Dissolution test method for soluble metal

Abstract

The invention relates to a dissolution testing method for soluble metal, and in the whole period of sample dissolution testing, dissolution products are separated and quantitatively recorded, and then dissolution rate is obtained, fed back in time and completely recorded. According to the invention, the dissolution condition and rate of the material can be recorded in real time, and the obtained dissolution rate data is real and accurate; in the dissolution testing process, the device is completely automatic, simple to operate, timely and accurate.

Description

Technical Field

[0001] This application relates to a method for testing the dissolution of soluble metals. Background Technology

[0002] Current systems for evaluating the solubility of soluble materials involve placing the sample in an electrolyte solution at an appropriate temperature, removing it after a certain time, drying it, weighing it, and using the change in weight to measure the solubility of the material and characterize its dissolution rate. This method has many drawbacks: (1) During the material dissolution process, the dissolution status and rate of the material cannot be recorded in real time. This is because the dissolution rate of the material is usually irregular, and when calculating the dissolution rate, it can only be assumed to be a regular shape. The actual dissolution rate has an unavoidable error with it; (2) When taking out the sample, drying and weighing the process must interrupt the dissolution process, which cannot accurately and timely reflect the actual dissolution status. The interruption process will inevitably damage the material and the dissolution medium, resulting in a difference between the test results and the actual application parameters; (3) In the fixed container, the concentration of the electrolyte solution will decrease over time, and the water will evaporate, which cannot accurately reflect the dissolution rate at a certain concentration; (4) When drying and weighing the sample every once in a while, the surface dissolution products and the porosity of the material itself will cause additional material loss. The weight loss data and test conclusions are seriously inaccurate, and human factors far exceed the system error; (5) During underground construction, the liquid will flow and the pressure will change. Existing test devices cannot accurately simulate the underground conditions; (6) In particular, the electrolyte solution is basically a water-based solution with a boiling point of about 100°C. Current test methods cannot test the dissolution rate above 100°C of the boiling point of the aqueous solution of the dissolution medium. Summary of the Invention

[0003] The purpose of this application is to provide a method for testing the dissolution of soluble metals. During the material dissolution process, the dissolution status and rate can be recorded in real time, and the obtained dissolution rate data is true and accurate. During the dissolution test, only the amount of products generated by the dissolution reaction needs to be measured. The operation is simple and accurate, which can greatly expand the selection space of test items and simulate the application scenarios of soluble metal materials to the greatest extent. The amount of products generated by the dissolution reaction can be obtained by measuring any one or more combinations of the generated gas flow rate, electrochemical potential of a certain component of the solution, spectral data, selective electrode potential parameters, and pressure parameters.

[0004] This application relates to a method for testing the dissolution of soluble metals, which involves continuous real-time testing of soluble metal materials in different dissolution media, ranging from below the boiling point of the dissolution media at atmospheric pressure to well above the boiling point of the dissolution media at atmospheric pressure. The method specifically includes the following steps: By utilizing the difference in saturated vapor pressure of a solution at different temperatures, different pressures are applied to the dissolving medium to adjust its boiling point temperature, thereby causing the dissolution reaction to occur at a boiling point of the dissolving medium below or above the boiling point of the dissolving medium at atmospheric pressure; the dissolving medium can be an aqueous dispersion or a non-aqueous dispersion. The dissolution test is conducted continuously and without interruption within a closed reaction unit using online detection. The testing device comprehensively simulates the dissolution process, and measures and provides feedback on the dissolution rate in real time. The increase or decrease in the amount of dissolved products causes changes in the pressure, flow rate, concentration, ionic electrochemical characteristics, phase spectral characteristics, and pH-ORP characteristics of the test device system. The real-time change in the amount of dissolved products is obtained by testing at least one of the above parameters through the test device. The dissolution rate of the metal dissolution reaction is calculated using the obtained real-time amount of dissolved products. The dissolution rate value is directly output through data processing.

[0005] In this method, when the required test temperature is higher than the boiling point of the dissolving medium, the pressure inside the dissolving reaction unit is increased to make the boiling point of the dissolving medium greater than or equal to the required test temperature, and the dissolving medium is heated to the required test temperature for dissolution rate testing. The equipment test parameters are selected and adjusted by using the boiling point and saturated vapor pressure of the dispersed solution to adjust the test temperature or pressure. The dissolution rate is characterized by the formation rate of the dissolved products, which are at least one of gas, liquid, and solid. The method involves separating the dissolved products, quantitatively testing one or more products with specific performance characteristics online according to their properties, and simultaneously processing the data to obtain the dissolution reaction rate.

[0006] The testing device includes a dissolution reaction unit, which is connected to a dissolution medium storage unit and a dissolution product detection unit. The dissolution medium storage unit is connected to the dissolution reaction unit via a circulation unit. The dissolution product detection unit is used to detect the amount of products generated in the dissolution reaction unit. The pressure inside the dissolution reaction unit ensures that the boiling point of the dissolution medium at that pressure is greater than or equal to the required test temperature. The internal pressure of the dissolution reaction unit is controlled between 0.1 and 4 MPa by a pressure control device, maintaining the dissolution medium inside the dissolution reaction unit above its atmospheric boiling point.

[0007] Specifically, when the required test temperature is lower than the boiling point of the dissolved medium, the pressure control device controls the pressure inside the dissolution reaction unit at 1 atmosphere; when the required test temperature is higher than the boiling point of the dissolved medium, the pressure control device increases the pressure inside the dissolution reaction unit so that the boiling point of the dissolved medium is greater than or equal to the required test temperature, thereby maintaining the test temperature.

[0008] The testing device further includes a control unit, which comprises a controller, a human-machine interface device, and a control module. The control module includes a multi-loop PID temperature control unit, a pressure monitoring and interlock control unit, a concentration detection, a liquid level monitoring and interlock control unit, and a safety interlock protection unit. The safety interlock protection unit includes at least one of a pressure alarm module, a temperature alarm module, a liquid level over-limit module, and a gas leak alarm module.

[0009] This also includes the following steps: (1) Inject the concentrated dissolving medium and dispersant into the storage tank according to the concentration to reach the required concentration of dissolving medium; turn on the liquid level detection and concentration detection module, remove impurities through the filter and pump into the circulation power unit; (2) Set the target temperature and start the heating device. The temperature control system uses the real-time data fed back by the temperature sensor to control the heating power using the adjustment algorithm, so that the temperature of the medium solution gradually rises to the set value and stabilizes. The system pressure stabilizes in the range of 0.1-4MPa after the temperature rises to the target temperature. The pressure sensor feeds back the data in real time. When the pressure exceeds 4.1 MPa, the unloading valve automatically opens to release pressure to 4MPa. If the pressure exceeds 4.5MPa, the system issues an audible and visual alarm and starts the emergency shutdown procedure. After the delivery pump heats the medium solution to the set temperature, it enters the reactor of the dissolution reaction unit. (3) The medium solution after temperature adjustment enters the reactor and comes into full contact with the sample to be tested in the reactor to carry out a continuous dissolution reaction; the pressure sensors of the reactor monitor the pressure in the chamber to ensure stable operating pressure; (4) The mixture of gas and water vapor generated by the reaction enters the dehydration and drying device through the outlet pipeline to remove water vapor, so that the water vapor content at the outlet is ≤5% RH; the dehydrated gas enters the gas pressure detection unit, the flow meter records the gas volume, and the control system automatically calculates the gas emission molar amount and generation rate through the ideal gas state equation. The data is displayed and stored in real time; other gases or compounds generated by the reaction enter the test unit through one or more methods selected from filtration, separation, membrane treatment, and molecular sieve treatment. (5) The test unit includes online measurement methods selected from flow rate, pressure, selective electrode, electrode potential, spectrum, and pH value to quantitatively detect, measure, and record the formation rate of dissolved products; (6) The reaction medium solution is returned to the main storage tank through the pipeline to form a closed loop; the detected gas enters the compressor, is compressed and stored in the collection tank.

[0010] Preferably, in step (5), the selection of the measurement method is based on the combination of the products and concentration changes of the dissolution reaction of the specific system to be tested; When a gas is generated from the dissolution reaction products, and the change in the amount of a single gas generated can determine the reaction rate, the reaction rate is identified by the measurement data of the pressure and flow rate of the single gas. If the change in the amount of a single gas generated is insufficient to fully identify the dissolution reaction rate, the pH value of the products before and after the reaction is measured, or the redox potential of a certain substance before and after the reaction is tested, or ion-selective electrode testing is performed based on the ion concentration characteristics, or spectral analysis is performed based on the spectral changes of a certain substance before and after the reaction, or a combination of at least two of the above methods is used. When no gas is produced in the dissolution reaction, and only the liquid and solid phases change, the dissolution reaction rate is characterized by at least one of the changes in pH value, redox potential, selective ion characteristic potential, or characteristic spectral data of the products before and after the dissolution reaction.

[0011] The pressure inside the dissolution reaction unit of this application can be controlled from 1 standard atmosphere to 4 MPa, allowing the temperature of the dissolving medium to be controlled within any set value ranging from room temperature to 250°C. The amount of dissolved product is measured accurately and in real time in the reaction product detection unit, so the dissolution rate value is also output and recorded accurately, timely, and continuously. In particular, for water-based dissolution media, the dissolution rate of soluble materials can be accurately measured in real time at any set temperature between 100-250°C above the conventional boiling point. Throughout the entire sample dissolution test cycle, the dissolved products are separated, quantitatively recorded, and the dissolution rate is obtained, with timely feedback and complete recording. The dissolution reaction is continuous and uninterrupted throughout the entire test process, without the need to terminate the dissolution process midway, remove the sample for weighing to confirm weight loss. This invention can record the dissolution status and rate of materials in real time, and the obtained dissolution rate data is true and accurate; during the dissolution test, the device is fully automatic, simple to operate, and timely and accurate. Attached Figure Description

[0012] Figure 1 This is the reaction data curve from Example 1 of this application.

[0013] Figure 2 This is the reaction data curve in Example 2 of this application.

[0014] Figure 3 This is the reaction data curve in Example 3 of this application. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be arbitrarily combined with each other.

[0016] This application relates to a method for testing the dissolution of soluble metals, which involves continuous real-time testing of soluble metal materials in different dissolution media, ranging from below the boiling point of the dissolution media at atmospheric pressure to well above the boiling point of the dissolution media at atmospheric pressure. Specifically, the method includes: By utilizing the difference in saturated vapor pressure of a solution at different temperatures, varying pressures are applied to the dissolving medium to adjust its boiling point temperature, thereby causing the dissolution reaction to occur at or above the boiling point of the dissolving medium at atmospheric pressure. The dissolving medium can be a water-based or non-water-based dispersion. For water-based dissolving media, the dissolution rate of the sample is tested above 100°C. For water-based dispersion solutions, the dissolution reaction rate is tested over a temperature range from room temperature to 250°C. For non-water-based dissolving media, the dissolution rate of the sample can be tested above the boiling point of the dissolving medium at atmospheric pressure. Temperatures above the boiling point of the dissolving medium are obtained by increasing the pressure of the dissolving medium system to reach or exceed the saturated vapor pressure at the corresponding temperature. Water has a saturated vapor pressure of 3.97 MPa at 250°C. Specifically, if the system pressure is increased to 3.97 MPa, the solution will only boil at 250°C, and the test will be conducted at any temperature below the boiling point. The dissolution test is conducted continuously and without interruption within a closed reaction unit using online detection. The testing device comprehensively simulates the dissolution process, and measures and provides feedback on the dissolution rate in real time. The increase or decrease in the amount of dissolved products causes changes in the pressure, flow rate, concentration, ionic electrochemical characteristics, phase spectral characteristics, and pH-ORP characteristics of the test device system. The real-time change in the amount of dissolved products is obtained by testing at least one of the above parameters through the test device. The dissolution rate of the metal dissolution reaction is calculated using the obtained real-time amount of dissolved products. The dissolution rate value is directly output through data processing.

[0017] The testing apparatus of this application includes a dissolution reaction unit, which is connected to a dissolution medium storage unit and a dissolution product testing unit. The dissolution reaction testing unit includes testing modules selected from one or more combinations of pressure, flow rate, concentration, ionic electrochemical characteristics, phase spectral characteristics, and pH-ORP. The dissolution medium storage unit is connected to the dissolution reaction unit through a circulation unit. The dissolution product testing unit is equipped with separation, membrane treatment, molecular sieve treatment, drying, and flow metering devices. The pressure inside the dissolution reaction unit is controlled at 0.1-4.0 MPa, so that the boiling point of the dissolution medium is maintained in a wide temperature range up to 250°C.

[0018] The device may include a drying device between the dissolved product measuring device and the dissolved reaction unit; the dissolved product measuring device may also be connected to a gas compressor and a gas storage tank; at least one of the dissolved product measuring device and the gas storage tank may be connected to a gas leak detection device; the dissolved product measuring device may also include a test module selected from one or more combinations of pressure, flow rate, concentration, ion electrochemical characteristics, phase spectral characteristics, and pH-ORP; the dissolved reaction unit may also be connected to at least one of a temperature monitoring device, a liquid level monitoring device, and a heating device; the dissolved medium storage unit may include at least one of a liquid level monitoring device, a pressure gauge, and a concentration monitoring device; the dissolved reaction unit may include at least two reactors connected in parallel; it may also include a control unit, which may include a controller, a human-machine interface device, and a control module; the control module may include a multi-loop PID temperature control unit, a pressure monitoring and interlock control unit, a liquid level monitoring and interlock control unit, and a safety interlock protection unit; the safety interlock protection unit may include at least one of a pressure alarm module, a temperature alarm module, a liquid level over-limit module, and a gas leak alarm module.

[0019] This application also relates to a method for testing the dissolution of soluble metallic materials, including the following steps: (1) Supply of dissolving medium For soluble magnesium alloys, the dissolving medium is an electrolyte solution containing chloride ions. This is also the main electrolyte component of oil well fluids, typically equivalent to a potassium chloride concentration of 0.1-3.5% under normal downhole conditions. The main storage tank of this device injects a chloride salt solution with a mass concentration of 3%-6% as the base fluid. Once the liquid level reaches the preset height, the liquid level monitoring and concentration detection module is activated, and the fluid enters the circulating power unit after impurities are removed by a filter. (2) Continuous replacement The circulating power unit starts the delivery pump and adjusts the circulation flow through the valve. The salt solution enters the heating device through the check valve. The flow detection element collects the flow data in real time and feeds it back to the control system for coordinated adjustment to ensure the stability of the total flow. (3) Temperature and pressure regulation A target temperature is set between room temperature and 250℃. The heating device is started, and the temperature control system uses an adjustment algorithm to control the heating power based on real-time data from the temperature sensor, so that the temperature of the salt solution gradually rises to the set value and stabilizes, with temperature fluctuations controlled within ±1℃. After the system temperature rises to the target temperature, it stabilizes in the range of 3.5-4.0MPa. The pressure sensor provides real-time feedback data. When the pressure exceeds 4.1MPa, the unloading valve automatically opens to release pressure to 4.0MPa. If the pressure exceeds 4.5MPa, the system issues an audible and visual alarm and initiates an emergency shutdown procedure. After the transfer pump heats the salt solution to the set temperature, it enters the reactor of the dissolution reaction unit. (4) Dissolution reaction The temperature-controlled salt solution enters the reactor and comes into full contact with the sample to be tested inside the reactor to carry out a continuous dissolution reaction; the pressure sensors in the reactor monitor the pressure in the chamber to ensure stable operating pressure. (5) Gas processing The mixed gas of hydrogen and water vapor generated by the reaction enters the dehydration and drying device through the outlet pipeline to remove water vapor, so that the water vapor content at the outlet is ≤5% RH; the dehydrated gas enters the gas pressure detection unit, the flow meter records the gas volume, and the control system automatically calculates the molar amount of hydrogen emission and the generation rate through the ideal gas law, and the data is displayed and stored in real time. (6) Circulation The reacted salt solution flows back to the main storage tank through pipelines, forming a closed loop; the detected hydrogen enters the hydrogen compressor, is compressed and stored in the hydrogen collection tank, undergoes primary harmless treatment and then enters the professional treatment system; the detected liquid and solid reaction products are collected into the collection tank, undergo primary harmless treatment and then enter the professional treatment system.

[0020] Preferably, in step (5) above, the selection and combination of measurement methods are based on the type of dissolution reaction and the changes in products and concentrations of the specific system to be tested: If the dissolution reaction produces gas, and the change in the amount of a single gas produced can determine the extent and rate of the reaction, then the pressure and flow rate of the single gas can be used to indicate the reaction rate. If the change in the amount of a single gas produced is insufficient to fully indicate the dissolution reaction rate, a pH meter should be used to measure the change in the pH value of the products before and after the reaction; or an ORP test should be used to measure the change in the redox potential of a substance before and after the reaction; or an ion-selective electrode test should be used to measure the ion concentration characteristics; or a spectral analysis should be performed to measure the change in the spectrum of a substance before and after the reaction; or any combination of the above test methods. If no gas is produced in the dissolution reaction products, and only the liquid and solid phase products change, then one or more test combinations as described in claim 1 can be selected to characterize and measure the dissolution reaction rate based on the changes in pH value, redox potential, selective ion characteristic potential, characteristic spectral data, etc. of the products before and after the dissolution reaction. The test unit of the test method includes test modules for pressure, flow rate, concentration, ion electrochemical characteristics, phase spectral characteristics, PH-ORP, etc., and corresponding data processing modules for selection. Depending on the type of dissolution reaction to be tested, single-channel, multi-channel, or full-channel tests can be used to perform dissolution tests on metal materials for different test requirements.

[0021] Specifically, this application provides a dissolution testing method for soluble metals, applicable to magnesium-based soluble materials, such as bridge plugs, sliding sleeves, and fracturing balls used in downhole fracturing. This dissolution testing device and method use a chloride-based electrolyte solution, such as potassium chloride or sodium chloride, to record the dissolution rate and state of the magnesium-based soluble material in real time. The evaluation of the dissolution rate relies on the dissolution of magnesium-based and aluminum-based soluble materials in the electrolyte solution and the release of hydrogen gas. The device monitors the hydrogen content in the reaction products in real time to calculate the reaction rate. Chloride ions ionized from the chloride-based electrolyte solution can disrupt the integrity of the oxide film, reduce solution resistance, accelerate the electrochemical reaction, and further increase the dissolution rate with increasing concentration. Increased temperature increases ion migration rate and reaction activation energy, significantly accelerating anodic dissolution and cathodic hydrogen evolution rates, and shortening the dissolution time.

[0022] Taking magnesium alloys as an example, the reaction occurring in a potassium chloride aqueous solution is essentially the electrochemical corrosion of magnesium. The overall reaction involves magnesium reacting with water to produce hydrogen gas and magnesium hydroxide. In this reaction, the potassium chloride solution acts as an electrolyte, increasing the solution's conductivity and accelerating electron transfer. Chloride ions are corrosive and can damage the passivation film on the magnesium surface, making corrosion easier. While potassium and chloride ions themselves do not participate in the reaction, the localized acidification effect of chloride ions promotes hydrogen evolution.

[0023] The chemical reaction equation is as follows:

[0024] This application enables process data monitoring, gas composition analysis, continuous regulation and control, and remote monitoring and interlocking. It allows for process flow display, gas detection data viewing, remote operation control, and alarm record querying via a graphical interface. It supports both local and remote control modes; in remote mode, it allows for parameter setting, equipment start / stop, and alarm push notifications, meeting the needs of unattended testing. Data acquisition and storage involves real-time acquisition of parameters such as temperature, pressure, circulation flow rate, replacement flow rate, hydrogen content, water vapor content, and solution concentration at a frequency of once per minute. Data is automatically stored on the industrial control computer's hard drive and a cloud server. Data storage periods and export rules can be set to create a complete test data record.

[0025] The following test examples document the results for magnesium-based and aluminum-based soluble materials. Real-time data is recorded as the amount of hydrogen produced by the dissolution process; the actual dissolution rate of the material is directly output via computer data processing. The following examples output data as the amount of hydrogen produced by the untreated product, to facilitate a practical understanding of the device.

[0026] Test Example 1 The total weight of the φ106 soluble bridge plug (excluding the rubber sleeve) is 3.97 kg. This includes 0.194 kg of zirconia ceramic slips, totaling 3.776 kg of soluble material, and 0.27 kg of soluble material from the matching soluble balls. The soluble magnesium alloy material contains approximately 92-93% magnesium, resulting in a total magnesium content of 3.72 kg for the bridge plug and balls. 120 g of analytical grade potassium chloride and 120 L of pure water were mixed thoroughly to obtain a 0.1% potassium chloride standard solution. The solution was placed in a high-temperature, high-pressure reactor, sealed, and purged with nitrogen three times at 2 MPa each time for 5 minutes before venting. The temperature control system was then activated, increasing the temperature to 80 ± 2 °C at a rate of 5 °C / min. The hydrogen molar quantity was measured every 4 hours using the hydrogen metering module in the high-temperature reactor. The reaction continued until complete dissolution and no further change in gas production, at which point the test was stopped.

[0027] Test results: The reaction lasted for 100 hours. According to the hydrogen metering module in the high-temperature reactor, the total amount of hydrogen produced was 155 mol. The hydrogen production rate per unit time was: 4.97 mol / h average from 0-24 hours, 1.26 mol / h average from 24-48 hours, 0.16 mol / h average from 48-72 hours, 0.06 mol / h average from 72-96 hours, and an overall average of 1.61 mol / h. Detailed reaction data curves are available in [link to curve]. Figure 1 .

[0028] Test Example 2 AG52 soluble extruded rods were processed into φ20*20mm samples, weighing 11.737g, with a total magnesium mass of 10.798g. The experiment was conducted using a 0.84% ​​potassium chloride standard solution following the steps in Example 1. The temperature control system was activated, and the temperature was increased to 50±2℃ at a rate of 5℃ / min. The molar amount of hydrogen was recorded hourly using the hydrogen metering module in the high-temperature reactor.

[0029] Test results: The reaction lasted for 20 hours. According to the hydrogen metering module of the high-temperature reactor, the total amount of hydrogen produced was 0.44 mol; the hydrogen production rate per unit time was 4*10^6 mol / L on average from 0 to 5 hours. -2 mol / h, average 2.8*10 over 5-10 hours -2 mol / h, average 1.5*10⁻¹⁵h. -2 mol / h, average 0.6*10 over 15-20 hours. -2 mol / h, with an average of 2.3*10⁻⁶ throughout the process. -2 mol / h. Detailed reaction data curves can be found in [reference needed]. Figure 2 .

[0030] Test Example 3 AG23 soluble extruded rods were processed into φ20*20mm samples, weighing 11.25g, with a total magnesium mass of 10.35g. The experiment was conducted using a 3% potassium chloride standard solution following the steps in Example 1. The temperature control system was activated, and the temperature was increased to 130±2℃ at a rate of 5℃ / min. The molar amount of hydrogen was recorded hourly using the hydrogen metering module in the high-temperature reactor.

[0031] Test results: The reaction lasted for 8 hours. According to the hydrogen metering module of the high-temperature reactor, the total amount of hydrogen produced was 0.42 mol; the hydrogen production rate per unit time was 6.44 × 10⁻⁶ per hour (0-2 hours). -2 mol / h, average 9.16*10⁻⁴ h over 2-4 h. -2 mol / h, average 4.46*10 over 4-6 hours -2 mol / h, average 0.94*10 over 6-8 hours. -2 mol / h, with an average of 5.52*10⁻⁶ throughout the process. -2 mol / h. See detailed reaction rate. Figure 3 .

[0032] Although the embodiments disclosed in this application are as described above, the content is merely for the purpose of facilitating understanding of this application and is not intended to limit this application. Any person skilled in the art to which this application pertains may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in this application; however, the scope of patent protection of this application shall still be determined by the scope defined in the appended claims.

Claims

1. A method for testing the solubility of soluble metals, characterized in that, Continuous real-time testing of soluble metallic materials in different dissolving media, ranging from below the boiling point of the dissolving media at atmospheric pressure to well above the boiling point of the dissolving media at atmospheric pressure, specifically includes the following steps: By utilizing the difference in saturated vapor pressure of a solution at different temperatures, different pressures are applied to the dissolving medium to adjust its boiling point temperature, thereby causing the dissolution reaction to occur at a boiling point of the dissolving medium below or above the boiling point of the dissolving medium at atmospheric pressure; the dissolving medium can be an aqueous dispersion or a non-aqueous dispersion. The dissolution test is conducted continuously and without interruption within a closed reaction unit using online detection. The testing device comprehensively simulates the dissolution process, and measures and provides feedback on the dissolution rate in real time. The increase or decrease in the amount of dissolved products causes changes in the pressure, flow rate, concentration, ionic electrochemical characteristics, phase spectrum characteristics, and pH-ORP characteristics of the test device system. The real-time change in the amount of dissolved products is obtained by testing at least one of the above parameters through the test device. The dissolution rate of the metal dissolution reaction is calculated using the real-time amount of dissolved products obtained. The dissolution rate value is directly output through data processing.

2. The dissolution test method according to claim 1, characterized in that, When the required test temperature is higher than the boiling point of the dissolving medium, the pressure inside the dissolving reaction unit is increased to make the boiling point of the dissolving medium greater than or equal to the required test temperature, and the dissolving medium is heated to the required test temperature to conduct the dissolution rate test.

3. The dissolution test method according to claim 1, characterized in that, The equipment test parameters are selected and adjusted by using the boiling point and saturated vapor pressure of the dispersion solution to determine the test temperature or pressure.

4. The dissolution test method according to claim 1, characterized in that, The dissolution rate is characterized by the rate of formation of the dissolved products, which are at least one of gas, liquid and solid. The method obtains the dissolution reaction rate by separating the dissolved products, quantitatively testing one or more products with certain characteristics according to their performance characteristics online, and simultaneously processing the data.

5. The dissolution test method according to claim 4, characterized in that, The testing device includes a dissolution reaction unit, which is connected to a dissolution medium storage unit and a dissolution product detection unit; the dissolution medium storage unit is connected to the dissolution reaction unit through a circulation unit. The dissolution product detection unit is equipped to detect the amount of products generated in the dissolution reaction unit; the pressure inside the dissolution reaction unit satisfies the requirement that the boiling point of the dissolution medium is greater than or equal to the test temperature under this pressure.

6. The dissolution test method according to claim 5, characterized in that, The internal pressure of the dissolution reaction unit is controlled at 0.1-4 MPa by a pressure control device, so that the dissolution medium inside the dissolution reaction unit is maintained above the atmospheric boiling point of the dissolution medium.

7. The dissolution test method according to claim 6, characterized in that, When the required test temperature is lower than the boiling point of the dissolved medium, the pressure control device controls the pressure inside the dissolution reaction unit at 1 atmosphere; when the required test temperature is higher than the boiling point of the dissolved medium, the pressure control device increases the pressure inside the dissolution reaction unit to make the boiling point of the dissolved medium greater than or equal to the required test temperature, so as to maintain the test temperature.

8. The dissolution test method according to claim 5, characterized in that, The testing device also includes a control unit, which includes a controller, a human-machine interface device, and a control module. The control module includes a multi-loop PID temperature control unit, a pressure monitoring and interlock control unit, a concentration detection, a liquid level monitoring and interlock control unit, and a safety interlock protection unit. The safety interlock protection unit includes at least one of a pressure alarm module, a temperature alarm module, a liquid level over-limit module, and a gas leak alarm module.

9. The dissolution test method according to any one of claims 1-8, characterized in that, It also includes the following steps: (1) Inject the concentrated dissolving medium and dispersant into the storage tank according to the concentration to reach the required concentration of dissolving medium; turn on the liquid level detection and concentration detection module, remove impurities through the filter and pump into the circulation power unit; (2) Set the target temperature and start the heating device. The temperature control system uses the real-time data fed back by the temperature sensor to control the heating power using the adjustment algorithm, so that the temperature of the medium solution gradually rises to the set value and stabilizes. The system pressure stabilizes in the range of 0.1-4MPa after the temperature rises to the target temperature. The pressure sensor feeds back the data in real time. When the pressure exceeds 4.1 MPa, the unloading valve automatically opens to release pressure to 4MPa. If the pressure exceeds 4.5MPa, the system issues an audible and visual alarm and starts the emergency shutdown procedure. After the delivery pump heats the medium solution to the set temperature, it enters the reactor of the dissolution reaction unit. (3) The medium solution after temperature adjustment enters the reactor and comes into full contact with the sample to be tested in the reactor to carry out a continuous dissolution reaction; the pressure sensors of the reactor monitor the pressure in the chamber to ensure stable operating pressure; (4) The mixture of gas and water vapor generated by the reaction enters the dehydration and drying device through the outlet pipeline to remove water vapor, so that the water vapor content at the outlet is ≤5% RH; the dehydrated gas enters the gas pressure detection unit, the flow meter records the gas volume, and the control system automatically calculates the gas emission molar amount and generation rate through the ideal gas state equation. The data is displayed and stored in real time; other gases or compounds generated by the reaction enter the test unit through one or more methods selected from filtration, separation, membrane treatment, and molecular sieve treatment. (5) The test unit includes online measurement methods selected from flow rate, pressure, selective electrode, electrode potential, spectrum, and pH value to quantitatively detect, measure, and record the formation rate of dissolved products; (6) The reaction medium solution is returned to the main storage tank through the pipeline to form a closed loop; the detected gas enters the compressor, is compressed and stored in the collection tank.

10. The dissolution test method according to claim 9, characterized in that, In step (5), the selection of measurement methods is based on the combination of products and concentration changes of the dissolution reaction of the specific system to be tested; When a gas is generated from the dissolution reaction products, and the change in the amount of a single gas generated can determine the reaction rate, the reaction rate is identified by the measurement data of the pressure and flow rate of the single gas. If the change in the amount of a single gas generated is insufficient to fully identify the dissolution reaction rate, the pH value of the products before and after the reaction is measured, or the redox potential of a certain substance before and after the reaction is tested, or ion-selective electrode testing is performed based on the ion concentration characteristics, or spectral analysis is performed based on the spectral changes of a certain substance before and after the reaction, or a combination of at least two of the above methods is used. When no gas is produced in the dissolution reaction, and only the liquid and solid phases change, the dissolution reaction rate is characterized by at least one of the changes in pH value, redox potential, selective ion characteristic potential, or characteristic spectral data of the products before and after the dissolution reaction.

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