Decomposition equipment for recycling metal gallium by using high temperature and reaction gas

Abstract

The invention relates to decomposition equipment for recycling metal gallium by using high temperature and reaction gas, which comprises a reaction cavity with a gas inlet and a gas outlet, and a polycrystal decomposition box body which is arranged in the reaction cavity and is provided with a reaction gas inlet end and a reaction gas outlet end, a crucible used for containing gallium nitride polycrystals or metal gallium is arranged in the polycrystal decomposition box body, and permeation felt layers used for preventing the metal gallium from scattering outwards are arranged at the reaction gas inlet end and the reaction gas outlet end of the polycrystal decomposition box body. According to the invention, the uniformity of the atmosphere in the polycrystalline decomposition box body is realized, and the liquid metal gallium formed after decomposition in the crucible cannot reversely flow out of the permeable felt layer at high temperature and can be collected in the polycrystalline decomposition box; the method effectively solves the industrial technical problem that after gallium nitride polycrystals are decomposed at a high temperature, metal gallium flows around along with airflow and is randomly adhered in a cavity after being cooled, and collection cannot be realized.

Description

Technical Field

[0002] The present invention belongs to the technical field of hydride vapor phase epitaxy (HVPE), and in particular relates to a decomposition device which utilizes high temperature and reaction gas to decompose a large amount of gallium nitride polycrystals into metal gallium and other gases in the device to realize the recovery of metal gallium. Background Art

[0003] When using the HVPE method to produce gallium nitride single crystals, since the gallium source utilization rate is only between 10-20%, the remaining 80%-90% of the gallium source will be converted into gallium nitride polycrystals during the process. Currently, how to deal with gallium nitride polycrystals to achieve metal gallium recovery and reduce raw material consumption has become a difficult problem in the industry.

[0004] However, the uneven auxiliary atmosphere on the surface of GaN polycrystals will lead to inconsistent decomposition effects. At high temperatures, after the GaN polycrystals are decomposed, if the structural design is unreasonable, the metallic gallium will flow around with the airflow, and after cooling, it will adhere randomly to the cavity and cannot be collected. Therefore, how to efficiently recover the metallic gallium in the GaN polycrystals through reasonable structural design has become a difficult point.

[0005] For example, the Chinese patent "A method for recovering gallium from waste containing gallium nitride" Publication No. CN103388159A comprises the following steps: (1) crushing gallium nitride-containing waste; (2) washing and drying the gallium nitride-containing waste powder obtained in (1), adding it to concentrated sulfuric acid, heating and filtering to obtain filter residue A; (3) adding water to dissolve the filter residue A, filtering to obtain filtrate B and filter residue B; (4) adding aqua regia to the filter residue B, stirring to react, filtering to obtain filter residue C and filtrate C; (5) washing and drying the filter residue C, adding it to a KOH ethylene glycol solution, stirring or ultrasonic vibration reaction, filtering to obtain a gallium-containing filtrate; (6) extracting the gallium-containing filtrate with Kelex-100 to separate a gallium-containing organic phase; (7) washing the gallium-containing organic phase with HCl solution, and then stripping gallium with HCl to obtain a gallium-containing aqueous solution; (8) using cyclone selective electrowinning of gallium. The invention can not only effectively solve the treatment problem of various gallium nitride-containing wastes, but also turn waste into treasure, effectively recover metallic gallium and thus obtain greater economic benefits; however, its process is complicated and the recovery cost is high. Summary of the invention

[0006] In view of the above problems in the prior art, an object of the present invention is to provide a decomposition device for recovering metal gallium using high temperature and reaction gas, which can achieve uniformity of the atmosphere in the polycrystalline decomposition box and is conducive to collecting metal gallium.

[0007] The present invention discloses a decomposition equipment for recovering gallium metal by utilizing high temperature and reaction gas, and is characterized in that it comprises a reaction chamber having a gas inlet and a gas outlet, and a polycrystalline decomposition box body arranged in the reaction chamber and having a reaction gas inlet end and a reaction gas outlet end, a heater is arranged on the periphery of the polycrystalline decomposition box, a crucible for containing gallium nitride polycrystal or gallium metal is arranged in the polycrystalline decomposition box body, and a permeable felt layer for blocking the diffusion of gallium metal is arranged on the reaction gas inlet end and the reaction gas outlet end of the polycrystalline decomposition box body.

[0008] Preferably, the gas flow directions of the gas inlet and the gas outlet of the reaction chamber are perpendicular to or consistent with the gas flow directions of the reaction gas inlet and the reaction gas outlet of the polycrystalline decomposition box.

[0009] Preferably, the gas inlet and the gas outlet, or the gas inlet or the gas outlet is connected to a pressure control device to maintain the pressure in the reaction chamber.

[0010] Preferably, the polycrystalline decomposition box comprises a vertically arranged support frame and the permeable felt layer fixed on the upper and lower ends of the support frame.

[0011] Preferably, the reaction gas introduced into the gas inlet is a mixed gas of at least one or more of N2, H2, HCl, and Cl2.

[0012] Preferably, the heating of the heater is to achieve temperature control in the reaction chamber and the polycrystalline decomposition box at 0°C-1500°C.

[0013] Preferably, the outer dimensions of the above-mentioned polycrystalline decomposition box are 10-2000 mm, the outer dimensions of the reaction chamber 103 are 50-5000 mm, the heater provides the temperature required for the process 0-1500 ° C, the pressure control device adjusts the pressure range of the reaction chamber 0-1000 mbar, and the outer dimensions of the support frame are 10-3000 mm.

[0014] Preferably, the permeable felt layer is a porous high temperature resistant cotton felt with a thickness of 0.1-50 mm and a size of 10-3000 mm. The pore size range of the cotton felt is 0.1-10 mm.

[0015] Preferably, the crucible is made of high temperature resistant material and has a size of 10-1000 mm.

[0016] The decomposition equipment of the present invention utilizes high temperature and reaction gas to realize the recovery of metal gallium. Through a polycrystalline decomposition box and a permeable felt layer coated on the reaction gas inlet and the reaction gas outlet, the atmosphere in the reaction chamber enters the polycrystalline decomposition box by infiltration. At the same time, the gallium nitride polycrystals in the crucible in the polycrystalline decomposition box are of a loose porous structure. Through the above method, the uniformity of the atmosphere in the polycrystalline decomposition box can be achieved, and at high temperature, the liquid metal gallium formed after decomposition in the crucible cannot flow out from the permeable felt layer in the reverse direction, and can be collected in the polycrystalline decomposition box; therefore, the equipment can make the auxiliary atmosphere on the surface of the gallium nitride polycrystal uniform through reasonable structural design so as to achieve a consistent decomposition effect, and effectively solves the industry technical problem that after the gallium nitride polycrystals are decomposed at high temperature, the metal gallium will flow around with the airflow, and will randomly adhere to the cavity after cooling, and cannot be collected; the decomposition equipment of the present invention for the recovery of metal gallium has a simple structure, is easy to manufacture and has low cost, and is conducive to the centralized recovery of metal gallium. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a decomposition equipment for realizing metal gallium recovery by utilizing high temperature and reaction gas according to a preferred embodiment of the present invention; Figure 2 It is a structural schematic diagram of a polycrystalline decomposition box of a decomposition equipment for realizing metal gallium recovery by utilizing high temperature and reaction gas according to a preferred embodiment of the present invention.

[0018] In the figure: 101 gas inlet, 102 polycrystalline decomposition box, 103 reaction chamber, 104 adder, 105 gas inflow direction, 106 gas outflow direction, 107 pressure control device, 108 gas outlet, 201 support frame, 202 infiltration felt layer, 203 gallium nitride polycrystalline, 204 gas infiltration direction, 205 crucible, 206, reaction gas inlet, 207 reaction gas outlet. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0020] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0021] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0022] Reference Figure 1 A decomposition equipment for recovering metallic gallium using high temperature and reaction gas includes a reaction chamber 103 having a gas inlet 101 and a gas outlet 108 and a polycrystalline decomposition box 102 arranged in the reaction chamber and having a reaction gas inlet 206 and a reaction gas outlet 207. The reaction chamber 103 is a closed chamber, and only the gas inlet 101 and the gas outlet 108 are arranged for the input and output of the reaction gas.

[0023] The reaction gas introduced into the gas inlet 101 may be at least one or more mixed gases of N2, H2, HCl, and Cl2; the gas flow direction of the gas inlet 101 and the gas outlet 108 of the reaction chamber is perpendicular or consistent with the gas flow direction of the reaction gas inlet 206 and the reaction gas outlet 207 of the polycrystalline decomposition box, that is, the gas inflow direction 105, the gas outflow direction 106 and the gas infiltration direction 204 are perpendicular or consistent, Figure 1 As shown, the gas inflow direction 105 and the gas outflow direction 106 are perpendicular to the gas infiltration direction 204 .

[0024] In order to ensure the pressure in the reaction chamber, the gas inlet and the gas outlet are connected to a pressure control device, or the gas inlet 101 or the gas outlet 108 is connected to a pressure control device 107 to maintain the pressure in the reaction chamber. The pressure control device 107 can be an air compressor, etc. The pressure control device is an existing equipment, and the specific connection will not be repeated here.

[0025] The polycrystalline decomposition box 102 includes a vertically arranged support frame 201 and the permeable felt layer 202 fixed on the upper and lower ends of the support frame. The support frame 201 can be used as the frame of the polycrystalline decomposition box 102 and is used to install the permeable felt layer 202. The permeable felt layer 202 covers the reaction gas inlet and reaction gas outlet of the polycrystalline decomposition box to block the outward dispersion of the metallic gallium after the decomposition of the gallium nitride polycrystal 203; the permeable felt layer 202 is a porous high-temperature resistant cotton felt with a thickness of 0.1-50 mm and a size of 10-3000 mm. The pore size range of the cotton felt is 0.1-10 mm.

[0026] A heater 104 is provided on the periphery of the polycrystalline decomposition box. The heater 104 is an electric heater such as an electric heating wire to provide a high temperature environment for the reaction. The heating of the heater can achieve temperature control in the reaction chamber and the polycrystalline decomposition box at 0°C-1500°C.

[0027] A crucible 205 for containing gallium nitride polycrystal 203 or metal gallium is provided in the polycrystal decomposition box. The crucible 205 is made of high temperature resistant material and has a size of 10-1000 mm.

[0028] The dimensions of the polycrystalline decomposition box 102 are 10-2000 mm, the dimensions of the reaction chamber 103 are 50-5000 mm, the heater 104 provides the temperature required for the process at 0-1500 °C, the pressure control device 107 adjusts the pressure range of the reaction chamber at 0-1000 mbar, and the dimensions of the support frame 201 are 10-3000 mm.

[0029] In a specific embodiment, the polycrystalline decomposition box 102 is covered with a permeable felt layer 202 on the top and bottom, and the atmosphere in the reaction chamber enters the polycrystalline decomposition box 102 by permeation. At the same time, the gallium nitride polycrystal 203 is a loose porous structure. Through the above method, the uniformity of the atmosphere in the polycrystalline decomposition box 102 can be achieved. Due to the design of the permeable felt layer 202, liquid metal gallium cannot flow out of the permeable felt layer 202 at high temperature and can be collected in the polycrystalline decomposition box 102; the permeable felt layer 202 covers the upper and lower surfaces of the polycrystalline decomposition box 102; the heater 104 is placed around the polycrystalline decomposition box 102; the gas permeation direction 204 is from the reaction chamber 103 through the permeable felt layer 202 to the inside of the polycrystalline decomposition box 102; the reaction gas is introduced from the gas inlet 10 1. The gas flows into the reaction chamber 103 in the direction of gas inflow 105, and leaves the reaction chamber 103 in the direction of gas outflow 106 through a pressure control device 107 that can realize pressure regulation in the chamber; the gallium nitride polycrystal 203 is placed in a crucible 205; the crucible 205 is placed in a polycrystal decomposition box 102, and a support frame 201 supports a permeable felt layer 202; the crucible 205 is made of a high-temperature resistant material, and is used to hold the gallium nitride polycrystal 203, and after decomposition, to hold metal gallium; therefore, the device can make the auxiliary atmosphere on the surface of the gallium nitride polycrystal uniform through a reasonable permeable felt structure design, so that the decomposition effect is consistent, and effectively solves the industry technical problem that after the gallium nitride polycrystal is decomposed at high temperature, the metal gallium will flow around with the airflow, and will adhere to the chamber at will after cooling, and cannot be collected.

[0030] Embodiment 1: 1. The reaction chamber of this embodiment adopts a cylindrical structure with a diameter of 8000 mm and a length of 1000 mm; 2. Example The infiltration cotton felt is made of 20 mm loose porous graphite felt, the pore diameter is in the range of 0.1-1 mm, and the pore diameter gradually increases from the inside to the outside of the box; 3. Example The dimensions of the polycrystalline decomposition box are 300*200*300mm in length, width and height respectively; 4. The specific pressure range of this embodiment is 50-100 mbar, the H2 dosage is 5000-10000 sccm, and the N2 dosage is 5000-10000 sccm; 5. The specific temperature of this embodiment is 1400°C; 6. In this embodiment, 2.1 kg of gallium nitride polycrystals were input and 1.3 kg of metallic gallium was actually recovered.

[0031] Embodiment two: 1. The reaction chamber of this embodiment adopts a cylindrical structure with a diameter of 8000 mm and a length of 1000 mm; 2. Example The infiltration cotton felt is made of 20 mm loose porous graphite felt, the pore diameter is in the range of 0.1-1 mm, and the pore diameter gradually increases from the inside to the outside of the box; 3. Example The dimensions of the polycrystalline decomposition box are 300*200*300 mm in length, width and height respectively; 4. The specific pressure range of this embodiment is 10-50 mbar, the H2 dosage is 1000-5000 sccm, and the N2 dosage is 5000-10000 sccm; 5. The specific temperature of this embodiment is 1500°C; 6. In this example, 2.1 kg of gallium nitride polycrystals were input and 1.0 kg of metallic gallium was actually recovered.

[0032] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection: it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0033] Equipment includes not only those elements, but also other elements that are not clearly listed, or also includes elements inherent to such processes, methods, articles or equipment. In the absence of more restrictions, the elements limited by the sentence "including one" do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. The above is only a specific implementation of the application, so that those skilled in the art can understand or implement the application. It will be obvious to those skilled in the art to modify these embodiments, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application will not be limited to these embodiments shown in this article, but will meet the widest scope consistent with the principles and novel features applied for herein.

Claims

1. A decomposition device for recovering gallium metal by using high temperature and reaction gas, characterized in that: The invention comprises a reaction chamber with a gas inlet and a gas outlet, and a polycrystalline decomposition box body arranged in the reaction chamber and having a reaction gas inlet end and a reaction gas outlet end. A heater is arranged on the periphery of the polycrystalline decomposition box, a crucible for containing gallium nitride polycrystal or metallic gallium is arranged in the polycrystalline decomposition box body, and a permeable felt layer for blocking the diffusion of metallic gallium is arranged on the reaction gas inlet end and the reaction gas outlet end of the polycrystalline decomposition box body.

2. The decomposition equipment for recovering gallium metal by using high temperature and reaction gas according to claim 1, characterized in that: The gas flow directions of the gas inlet and the gas outlet of the reaction chamber are perpendicular to or consistent with the gas flow directions of the reaction gas inlet and the reaction gas outlet of the polycrystalline decomposition box.

3. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 1 or 2, characterized in that: The gas inlet and the gas outlet, or the gas inlet or the gas outlet is connected to a pressure control device to maintain the pressure in the reaction chamber.

4. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 3, characterized in that: The polycrystalline decomposition box comprises a vertically arranged support frame and the permeable felt layer fixed on the upper and lower ends of the support frame.

5. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 1, characterized in that: The reaction gas introduced into the gas inlet is at least one or more mixed gases of N2, H2, HCl, and Cl2.

6. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 1, characterized in that: The heater is used to heat the reaction chamber and the polycrystalline decomposition box so that the temperature is controlled within the range of 0°C to 1500°C.

7. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 1, characterized in that: The outer dimensions of the polycrystalline decomposition box are 10-2000 mm, the outer dimensions of the reaction chamber are 50-5000 mm, the heater provides the temperature required for the process at 0-1500 °C, the pressure control device adjusts the pressure range of the reaction chamber at 0-1000 mbar, and the outer dimensions of the support frame 201 are 10-3000 mm.

8. The decomposition equipment for recovering gallium metal by using high temperature and reaction gas according to claim 1, characterized in that: The permeable felt layer is a porous high temperature resistant cotton felt with a thickness of 0.1-50 mm and a size of 10-3000 mm. The aperture range of the cotton felt is 0.1-10 mm.

9. The decomposition equipment for recovering metal gallium by using high temperature and reaction gas according to claim 1, characterized in that: The crucible is made of high temperature resistant material and has a size of 10-1000 mm.

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