The invention belongs to the technical field of hydrometallurgical electrowinning, and specifically relates to a method for preparing a titanium coated anode.
Titanium coated anode –Background technique:
In various electrowinning fields such as zinc electrowinning and copper electrowinning, the electrolyte composition is h2so4+meso4, and the impurity of the electrowinning needs to be controlled within a certain range so as not to affect the electrowinning. The metal lead forms a protective film on the surface of the sulfuric acid solution. It can prevent further corrosion, so lead is widely used in hydrometallurgical industries such as zinc electrowinning and copper electrowinning as an insoluble anode. However, lead as an anode material has the following problems:
1) Lead has low rigidity and strength, which is easy to deform during use, causing short circuit between cathode and anode, affecting production;
2) If the concentration of cl ions in the electrolyte is too high, lead corrosion resistance is poor and lead is rapid Dissolution, on the one hand, the lead anode has a short service life, on the other hand, the dissolved lead precipitates on the cathode to contaminate the metal deposited on the cathode;
3) the lead conductivity is poor, the lead anode has a high overpotential for oxygen evolution, and the cell voltage is high during the electrowinning process. High DC power consumption. In order to solve the problems in the lead anode electrowinning process, noble metal silver is generally added in the industry, but the amount of addition is large, resulting in high production and use costs of lead anodes.
Titanium metal has good conductivity, corrosion resistance, strength and rigidity. If titanium is used directly as the anode for electrowinning, the surface of the titanium metal is easily oxidized to form tio2, which is not conductive, and the electrowinning cannot proceed normally. The cathode will not deposit metal. Less than expected.
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Technical realization elements:
In order to solve the above technical problems, the present invention provides a method for preparing a titanium coated anode. The coating material is coated on the surface of titanium, which solves the problems of non-conductivity after titanium oxidation, corrosion resistance of lead anode, and high direct current consumption. At the same time, the coating material has good conductivity, corrosion resistance and electrocatalysis, and the electrode material has a long service life, which effectively improves the quality of the metal deposited by the cathode.
In order to achieve the above objectives, the present invention is achieved through the following technical solutions:
The method for preparing the titanium coated anode includes the following steps:
1) Prepare a mixture of hydrated ircl3, tacl5 and concentrated hcl;
2) Use a degreasing agent to remove oil stains on the surface of the titanium plate, and clean and dry the degreasing titanium plate;
3) Evenly brush the hydrated ircl3, tacl5 and concentrated hcl mixture on the surface of the dried titanium plate, and then dry it;
4) Oxygen roasting treatment of the titanium plate after step 3) drying;
5) Take out the titanium plate baked in step 4) and cool it to room temperature;
6) Repeat steps 3)-5), painting the mixture of hydrated ircl3, tacl5 and concentrated hcl, drying, roasting and cooling, and circulate 3-4 times to obtain a titanium coated anode.
Further, in step 1), the chemical composition of hydrated ircl3 is ≥99.9%; the chemical composition of tacl5 is ≥99.8%; the chemical composition of concentrated hcl is ≥35%.
Furthermore, the mixture of hydrated ircl3, tacl5 and concentrated hcl has its chemical composition w(ircl3)=2-2.5%, w(tacl5)=3-3.5%, and the balance is concentrated hcl; it needs to be evenly painted when painting. The brushing time is 1-2min, and the brushing speed is 0.1-0.2m/s.
Further, in step 2), the chemical composition of the titanium plate is w(fe)≤0.2%, w(al)≤0.2%, w(si)≤0.08%, w(c)≤0.05%, w(n) ≤0.03%, w(h)≤0.003%, w(o)≤0.12%, w(other)≤0.1%, the balance is ti, the roughness of the titanium plate is ≥ra50.
Further, in step 2), the degreasing agent is a conventional industrial degreasing agent, the concentration of the degreasing agent is 2-3%, the degreasing temperature is 35-55°C, and the degreasing time is 5-10 min.
Further, in step 2), cleaning the titanium plate after degreasing means: placing the titanium plate in clean water and soaking at a temperature of 15-35° C. and a soaking time of 2-3 min.
Further, in step 2), the drying treatment adopts drying treatment, the temperature is 120-140°C, and the drying time is 5-10 min.
Further, in step 3), the drying treatment adopts drying treatment, the temperature is 110-120°C, and the drying time is 8-10 minutes.
Furthermore, in step 4), a muffle furnace is used for the roasting treatment, oxygen is passed through during roasting, the oxygen concentration is greater than 90%, the flow rate is 0.5-0.6 m3/h, the roasting temperature is 520-530°C, and the roasting time is 5-6h.
The beneficial effects of the present invention:
The invention coats the coating material on the surface of the titanium plate, and obtains the coated anode after drying and baking treatment, which can solve the short service life and cathode deposition of the electrode material in the hydrometallurgical electrowinning process such as zinc electrowinning and copper electrowinning. Technical issues such as low metal purity and high DC power consumption extend the service life of electrode materials, improve the quality of cathode deposited metal, and effectively increase the economic benefits of enterprises.
detailed description
In order to make the objectives, technical solutions and beneficial effects of the present invention clearer, the preferred embodiments of the present invention will be described in detail below to facilitate the understanding of the skilled person.
Example 1
The chemical components of the reagents and titanium plates used in this example are as follows:
The chemical composition of hydrated ircl3≥99.9%; the chemical composition of tacl5≥99.8%; the chemical composition of concentrated hcl≥35%. ta1 industrial titanium plate, its chemical composition is w(fe)≤0.2%, w(al)≤0.2%, w(si)≤0.08%, w(c)≤0.05%, w(n)≤0.03%, w (h)≤0.003%, w(o)≤0.12%, w(other)≤0.1%, the balance is ti, and the roughness of the titanium plate is ≥ra50.
The preparation of titanium coated anode includes the following steps:
1) Preparation of a mixture of hydrated ircl3, tacl5 and concentrated hcl: a mixture of hydrated ircl3, tacl5 and concentrated hcl, the chemical composition of which is w(ircl3)=2.5%, w(tacl5)=3%, and the balance is concentrated hcl.
2) Use an industrial degreasing agent to remove oil stains on the surface of the titanium plate. The concentration of the degreasing agent is 2%, the degreasing temperature is 35°C, and the degreasing time is 10 minutes, and it is cleaned with a manual rag. Clean the degreasing titanium plate: place the degreasing titanium plate in clean water and soak at a temperature of 15°C for 2 minutes. Take out the clean titanium plate after soaking and place it in an oven for drying at a drying temperature of 120°C and a drying time of 10 minutes.
3) Use a brush to evenly apply the mixture of hydrated ircl3, tacl5 and concentrated hcl on the surface of the dried titanium plate. The brushing time is 1min and the brushing speed is 0.2m/s; the finished titanium plate is placed in an oven to dry Dry, the drying temperature is 110℃, and the drying time is 10min.
4) The titanium plate after drying in step 3) is placed in a muffle furnace for oxygen roasting. During roasting, the oxygen concentration is greater than 90%, the flow rate is 0.5-0.6 m3/h, the roasting temperature is 520-530°C, and the roasting time is 6 hours.
5) Take out the titanium plate calcined in step 4) and place it in the air to cool to room temperature naturally.
6) Repeat steps 3)-5), apply the mixture of hydrated ircl3, tacl5 and concentrated hcl, dry and roast, and cycle 3 times to complete the preparation of the titanium coated anode.
Example 2
The chemical components of the reagents and titanium plates used in this example are as follows:
The chemical composition of hydrated ircl3≥99.9%; the chemical composition of tacl5≥99.8%; the chemical composition of concentrated hcl≥35%. ta1 industrial titanium plate, its chemical composition is w(fe)≤0.2%, w(al)≤0.2%, w(si)≤0.08%, w(c)≤0.05%, w(n)≤0.03%, w (h)≤0.003%, w(o)≤0.12%, w(other)≤0.1%, the balance is ti, and the roughness of the titanium plate is ≥ra50.
The preparation of titanium coated anode includes the following steps:
1) Preparation of a mixture of hydrated ircl3, tacl5 and concentrated hcl: a mixture of hydrated ircl3, tacl5 and concentrated hcl, the chemical composition of which is w(ircl3)=2.5%, w(tacl5)=3%, and the balance is concentrated hcl.
2) Use an industrial degreasing agent to remove oil stains on the surface of the titanium plate. The concentration of the degreasing agent is 3%, the degreasing temperature is 45°C, and the degreasing time is 8 minutes, and it is cleaned with a manual rag. Clean the degreasing titanium plate: place the degreasing titanium plate in clean water and soak at a temperature of 26°C for 2 minutes. Take out the clean titanium plate after soaking and place it in an oven for drying at a drying temperature of 130°C and a drying time of 8 minutes.
3) Use a brush to evenly brush the hydrated ircl3, tacl5 and concentrated hcl mixture on the surface of the dried titanium plate, the brushing time is 2min, the brushing speed is 0.1m/s; the finished titanium plate is placed in the oven to dry Dry, the drying temperature is 110℃, and the drying time is 10min.
4) Place the titanium plate after drying in step 3) in a muffle furnace and roast with oxygen. During roasting, the oxygen concentration is greater than 90%, the flow rate is 0.5-0.6m3/h, the roasting temperature is 520-530°C, and the roasting time is 5h.
5) Take out the titanium plate calcined in step 4) and place it in the air to cool to room temperature naturally.
6) Repeat steps 3)-5), paint the mixture of hydrated ircl3, tacl5 and concentrated hcl, dry and roast, and cycle 4 times to complete the preparation of the titanium coated anode.
Example 3
The chemical components of the reagents and titanium plates used in this example are as follows:
The chemical composition of hydrated ircl3≥99.9%; the chemical composition of tacl5≥99.8%; the chemical composition of concentrated hcl≥35%. ta1 industrial titanium plate, its chemical composition is w(fe)≤0.2%, w(al)≤0.2%, w(si)≤0.08%, w(c)≤0.05%, w(n)≤0.03%, w (h)≤0.003%, w(o)≤0.12%, w(other)≤0.1%, the balance is ti, and the roughness of the titanium plate is ≥ra50.
The preparation of titanium coated anode includes the following steps:
1) Preparation of a mixture of hydrated ircl3, tacl5 and concentrated hcl: a mixture of hydrated ircl3, tacl5 and concentrated hcl, the chemical composition of which is w(ircl3)=2%, w(tacl5)=3.5%, and the balance is concentrated hcl.
2) Use an industrial degreasing agent to remove oil stains on the surface of the titanium plate. The concentration of the degreasing agent is 3%, the degreasing temperature is 55°C, and the degreasing time is 5 minutes, and it is cleaned with a manual rag. Clean the degreasing titanium plate: place the degreasing titanium plate in clean water and soak at a temperature of 35°C and soak for 3 minutes. Take out the clean titanium plate after soaking and place it in an oven for drying at a drying temperature of 140°C and a drying time of 5 minutes.
3) Use a brush to evenly brush the hydrated ircl3, tacl5 and concentrated hcl mixture on the surface of the dried titanium plate, the brushing time is 2min, the brushing speed is 0.1m/s; the finished titanium plate is placed in the oven to dry Dry, drying temperature 120℃, drying time 8min.
4) Place the titanium plate after drying in step 3) in a muffle furnace and roast with oxygen. During roasting, the oxygen concentration is greater than 90%, the flow rate is 0.5-0.6m3/h, the roasting temperature is 520-530°C, and the roasting time is 5h.
5) Take out the titanium plate calcined in step 4) and place it in the air to cool to room temperature naturally.
6) Repeat steps 3)-5), paint the mixture of hydrated ircl3, tacl5 and concentrated hcl, dry and roast, and cycle 4 times to complete the preparation of the titanium coated anode.
The titanium-coated anodes prepared in Examples 1-3 were subjected to an electrowinning test and compared with the traditional lead-silver binary alloy for zinc electrowinning. The test process conditions are as follows.
h2so4 mass concentration: 145～155g/l, znso4 mass concentration: 45～0g/l, electrolyte temperature: 37-42℃, current density: 400-420a/m2, electrowinning cycle: 24h. After 30 cycles (a total of 720h) electrowinning test, the test data is as follows:
Remarks: The service life of lead-silver anodes is calculated based on the total anode weight and anode residual value weight and anode weight reduction rate. Titanium-coated anode service life is calculated based on the total coating weight and coating residual value weight and anode weight reduction rate.
Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that it can be combined in form and Various changes are made to the details without departing from the scope defined by the claims of the present invention.
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