CN-122013251-A - Membrane electrode catalytic layer stripping device and method, failure detection method and catalytic layer recovery method

CN122013251ACN 122013251 ACN122013251 ACN 122013251ACN-122013251-A

Abstract

The invention discloses a membrane electrode catalytic layer stripping device, a method, a failure detection method and a catalytic layer recovery method, wherein the device comprises a solvent supply unit, a pressure control unit, a stripping cabin and a waste liquid recovery unit, wherein the solvent supply unit comprises an organic reagent storage tank, a pipeline and an ultrasonic atomizer which are sequentially connected, the output end of the ultrasonic atomizer is connected with an atomized gas conveying pipeline, the pressure control unit comprises a hydraulic execution module and a heating module, the output pressure and the output temperature of the pressure control unit are adjustable, the stripping cabin comprises an end plate provided with a micro-channel, an elastic sealing assembly and a porous plate, the end plate is arranged opposite to the porous plate and forms a pressurizable sealing chamber through the elastic sealing assembly, the inner surface of the end plate and the inner wall of the micro-channel are coated with polytetrafluoroethylene coating, and the waste liquid recovery unit is connected to an exhaust/liquid port of the stripping cabin through a pipeline, wherein the porous plate is used for bearing and contacting a catalytic layer of a membrane electrode to be stripped.

Inventors

HE DONGXU
LI QIANG
SUN HAORAN
CHEN MING
ZHOU KEHAN
LIU YUMEI
ZHANG YING

Assignees

东方电气集团东方锅炉股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260121

Claims (10)

1. A membrane electrode catalytic layer peeling apparatus, characterized by comprising: the solvent supply unit comprises an organic reagent storage tank and a pipeline which are connected in sequence; the pressure control unit comprises a hydraulic execution module and a heating module, and the output pressure and the output temperature of the pressure control unit are adjustable; The stripping cabin comprises an end plate provided with a micro-channel, an elastic sealing assembly and a porous plate, wherein the end plate is arranged opposite to the porous plate, a sealing chamber capable of being pressurized is formed through the elastic sealing assembly, and polytetrafluoroethylene coatings are coated on the inner surface of the end plate and the inner wall of the micro-channel; a waste liquid recovery unit connected to an exhaust/liquid port of the peeling chamber through a pipeline; wherein the porous plate is used for bearing and contacting the catalytic layer surface of the membrane electrode to be peeled.
2. The membrane electrode assembly peeling apparatus according to claim 1, wherein the porous plate has a gradient pore diameter structure in which pore diameters gradually decrease from a side facing the end plate to a side facing the catalyst layer.
3. The membrane electrode assembly according to claim 2, wherein the porous plate has a pore diameter of 100.+ -.10. Mu.m, on the side facing the end plate, and a pore diameter of 10.+ -.2. Mu.m, on the side facing the catalyst layer, and the surface of the porous plate in contact with the catalyst layer is subjected to acid treatment to form a roughened surface.
4. The membrane electrode assembly peeling apparatus according to claim 1, wherein the pressure control unit has an output pressure ranging from 0 to 30 tons of force and an output temperature ranging from room temperature to 200 ℃.
5. The membrane electrode assembly peeling apparatus according to claim 1, wherein the micro flow channels on the end plate are uniformly distributed for uniformly introducing the atomized organic solvent into the sealed chamber.
6. A membrane electrode catalytic layer peeling method using the peeling apparatus according to any one of claims 1 to 5, characterized by comprising the steps of: (a) Clamping pretreatment, namely placing a membrane electrode to be treated in a sealed cavity of the stripping cabin, so that an anode catalytic layer and a cathode catalytic layer of the membrane electrode are respectively contacted with the porous plates at two sides; (b) Applying pressure by the pressure control unit to the peeling chamber; (c) Solvent infiltration wetting by passing the organic solvent into the sealed chamber of the stripping chamber for a predetermined period of time (D) Transferring the catalytic layer, namely stripping the catalytic layer from the proton exchange membrane and transferring the catalytic layer to the porous plate by utilizing the difference of swelling degrees of the proton exchange membrane and the catalytic layer in an organic solvent and the mechanical anchoring effect under pressure; (e) And (3) removing the solvent, namely heating the stripping cabin through a heating module of the pressure control unit, volatilizing and removing the organic solvent to respectively obtain an anode catalytic layer, a cathode catalytic layer and an independent proton exchange membrane which are loaded on a porous plate.
7. The method according to claim 6, wherein in the step (b), the axial pressure is 1.2 to 6MPa to make the compression amount of the elastic sealing member 20 to 35%, in the step (C), the flow rate of the atomized organic solvent is 50 to 100mL/min, the holding time is 10 to 15 minutes, and in the step (e), the heating temperature is 40 to 70 ℃ and the holding time is 20 to 30 minutes.
8. A failure detection method suitable for a proton exchange membrane electrolytic water film electrode is characterized by comprising the following steps: the method as claimed in claim 6 or 7 is used for completely stripping and obtaining an anode catalytic layer, a cathode catalytic layer and a proton exchange membrane from a normal membrane electrode and a failure membrane electrode respectively; Cross-combining the normal membrane electrode and each component of the failure membrane electrode, and hot-pressing again to assemble a plurality of different membrane electrode assemblies for testing; And determining specific components and failure reasons which cause the performance degradation of the failure membrane electrode by comparing and analyzing the performance difference of each membrane electrode assembly for testing.
9. The failure detection method according to claim 8, wherein the cross-over combination specifically includes: assembling a first reference membrane electrode assembly (MEA-0) with a normal anode catalytic layer, a normal proton exchange membrane and a normal cathode catalytic layer; assembling a second test membrane electrode assembly (MEA-1) with the spent anode catalytic layer, the normal proton exchange membrane and the normal cathode catalytic layer; Assembling a third test membrane electrode assembly (MEA-2) with the normal anode catalytic layer, the spent proton exchange membrane and the normal cathode catalytic layer; a fourth test membrane electrode assembly (MEA-3) was assembled using a normal anode catalytic layer, a normal proton exchange membrane and a spent cathode catalytic layer.
10. The catalytic layer recovery method suitable for the proton exchange membrane electrolytic water film electrode is characterized by comprising the following steps of: Completely stripping and obtaining a spent anode catalytic layer and a spent cathode catalytic layer supported on a porous plate from a spent membrane electrode by the method of claim 6 or 7; And recombining the invalid anode catalytic layer, the invalid cathode catalytic layer and a normal proton exchange membrane through a hot pressing process to form a regenerated membrane electrode assembly capable of working normally, thereby realizing recycling of the catalytic layer.

Description

Membrane electrode catalytic layer stripping device and method, failure detection method and catalytic layer recovery method Technical Field The invention relates to the technical field of water electrolysis hydrogen production, in particular to a membrane electrode catalytic layer stripping device, a membrane electrode catalytic layer stripping method, a failure detection method and a catalytic layer recovery method. Background The technology of producing hydrogen by electrolysis of water is one of the most potential paths for achieving the 'double carbon target', wherein the proton exchange membrane water electrolysis PEMWE technology has been greatly developed in recent years due to the advantages of long service life, good fluctuation resistance and the like. And degradation of the performance of the membrane electrode is the most leading cause of the failure of the PEMWE electrolyzer. The possible causes of degradation or failure of the membrane electrode are very various and complex, such as cathode/anode catalytic layer failure (catalytic layer shedding, catalytic layer poisoning, ionomer loss, etc.), proton exchange membrane failure (perforation, proton conductivity reduction), etc. The accurate locking of the position of the failure of the electrolyzer or the membrane electrode and the mechanism are of great significance to the design, production and long-term operation of commercial PEM electrolyzer products, but the prior art lacks reliable means of correlation. CN108107090a proposes a method for detecting membrane electrode pollution of a solid polymer electrolyte water electrolysis cell, which specifically comprises the steps of detecting the voltage of the electrolysis cell in a current mode, observing whether the voltage is stepped, detecting the electrochemical alternating current impedance performance of the electrolysis cell, judging whether the performance attenuation is caused by pollution by combining the step change of the voltage and the internal resistance, and judging whether the obvious step change occurs to the increase of the internal resistance. The method can accurately and effectively evaluate whether the membrane electrode is deteriorated. However, the position and cause of the deterioration cannot be further confirmed. CN114678553a and CN118983457a propose a method for recycling the electrolyte membrane electrode of the waste proton exchange membrane, which comprises immersing the waste membrane electrode in alcohol/water, peeling the catalyst layer from the proton exchange membrane by ultrasound, scraping and flushing, washing the proton exchange membrane with solvent, regenerating the proton exchange membrane, collecting liquid suspended matters, filtering, centrifuging to obtain catalyst filter residues, and recycling the filtrate. Both methods focus on catalyst recovery, and although physicochemical tests can be carried out on the catalyst washed out from the membrane electrode on the basis of the method, possible failure reasons of the membrane electrode structure and the process level are difficult to trace. The prior art methods have the problems that physical and chemical analysis can only be carried out after the membrane electrode is integrally detected or completely destroyed, and structural problems (such as insufficient local proton conductivity, uneven film thickness distribution, local perforation and the like of a proton exchange membrane) of the electrolytic cell or the membrane electrode cannot be fed back, so that obvious restrictions exist on the research and development and operation of commercial PEM electrolytic cell products. Currently, the technology of PEM electrolyzed water technology is in commercial landing, but the failure detection of product-grade PEM membrane electrodes still lacks reliable technical means, which seriously hinders the technical development of related products. Disclosure of Invention Accordingly, the present invention is directed to a stripping device, a stripping method, a failure detection method and a recovery method for a catalytic layer of a membrane electrode, which are aimed at overcoming at least one related technical problem in the prior art. The method and the device can completely peel off the catalytic layer and accurately and comprehensively evaluate the failure position and failure mechanism of the membrane electrode. In addition, the method can also directly realize the dry recovery of the catalyst, avoid the use of a large amount of organic solvents in the method disclosed by the related patent, and is more environment-friendly and efficient. In order to achieve the above purpose, the present invention adopts the following technical scheme: In a first aspect, the present application provides a membrane electrode catalytic layer stripping device, comprising: the solvent supply unit comprises an organic reagent storage tank and a pipeline which are connected in sequence; the pressure control unit comprises a hyd