A method to accelerate the activation rate of an electrolytic reactor

Abstract

This invention discloses a method for accelerating the activation rate of an electrolytic reactor, comprising: S1: introducing deionized water to both the hydrogen and oxygen sides of the electrolytic reactor at a temperature of T0, keeping the electrodes of the electrolytic reactor fully wetted; S2: performing electrolytic reactor activation operation using a constant voltage strategy, controlling the average single cell temperature of the electrolytic reactor to V1, at which point the outlet water temperature of the electrolytic reactor is T1, and adjusting the outlet hydrogen pressure and oxygen pressure to P1 and P2, respectively; S3: under the set average single cell temperature V1, as the operating time increases, the outlet water temperature of the electrolytic reactor gradually increases, the current density continues to increase, and the outlet hydrogen pressure and oxygen pressure are maintained at P1 and P2; S4: waiting for the outlet water temperature of the electrolytic reactor to rise to the specified operating temperature T. end The process is allowed to stabilize for a period of time until the average single-cell voltage of the electrolytic reactor does not change significantly, thus completing the activation operation.

Description

Technical Field

[0001] This invention relates to the field of electrolytic reactor technology, and in particular to a method for accelerating the activation rate of an electrolytic reactor. Background Technology

[0002] An electrolytic reactor is an energy conversion device that directly converts electrical energy into chemical energy through electrocatalytic reactions at the electrodes. To ensure that the electrolytic reactor can quickly reach its optimal performance during operation, the electrodes in the reactor generally need to be activated under given conditions after assembly. The activation process and mechanism of an electrolytic reactor are very complex, involving six processes simultaneously: humidification of the proton exchange membrane, establishment of electron transport channels, establishment of proton transport channels, establishment of gas transport channels, establishment of water transport channels, and optimization of the electrode structure. Currently, completing the activation of an electrolytic reactor requires a considerable amount of time, typically tens of hours. Commonly used electrolytic reactor activation methods include: 1. Constant current activation; 2. Combined activation using "constant voltage" and "constant current"; 3. Water-controlled temperature activation, etc. All of these activation methods are carried out under atmospheric pressure conditions with hydrogen and oxygen production, and the activation time is as long as 24 to 48 hours. Even though improved combined activation can shorten the activation time of the electrolytic reactor to 4 to 12 hours, the current activation time of the electrolytic reactor still cannot meet the needs of mass production of electrolytic reactors. Summary of the Invention

[0003] In view of the problems existing in the prior art, the present invention discloses a method for accelerating the activation rate of an electrolytic reactor, which specifically includes the following steps:

[0004] S1: Deionized water is introduced to both the hydrogen and oxygen sides of the electrolytic reactor, and the temperature of the deionized water is controlled at T0 to keep the electrodes of the electrolytic reactor fully wetted.

[0005] S2: The constant voltage strategy is used to activate the electrolytic reactor, and the average single cell of the electrolytic reactor is controlled to be V1. At this time, the outlet water temperature of the electrolytic reactor is T1, and the outlet hydrogen pressure and oxygen pressure of the electrolytic reactor are adjusted to P1 and P2 respectively.

[0006] S3: Under the set average single cell V1, as the operating time increases, the outlet water temperature of the electrolyzer gradually increases, the current density continues to increase, and the outlet hydrogen pressure and oxygen pressure are maintained at P1 and P2.

[0007] S4: Waiting for the outlet water temperature of the electrolytic reactor to rise to the designated operating temperature T end The activation process is completed when the average single-cell voltage of the electrolytic reactor remains stable for a period of time until it does not change significantly.

[0008] Furthermore, in S1: the temperature of deionized water T0 does not exceed 40℃, and T1 and T2 are controlled. endThe temperature should be not lower than T0 and not exceed 90℃, and the water flow rate should be calculated based on the active area of ​​a single electrolytic reactor cell, ranging from 0.5 to 5 mL / min. -1 ·cm -2 The water flow should be maintained for 3 to 30 minutes.

[0009] Furthermore, in S2, the average voltage V1 of a single cell in the electrolytic reactor ranges from 1.7 to 1.9V, with a maximum single-cell voltage limit of V. max No more than 1.95V.

[0010] Furthermore, in S3, the hydrogen and oxygen pressures at the electrolytic reactor outlet are P1 and P2, respectively, ranging from 0.2 to 1 MPa, and are maintained for 3 to 30 minutes.

[0011] Furthermore, in S4, the specified operating temperature range for the electrolytic reactor is 50 to 90°C. If the average single-cell voltage change of the electrolytic reactor is not higher than 5mV / min at the specified operating temperature, the activation process is complete.

[0012] By employing the above-mentioned technical solution, this invention provides a method for accelerating the activation rate of an electrolytic reactor. This method controls the upper limit of the voltage of a single cell in the electrolytic reactor but does not limit the current value. While ensuring the safety of the electrolytic reactor, it maximizes the relaxation of restrictions on the electrolytic current, significantly shortening the activation time and enabling rapid completion of the activation process for a single electrolytic reactor, thereby greatly increasing the speed of reactor delivery. Furthermore, this method uses a constant voltage strategy to gradually increase the water temperature, eliminating the need for additional auxiliary heating devices; the entire activation process can be completed using only a normal test bench. By gradually operating the electrolytic cell at a high current density, the water generated from the reaction rapidly humidifies the membrane electrode, eliminating unstable catalysts on the electrode surface and oxidizing impurities, thus achieving rapid activation of the membrane electrode. This allows the electrode to quickly form stable gas and electron transport channels, accelerating the activation of the electrolytic reactor.

[0013] This invention controls the hydrogen and oxygen pressure at the outlet of the electrolytic reactor and appropriately increases the hydrogen and oxygen production pressure, which can significantly compress the gas volume inside the electrolytic reactor. This can effectively reduce the erosion of the electrodes and catalysts whose microstructures are not yet stable due to the generation and breakage of bubbles during the activation of the electrolytic reactor, and effectively protect the electrodes. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1This is a flowchart of the method for accelerating the activation rate of an electrolytic reactor according to the present invention;

[0016] Figure 2 Comparison of electrolytic reactor polarization curves measured under the conditions of Example 1;

[0017] Figure 3 Comparison of electrolytic reactor polarization curves measured under the conditions of Example 2;

[0018] Figure 4 Comparison of electrolytic reactor polarization curves measured under the conditions of Comparative Example 1. Detailed Implementation

[0019] To make the technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention:

[0020] like Figure 1 The method described here accelerates the activation rate of an electrolytic reactor. First, pre-activation is performed to eliminate unstable catalysts on the electrode surface and oxidize impurities, thus achieving rapid activation of the membrane electrode. Then, a constant-voltage variable-current activation method is used to rapidly humidify the membrane electrode with the water generated in the reaction, achieving rapid humidification of the proton exchange membrane and catalyst layer resin. By controlling the electrolytic reactor to operate at alternating high and low current densities, stable gas and electron transport channels can be rapidly formed on the electrodes, accelerating the activation of the electrolytic reactor and resulting in stable reactor performance.

[0021] Example 1

[0022] Under the superior operating conditions of this technical solution, the single-cell voltage of the electrolytic reactor is kept constant at 1.85V during activation, and the hydrogen and oxygen pressures at the reactor outlet are simultaneously at 0.5MPa, enabling rapid activation within 2 hours. Figure 2 As shown.

[0023] Activation procedure:

[0024] Step (1) Introduce 25°C deionized water to both the hydrogen and oxygen sides of the electrolytic reactor at a flow rate of 2 mL / min. -1 ·cm -2 Continue for 10 minutes to fully wet the electrolytic reactor electrodes.

[0025] Step (2): Then, a constant voltage strategy is used to activate the electrolytic reactor, controlling the average single cell voltage of the electrolytic reactor to 1.85V. At this time, the highest single cell voltage of the electrolytic reactor is 1.87V, the outlet water temperature is 25℃, and the outlet hydrogen and oxygen pressures of the electrolytic reactor are adjusted to 0.5MPa and maintained for 10 minutes.

[0026] In step (3), with an average single-cell voltage of 1.85V, the outlet water temperature of the electrolytic reactor will gradually increase as the operating time increases, and the current density will continue to increase. The outlet hydrogen and oxygen pressure will be maintained at 0.5MPa for 1 hour.

[0027] Step (4) After the outlet water temperature of the electrolytic reactor rises to the specified operating temperature of 60°C and stabilizes for 30 minutes, the average single-cell voltage change rate of the electrolytic reactor is 2mV / min, and the activation operation is completed.

[0028] Polarization curves of the electrolytic reactor were tested when the activation times were 1 hour, 2 hours, and 3 hours, respectively.

[0029] Example 2

[0030] This technical solution is adopted, but the operating conditions are not optimal. Activation is performed with the single-cell voltage of the electrolytic reactor constant at 1.65V, and the hydrogen and oxygen pressures at the reactor outlet are simultaneously at atmospheric pressure. Activation can be achieved in 3 hours. Figure 2 As shown.

[0031] Step (1): Introduce 25°C deionized water to both the hydrogen and oxygen sides of the electrolytic reactor at a flow rate of 2 mL / min. -1 ·cm -2 Continue for 10 minutes to fully wet the electrolytic reactor electrodes.

[0032] Step (2): Then, a constant voltage strategy is used to activate the electrolytic reactor, controlling the average single cell voltage of the electrolytic reactor to 1.65V. At this time, the highest single cell voltage of the electrolytic reactor is 1.66V, the outlet water temperature is 25℃, and the outlet hydrogen and oxygen pressure of the electrolytic reactor are adjusted to be at atmospheric pressure and maintained for 10 minutes.

[0033] Step (3): With the average single-cell voltage set at 1.65V, as the operating time increases, the outlet water temperature of the electrolytic reactor will gradually rise, the current density will continue to increase, and the outlet hydrogen and oxygen pressure will be maintained at atmospheric pressure for 1 hour.

[0034] Step (4): After the outlet water temperature of the electrolytic reactor rises to the specified operating temperature of 60°C and stabilizes for 30 minutes, the average single-cell voltage change rate of the electrolytic reactor is 2mV / min, and the activation operation is completed.

[0035] Polarization curves of the electrolytic reactor were tested when the activation times were 1 hour, 2 hours, 3 hours, and 5 hours, respectively.

[0036] Comparative Example 1

[0037] The electrolytic reactor was activated using a constant current method. After 5 hours of activation, the performance was still unstable, and the electrolytic reactor was not yet fully activated. Figure 4 As shown.

[0038] Activation procedure:

[0039] 1. Introduce 25°C deionized water to both the hydrogen and oxygen sides of the electrolytic reactor at a flow rate of 2 mL / min. -1 ·cm -2 Continue for 10 minutes to fully wet the electrolytic reactor electrodes.

[0040] 2. Subsequently, a constant current strategy was adopted for the electrolytic reactor activation operation, controlling the electrolytic reactor current density to 500 mA / cm². 2 At this time, the outlet water temperature of the electrolytic reactor was 26℃.

[0041] 3. Once the outlet water temperature of the electrolytic reactor rises to the designated operating temperature of 60℃ and stabilizes for 30 minutes, and the average single-cell voltage change rate of the electrolytic reactor is 2mV / min, the activation operation is complete.

[0042] The polarization curves of the electrolytic reactor were tested when the activation times were 1 hour, 2 hours, 3 hours, 5 hours and 7 hours respectively.

[0043] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method of accelerating the speed of activation of an electrolysis stack, characterized in that Comprising: S1: Deionized water is introduced to both the hydrogen and oxygen sides of the electrolytic reactor, and the temperature of the deionized water is controlled at... T 0. Keep the electrodes of the electrolytic reactor fully wet; S2: electrolytic stack activation operation is carried out by adopting constant voltage strategy, and the average single cell of the electrolytic stack is controlled to be V 1. T 1, the hydrogen pressure and the oxygen pressure at the electrolytic stack outlet are adjusted to be P 1 and P 2 respectively; wherein the voltage V 1 of the average single cell of the electrolytic stack ranges from 1.7 to 1.9 V; S3: In the average single cell set V 1, with the increase of running time, the outlet water temperature of electrolytic stack gradually rises, the current density continues to increase, and the outlet hydrogen pressure and oxygen pressure are maintained at P 1 and P 2, P 1 and P 2 range between 0.2 to 1 MPa; S4: The water temperature at the outlet of the electrolysis stack rises to the specified operating temperature T end for a period of time until the average single-cell voltage of the electrolysis stack does not change significantly, completing the activation operation; wherein the change value of the average single-cell voltage of the electrolysis stack is not higher than 5 mV / min; wherein the temperature of the deionized water is T 0 not more than 40°C, controlled T 1, T end not less than T 0, and not more than 90°C.

2. A method of accelerating the activation rate of an electrolysis stack according to claim 1, characterized in that: S1 Water flow range 0.5 to 5 mL min calculated as single electrolytic cell pool active area -1 · cm -2 with water retention time 3 to 30 minutes.

3. A method of accelerating the activation rate of an electrolysis stack according to claim 1, characterized in that: S2 maximum single cell voltage limit V max not more than 1.95 V.

4. The method of accelerating the activation of an electrolysis stack according to claim 1, characterized in that: The hydrogen pressure and the oxygen pressure at the outlet of the electrolysis stack in S3 are respectively in the range of P 1, P 2, wherein the range is between 0.2 and 1 MPa and the holding time is between 3 and 30 minutes.

5. The method of accelerating the activation of an electrolysis stack according to claim 1, characterized in that: In S4 the electrolysis stack to be operated is operated in a specified operating temperature range of 50 to 90°C. In S4 the electrolysis stack to be operated is operated in

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