CN116375908A - Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing - Google Patents
Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing Download PDFInfo
- Publication number
- CN116375908A CN116375908A CN202310238820.3A CN202310238820A CN116375908A CN 116375908 A CN116375908 A CN 116375908A CN 202310238820 A CN202310238820 A CN 202310238820A CN 116375908 A CN116375908 A CN 116375908A
- Authority
- CN
- China
- Prior art keywords
- polypropylene
- ash
- metal ion
- passivating agent
- washing
- 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
- -1 Polypropylene Polymers 0.000 title claims abstract description 63
- 239000004743 Polypropylene Substances 0.000 title claims abstract description 63
- 229920001155 polypropylene Polymers 0.000 title claims abstract description 63
- 238000005406 washing Methods 0.000 title claims abstract description 38
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 28
- 229910021645 metal ion Inorganic materials 0.000 title claims abstract description 28
- 239000003990 capacitor Substances 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims abstract description 15
- 239000000843 powder Substances 0.000 claims abstract description 20
- OXWDLAHVJDUQJM-UHFFFAOYSA-N 2-[[2-[2-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyloxy]ethylamino]-2-oxoacetyl]amino]ethyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate Chemical compound CC(C)(C)C1=C(O)C(C(C)(C)C)=CC(CCC(=O)OCCNC(=O)C(=O)NCCOC(=O)CCC=2C=C(C(O)=C(C=2)C(C)(C)C)C(C)(C)C)=C1 OXWDLAHVJDUQJM-UHFFFAOYSA-N 0.000 claims abstract description 12
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000001914 filtration Methods 0.000 claims abstract description 11
- 238000007731 hot pressing Methods 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- 238000003756 stirring Methods 0.000 claims abstract description 7
- 238000001816 cooling Methods 0.000 claims abstract description 5
- 238000001291 vacuum drying Methods 0.000 claims abstract description 5
- 239000000725 suspension Substances 0.000 claims abstract description 4
- 239000000203 mixture Substances 0.000 claims description 2
- 230000015556 catabolic process Effects 0.000 abstract description 6
- 238000009413 insulation Methods 0.000 abstract description 4
- 238000003760 magnetic stirring Methods 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000006701 autoxidation reaction Methods 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 230000009920 chelation Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000001603 reducing effect Effects 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000004846 x-ray emission Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
- C08F6/02—Neutralisation of the polymerisation mass, e.g. killing the catalyst also removal of catalyst residues
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/002—Details
- H01G4/018—Dielectrics
- H01G4/06—Solid dielectrics
- H01G4/14—Organic dielectrics
- H01G4/18—Organic dielectrics of synthetic material, e.g. derivatives of cellulose
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G4/00—Fixed capacitors; Processes of their manufacture
- H01G4/33—Thin- or thick-film capacitors
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/10—Homopolymers or copolymers of propene
- C08J2323/12—Polypropene
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Abstract
The invention discloses a polypropylene film ash washing method for a capacitor based on metal ion passivating agent washing, which comprises the steps of S1, respectively placing absolute ethyl alcohol, polypropylene powder and a metal ion passivating agent Naugard XL-1 into a vacuum drying oven; s2, pouring the metal ion passivating agent Naugard XL-1 in the S1 into absolute ethyl alcohol in the S1 to obtain an ash washing solution; s3, adding the polypropylene powder in the S1 into the ash washing solution in the S2 for magnetic stirring; s4, filtering the suspension in the step S3 to obtain deashing polypropylene, putting the deashing polypropylene into absolute ethyl alcohol, magnetically stirring, filtering and drying to obtain deashing polypropylene powder; s5, carrying out hot pressing on the deashing polypropylene powder in the S4, and then cooling to obtain the deashing polypropylene film sample. According to the polypropylene film ash washing method for the capacitor based on metal ion passivating agent washing, ash in polypropylene is washed by using the metal ion passivating agent, so that the ash content of the film is effectively reduced, the breakdown strength and dielectric loss performance of the film are improved, and insulation failure faults are avoided.
Description
Technical Field
The invention relates to the technical field of polypropylene film ash washing, in particular to a polypropylene film ash washing method for a capacitor based on metal ion passivating agent washing.
Background
The high-voltage direct-current capacitor is mainly used for ensuring the normal operation of a converter valve in the high-voltage direct-current power transmission system, and the safety and reliability of the high-voltage direct-current capacitor are related to success and failure of alternating-current and direct-current conversion, so that the safe and stable operation of the high-voltage direct-current power transmission system is directly determined. As the voltage class increases, the voltage class requirements for polypropylene insulation for capacitors also gradually increase. In the actual operation process, the fault of the film capacitor of the high-voltage direct-current transmission converter valve frequently occurs, and the root causes are low breakdown field strength and high dielectric loss of the insulating medium polypropylene film. The polypropylene ash contains catalyst and auxiliary agent remained in the material body, which are main factors for causing film breakdown and deterioration of dielectric loss performance.
Disclosure of Invention
The invention aims to provide a polypropylene film ash washing method for a capacitor based on metal ion passivating agent washing, which utilizes the metal ion passivating agent to wash ash in polypropylene, effectively reduces the ash content of a film, improves the breakdown strength and dielectric loss performance of the film, and avoids the occurrence of insulation failure faults.
In order to achieve the aim, the invention provides a polypropylene film ash washing method for a capacitor based on metal ion passivating agent washing, which comprises the steps of S1, respectively placing absolute ethyl alcohol, polypropylene powder and a metal ion passivating agent Naugard XL-1 into a vacuum drying oven, and drying for 20-28h at 45-55 ℃;
s2, pouring the metal ion passivating agent Naugard XL-1 in the S1 into absolute ethyl alcohol in the S1, and treating the mixture in an ultrasonic oscillator for 0.8-1.2 hours to obtain an ash washing solution;
s3, adding the polypropylene powder in the S1 and the ash washing solution in the S2 into a conical flask, and magnetically stirring at 80-120rpm on a magnetic stirrer;
s4, filtering the suspension in the step S3 to obtain deashing polypropylene, wherein the filtering aperture is 120-180 meshes, putting the deashing polypropylene into absolute ethyl alcohol, magnetically stirring for 8-12min, filtering, and drying at 55-65 ℃ to obtain deashing polypropylene powder;
s5, uniformly placing the deashing polypropylene powder in the S4 into a hot press die, hot-pressing for 2.5-4.5min at 175-185 ℃ under 18-22MPa, and cooling after hot-pressing to obtain the deashing polypropylene film sample.
Preferably, in S1, the metal ion passivating agent Naugard XL-1 is 0.01-0.15g, and the polypropylene powder is 8-12g.
Preferably, in S2, the concentration of the ash washing solution is 0.1g/100ml.
Preferably, in S3, the ash washing temperature is 35-45 ℃ and the ash washing time is 1-2h.
Preferably, in S5, the thickness of the deashing polypropylene film sample is 25-30 μm.
Therefore, the polypropylene film ash washing method for the capacitor based on metal ion passivating agent washing by adopting the method has the beneficial effects that:
1. the ash content in the polypropylene is washed by utilizing a metal ion passivating agent Naugard XL-1, so that the ash content of the deashing polypropylene film is effectively reduced, the breakdown strength and dielectric loss performance of the deashing polypropylene film are improved, and the occurrence of insulation failure faults is avoided;
2. the chelation capability of the metal ion passivating agent is utilized to effectively reduce the catalytic property of metal ash on the autoxidation of the polypropylene molecular chain, so that the inhibition on the degradation of the molecular chain is realized.
The technical scheme of the invention is further described in detail through the drawings and the embodiments.
Drawings
FIG. 1 is an ash distribution diagram of a sample of the deashed polypropylene film of example 1 and a sample of the polypropylene film of comparative example 1.
Detailed Description
The technical scheme of the invention is further described below through the attached drawings and the embodiments.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
Example 1
S1, respectively placing absolute ethyl alcohol, polypropylene powder and a metal ion passivating agent Naugard XL-1 into a vacuum drying oven, and drying at 50 ℃ for 24 hours.
S2, pouring 0.1g of the metal ion passivating agent Naugard XL-1 in S1 into 100ml of absolute ethyl alcohol in S1, and treating for 1h in an ultrasonic oscillator to obtain an ash washing solution.
S3, adding 10g of the polypropylene powder in the S1 and the ash washing solution in the S2 into a conical flask, and magnetically stirring at 80-120rpm on a magnetic stirrer.
S4, filtering the suspension in the step S3 to obtain deashing polypropylene, wherein the filtering aperture is 150 meshes, putting the deashing polypropylene into absolute ethyl alcohol, magnetically stirring for 10min, filtering, and drying at 60 ℃ to obtain the deashing polypropylene powder.
S5, placing 0.5g of the deashing polypropylene powder in the S4 into a hot press die, hot-pressing for 3min at 180 ℃ under the pressure of 20MPa, and cooling after hot-pressing to obtain the deashing polypropylene film sample.
Example 2
The ash elements of the deashed polypropylene film samples of example 1 and the polypropylene film samples of comparative example 1 were tested by X-ray fluorescence spectroscopy, and the results are shown in fig. 1, wherein fig. 1 (a) is the contents of all ash and titanium ash, and fig. 1 (b) is the contents of iron ash, magnesium ash and aluminum ash.
From FIG. 1 (a), it is seen that example 1 has a total ash content reduced to 113ppm relative to comparative example 1, and that the metal ion passivating agent Naugard XL-1 has a washing reducing effect on ash content in polypropylene.
As can be seen from FIG. 1 (b), in example 1, the ash contents of the iron ash, the magnesium ash and the aluminum ash were significantly reduced, and the ash removal efficiencies were 100%, 62.2% and 100%, respectively, as compared with comparative example 1.
Comparative example 1
S1, placing the polypropylene powder into a vacuum drying oven, and drying at 50 ℃ for 24 hours.
S2, placing 0.5g of the polypropylene powder in the S1 into a hot press die, hot-pressing for 3min at 180 ℃, wherein the pressure is 20MPa, and cooling after hot-pressing to obtain a polypropylene film sample.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting it, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that: the technical scheme of the invention can be modified or replaced by the same, and the modified technical scheme cannot deviate from the spirit and scope of the technical scheme of the invention.
Claims (5)
1. The polypropylene film ash washing method for the capacitor based on metal ion passivating agent washing is characterized by comprising the following steps of: s1, respectively placing absolute ethyl alcohol, polypropylene powder and a metal ion passivating agent Naugard XL-1 into a vacuum drying oven, and drying for 20-28h at 45-55 ℃;
s2, pouring the metal ion passivating agent Naugard XL-1 in the S1 into absolute ethyl alcohol in the S1, and treating the mixture in an ultrasonic oscillator for 0.8-1.2 hours to obtain an ash washing solution;
s3, adding the polypropylene powder in the S1 and the ash washing solution in the S2 into a conical flask, and magnetically stirring at 80-120rpm on a magnetic stirrer;
s4, filtering the suspension in the step S3 to obtain deashing polypropylene, wherein the filtering aperture is 120-180 meshes, putting the deashing polypropylene into absolute ethyl alcohol, magnetically stirring for 8-12min, filtering, and drying at 55-65 ℃ to obtain deashing polypropylene powder;
s5, uniformly placing the deashing polypropylene powder in the S4 into a hot press die, hot-pressing for 2.5-4.5min at 175-185 ℃ under 18-22MPa, and cooling after hot-pressing to obtain the deashing polypropylene film sample.
2. The method for washing ash of polypropylene film for capacitor washed by metal ion passivating agent as set forth in claim 1, wherein: in S1, the metal ion passivating agent Naugard XL-1 is 0.01-0.15g, and the polypropylene powder is 8-12g.
3. The method for washing ash of polypropylene film for capacitor washed by metal ion passivating agent as set forth in claim 1, wherein: in S2, the concentration of the ash washing solution is 0.1g/100ml.
4. The method for washing ash of polypropylene film for capacitor washed by metal ion passivating agent as set forth in claim 1, wherein: in S3, the ash washing temperature is 35-45 ℃, and the ash washing time is 1-2h.
5. The method for washing ash of polypropylene film for capacitor washed by metal ion passivating agent as set forth in claim 1, wherein: in S5, the thickness of the deashing polypropylene film sample is 25-30 μm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310238820.3A CN116375908A (en) | 2023-03-13 | 2023-03-13 | Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310238820.3A CN116375908A (en) | 2023-03-13 | 2023-03-13 | Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116375908A true CN116375908A (en) | 2023-07-04 |
Family
ID=86970345
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310238820.3A Pending CN116375908A (en) | 2023-03-13 | 2023-03-13 | Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116375908A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4197398A (en) * | 1974-12-04 | 1980-04-08 | Exxon Research & Engineering Co. | Process for neutralizing and deashing polypropylene |
| CN113621096A (en) * | 2021-07-06 | 2021-11-09 | 雷剑兰 | Ultra-low ash polyolefin, preparation method and application |
| CN115612005A (en) * | 2022-11-09 | 2023-01-17 | 山东京博石油化工有限公司 | Efficient solvent deashing treatment method for polypropylene resin |
-
2023
- 2023-03-13 CN CN202310238820.3A patent/CN116375908A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4197398A (en) * | 1974-12-04 | 1980-04-08 | Exxon Research & Engineering Co. | Process for neutralizing and deashing polypropylene |
| CN113621096A (en) * | 2021-07-06 | 2021-11-09 | 雷剑兰 | Ultra-low ash polyolefin, preparation method and application |
| CN115612005A (en) * | 2022-11-09 | 2023-01-17 | 山东京博石油化工有限公司 | Efficient solvent deashing treatment method for polypropylene resin |
Non-Patent Citations (1)
| Title |
|---|
| BOXUE DU等: "Dielectric Breakdown Performance of Deashed Polypropylene for HVDC Film Capacitors", 《IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION》, vol. 29, no. 6, pages 2209 - 2217, XP011931231, DOI: 10.1109/TDEI.2022.3203659 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Liu et al. | Enhanced enzymatic hydrolysis and structural features of corn stover by FeCl3 pretreatment | |
| CN103724189B (en) | Microwave cooperating catalytic liquefaction lignin degrading prepares the method for single phenolic compound | |
| CN105957716B (en) | A kind of methanol electrolyte for electrolytic capacitor and preparation method thereof | |
| CN116375908A (en) | Polypropylene film ash washing method for capacitor based on metal ion passivating agent washing | |
| DE102008059373A1 (en) | Solid electrolytic capacitor and process for its production | |
| CN101556866A (en) | High-end large-scale aluminum electrolysis capacitor and preparation method thereof | |
| CN108505094B (en) | Formation method for reducing leakage current of electrode foil | |
| CN110556783B (en) | Zero sequence overcurrent protection method and device for transformer | |
| CN107527742A (en) | Electrolyte for low-corrosivity electrolytic capacitor and manufacturing method thereof | |
| CN102964577A (en) | High-temperature-resistant rosin modified resin and production method thereof | |
| CN110993346A (en) | Ultra-low impedance aluminum electrolytic capacitor for switching power supply | |
| CN108257786A (en) | A kind of resistance to big ripple electrolyte for capacitor of contracting body | |
| CN110818539B (en) | Method for purifying diethylene glycol monobutyl ether reagent from waste stripping liquid | |
| CN108847668A (en) | A kind of harmonic wave active filter circuit inhibiting factory 400V distribution system | |
| KR102369396B1 (en) | Pre-processing method for manufacturing electronic aluminum foil including TiO2 media layer | |
| KR102591669B1 (en) | Compositions, polymers for capacitors and capacitors | |
| CN111961015B (en) | Method for preparing 2,5-furandimethanol by catalyzing 5-hydroxymethylfurfural | |
| CN104941646B (en) | A kind of heavy naphtha catalytic reforming prepares high-knock rating gasoline catalyst | |
| CN113322454A (en) | Forming method of low-pressure formed foil and prepared low-pressure formed foil | |
| CN113539693B (en) | Method for reducing loss of high-voltage aluminum electrolytic capacitor | |
| CN113076646A (en) | Calculation method for ground parameters of neutral point of hydraulic generator | |
| CN106320098B (en) | Resin compounded mica paper and preparation method thereof | |
| CN113972072B (en) | 16V solid-state capacitor and manufacturing method thereof | |
| CN117399020B (en) | Magnetic catalyst containing erbium and copper, preparation method and method for catalyzing and synthesizing lactic acid by using magnetic catalyst | |
| CN115925516B (en) | Preparation method of aluminum isopropoxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |