized water, drying at high temperature, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in an organic solvent containing an aromatic polyacyl chloride compound for 1-4h, removing the surface solution after finishing dipping, and drying at 40-80 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution for 10-20min, dipping the modified support body in an organic phase solution containing aromatic polybasic acyl chloride again, and performing thermal crosslinking at 60-80 ℃ for 10-30min after dipping to obtain the graphene oxide nanofiltration membrane.
Specifically, the polymer is one of polysulfone, polyethersulfone, cellulose acetate, nylon and polyvinylidene fluoride.
Specifically, the hydrophilic molecular sieve is one of NaA, NaY and ZSM-5.
Specifically, the mass ratio of the polymer to the hydrophilic molecular sieve in the step (1) is 2:1-4: 1.
Specifically, the aromatic polybasic acyl chloride compound in the step (2) and the aromatic polybasic acyl chloride in the step (3) are selected from one or more of isophthaloyl dichloride, terephthaloyl dichloride and phthaloyl dichloride, and the aromatic polybasic acyl chloride compound in the step (2) and the aromatic polybasic acyl chloride in the step (3) can be the same or different.
Specifically, the amino-modified graphene is prepared by dehydration condensation reaction of graphene oxide and ethylenediamine.
Specifically, the high operating pressure means an operating pressure of 0.2 to 1.5MPa, preferably 0.5 to 1 MPa.
Compared with the prior art, the application strength of the graphene oxide nanofiltration membrane is improved in an interfacial polymerization mode by crosslinking the acyl chloride compound in a transverse and longitudinal mode. Firstly, in the horizontal direction, the amino modified graphene oxide is crosslinked into a net through the crosslinking action of an acyl chloride compound, in the longitudinal direction, the amino modified graphene and the support body are crosslinked together through the acyl chloride modification of the support body, the direct bonding force of the separation layer and the support body is improved, and the hydroxyl group of the support body is crosslinked with acyl chloride by adding a hydrophilic molecular sieve on the support body, so that the acyl chloride degree of the support body is improved, and the flux of the nanofiltration membrane is increased to a certain extent.
Detailed Description
Preparation of aminated graphene used in the following examples/and or comparative examples: mixing graphene oxide and dimethylformamide, carrying out ultrasonic treatment for 2h, adding ethylenediamine and dicyclohexylcarbodiimide, continuing to carry out ultrasonic treatment for 10min, reacting for 24h at 120 ℃, adding ethanol, standing for 12h, filtering and cleaning thick slurry at the bottom, and drying in an oven at 60 ℃ to obtain aminated graphene oxide for later use, wherein the mass ratio of the graphene oxide to the dimethylformamide to the ethylenediamine to the dicyclohexylcarbodiimide is 1:100:150: 25.
Example 1:
(1) preparation of support body by blending method
Mixing PVDF, dimethylacetamide, polyethylene glycol and NaA molecular sieve (the ratio of silicon to aluminum is 1) according to the mass ratio of 10:120:1:3, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the glass sheet in deionized water, drying the glass sheet at a high temperature of 60 ℃, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in n-hexane containing 0.5wt% of isophthaloyl dichloride, wherein the dipping time is 2h, removing the surface solution after the dipping is finished, and drying at 60 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution (0.5 wt%, adjusting the pH to 11 by adopting NaOH), wherein the dipping time is 10min, dipping the modified support body in n-hexane containing 0.2wt% of isophthaloyl dichloride, and after the dipping is finished, performing thermal crosslinking at 80 ℃ for 30min to obtain the graphene oxide nanofiltration membrane.
Example 2
(1) Preparation of support body by blending method
Mixing PVDF, dimethylacetamide, polyethylene glycol and ZSM-5 molecular sieve (the ratio of silicon to aluminum is 40) according to the mass ratio of 10:120:1:3, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the glass sheet into deionized water, drying the glass sheet at a high temperature of 60 ℃, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in n-hexane containing 0.5wt% of isophthaloyl dichloride, wherein the dipping time is 2h, removing the surface solution after the dipping is finished, and drying at 60 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution (0.5 wt%, adjusting the pH to 11 by adopting NaOH), wherein the dipping time is 10min, dipping the modified support body in n-hexane containing 0.2wt% of isophthaloyl dichloride, and after the dipping is finished, performing thermal crosslinking at 80 ℃ for 30min to obtain the graphene oxide nanofiltration membrane.
Example 3
(1) Preparation of support body by blending method
Mixing PVDF, dimethylacetamide, polyethylene glycol and NaY molecular sieve (the ratio of silicon to aluminum is 6) according to the mass ratio of 10:120:1:3, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the glass sheet in deionized water, drying the glass sheet at a high temperature of 60 ℃, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in n-hexane containing 0.5wt% of isophthaloyl dichloride, wherein the dipping time is 2h, removing the surface solution after the dipping is finished, and drying at 60 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution (0.5 wt%, adjusting the pH to 11 by adopting NaOH), wherein the dipping time is 10min, dipping the modified support body in n-hexane containing 0.2wt% of isophthaloyl dichloride, and after the dipping is finished, performing thermal crosslinking at 80 ℃ for 30min to obtain the graphene oxide nanofiltration membrane.
Comparative example 1
(1) Preparation of the support
Mixing PVDF, dimethylacetamide and polyethylene glycol according to a mass ratio of 10:120:1, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the membrane in deionized water, and drying the membrane at a high temperature of 60 ℃ to form a membrane as a support for later use;
(2) preparation of graphene oxide nanofiltration membrane
And (2) dipping the modified support body prepared in the step (1) in an amino-modified graphene oxide aqueous solution (0.5 wt%, adjusting the pH to 11 by adopting NaOH), wherein the dipping time is 10min, dipping the modified support body in n-hexane containing 0.2wt% of isophthaloyl dichloride, and after the dipping is finished, performing thermal crosslinking at 80 ℃ for 30min to obtain the graphene oxide nanofiltration membrane.
Comparative example 2
(1) Preparation of support body by blending method
Mixing PVDF, dimethylacetamide, polyethylene glycol and NaA molecular sieve (the ratio of silicon to aluminum is 1) according to the mass ratio of 10:120:1:3, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the glass sheet in deionized water, drying the glass sheet at a high temperature of 60 ℃, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in n-hexane containing 0.5wt% of isophthaloyl dichloride, wherein the dipping time is 2h, removing the surface solution after the dipping is finished, and drying at 60 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) fixing the modified support body prepared in the step (2) in a suction filtration device, adding an amino modified graphene oxide aqueous solution (0.5 wt%, adding sodium hydroxide to adjust the pH value to 11) into a filter cup, and performing vacuum suction filtration for 10min to form a film.
Comparative example 3
(1) Preparation of the support
Mixing PVDF, dimethylacetamide and polyethylene glycol according to a mass ratio of 10:120:1, stirring, standing and defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, placing the glass sheet into water to solidify and form a membrane, soaking the membrane in deionized water, and drying the membrane at a high temperature of 60 ℃ to form a membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in n-hexane containing 0.5wt% of isophthaloyl dichloride, wherein the dipping time is 2h, removing the surface solution after the dipping is finished, and drying at 60 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution (0.5 wt%, adjusting the pH to 11 by adopting NaOH), wherein the dipping time is 10min, dipping the modified support body in n-hexane containing 0.2wt% of isophthaloyl dichloride, and after the dipping is finished, performing thermal crosslinking at 80 ℃ for 30min to obtain the graphene oxide nanofiltration membrane.
The nanofiltration membrane samples prepared in examples 1 to 3 and comparative examples 1 to 3 were subjected to 0.8Mpa pure water flux, NaCl and Na2SO4 rejection tests, and the data were measured at two time points of 0 h and 24h, respectively, with the results shown in the following table.
As can be seen from the above table, the nanofiltration membrane sample prepared by the preparation method provided by the invention has the advantages that the membrane performance (including flux and rejection rate) is not reduced basically with the passage of time under high operation pressure, while the comparative sample shows that the membrane performance is reduced seriously, so that the method provided by the invention can realize separation under high operation pressure to a certain extent.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the invention, but rather the intention is to cover all modifications, alternatives, and equivalents falling within the spirit and scope of the invention.
Claims (8)
1. A preparation method of a graphene oxide nanofiltration membrane suitable for running under high operating pressure is characterized by comprising the following steps: the preparation method comprises the steps of blending a polymer and a hydrophilic molecular sieve to prepare a support body, carrying out acyl chlorination modification on the support body, and then sequentially dipping the support body modified by acyl chloride into an amino-modified graphene oxide aqueous solution and an organic solution containing acyl chloride to enable the interface of the support body modified by the acyl chloride to be polymerized to form the graphene oxide nanofiltration membrane.
2. Method according to claim 1, characterized in that the method comprises the steps of:
(1) preparation of support body by blending method
Mixing a polymer, a solvent, an additive and a hydrophilic molecular sieve, stirring, standing, defoaming to form a membrane casting solution, scraping a membrane on a glass sheet, solidifying in a coagulating bath to form a membrane, soaking in deionized water, drying at high temperature, and forming the membrane as a support for later use;
(2) modification of support by acid chlorination
Dipping the surface of the support prepared in the step (1) in an organic solvent containing an aromatic polyacyl chloride compound for 1-4h, removing the surface solution after finishing dipping, and drying at 40-80 ℃;
(3) preparation of graphene oxide nanofiltration membrane
And (3) dipping the modified support body prepared in the step (2) in an amino-modified graphene oxide aqueous solution for 10-20min, dipping the modified support body in an organic phase solution containing aromatic polybasic acyl chloride again, and performing thermal crosslinking at 60-80 ℃ for 10-30min after dipping to obtain the graphene oxide nanofiltration membrane.
3. The method of claim 1, wherein the polymer is one of polysulfone, polyethersulfone, cellulose acetate, nylon, polyvinylidene fluoride.
4. The method of claim 1, wherein the hydrophilic molecular sieve is one of NaA, NaY, ZSM-5.
5. The method according to claim 1, wherein the mass ratio of the polymer to the hydrophilic molecular sieve in step (1) is 2:1 to 4: 1.
6. The method according to claim 1, wherein the aromatic poly-acid chloride compound in step (2) and the aromatic poly-acid chloride in step (3) are selected from one or more of isophthaloyl dichloride, terephthaloyl dichloride and phthaloyl dichloride, and the aromatic poly-acid chloride compound in step (2) and the aromatic poly-acid chloride in step (3) may be the same or different.
7. The method according to claim 1, wherein the amino-modified graphene is prepared by dehydration condensation reaction of graphene oxide and ethylenediamine.
8. The process according to claim 1, wherein said high operating pressure means an operating pressure of 0.2 to 1.5MPa, preferably 0.5 to 1 MPa.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114931858A (en) * | 2022-05-30 | 2022-08-23 | 山西大学 | High-flux graphene oxide composite membrane and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106139923A (en) * | 2015-04-16 | 2016-11-23 | 中国科学院上海高等研究院 | A kind of graphene oxide framework material composite membrane and its preparation method and application |
| CN106823842A (en) * | 2017-03-28 | 2017-06-13 | 天津大学 | A kind of preparation method of graphene oxide composite nano filter membrane |
| CN108404688A (en) * | 2018-03-29 | 2018-08-17 | 同济大学 | A kind of modified semi-aromatic polyamide film and preparation method thereof |
| KR20200033650A (en) * | 2018-09-20 | 2020-03-30 | 광주과학기술원 | graphene oxide membrane film and method for fabricating the same |
-
2020
- 2020-06-10 CN CN202010521140.9A patent/CN111644071A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106139923A (en) * | 2015-04-16 | 2016-11-23 | 中国科学院上海高等研究院 | A kind of graphene oxide framework material composite membrane and its preparation method and application |
| CN106823842A (en) * | 2017-03-28 | 2017-06-13 | 天津大学 | A kind of preparation method of graphene oxide composite nano filter membrane |
| CN108404688A (en) * | 2018-03-29 | 2018-08-17 | 同济大学 | A kind of modified semi-aromatic polyamide film and preparation method thereof |
| KR20200033650A (en) * | 2018-09-20 | 2020-03-30 | 광주과학기술원 | graphene oxide membrane film and method for fabricating the same |
Non-Patent Citations (1)
| Title |
|---|
| 刘梦欣等: "《改性氧化石墨烯接枝聚酰胺纳滤膜》", 《膜科学与技术》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114931858A (en) * | 2022-05-30 | 2022-08-23 | 山西大学 | High-flux graphene oxide composite membrane and preparation method and application thereof |
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