CN115094231A - Method for recovering metal resources in electronic component by using fluorine-chlorine organic compound - Google Patents
Method for recovering metal resources in electronic component by using fluorine-chlorine organic compound Download PDFInfo
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- CN115094231A CN115094231A CN202210723985.5A CN202210723985A CN115094231A CN 115094231 A CN115094231 A CN 115094231A CN 202210723985 A CN202210723985 A CN 202210723985A CN 115094231 A CN115094231 A CN 115094231A
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/005—Preliminary treatment of scrap
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/82—Recycling of waste of electrical or electronic equipment [WEEE]
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Abstract
The invention discloses a method for recycling metal resources in electronic components by using a fluorine-chlorine organic compound, and relates to the field of recycling of the electronic components. The method comprises the following steps: uniformly mixing deionized water, an oxidant and a fluorine-chlorine organic compound to form a hydrothermal oxidation system, wherein the addition amount of the fluorine-chlorine organic compound is 1-5 wt%; putting an electronic component into a hydrothermal oxidation system, wherein the mass ratio of the electronic component to the hydrothermal oxidation system is (0.1-1): 100, carrying out hydrothermal reaction; after cooling, the metal-containing solid residue is obtained by sieving with a sieve. According to the invention, the mixed acid generated in the hydrothermal treatment process of the fluorine-chlorine organic compound is adopted to remove the packaging material in the electronic element, so that the packaging material can be efficiently removed, and meanwhile, the fluorine-chlorine organic compound can be harmlessly treated, no additional acid is required to be added, energy is saved, emission is reduced, the environmental risk is reduced, and the method has the characteristics of low cost, high efficiency, low energy consumption and no pollution.
Description
Technical Field
The invention relates to the field of recycling of electronic components, in particular to a method for recycling metal resources in electronic components by using a fluorine-chlorine organic compound.
Background
The fluorine-chlorine organic compound has strong thermal stability, chemical stability, high surface activity, water and oil repellency due to C-F and C-Cl bonds contained in the fluorine-chlorine organic compound, and is widely applied. Common fluorine-containing compounds such as perfluoro compounds serve as fire extinguishing agents, cleaning agents in the electronic industry and the like, wherein perfluoro caprylic acid is the most common and widely applied. Fluorine-containing chlorine compounds, such as freon compounds, are commonly used as refrigerants for refrigerators and air conditioners. The overuse and improper disposal of fluorochloro organic compounds have potential effects on animal and human health, and their biological toxicity includes hepatotoxicity, cardiovascular toxicity, reproductive development toxicity, etc., and may even induce canceration of human organs.
Electronic waste is one of the fastest growing waste categories in the world at present, and the growth speed of electronic waste is ranked first among various waste categories. The electronic waste is composed of electronic components and corresponding packaging materials, wherein the metal accounts for about 60%, the packaging materials account for about 15%, the packaging materials mainly comprise resin and filling agents, the resin mainly comprises epoxy resin or phenolic resin, and the filling agents mainly comprise silicon dioxide micro powder or titanium dioxide micro powder.
The first problem of recycling metal resources in electronic components is to solve the problem of packaging materials for electronic components. The method can realize the recycling of metal resources contained in the electronic components while removing the electronic component packaging material. Therefore, the removal of the packaging material of the electronic component is the premise of realizing the resource utilization of the electronic component. At present, most of electronic garbage is roughly subjected to manual disassembly and acid leaching to extract metals such as copper, iron and the like, and then is incinerated and finally buried. This extensive recovery presents a very serious hazard to the local environment and to human health. For example, in the burning process, the resin in the packaging material can form dioxin, and has great toxicity.
Disclosure of Invention
The invention provides a method for recycling metal resources in electronic components by using a fluorine-chlorine organic compound, which aims to improve the resource utilization rate of electronic wastes, reduce the generation of dioxin in the treatment process, simultaneously carry out harmless treatment on the fluorine-chlorine organic compound, save energy, reduce emission and reduce the harm of pollutants to the environment.
In order to solve the above technical problems, the present invention provides a method for recovering metal resources in an electronic component using a chlorofluoro organic compound, comprising the steps of:
(1) uniformly mixing water, an oxidant and a fluorine-chlorine organic compound to form a hydrothermal oxidation system, wherein the addition amount of the fluorine-chlorine organic compound is 1-5 wt%;
(2) putting an electronic component into a hydrothermal oxidation system, wherein the mass ratio of the electronic component to the hydrothermal oxidation system is (0.1-1): 100, carrying out hydrothermal reaction;
(3) cooling the thermal degradation reactant, and then screening by using a screen to obtain a metal-containing solid residue after hydrothermal treatment;
the electronic component contains a packaging material made of resin-silicon dioxide, resin-titanium dioxide and resin-silicon dioxide-titanium dioxide, wherein the resin is epoxy resin or phenolic resin.
Preferably, in the step (1), the chlorofluoro organic compound is a freon or a perfluoro compound.
Preferably, the freon substances are selected from one or more of CFCs, HCFCs, HFCs and PFCs, and the perfluorinated compounds are selected from one or more of carbon tetrafluoride, hexafluoroethylene and perfluorooctanoic acid.
Preferably, in the step (1), the oxidant is one or more of hydrogen peroxide, ozone, oxygen and air.
Preferably, the oxidant is hydrogen peroxide, and the addition amount of the hydrogen peroxide is 3 wt% -10 wt%.
Preferably, in step (1), the water is ultrapure water, tap water, deionized water or groundwater.
Preferably, in the step (2), the hydrothermal reaction conditions are: the reaction temperature is 200-450 ℃, the reaction time is 10-100 min, and the stirring speed is 300-1000 r/min.
Preferably, in the step (3), the mesh number of the screen is 20-200 meshes.
Preferably, the electronic components are waste electronic components.
Compared with the prior art, the embodiment of the invention has the following beneficial effects:
1. according to the application, a hydrothermal method is adopted for reaction in a closed environment, clean raw material water is used as a reaction medium, waste electronic components and a fluorine-chlorine organic compound are combined, and the hydrothermal method is used for synergistic treatment. The organic fluorine and the organic chlorine in the fluorine-chlorine organic compound are ionized and converted into inorganic corrosive hydrochloric acid and hydrofluoric acid, and the inorganic corrosive hydrochloric acid and the inorganic corrosive hydrofluoric acid can react with silicon dioxide or titanium dioxide in the packaging material, so that the structure of the packaging material is damaged. The high-temperature and high-pressure water of the hydrothermal method can also remove the organic resin in the packaging material, so that the packaging material in the electronic component can be efficiently removed. And then, screening to obtain solid residues which are mainly metal gold, silver, copper, nickel, iron and the like in the electronic components, wherein the removal rate of the packaging material is more than 95 percent, and the metal recovery rate is more than 96 percent.
2. According to the invention, the mixed acid generated in the hydrothermal treatment process of the fluorine-chlorine organic compound is adopted to remove the packaging material in the electronic element, so that the fluorine-chlorine organic compound can be treated harmlessly, no additional acid is required to be added in the preparation process, and the environmental risk is reduced; meanwhile, the reaction is carried out in the closed environment of the reaction kettle, so that the risk of atmospheric pollution in the reaction process can be avoided, the method has the characteristics of low cost, high efficiency, low energy consumption and no pollution, and compared with the traditional electronic waste recycling method, the recovery method disclosed by the invention has obvious advantages in the aspects of energy conservation, emission reduction and environmental pollution reduction.
Drawings
FIG. 1: the invention relates to a method for recovering metal resources in electronic components by using a fluorine-chlorine organic compound, all raw materials, intermediate products and recovered metals.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the process of recycling the organic fluorine-chlorine compound, organic fluorine-chlorine can be converted into inorganic corrosive hydrochloric acid and hydrofluoric acid. The combination of hydrofluoric acid and hydrochloric acid is more corrosive to silicon dioxide or titanium dioxide than the acid alone. The principle is that some oxides, such as CaO, MgO or Al 2 O 3 Production of insoluble products such as CaF in HF solution 2 、MgF 2 、AlF 3 The insoluble substances can form an insoluble coating on the surface of the extract, thereby influencing the corrosion of the acid on the silicon dioxide or the titanium dioxide in the packaging material. Upon addition of HCl, insoluble material will be converted to soluble salts. CaF 2 →CaCl 2 ,MgF 2 →MgCl 2 ,AlF 3 →AlCl 3 . Therefore, the HF/HCl solution is more efficient than a single HF leach.
Therefore, the HF/HCl solution generated in the degradation process of the fluorine-chlorine organic compound is adopted, and simultaneously, the gas or liquid oxidant is matched, the gas oxidant is injected into the reaction kettle in a pressurizing mode, the packaging material for electronic elements in the electronic waste can be efficiently removed, the packaging material is made of resin-silicon dioxide, resin-titanium dioxide and resin-silicon dioxide-titanium dioxide, wherein the resin is epoxy resin or phenolic resin, and the electronic elements are recycled.
Example one
A method for recovering metal resources in electronic components by using a fluorine-chlorine organic compound comprises the following steps:
(1) adding about 300ml of deionized water into the inner liner of the reaction kettle, adding 3 wt% of hydrogen peroxide, adding 3g of trichlorofluoromethane, stirring for about 10min, and uniformly mixing to form a hydrothermal oxidation system;
(2) putting 0.8g of waste electronic components into a hydrothermal oxidation system, turning the lining into a reaction kettle, covering an upper cover of the reaction kettle, sealing the reaction kettle by an upper flange, and bearing the pressure of 40 Mpa;
(3) opening a switch of the reaction kettle, setting corresponding parameters of the reaction kettle such as hydrothermal temperature, reaction time and mechanical stirring speed, opening a heating switch of the reaction kettle, starting a temperature control program of the reaction kettle to work, heating and stirring for 20min at the temperature of 240 ℃, and rotating at the speed of 500 r/min;
(4) and (3) heating the reaction kettle according to a set program, cooling the reaction kettle to room temperature under natural conditions until the program is finished, opening the reaction kettle, taking out the lining, efficiently removing the packaging material of the electronic waste, and screening the hydrothermal solution by using a screen (80 meshes) to obtain metal-containing solid residues after hydrothermal treatment, wherein the metal-containing solid residues are mainly metals in the electronic waste, such as gold, silver, copper, nickel, iron and the like.
Example two
A method for recovering metal resources in electronic components by using a fluorine-chlorine organic compound comprises the following steps:
(1) adding 300ml of deionized water into the inner liner of the reaction kettle, adding 5 wt% of hydrogen peroxide, adding 5g of difluorodichloromethane, stirring for 10min, and uniformly mixing to form a hydrothermal oxidation system;
(2) putting 0.8g of waste electronic components into a hydrothermal oxidation system, turning the lining into a reaction kettle, covering an upper cover of the reaction kettle, sealing the reaction kettle by an upper flange, and bearing the pressure of 40 Mpa;
(3) opening a switch of the reaction kettle, setting corresponding parameters of the reaction kettle such as hydrothermal temperature, reaction time and mechanical stirring speed, opening a heating switch of the reaction kettle, starting a temperature control program of the reaction kettle to work, heating and stirring for 30min at the temperature of 280 ℃, and rotating speed of 800 r/min;
(4) and (3) heating the reaction kettle according to a set program, cooling the reaction kettle to room temperature under natural conditions until the program is finished, opening the reaction kettle, taking out the lining, efficiently removing the packaging material of the electronic waste, and screening the hydrothermal solution by using a screen (100 meshes) to obtain metal-containing solid residues after hydrothermal treatment, wherein the metal-containing solid residues mainly comprise metals such as gold, silver, copper, nickel, iron and the like in the electronic waste.
EXAMPLE III
A method for recovering metal resources in electronic components by using a fluorine-chlorine organic compound comprises the following steps:
(1) adding about 300ml of deionized water into the inner liner of the reaction kettle, adding 7 wt% of hydrogen peroxide, adding 2g of perfluorooctanoic acid, stirring for about 10min, and uniformly mixing to form a hydrothermal oxidation system;
(2) putting 0.8g of waste electronic components into a hydrothermal oxidation system, turning the lining into a reaction kettle, covering an upper cover of the reaction kettle, sealing the reaction kettle by an upper flange, and bearing the pressure of 40 Mpa;
(3) opening a switch of the reaction kettle, setting corresponding parameters of the reaction kettle such as hydrothermal temperature, reaction time and mechanical stirring speed, opening a heating switch of the reaction kettle, starting a temperature control program of the reaction kettle to work, heating and stirring for 10min at the temperature of 350 ℃, and rotating at the speed of 900 r/min;
(4) and (3) heating the reaction kettle according to a set program, cooling the reaction kettle to room temperature under natural conditions until the program is finished, opening the reaction kettle, taking out the lining, efficiently removing the packaging material of the electronic waste, and screening the hydrothermal solution by using a screen (100 meshes) to obtain metal-containing solid residues after hydrothermal treatment, wherein the metal-containing solid residues are mainly metals in the electronic waste, such as gold, silver, copper, nickel, iron and the like.
Example four
A method for recovering metal resources in electronic components by using fluorine-chlorine organic compounds is characterized in that the steps, reagents used in the steps and process parameters are the same as those in the first embodiment, and the difference is that in the step (1), hydrogen peroxide is replaced by oxygen, and oxygen is introduced into a reaction kettle until the pressure representation number of the reaction kettle is 0.01 Mpa.
Comparative example 1
The method for recovering metal resources in electronic components and parts has the same steps, reagents used in the steps and process parameters as those in the first embodiment, and is different in that in the step (1), the addition amount of trichlorofluoromethane is 0.
Performance test
1. The method for calculating the removal rate of the packaging material of the waste electronic components in the embodiments 1 to 4 and the comparative example 1 is as follows: respectively weighing the mass M of the electronic waste solid before and after treatment by adopting a weight difference method 1 ，M 2 Then, the formula of the removal rate R of the encapsulation material is expressed as formula 1:
2. the metal recovery rate calculation method of the waste electronic components in the examples 1 to 4 and the comparative example 1 is as follows: respectively measuring the metal content Q in the electronic waste raw material by adopting high-resolution inductively coupled plasma mass spectrometry (ICP-MS) 1 And the content Q of metal ions in the hydrothermal solution after the reaction 2 Then, the formula of the metal recovery rate Q is expressed by the following formula 2:
table 1-removal rate of encapsulating material and recovery rate of metal of used electronic components in examples 1 to 4 and comparative example 1
| Detecting items | Encapsulation material removal (%) | Recovery of Metal (%) |
| Example 1 | 97.8 | 98.7 |
| Example 2 | 99.3 | 98.4 |
| Example 3 | 99.9 | 98.5 |
| Example 4 | 97.8 | 96.3 |
| Comparative example 1 | 67.7％ | 94.5％ |
Comparative example 1 when the removal rate of the encapsulating material is greater than 65%, a higher metal recovery rate can be achieved, at this time, the physical and chemical properties of the encapsulating material have been changed, the hard and tightly sealed encapsulating material has become loose and brittle, and the remaining damaged encapsulating material can be washed away by the scouring action of water flow in the subsequent screening and scouring process. However, in this case, a small amount of package residue remains on the surface of the recovered metal, which affects the recovery purity of the metal and lowers the purity of the recovered metal.
The embodiment of the application has higher removal rate of the packaging material, and when the removal rate of the packaging material is more than 93%, the residual packaging material can be separated from the metal in the waste. I.e., the higher the removal rate of the encapsulating material, the more convenient the subsequent metal recovery process, and the higher the purity of the recovered metal.
The above-mentioned embodiments are provided to further explain the objects, technical solutions and advantages of the present invention in detail, and it should be understood that the above-mentioned embodiments are only examples of the present invention and are not intended to limit the scope of the present invention. It should be understood that any modifications, equivalents, improvements and the like, which come within the spirit and principle of the invention, may occur to those skilled in the art and are intended to be included within the scope of the invention.
Claims (8)
1. A method for recovering metal resources in electronic components by using a fluorine-chlorine organic compound is characterized by comprising the following steps:
(1) uniformly mixing deionized water, an oxidant and a fluorine-chlorine organic compound to form a hydrothermal oxidation system, wherein the addition amount of the fluorine-chlorine organic compound is 1-5 wt%;
(2) putting an electronic component into a hydrothermal oxidation system, wherein the mass ratio of the electronic component to the hydrothermal oxidation system is (0.1-1): 100, carrying out hydrothermal reaction;
(3) after the hydrothermal reaction product is cooled, screening and filtering by using a screen mesh to obtain a metal-containing solid residue after hydrothermal treatment;
the electronic component contains a packaging material made of resin-silicon dioxide, resin-titanium dioxide and resin-silicon dioxide-titanium dioxide, wherein the resin is epoxy resin or phenolic resin.
2. The method for recovering metal resources in electronic components using a chlorofluoro organic compound as claimed in claim 1, wherein in the step (1), said chlorofluoro organic compound is a chlorofluorocarbon or perfluorocompound.
3. The method of claim 2, wherein the freon is selected from one or more of CFCs, HCFCs, HFCs and PFCs, and the perfluoro compound is selected from one or more of tetrafluoromethane, hexafluoroethylene and perfluorooctanoic acid.
4. The method for recovering metal resources in electronic components using a chlorofluoro organic compound as claimed in claim 1, wherein in step (1), the oxidizing agent is any one selected from hydrogen peroxide, ozone, oxygen and air.
5. The method for recovering metal resources in electronic components by using the fluorine-chlorine organic compound as claimed in claim 4, wherein the oxidant is hydrogen peroxide, and the addition amount of the hydrogen peroxide is 3 wt% -10 wt%.
6. The recycling method for removing the electronic component packaging material by using the fluorochloro organic compound as set forth in claim 1, wherein in the step (2), the hydrothermal reaction conditions are as follows: the reaction temperature is 200-450 ℃, the reaction time is 10-100 min, and the stirring speed is 300-1000 r/min.
7. The recycling method for removing electronic component packaging material using a chlorofluoro organic compound as claimed in claim 1, wherein in the step (3), the mesh number of the screen is 20 to 200 mesh.
8. The recycling method for removing the electronic component packaging material by using the fluorochloro organic compound as recited in claim 1, wherein the electronic component is a waste electronic component.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103058190A (en) * | 2011-10-20 | 2013-04-24 | 同济大学 | Harmlessness treatment method for freon |
| CN104386650A (en) * | 2014-10-02 | 2015-03-04 | 董亚伦 | Treatment process for waste freon |
| CN112280986A (en) * | 2020-10-22 | 2021-01-29 | 上海交通大学 | Method for leaching gallium and arsenic from waste gallium arsenide-containing LED electronic devices and simultaneously recovering metallic silver and application |
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- 2022-06-24 CN CN202210723985.5A patent/CN115094231A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103058190A (en) * | 2011-10-20 | 2013-04-24 | 同济大学 | Harmlessness treatment method for freon |
| CN104386650A (en) * | 2014-10-02 | 2015-03-04 | 董亚伦 | Treatment process for waste freon |
| CN112280986A (en) * | 2020-10-22 | 2021-01-29 | 上海交通大学 | Method for leaching gallium and arsenic from waste gallium arsenide-containing LED electronic devices and simultaneously recovering metallic silver and application |
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