Metal powder dissolution condition detection system

Abstract

The invention relates to a system for detecting the dissolution condition of metal powder. The system comprises (1) a reaction kettle; (2) a stirrer; (3) a sound wave transmitter; (4) a sound wave detector; (5) a sound wave recorder; the sound wave detector is connected with the reaction kettle through a sound wave transmission line and is used for detecting the frequency of sound waves in the reaction kettle, detected signals are recorded in the sound wave recorder, and the sound wave filtering classification detection system is used for comparing the signals of the blank control sample to detect the frequency of the sound waves in the reaction kettle. And filtering to obtain the real-time online sound wave frequency of the metal powder dissolution condition. The detection system can detect the dissolving condition of the powder particles in the reaction kettle in the closed space under the closed condition, so that the production efficiency is improved, the safety and environmental protection risks caused by manual operation and visual inspection for checking the internal condition are avoided, and the detection system has a good industrial application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst preparation, and in particular relates to a system for detecting the dissolution status of metal powder in a reaction kettle. Background Art

[0002] Precious metals such as platinum, palladium, rhodium, and iridium are widely used in the preparation of catalysts for volatile organic compounds (VOCs) treatment, motor vehicle exhaust purification, catalytic hydrogenation, and propane dehydrogenation. The precursors of these catalysts are mainly concentrated in rhodium nitrate, platinum nitrate, palladium nitrate, rhodium trichloride, chloroplatinic acid, palladium chloride, etc. These precious metal compounds are obtained by dissolving platinum, palladium, and rhodium powders (content 99.95%) from mines or recycling. However, the color of the solution after the precious metals are dissolved is very dark, and it is difficult to distinguish the dissolution status with the naked eye. In particular, some precious metal dissolution processes use a highly dangerous process of chlorine plus hydrochloric acid, which must be operated in a closed environment and cannot be observed. It is impossible to check the solubility or dissolution status of the metal powder in real time.

[0003] The following problems often exist in the processing of precious metal powders: 1. Precious metal prices fluctuate greatly. If they are left idle for a long time without being processed, it is difficult to cope with market changes, which requires customers to endure a longer precious metal cycle, which is not conducive to commercial flow; 2. There is no standard and basically unified source of metal raw materials for the above-mentioned precious metal powders on the market. The metal powders of various suppliers often have obvious differences, different dissolution times, and different solubilities; 3. The current precious metal dissolution processes at home and abroad usually adopt the steps of manually opening the reactor and manually checking the internal dissolution situation. The opening operation during the dissolution process increases the risk of leakage and the difficulty of operation, which increases environmental and safety risks, and is not conducive to the control of process nodes in the production process. Summary of the invention

[0004] In order to overcome and make up for the above-mentioned deficiencies in the prior art, facilitate online monitoring of the dissolution of metal powders, and understand the production progress in real time, the present invention introduces an acoustic wave monitoring and acoustic wave filtering classification detection system to understand the dissolution of metal powders in the closed system in real time, thereby formulating targeted process control measures. Specifically, the technical solution adopted by the present invention is as follows:

[0005] On the one hand, the present invention provides a metal powder dissolution condition detection system, which includes: (1) a reactor; (2) an agitator; (3) an acoustic wave transmission line; (4) an acoustic wave detector; (5) an acoustic wave recorder; (6) an acoustic wave filtering and classification detection system, wherein the acoustic wave detector is connected to the reactor through the acoustic wave transmission line to detect the frequency of the acoustic wave in the reactor, and the detected signal is recorded in the acoustic wave recorder. At the same time, the acoustic wave filtering and classification detection system compares the acoustic wave frequency of a blank control sample to filter and obtain the real-time online acoustic frequency of the metal powder dissolution condition.

[0006] Furthermore, in the metal powder dissolution condition detection system of the present invention, the reaction kettle is selected from one of a glass kettle, a polytetrafluoroethylene kettle, an enamel kettle, a stainless steel kettle, a plastic kettle, and a resin kettle.

[0007] Furthermore, in the metal powder dissolution condition detection system of the present invention, the acoustic wave transmission line can be connected inside the kettle or outside the kettle.

[0008] Furthermore, in the metal powder dissolution condition detection system of the present invention, the effective usable frequency detected by the acoustic wave detector is 1 to 20,000 Hz.

[0009] Furthermore, in the metal powder dissolution condition detection system described in the present invention, the sound waves filtered by the sound wave filtering and classification detection system include: sound waves from the agitator motor, sound waves from the collision between the solution and the wall of the reactor, sound waves from the stirring of the agitator paddle and the solution, and sound waves from the noise in the environment.

[0010] Furthermore, in the metal powder dissolution condition detection system of the present invention: the metal powder is selected from one or more of platinum powder, palladium powder, gold powder, rhodium powder, iridium powder, and ruthenium powder.

[0011] On the other hand, the present invention provides a method for detecting the dissolution status of metal powder. The method uses the metal powder dissolution status detection system described above to detect the sound wave frequency in the reactor in real time to obtain the dynamic status of the metal powder dissolution in the reactor.

[0012] The present invention introduces an acoustic wave monitoring and acoustic wave filtering classification detection system, firstly monitors the background acoustic wave frequency, and then obtains the characteristic acoustic wave frequency of the collision between the metal powder and the wall of the reactor and the collision between the metal powders through acoustic wave filtering classification, and obtains the dissolution of the metal through the characteristic acoustic wave frequency. The acoustic wave monitoring monitors the acoustic wave information of the reactor in real time, and the acoustic wave filtering classification detection system records the background acoustic wave of the reactor system without adding metal powder, and automatically filters the background acoustic wave of the reactor system during the dissolution of the metal powder to obtain the acoustic wave frequency in the presence of metal powder. Of course, as the metal powder gradually dissolves and the particles become smaller, the corresponding frequency will gradually change, and the intensity will gradually decrease. The acoustic wave filtering classification detection system monitors the corresponding band and intensity changes, which correspond to the dissolution situation one by one, thereby realizing the node control of the metal powder dissolution process.

[0013] The advantages and beneficial effects of the present invention are:

[0014] 1. The dissolution status of metal powder in the closed environment of the reactor can be monitored in real time, which not only improves production efficiency, but also avoids the safety and environmental risks caused by manually opening the reactor and visually checking the internal dissolution status.

[0015] 2. The metal powder dissolution curve can be drawn as needed to fully understand the dissolution degree inside the reactor and provide more accurate process node control for the catalyst production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the powder dissolution condition detection system of the present invention.

[0017] The accompanying drawings are described as follows: (1) reaction kettle; (2) stirring paddle; (3) sound wave transmission line; (4) sound wave detector; (5) sound wave recorder; (6) sound wave filtering and classification detection system. DETAILED DESCRIPTION

[0018] The technical scheme of the present invention is specifically described below in conjunction with the embodiments and the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention. The raw materials, reagents, equipment, etc. used in the following embodiments are all commercially available or conventionally available.

[0019] As described in the present invention, the sound wave frequency described in the present invention refers to the speed of sound fluctuations, which is usually described in Hertz (Hz).

[0020] As described in the present invention, the sound waves detected by the sound wave detector described in the present invention are a combination composed of a specific set of sound wave frequencies.

[0021] As described in the present invention, the sound waves filtered by the sound wave filtering classification detection system described in the present invention include but are not limited to: sound waves from the agitator motor, sound waves from the collision between the solution and the wall of the reactor, sound waves from the stirring of the agitator paddle and the solution, sound waves from the noise in the environment, etc.

[0022] Example 1

[0023] 50L enamel reactor, reactor with mechanical stirring, add 25L 35% concentrated hydrochloric acid, 5L deionized water, 100g rhodium powder, closed reactor, stirring speed is adjusted to 300rpm, heated to 80°C, and chlorine is started. The surface of the reactor is connected to an acoustic transmission line, which is then connected to an acoustic detector, which is then recorded by an acoustic wave recorder through an acoustic filter classification detection system. After chlorine is passed into the reactor, there is the acoustic frequency of concentrated hydrochloric acid and rhodium powder, and the acoustic frequency at this time is recorded. After reacting for 3 days, the reactor is opened to confirm that the rhodium powder in the reactor is completely dissolved, and it is stirred again, and the stirring speed is adjusted to 300rpm, and the temperature rises to 80°C, and the acoustic frequency of the reactor is tested again, and the acoustic frequency at this time is recorded.

[0024] Note: The acoustic wave detector uses the Danish Reson TC4013 hydrophone with a frequency range of 1Hz-170kHz and each test time of 2s.

[0025] Comparative Example 1

[0026] A 50L enamel reactor with mechanical stirring is used, the stirring speed is adjusted to 300rpm, and the reactor is heated to 80°C. The surface of the reactor is connected to a sonic transmission line, which is then connected to a sonic detector and transmitted to a sonic recorder to record the sonic frequency at this time.

[0027] Comparative Example 2

[0028] A 50L enamel reactor with mechanical stirring was added with 25L 35% concentrated hydrochloric acid, 5L deionized water, and 100g rhodium powder, the stirring speed was adjusted to 300rpm, and the mixture was heated to 80°C. The surface of the reactor was connected with an acoustic wave transmission line, which was then connected to an acoustic wave detector. The acoustic wave detector detected the acoustic wave frequency of concentrated hydrochloric acid and rhodium powder in the reactor through an acoustic wave filtering and classification detection system, and the acoustic wave frequency at this time was recorded using an acoustic wave recorder.

[0029] Results: The frequency data recorded in Example 1 and Comparative Examples 1 and 2 are shown in Table 1 below:

[0030] Table 1:

[0031]

[0032] As can be seen from the above table 1, the sound wave frequencies 892.3Hz, 1520.9Hz, 1639.5Hz, 2677.8Hz, 3052.3Hz in comparative example 1 are the background sound wave frequencies of the single open reactor. Hydrochloric acid, water and rhodium powder are added in comparative example 2, and the sound wave frequencies of 462.3Hz, 759.1Hz, 1709.3Hz, 2219.9Hz, and 4010.4Hz are increased without passing chlorine. After passing chlorine in embodiment 1, rhodium powder begins to dissolve at this moment, and compared with comparative example 2, two characteristic frequencies 970.2Hz and 1839.0Hz are newly added, indicating that chlorine is bubbled into the solution and two characteristic frequencies are newly added. After the rhodium powder is thoroughly dissolved, these two characteristic frequencies disappear, indicating that the rhodium powder in the reactor is thoroughly dissolved, and chlorine is no longer needed, and the air inlet pipe pressure and the reactor pressure are balanced, and bubbling is not produced. The sound waves near the three frequencies of 462.3Hz, 1709.3Hz and 2219.9Hz disappeared, indicating that the rhodium powder was completely dissolved and the characteristic frequency of the rhodium powder disappeared.

[0033] Through the above-mentioned Example 1, it is shown that the present invention can monitor the dissolution status of metal powder in the closed environment of the reactor in real time, which improves the production efficiency on the one hand, and avoids the safety and environmental risks caused by manually opening the reactor and visually checking the internal dissolution status on the other hand. Furthermore, a curve of the dissolution degree of metal powder can be made as needed to fully understand the dissolution degree inside the reactor, providing more accurate process node control for the catalyst production process.

[0034] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the embodiments, ordinary technicians in the field should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be included in the scope of protection requested by the claims of the present invention.

Claims

1. A metal powder dissolution condition detection system, characterized in that include: (1) a reactor; (2) an agitator; (3) an acoustic wave transmission line; (4) an acoustic wave detector; (5) an acoustic wave recorder; and (6) an acoustic wave filtering and classification detection system, wherein the acoustic wave detector is connected to the reactor via the acoustic wave transmission line to detect the frequency of the acoustic waves in the reactor, and the detected signal is recorded in the acoustic wave recorder. At the same time, the acoustic wave filtering and classification detection system compares the acoustic wave frequency of a blank control sample to filter and obtain the real-time online acoustic wave frequency of the metal powder dissolution status.

2. The metal powder dissolution condition detection system according to claim 1, characterized in that: The reaction kettle is selected from a glass kettle, a PTFE kettle, an enamel kettle, a stainless steel kettle, a plastic kettle, and a resin kettle.

3. The metal powder dissolution condition detection system according to claim 1, characterized in that: The sound wave transmission line can be connected inside the kettle or outside the kettle.

4. The metal powder dissolution condition detection system according to claim 1, characterized in that: The effective usable frequency detected by the acoustic wave detector is 1-20000 Hz.

5. The metal powder dissolution condition detection system according to claim 1, characterized in that: The sound waves filtered by the sound wave filtering classification detection system include: sound waves of the stirrer motor, sound waves of the collision between the solution and the wall of the reactor, sound waves of the stirring of the stirring paddle and the solution, and sound waves of noise in the environment.

6. The metal powder dissolution condition detection system according to claim 1, characterized in that: The metal powder is selected from one or more of platinum powder, palladium powder, gold powder, rhodium powder, iridium powder and ruthenium powder.

7. A method for detecting the dissolution status of metal powder, characterized in that: The metal powder dissolution condition detection system according to claim 1 is used to detect the sound wave frequency in the reactor in real time to obtain the dynamic condition of the metal powder dissolution in the reactor.

Images