Method for detecting adsorption capacity of hydrogen adsorbent

Abstract

The invention discloses a method for detecting the adsorption capacity of a hydrogen adsorbent. The method comprises the following steps: S1, preparing equipment; s2, placing the adsorbent to be tested on an electronic balance, recording the mass of the adsorbent weighed by the electronic balance at the moment and recording the mass as g1; s3, after the vacuum degree in the test bin is higher than the vacuum degree to be measured and is stabilized, closing the valve and the regulating valve I; s4, opening the hydrogen cylinder, and controlling to open and finely adjust the regulating valve I, so that the vacuum degree in the test bin is always maintained at the set vacuum degree to be measured; s5, when the reading of the electronic balance is stable and unchanged and the reading of the mass flow meter is zero, the controller controls to close the regulating valve I, adsorption quantity measurement under the set vacuum degree is ended, the mass of the adsorbent weighed by the electronic balance at the moment is recorded and recorded as g2, and the accumulated flow of the mass flow meter is recorded; g2-g1 is the hydrogen absorption amount of the adsorbent under the vacuum degree. The device has the advantage of being capable of measuring the adsorption capacity of the hydrogen adsorbent under the specific equilibrium pressure.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen adsorbents, and in particular to a method for detecting the adsorption capacity of a hydrogen adsorbent. Background Art

[0002] The current common hydrogen adsorbent test method uses the equilibrium pressure measurement principle to fill different amounts of hydrogen into the test space, and the vacuum degree after the adsorbent adsorption pressure is balanced is used as the equilibrium pressure, and the amount of hydrogen reduced at this equilibrium pressure acts as the adsorption amount. The equilibrium pressure measured by this test method is completely random, and it is impossible to measure the adsorption amount of the adsorbent at the set vacuum degree, which has great limitations. Due to the randomness of the test data, for high vacuum operations, the calculation of hydrogen absorption in the vacuum layer cannot be accurate, affecting the safety of hydrogen use. Summary of the invention

[0003] The object of the present invention is to provide a method for detecting the adsorption capacity of a hydrogen adsorbent, which can measure the amount of hydrogen adsorbent adsorbed at a specific equilibrium pressure.

[0004] To achieve the above object, the present invention adopts the following technical solution: a method for detecting the adsorption capacity of a hydrogen adsorbent, comprising the following steps: S1: Equipment preparation: The hydrogen adsorbent adsorption capacity detection device includes: a test chamber, a vacuum pump, a hydrogen bottle, a temperature control system, and a controller; the test chamber is composed of a lower base and an upper cover shell; the vacuum pump is connected to the interior of the test chamber through a vacuum pipeline, and a valve is arranged on the vacuum pipeline. The gas outlet end of the hydrogen bottle is connected to the interior of the test chamber through a hydrogen supply pipeline, and a regulating valve 1 and a mass flow meter are arranged on the hydrogen supply pipeline. The temperature control system is used to control the internal temperature of the test chamber, an electronic balance is installed inside the test chamber, and a temperature sensor for real-time monitoring of the internal temperature of the test chamber and a vacuum gauge for real-time monitoring of the vacuum degree inside the test chamber are arranged on the test chamber. The vacuum pump, valve, hydrogen bottle, regulating valve 1, mass flow meter, temperature control system, electronic balance, vacuum gauge, and temperature sensor are all electrically connected to the controller and controlled by the controller; S2: First, according to the test requirements, the controller adjusts the internal temperature of the test chamber to the set temperature through the temperature control system, then opens the test chamber cover, puts the adsorbent to be tested on the electronic balance, and records the mass of the adsorbent weighed by the electronic balance at this time and records it as g1; S3: Close the test chamber cover, the controller first controls the closing of the hydrogen cylinder, then controls the opening of the valve and the regulating valve 1, and then controls the opening of the vacuum pump, so that the vacuum pump uses the vacuum pipeline to evacuate the inside of the test chamber, until the vacuum degree inside the test chamber is higher than the vacuum degree to be measured and stabilizes, and then closes the valve and the regulating valve 1; S4: After the controller determines that the internal temperature of the test chamber has reached the set temperature and stabilized according to the temperature data fed back by the temperature sensor, the hydrogen cylinder is opened first, and then the regulating valve 1 is controlled to be opened and fine-tuned, so that the vacuum degree inside the test chamber is always maintained at the set vacuum degree to be measured; S5: The controller collects the readings of the electronic balance and the mass flow meter in real time. The reading of the electronic balance will gradually increase as the adsorbent absorbs hydrogen, and the reading of the mass flow meter will gradually decrease as the adsorbent is saturated with adsorption. When the reading of the electronic balance is stable and unchanged and the reading of the mass flow meter is zero, the controller controls the closing of the regulating valve 1 to end the adsorption measurement under the set vacuum degree, record the mass of the adsorbent weighed by the electronic balance at this time and record it as g2, and record the accumulated flow of the mass flow meter; g2-g1 is the amount of hydrogen absorbed by the adsorbent under this vacuum degree, and the relationship curve between the hydrogen absorption amount and time is synchronously recorded in the computer.

[0005] Furthermore, in the aforementioned method for detecting the adsorption capacity of a hydrogen adsorbent, in which: in S3, a vacuum pump uses a vacuum line to evacuate the interior of a test chamber until the vacuum degree inside the test chamber reaches a set requirement of two exponential levels higher than the vacuum degree to be measured and stabilizes, and then valve one and regulating valve one are closed.

[0006] Further, the above-mentioned method for detecting the adsorption capacity of a hydrogen adsorbent, wherein: in S5, after the adsorption amount measurement under a set vacuum degree is completed, if it is necessary to continue to measure the adsorption amount under other vacuum degrees, steps S3-S5 can be repeated, and the mass of the adsorbent after each adsorption is recorded as g3, g4, ... g n ; g n -g1 is the total hydrogen absorption of the adsorbent under the last vacuum degree, g x -g y That is, when the adsorption is saturated at vacuum degrees X and Y, the amount of hydrogen absorbed by the adsorbent in the vacuum range from vacuum degree X to vacuum degree Y; the total flow measured by the mass flowmeter can be verified with the adsorption mass to verify the correctness of the data.

[0007] Furthermore, in the aforementioned method for detecting the adsorption capacity of a hydrogen adsorbent, the base and the cover are connected and sealed by a high vacuum clamp.

[0008] Furthermore, in the aforementioned method for detecting the adsorption capacity of a hydrogen adsorbent, the temperature control system comprises a constant temperature box, the test chamber is placed inside the constant temperature box, and the control system of the constant temperature box is electrically connected to the controller.

[0009] Further, the aforementioned method for detecting the adsorption capacity of a hydrogen adsorbent, wherein: a temperature control system comprises: a heat exchange platform is installed at the bottom of the test chamber, the interior of the heat exchange platform is hollow to form a heat exchange shell, a shell inlet and a shell outlet are arranged on the heat exchange platform, the shell inlet is connected to a heat exchange medium liquid inlet pipe, the shell outlet is connected to a heat exchange medium liquid outlet pipe, a heat exchange tube is installed inside the heat exchange platform, the heat exchange tube constitutes a heat exchange tube pass, one end of the heat exchange tube is connected to a liquid nitrogen container outside the test chamber through a liquid inlet pipe, a regulating valve 2 is installed on the liquid inlet pipe, the other end of the heat exchange tube is connected to an exhaust pipe, and the exhaust pipe extends out of the test chamber; the liquid nitrogen container and the regulating valve 2 are both electrically connected to the controller.

[0010] Through the implementation of the above technical scheme, the beneficial effects of the present invention are: (1) a specific equilibrium pressure can be set, and the adsorption amount of the adsorbent under this equilibrium pressure can be automatically measured, with a high degree of automation and easy operation; (2) the adsorption curve under a specific equilibrium pressure can be measured and drawn, and the actual hydrogen absorption capacity and adsorption rate of the adsorbent in each vacuum section can be measured; (3) quantitative adjustment of the test temperature can be achieved, and the adjustment range is large. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The present invention is a schematic diagram of the structural principle of a device for detecting the adsorption capacity of a hydrogen adsorbent when a temperature control system is used.

[0012] Figure 2 This is a schematic diagram of the structural principle of a hydrogen adsorbent adsorption capacity detection device described in the present invention when another temperature control system is adopted. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0014] like Figure 1 , Figure 2 As shown, a method for detecting the adsorption capacity of a hydrogen adsorbent comprises the following steps: S1: Equipment preparation: The hydrogen adsorbent adsorption capacity detection device includes: a test chamber 1, a vacuum pump 3, a hydrogen bottle 6, a temperature control system, and a controller 100; the test chamber 1 is composed of a lower base and an upper cover; the vacuum pump 3 is connected to the inside of the test chamber 1 through a vacuum pumping line 2, and a valve 4 is arranged on the vacuum pumping line 3; the gas outlet end of the hydrogen bottle 6 is connected to the inside of the test chamber 1 through a hydrogen supply line 5, and a regulating valve 7 and a mass flow meter 8 are arranged on the hydrogen supply line 5; the temperature control system is used to control the internal temperature of the test chamber, and an electronic The test chamber 1 is provided with a temperature sensor 11 for real-time monitoring of the temperature inside the test chamber, and a vacuum gauge 12 for real-time monitoring of the vacuum degree inside the test chamber. The vacuum pump 3, valve 4, hydrogen cylinder 6, regulating valve 7, mass flow meter 8, temperature control system, electronic balance 10, vacuum gauge 12, and temperature sensor 11 are all electrically connected to the controller 100 and controlled by the controller 100; the vacuum gauge 12, temperature sensor 11 and electronic balance 10 can feed back the relevant vacuum, temperature and weight data collected in real time to the controller 100 in real time; S2: First, according to the test requirements, the controller adjusts the internal temperature of the test chamber to the set temperature through the temperature control system, then opens the test chamber cover, puts the adsorbent to be tested on the electronic balance 10, and records the mass of the adsorbent weighed by the electronic balance 10 at this time and records it as g1; S3: The test chamber cover is closed, and the controller 100 first controls the closing of the hydrogen cylinder 6, and then controls the opening of the valve 4 and the regulating valve 7, and then controls the opening of the vacuum pump 3. At this time, the vacuum pump 3 uses the vacuum line 2 to evacuate the inside of the test chamber 1. While the vacuum pump 3 evacuates the inside of the test chamber, it also evacuates the hydrogen supply line 5, so as to exhaust the impurity gas in the vacuum line 2, the inside of the test chamber, and the hydrogen supply line 5 as much as possible, thereby reducing the interference of the impurity gas on the adsorption capacity test of the adsorbent, thereby improving the accuracy of the adsorption capacity test of the adsorbent; until the vacuum degree inside the test chamber reaches the setting requirement of two index levels higher than the vacuum degree to be measured and stabilizes, the valve 4 and the regulating valve 7 are closed; In this test method, step S3 is important and necessary. Before the hydrogen cylinder is opened to supply hydrogen, the vacuum degree inside the test chamber is first adjusted to be higher than the vacuum degree to be measured. On the one hand, by vacuuming, the impurity gases in the vacuuming pipeline 2, the inside of the test chamber, and the hydrogen supply pipeline 5 can be exhausted as much as possible, reducing the interference of the impurity gases on the adsorption capacity test of the adsorbent, thereby improving the accuracy of the adsorption capacity test of the adsorbent; on the other hand, since the vacuum degree inside the test chamber will inevitably decrease after the hydrogen cylinder is supplied with hydrogen, the vacuum degree inside the test chamber is first adjusted to be higher than the vacuum degree to be measured. Vacuum degree, so that after the hydrogen cylinder supplies hydrogen, the vacuum degree inside the test chamber 1 can be gradually reduced and reach and always maintain the set vacuum degree to be measured, thereby ensuring that the adsorption amount of the adsorbent under the set equilibrium pressure can be accurately measured; if the vacuum degree inside the test chamber has reached the vacuum degree to be measured before the hydrogen cylinder supplies hydrogen, then after the hydrogen cylinder supplies hydrogen, the vacuum degree inside the test chamber will inevitably be lower than the vacuum degree to be measured due to the addition of hydrogen, resulting in the vacuum degree in the test chamber being unable to reach and maintain the vacuum degree to be measured, and inevitably causing inaccurate test results; S4: After the controller 100 determines that the internal temperature of the test chamber 1 has reached the set temperature and stabilized according to the temperature data fed back by the temperature sensor 11, the hydrogen bottle 6 is opened first, and then the regulating valve 1 7 is controlled to be opened and fine-tuned, so that the vacuum degree inside the test chamber 1 is always maintained at the set vacuum degree to be measured; S5: The controller 100 collects the readings of the electronic balance and the mass flow meter in real time. The reading of the electronic balance 10 will gradually increase as the adsorbent absorbs hydrogen, and the reading of the mass flow meter will gradually decrease as the adsorbent is saturated with adsorption. When the reading of the electronic balance 10 is stable and unchanged and the reading of the mass flow meter 8 is zero, the controller 100 controls the closing of the regulating valve 7 to end the adsorption measurement under the set vacuum degree, record the mass of the adsorbent weighed by the electronic balance at this time and record it as g2, and record the accumulated flow of the mass flow meter 8; g2-g1 is the amount of hydrogen absorbed by the adsorbent under this vacuum degree, and the relationship curve between the amount of hydrogen absorbed and time is synchronously recorded in the computer; After the adsorption amount measurement under the set vacuum degree is completed, if it is necessary to continue to measure the adsorption amount under other vacuum degrees, steps S3-S5 can be repeated; the mass of the adsorbent after each adsorption is recorded as g3, g4, ... g n ; g n -g1 is the total hydrogen absorption of the adsorbent under the last vacuum degree, g x -g y That is, when the adsorption is saturated at vacuum degrees X and Y, the amount of hydrogen absorbed by the adsorbent in the vacuum range from vacuum degree X to vacuum degree Y; the total flow measured by the mass flowmeter can be verified with the adsorption mass to verify the correctness of the data.

[0015] In actual testing, there are many types of temperature control system structures. The following describes the structures of two temperature control systems. Figure 1 As shown, the structure of one of the temperature control systems includes: a constant temperature box 9, a test chamber 1 is placed inside the constant temperature box 9, and a control system 91 of the constant temperature box 9 is electrically connected to a controller 100 and controlled by the controller; when the temperature inside the test chamber is constant, the controller 100 adjusts the temperature of the constant temperature box 9 to a preset temperature required for the test chamber test by controlling the constant temperature box control system 91. At this time, the constant temperature box 9 will heat the test chamber located inside it, and adjust and maintain the temperature inside the test chamber 1 at the preset temperature required for the test chamber test. At the same time, the controller 100 will determine whether the real-time temperature inside the test chamber is maintained at the preset temperature required for the test based on the temperature data fed back in real time by the temperature sensor 11. Only after the real-time temperature inside the test chamber reaches and stabilizes at the preset temperature required for the test, the hydrogen adsorbent adsorption capacity test will be performed.

[0016] like Figure 2 As shown, the structure of another temperature control system includes: a heat exchange platform 13 is installed at the bottom of the test chamber 1, the interior of the heat exchange platform 13 is hollow to form a heat exchange shell, a shell inlet and a shell outlet are arranged on the heat exchange platform 13, the shell inlet is connected to the heat exchange medium liquid inlet pipe 14, and the shell outlet is connected to the heat exchange medium liquid outlet pipe 15, a heat exchange tube 16 is installed inside the heat exchange platform 13, the heat exchange tube 16 constitutes a heat exchange tube, one end of the heat exchange tube 16 is connected to the liquid nitrogen container 18 outside the test chamber 1 through the liquid inlet pipe 17, a regulating valve 19 is installed on the liquid inlet pipe 17, and the other end of the heat exchange tube 16 is connected to the exhaust pipe 20, and the exhaust pipe 20 extends out of the test chamber 1; the liquid nitrogen container 18 and the regulating valve 19 are both electrically connected to the controller 100 and controlled by the controller; When the inside of the test chamber is heat exchanged and kept at a constant temperature, the heat exchange medium can be selected according to the required temperature (water, ethylene glycol, R12, etc.). The heat exchange medium is a hot medium, and the heat exchange medium is passed from the heat exchange medium liquid inlet pipe 14 into the heat exchange shell of the heat exchange platform 13. At the same time, the controller 100 will control the opening of the liquid nitrogen container 18 and the regulating valve 19, so that the liquid nitrogen in the liquid nitrogen container 18 passes through the heat exchange tube formed by the heat exchange tube 16 inside the heat exchange platform along the liquid inlet pipe 17. In the process of the liquid nitrogen passing through the heat exchange tube, it will exchange heat with the heat exchange medium in the heat exchange shell. In the heat exchange process, the controller 100 will The temperature data fed back by the temperature sensor 11 in real time is used to adjust the flow rate of liquid nitrogen by controlling the regulating valve 19, thereby adjusting the temperature of the heat exchange medium in the heat exchange platform in real time, and then adjusting the internal temperature of the test chamber heated by the heat exchange platform, until the temperature inside the test chamber 1 is adjusted and maintained at the preset temperature. Only after the temperature inside the test chamber reaches and stabilizes at the preset temperature required for the test, the adsorption capacity of the hydrogen adsorbent will be tested; the theoretical temperature range of the heat exchange platform in this embodiment can reach -180 to 100°C, which can meet the test requirements of various temperature conditions, and its functionality far exceeds that of a constant temperature box.

[0017] The advantages of the present invention are: (1) a specific equilibrium pressure can be set, and the adsorption amount of the adsorbent under the equilibrium pressure can be automatically measured, with a high degree of automation and easy operation; (2) the adsorption curve under a specific equilibrium pressure can be measured and drawn, and the actual hydrogen absorption capacity and adsorption rate of the adsorbent in each vacuum section can be measured; (3) quantitative adjustment of the test temperature can be achieved, and the adjustment range is large.

[0018] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent change made according to the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. A method for detecting the adsorption capacity of a hydrogen adsorbent, characterized in that: The following steps are involved: S1: Equipment preparation: The hydrogen adsorbent adsorption capacity detection device includes: a test chamber, a vacuum pump, a hydrogen bottle, a temperature control system, and a controller; the test chamber is composed of a lower base and an upper cover shell; the vacuum pump is connected to the interior of the test chamber through a vacuum pipeline, and a valve is arranged on the vacuum pipeline. The gas outlet end of the hydrogen bottle is connected to the interior of the test chamber through a hydrogen supply pipeline, and a regulating valve 1 and a mass flow meter are arranged on the hydrogen supply pipeline. The temperature control system is used to control the internal temperature of the test chamber, an electronic balance is installed inside the test chamber, and a temperature sensor for real-time monitoring of the internal temperature of the test chamber and a vacuum gauge for real-time monitoring of the vacuum degree inside the test chamber are arranged on the test chamber. The vacuum pump, valve, hydrogen bottle, regulating valve 1, mass flow meter, temperature control system, electronic balance, vacuum gauge, and temperature sensor are all electrically connected to the controller and controlled by the controller; S2: First, according to the test requirements, the controller adjusts the internal temperature of the test chamber to the set temperature through the temperature control system, then opens the test chamber cover, puts the adsorbent to be tested on the electronic balance, and records the mass of the adsorbent weighed by the electronic balance at this time and records it as g1; S3: Close the test chamber cover, the controller first controls the closing of the hydrogen cylinder, then controls the opening of the valve and the regulating valve 1, and then controls the opening of the vacuum pump, so that the vacuum pump uses the vacuum pipeline to evacuate the inside of the test chamber, until the vacuum degree inside the test chamber is higher than the vacuum degree to be measured and stabilizes, and then closes the valve and the regulating valve 1; S4: After the controller determines that the internal temperature of the test chamber has reached the set temperature and stabilized according to the temperature data fed back by the temperature sensor, the hydrogen cylinder is opened first, and then the regulating valve 1 is controlled to be opened and fine-tuned, so that the vacuum degree inside the test chamber is always maintained at the set vacuum degree to be measured; S5: The controller collects the readings of the electronic balance and the mass flow meter in real time. The reading of the electronic balance will gradually increase as the adsorbent absorbs hydrogen, and the reading of the mass flow meter will gradually decrease as the adsorbent is saturated with adsorption. When the reading of the electronic balance is stable and unchanged and the reading of the mass flow meter is zero, the controller controls the closing of the regulating valve 1 to end the adsorption measurement under the set vacuum degree, record the mass of the adsorbent weighed by the electronic balance at this time and record it as g2, and record the accumulated flow of the mass flow meter; g2-g1 is the amount of hydrogen absorbed by the adsorbent under this vacuum degree.

2. A method for detecting the adsorption capacity of a hydrogen adsorbent according to claim 1, characterized in that: In S3, the vacuum pump uses the vacuum pipeline to evacuate the inside of the test chamber until the vacuum degree inside the test chamber reaches the set requirement of two index levels higher than the vacuum degree to be measured and stabilizes, and then closes valve 1 and regulating valve 1.

3. A method for detecting the adsorption capacity of a hydrogen adsorbent according to claim 1, characterized in that: After completing the measurement of the adsorption amount under the set vacuum degree, if it is necessary to continue to measure the adsorption amount under other vacuum degrees, steps S3-S5 can be repeated, and the mass of the adsorbent after each adsorption is recorded as g3, g4, ... g n ; g n -g1 is the total hydrogen absorption of the adsorbent under the last vacuum degree, g x -g y That is, when the adsorption is saturated at vacuum degrees X and Y, the amount of hydrogen absorbed by the adsorbent in the vacuum range from vacuum degree X to vacuum degree Y; the total flow measured by the mass flowmeter can be verified with the adsorption mass to verify the correctness of the data.

4. A method for detecting the adsorption capacity of a hydrogen adsorbent according to claim 1, characterized in that: The base and the cover shell are connected and sealed by a high vacuum clamp.

5. A method for detecting the adsorption capacity of a hydrogen adsorbent according to claim 1, 2, 3 or 4, characterized in that: The temperature control system comprises: a constant temperature box, the test chamber is arranged inside the constant temperature box, and the control system of the constant temperature box is electrically connected to the controller.

6. A method for detecting the adsorption capacity of a hydrogen adsorbent according to claim 1, 2, 3 or 4, characterized in that: The temperature control system includes: a heat exchange platform is installed at the bottom of the test chamber, the interior of the heat exchange platform is hollow to form a heat exchange shell, a shell inlet and a shell outlet are arranged on the heat exchange platform, the shell inlet is connected to a heat exchange medium liquid inlet pipe, the shell outlet is connected to a heat exchange medium liquid outlet pipe, a heat exchange tube is installed inside the heat exchange platform, the heat exchange tube constitutes a heat exchange tube, one end of the heat exchange tube is connected to a liquid nitrogen container outside the test chamber through a liquid inlet pipe, a regulating valve 2 is installed on the liquid inlet pipe, the other end of the heat exchange tube is connected to an exhaust pipe, and the exhaust pipe extends out of the test chamber; the liquid nitrogen container and the regulating valve 2 are both electrically connected to the controller.

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