Method for treating waste catalyst containing copper and zinc

Abstract

The invention discloses a method for treating a waste catalyst containing copper and zinc. The method comprises the following steps: calculating the material dosage according to the waste catalyst, mixing the materials, heating and melting, and collecting metal copper and zinc. According to the method, the sulfur component in the waste catalyst can be removed through the slag regulator in the treatment process, and the purity of a copper ingot is increased; the carbon deposit is used as a reducing agent, so that the carbon deposit in the waste catalyst is reasonably utilized; the method has the advantages of simple process, environment friendliness and high metal recovery rate.

Description

Technical Field

[0001] The present invention relates to the technical field of waste catalyst disposal, and more particularly to a method for disposing waste catalyst containing copper and zinc. Background Art

[0002] Copper-zinc catalysts are mainly used to prepare methanol, which is an important basic chemical raw material and plays a vital role in the new energy strategy. With the rapid development of industry, the use of copper-zinc catalysts is relatively large, but due to the poor heat resistance, sulfur resistance, and moisture absorption of copper-zinc catalysts, their activity decreases rapidly during the use process of heating, pulverization, and carbon deposition, and they become waste catalysts. Copper-zinc catalysts are mainly composed of copper and zinc oxides, and the metal copper and zinc in them have important utilization value. Recycling the metal resources in such waste catalysts can not only turn waste into treasure, but also be beneficial to environmental protection.

[0003] At present, the main disposal methods for waste catalysts containing copper and zinc include landfill, wet method, pyrolysis and dry-wet combined method. Landfill not only wastes a lot of valuable metal resources, but also pollutes the environment. The wet disposal method refers to the use of acid, alkali or other solutions to separate the valuable components in the waste catalyst, and use extraction and other impurity removal and passivation, and then recover the valuable metals in the waste catalyst through processes such as electrolytic deposition. The wet disposal is not only complex in process and low in recovery rate, but also produces a large amount of waste liquid, causing secondary pollution. At the same time, it is impossible to effectively dispose of waste catalysts with carbon deposition. The pyrolysis disposal mainly involves high-temperature roasting of the waste catalyst in a kiln. The current metal recovery rate of the existing pyrolysis disposal is not high, and it cannot remove or reduce the sulfur component in the waste catalyst, and it is easy to form a large amount of copper sulfur, which requires secondary treatment. The dry-wet combined method is to dispose of the waste catalyst by high-temperature calcination combined with solution leaching. The final product is copper oxide and zinc oxide. This method also has the problem of producing waste liquid and ammonia, causing environmental pollution.

[0004] Therefore, there is an urgent need for a method for disposing of copper-zinc-containing waste catalysts. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for disposing waste catalysts containing copper and zinc, so as to solve the problems in the background technology.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows.

[0007] A method for disposing waste catalyst containing copper and zinc, comprising the following steps:

[0008] S1: According to the amount of copper-zinc waste catalyst m 1 , calculate the required amount of reducing agent m 2 And the amount of slag regulator m 3 ;

[0009] S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator and add them into the disposal furnace, turn on the power and raise the temperature to 1400℃~1600℃, and use the pyroelectric reduction process to melt the materials in the disposal furnace and react;

[0010] S3: The copper solution formed by the reduction of copper oxide in the copper-zinc-containing waste catalyst is received at the copper outlet of the disposal furnace, and the molten copper is poured into a mold after being discharged from the furnace. After being cooled and demolded, a black copper (or crude copper) product is obtained; the slag floating on the top of the molten copper is received into a slag pit or a slag mold at the slag outlet of the disposal furnace; the metallic zinc obtained by reducing zinc oxide in the copper-zinc-containing waste catalyst and evaporated into zinc vapor due to high temperature is recovered from the dust removal system of the disposal furnace.

[0011] To further optimize the technical solution, the reducing agent is a carbonaceous reducing agent, and the carbonaceous reducing agent is one or more of coke, lignite, and petroleum coke.

[0012] Further optimizing the technical solution, the mass ratio of the copper-zinc waste catalyst to the carbonaceous reducing agent is m 1 :m 2 =100:(5~15).

[0013] Further optimizing the technical solution, the dosage ratio of the copper-zinc waste catalyst and the slag regulator is m 1 :m 3 =100:(20-40) and the slag regulator is a mixture of silica, lime or limestone in proportion, or the slag regulator is a mixture of silica, lime or limestone and dolomite in proportion.

[0014] Further optimizing the technical solution, the slag regulator is silica mass m 31 : Lime mass m 32 =100: (110-150) mass of mixture or silica m 31 : Lime mass m 32 :Dolomite mass m 33 =100:(50~100):(150~200) mixture.

[0015] To further optimize the technical solution, the treatment furnace is one of a high-frequency induction furnace, a mineral heat electric furnace, and an electric arc furnace.

[0016] Due to the adoption of the above technical scheme, the technical progress achieved by the present invention is as follows.

[0017] The present invention provides a method for treating waste catalysts containing copper and zinc. The treatment process is a pyroelectric reduction process. The treatment furnace used is an electric furnace, and the temperature in the furnace is controllable. The sulfur component in the waste catalyst is removed by adding lime / limestone in the slag regulator to avoid or reduce the formation of copper and sulfur, thereby improving the purity of the product. At the same time, the carbon deposits in the waste catalyst can be effectively utilized as part of the carbonaceous reducing agent, thus turning waste into treasure. The present invention has the advantages of simple process, environmental friendliness, and high metal recovery rate. DETAILED DESCRIPTION

[0018] A method for disposing waste catalyst containing copper and zinc, comprising the following steps:

[0019] S1: According to the amount of copper-zinc waste catalyst m 1 , calculate the required amount of reducing agent m 2 And the amount of slag regulator m 3 .

[0020] The main components of copper-zinc waste catalyst include 30% to 55% CuO, 20% to 45% ZnO, ≤15% Al 2 O 3 ; ≤5% C; ≤5% S.

[0021] The reducing agent is a carbonaceous reducing agent, and its main function is to reduce the copper oxide and zinc oxide in the copper-zinc waste catalyst. The method for calculating the amount of reducing agent is mainly based on the carbon thermal reduction reaction to calculate the method for determining the amount of carbonaceous reducing agent:

[0022] The carbothermal reduction reaction has the following reactions:

[0023] CuO+C=Cu+CO

[0024] ZnO+C=Zn+CO

[0025] The carbonaceous reducing agent is one or more of coke, blue coke, and petroleum coke, and the carbon deposits in the copper-zinc waste catalyst are also used as a reducing agent. The mass ratio of the copper-zinc waste catalyst to the carbonaceous reducing agent is m 1 :m 2 =100:(5~15).

[0026] The dosage ratio of copper-zinc waste catalyst to slag regulator is m 1 :m 3 =100: (20-40), its main functions are: first, the SO generated by the combustion of lime / limestone in the slag regulator and S in the spent catalyst 2The reaction generates calcium sulfate, removes the sulfur component in the copper-zinc waste catalyst, avoids or reduces the formation of cuprous sulfide, and improves the purity of the product. The copper liquid obtained after high-temperature reduction treatment is cast into copper ingots, which can fully meet the requirements of the "Black Copper" (YS / T632-2020) standard and even meet the "Crude Copper" (YS / T-2015) standard. The copper ingots can be sold as products without secondary treatment; secondly, it can be combined with aluminum oxides in the copper-zinc waste catalyst to form a low-melting-point slag, which can effectively promote the separation of slag and gold, promote the reduction of copper-zinc oxides in the waste catalyst to metallic copper and zinc, and improve the metal recovery rate of copper-zinc waste catalysts.

[0027] The slag regulator is a mixture of silica, lime or limestone in proportion. The amount of slag regulator is mainly determined according to the content of aluminum oxide in the copper-zinc waste catalyst, so that the pH value of the generated slag is suitable for disposal needs. 2 O 3 -CaO-SiO 2 ) or quaternary slag system (Al 2 O 3 -CaO-SiO 2 -MgO) slag has high basicity and good desulfurization effect, but the melting temperature will be correspondingly high. In order to achieve a better desulfurization effect and keep a relatively low slag melting temperature, the binary basicity of the slag (R = CaO / SiO2) needs to be controlled between 1.1-1.4. The specific ratio is: silica mass m 31 : Lime mass m 32 =100:(110~150). The slag regulator can also be a mixture of silica, lime or limestone and dolomite in proportion, the specific proportion is: silica mass m 31 : Lime mass m 32 :Dolomite mass m 33 =100:(50~100):(150~200).

[0028] S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator and add them into a treatment furnace, which is one of a frequency induction furnace, a mineral heat electric furnace and an electric arc furnace.

[0029] When the furnace volume is limited, adding materials in batches can obtain a larger disposal volume and improve the utilization rate of the electric furnace. Then the temperature is raised to 1400℃~1600℃, and the pyroelectric reduction process is used to melt the materials in the disposal furnace and react.

[0030] S3: The copper solution formed by the reduction of copper oxide in the copper-zinc waste catalyst is received at the copper outlet of the disposal furnace. The copper melt is poured into a mold after being discharged from the furnace. After cooling and demolding, a black copper (or crude copper) product is obtained. The slag floating on the copper melt is received into a slag pit or slag mold at the slag outlet of the disposal furnace, which can be used as a building material. The metal zinc obtained by reducing zinc oxide in the copper-zinc waste catalyst and evaporating into zinc vapor due to high temperature is recovered from the dust removal system of the disposal furnace. The zinc vapor is oxidized into zinc oxide in the air, which is recovered by the flue gas dust removal system of the disposal furnace and sold as a product.

[0031] The present invention will be further described in detail below with reference to specific embodiments.

[0032] Embodiment 1:

[0033] S1: According to the amount of copper-zinc waste catalyst m 1 , calculate the required amount of reducing agent m 2 And the amount of slag regulator m 3 .

[0034] The method for treating the copper-zinc waste catalyst provided in this embodiment is carried out in a medium frequency induction furnace. The treated copper-zinc waste catalyst includes: CuO = 48.5%; ZnO = 32.8%; Al 2 O 3 =10.6%; C = 3.5%; S = 3.2%. The selected carbonaceous reducing agent is coke with a fixed carbon content of 88%, and the selected slag regulator is lime (CaO = 99.5%) and silica (SiO 2 =98.5%).

[0035] After calculation, the amount of each material in the batch is: 100g of copper-zinc waste catalyst, 10g of coke, 10.4g of lime, and 8.6g of silica. A total of 3 batches are prepared, with a total amount of 387g.

[0036] S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator, add them into the medium frequency induction furnace in 3 batches, turn on the power and heat it to 1400℃, keep it at this temperature for 10-20 minutes to ensure complete reaction of the materials.

[0037] S3: pouring with slag out of the furnace; demoulding after the ingot mold is cooled, slag and gold are separated to obtain a copper ingot. Since this embodiment is carried out in a laboratory, no zinc oxide recovery device is set up, so the obtained zinc oxide is extracted through the exhaust system, and the obtained copper ingot weighs 35.5g. After analysis, the contents of the main metal components are: Cu = 97.9%, Zn = 0.9%, Fe = 0.8%, Al = 0.02%, S = 0.005%, C = 0.02%.

[0038] Embodiment 2:

[0039] S1: According to the amount of copper-zinc waste catalyst m 1 , calculate the required amount of reducing agent m 2 And the amount of slag regulator m 3 .

[0040] The method for treating the copper-zinc waste catalyst provided in this embodiment is carried out in a medium frequency induction furnace. The treated copper-zinc waste catalyst includes: CuO = 44.0%; ZnO = 42%; Al 2 O 3 =8.6%; C = 2.5%; S = 3.8%. The selected carbonaceous reducing agent is blue coke, with a fixed carbon content of 88%, and the selected slag regulators are lime (CaO = 56%) and silica (SiO 2 =98.5%).

[0041] After calculation, the amount of each material in the batch is: 100g of copper-zinc waste catalyst, 12g of lignite, 15.4g of lime, and 8.6g of silica. A total of 3 batches are prepared, with a total amount of 408.

[0042] S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator, add them into the medium frequency induction furnace in 3 batches, turn on the power and heat it to 1500℃, keep it at this temperature for 10-20 minutes to ensure complete reaction of the materials.

[0043] S3: pouring with slag out of the furnace; demoulding after the ingot mold is cooled, slag and gold are separated to obtain a copper ingot. Since this embodiment is carried out in a laboratory, no zinc oxide recovery device is set up, so the obtained zinc oxide is extracted through the exhaust system, and the obtained copper ingot weighs 34g. After analysis, the contents of the main metal components are: Cu = 95.9%, Zn = 1.0%, Fe = 0.9%, Al = 0.05%, S = 0.005%, C = 0.03%.

[0044] Embodiment 3:

[0045] S1: According to the amount of copper-zinc waste catalyst m 1 , calculate the required amount of reducing agent m 2 And the amount of slag regulator m 3 .

[0046] The method for treating the copper-zinc waste catalyst provided in this embodiment is carried out in a medium frequency induction furnace. The treated copper-zinc waste catalyst includes: CuO = 30.5%; ZnO = 20.8%; Al 2 O 3 =14.6%; C = 1.5%; S = 2.5%. The selected carbonaceous reducing agent is coke with a fixed carbon content of 88%, and the selected slag regulator is lime (CaO = 75.5%) and silica (SiO 2 =90.5%).

[0047] After calculation, the amount of each material in the batch is: 100g of copper-zinc waste catalyst, 11g of coke, 9.2g of lime, and 7.6g of silica. A total of 3 batches are prepared, with a total amount of 383.4g.

[0048] S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator, add them into the medium frequency induction furnace in 3 batches, turn on the power and heat it to 1400℃, keep it at this temperature for 10-20 minutes to ensure complete reaction of the materials.

[0049] S3: pouring with slag out of the furnace; demoulding after the ingot mold is cooled, slag and gold are separated to obtain a copper ingot. Since this embodiment is carried out in a laboratory, no zinc oxide recovery device is set up, so the obtained zinc oxide is extracted through the exhaust system, and the obtained copper ingot weighs 35.5g. After analysis, the contents of the main metal components are: Cu = 96.7%, Zn = 0.88%, Fe = 0.82%, Al = 0.02%, S = 0.005%, C = 0.02%.

[0050] According to the experimental data of Examples 1-3, the method for treating waste catalyst containing copper and zinc of the present invention is simple in process, can use the carbon deposits in the waste catalyst as a reducing agent, and has a high metal recovery rate.

Claims

1. A method for treating waste catalyst containing copper and zinc, characterized in that: The specific steps include: S1: Calculate the required amount of reducing agent m2 and slag regulator m3 according to the amount of copper-zinc waste catalyst m1; S2: Mix the prepared copper-zinc-containing waste catalyst, reducing agent and slag regulator and add them into the disposal furnace, turn on the power and raise the temperature to 1400℃~1600℃, and use the pyroelectric reduction process to melt the materials in the disposal furnace and react; S3: The copper solution formed by the reduction of copper oxide in the copper-zinc-containing waste catalyst is received at the copper outlet of the disposal furnace, and the molten copper is poured into a mold after being discharged from the furnace. After being cooled and demolded, a black copper (or crude copper) product is obtained; the slag floating on the top of the molten copper is received into a slag pit or a slag mold at the slag outlet of the disposal furnace; the metallic zinc obtained by reducing zinc oxide in the copper-zinc-containing waste catalyst and evaporated into zinc vapor due to high temperature is recovered from the dust removal system of the disposal furnace.

2. The method for disposing waste catalyst containing copper and zinc according to claim 1, characterized in that: The reducing agent is a carbonaceous reducing agent, and the carbonaceous reducing agent is one or more of coke, blue coke, and petroleum coke.

3. The method for disposing waste catalyst containing copper and zinc according to claim 2, characterized in that: The mass ratio of the copper-zinc-containing waste catalyst to the carbonaceous reducing agent is m1:m2=100:(5-15).

4. A method for disposing of waste catalyst containing copper and zinc according to claim 3, characterized in that: The dosage ratio of the copper-zinc-containing waste catalyst and the slag regulator is m1:m3=100:(20-40), and the slag regulator is a mixture of silica, lime or limestone in proportion, or the slag regulator is a mixture of silica, lime or limestone and dolomite in proportion.

5. The method for disposing waste catalyst containing copper and zinc according to claim 4, characterized in that: The slag regulator is silica mass m 31 : Lime mass m 32 =100: (110-150) mass of mixture or silica m 31 : Lime mass m 32 :Dolomite mass m 33 =100:(50~100):(150~200) mixture.

6. The method for disposing waste catalyst containing copper and zinc according to claim 1, characterized in that: The treatment furnace is one of a high-frequency induction furnace, a mineral-heat electric furnace, and an electric arc furnace.