Method for treating beneficiation wastewater through electrocatalytic oxidation

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a method for treating beneficiation wastewater by electrocatalytic oxidation, which comprises the following steps: constructing a three-dimensional electrolysis system by a particle electrode, an anode and a cathode, and performing electrocatalytic oxidation treatment on the beneficiation wastewater; the particle electrode comprises nitrogen-sulfur co-doped carbon aerogel and perovskite oxide, and the perovskite oxide is loaded on the nitrogen-sulfur co-doped carbon aerogel to realize combination of functions of the nitrogen-sulfur co-doped carbon aerogel and the perovskite oxide, so that a better treatment effect on beneficiation wastewater is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and specifically to a method for electrocatalytic oxidation treatment of ore dressing wastewater. Background Art

[0002] The lead-zinc ore dressing process generally adopts the process flow of "lead preferential flotation - regrinding of lead concentrate middlings - activation of tailings to select zinc - regrinding of zinc rough concentrate". The ore dressing tailings water contains ethyl thionocarbamate, butyl xanthate, pine oil, sulfide, etc. As a result, the COD value and metal ion content of the ore dressing wastewater are relatively high. If it is directly discharged without treatment, it will cause environmental pollution of the surrounding water bodies, endanger the ecological environment and human health. If it is directly recycled, the residual ore dressing agents and activated metal ions in the wastewater will affect the separation indexes of lead and zinc.

[0003] The three-dimensional electrolysis method is an advanced oxidation method that fills conductive particles as particle electrodes in a traditional two-dimensional electrolytic cell to make pollutants react on the surface of the particle electrodes. This method has the advantages of high degradation efficiency, simple operation, green environmental protection, etc. However, at present, the application of this technology in ore dressing wastewater has not been seen, and the existing particle electrodes generally have the problem of low catalytic performance. Summary of the Invention

[0004] Purpose of the Invention: Aiming at the above technical problems, the present invention proposes a method for electrocatalytic oxidation treatment of ore dressing wastewater.

[0005] The technical solution adopted is as follows: A method for electrocatalytic oxidation treatment of ore dressing wastewater: The particle electrode, anode and cathode together construct a three-dimensional electrolysis system to carry out electrocatalytic oxidation treatment on the ore dressing wastewater; The composition of the particle electrode includes nitrogen and sulfur co-doped carbon aerogel and perovskite oxide.

[0006] Further, the perovskite oxide is Ag x La 1-x MO3; 0 < x ≤ 0.1; M is any one or a combination of two or more of Mn, Fe, Co, and Ni.

[0007] Further, the preparation method of the nitrogen and sulfur co-doped carbon aerogel is as follows: After mixing formaldehyde, resorcinol, cetyltrimethylammonium bromide and deionized water, add them to peanut oil, carry out suspension polymerization reaction at 80 - 90 °C for 5 - 10 d, then filter to obtain an organic wet gel. Age the organic wet gel in deionized water for 5 - 10 d, wash it, and then perform low-temperature freeze-drying to obtain an organic dry gel. Mix the organic dry gel, ammonium thiocyanate and deionized water, carry out hydrothermal reaction at 160 - 180 °C for 5 - 10 h, take it out, wash it, and perform low-temperature freeze-drying again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, calcine the nitrogen and sulfur co-doped organic dry gel at 800 - 1000 °C for 1 - 3 h under nitrogen protection.

[0008] Further, the mass ratio of the organic dry gel to ammonium thiocyanate is 1:50 - 100.

[0009] Further, x = 0.02.

[0010] Further, the preparation method of the particle electrode is as follows: Dissolve Ag salt, La salt, M salt and citric acid in deionized water, add the nitrogen and sulfur co-doped carbon aerogel and polyethylene glycol and mix them evenly. Adjust the pH of the solution to 7 - 8 with ammonia water. Stir the obtained mixed solution at 60 - 80 °C for 1 - 10 h, then dry and dehydrate to obtain a precursor. Grind the precursor and calcine it at 600 - 800 °C for 5 - 10 h.

[0011] Further, the anode is a titanium-based ruthenium oxide coated anode.

[0012] Furthermore, the anode is any one of RuO2 / Ti, RuO2 - TiO2 / Ti, RuO2 - SnO2 - TiO2 / Ti and RuO2 - Ta2O5 / Ti.

[0013] Further, the cathode is a stainless steel electrode.

[0014] Further, the dosage of the particle electrode in the ore dressing wastewater is 10 - 100 g / L.

[0015] Further, the current density during electrocatalytic oxidation treatment is 40 - 60 mA / cm 2 .

[0016] The beneficial effects of the present invention: The present invention provides a method for electrocatalytic oxidation treatment of ore dressing wastewater. A combination of nitrogen and sulfur co-doped carbon aerogel and perovskite oxide is used as a particle electrode. Under the action of an external electric field, the particle electrode is induced to be charged and undergoes repolarization, so that the two ends of the particle are respectively induced as the anode and the cathode, forming an independent microelectrode for the whole particle, and multiple micro electrolytic cells are formed between the particle and the surrounding solution. A large number of free radicals are generated in these micro electrolytic cells to catalytically degrade organic pollutants and dissociate heavy metal ions. The carbon aerogel has a large surface area and good adsorption performance. After nitrogen and sulfur co-doping, nitrogen-containing groups such as graphitic nitrogen, pyridine nitrogen and pyrrole nitrogen are introduced, increasing the active sites and forming an electron-rich region with a high spin density to regulate the local charge, thereby improving the reaction activity of sp 2 hybridized carbon and realizing the improvement of the electrochemical activity of the carbon aerogel. However, the self-catalytic oxidation effect of the carbon material is weak, and the B-site metal ions of the perovskite oxide have catalytic activity. Loading it on the carbon aerogel can combine the functions of the two. Doping of Ag ions at the A-site of the perovskite oxide can not only generate oxygen vacancies but also change and adjust the valence state of the cations at the B-site, improving the electrochemical activity of the perovskite oxide while increasing the conductivity, thereby achieving a better treatment effect on the ore dressing wastewater. Specific embodiments

[0017] For those not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For reagents or instruments not specified in the manufacturer, they are all conventional products that can be obtained through commercial purchase. Technologies not mentioned in the present invention refer to the prior art. Unless otherwise specified, the following examples and comparative examples are parallel tests and adopt the same treatment steps and parameters.

[0018] Example 1: A method for electrocatalytic oxidation treatment of ore dressing wastewater: Mix the overflow water of lead-zinc tailings and the intercepted seepage water of the tailings pond in a ratio of 1:1, and take the supernatant as the ore dressing wastewater sample after standing for 10 h. The water quality of the ore dressing wastewater sample is shown in Table 1 below: Table 1:

[0019] Add the above beneficiation wastewater to a cylindrical three-dimensional electrode reactor. The reactor is made of plexiglass, with a diameter of 40 mm, a height of 100 mm, and a wall thickness of 3 mm. The anode plate uses a RuO2-TiO2 / Ti electrode, and the cathode uses a stainless steel plate. The distance between the anode and the cathode is 4 cm, and they are vertically placed in the reactor. There is an aeration device at the bottom of the reactor. Through aeration, the particle electrodes filled between the cathode and the anode can flow freely. In order to reduce the adsorption of the particle electrodes on the beneficiation wastewater during the reaction process, before the electrocatalytic oxidation treatment, the particle electrodes are immersed in the beneficiation wastewater for 10 h until adsorption saturation. The dosage of the particle electrodes is 10 g / L. When the electrocatalytic oxidation treatment starts, the aeration volume is adjusted to 50 ml / min, and the current intensity is 50 mA / cm 2 , and the electrocatalytic oxidation treatment time is 60 min. After 60 min, samples are taken for testing and analysis of the water quality changes. The results are shown in Table 2 below: Table 2:

[0020] Among them, the particle electrode consists of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 MnO3. The preparation method of the particle electrode is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide, and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization reaction at 80 °C for 7 d, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 d, then wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature to obtain an organic dry gel. After mixing the organic dry gel and ammonium thiocyanate in a mass ratio of 1:60, add them to deionized water at a solid-liquid mass ratio of 1:10. After sealed hydrothermal reaction at 170 °C for 7 h, restore to room temperature, collect the precipitate, wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain nitrogen and sulfur co-doped carbon aerogel. Dissolve 3.4 mg of silver nitrate, 319 mg of lanthanum nitrate, 179 mg of manganese nitrate, and 384 mg of citric acid in 50 ml of deionized water, add 5 g of nitrogen and sulfur co-doped carbon aerogel and 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. After stirring the obtained mixed solution at 70 °C for 5 h, then raise the temperature to 100 °C for drying and dehydration to obtain a precursor. Grind the precursor into powder and calcine it at 700 °C for 5 h.

[0021] Example 2: Basically the same as Example 1, the difference is that the particle electrode consists of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98Composed of FeO3, the preparation method of the particle electrode is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization reaction at 80 °C for 7 d, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 d, then wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature to obtain an organic dry gel. After mixing the organic dry gel and ammonium thiocyanate with a mass ratio of 1:60, add them to deionized water at a solid-liquid mass ratio of 1:10. After sealed hydrothermal reaction at 170 °C for 7 h, restore to room temperature, collect the precipitate, wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain a nitrogen and sulfur co-doped carbon aerogel. Dissolve 3.4 mg of silver nitrate, 319 mg of lanthanum nitrate, 242 mg of iron nitrate and 384 mg of citric acid in 50 ml of deionized water, add 5 g of nitrogen and sulfur co-doped carbon aerogel and 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. After stirring the obtained mixed solution at 70 °C for 5 h, then raise the temperature to 100 °C for drying and dehydration to obtain a precursor. Grind the precursor into powder and calcine it at 700 °C for 5 h.

[0022] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 3 below: Table 3:

[0023] Example 3: Basically the same as Example 1, the difference is that the particle electrode is composed of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 CoO3, and the preparation method of the particle electrode is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization reaction at 80 °C for 7 days, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 days, then wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature to obtain an organic dry gel. After mixing the organic dry gel and ammonium thiocyanate at a mass ratio of 1:60, add them to deionized water at a solid-liquid mass ratio of 1:10. After sealed hydrothermal reaction at 170 °C for 7 h, restore to room temperature, collect the precipitate, wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain a nitrogen and sulfur co-doped carbon aerogel. Dissolve 3.4 mg of silver nitrate, 319 mg of lanthanum nitrate, 183 mg of cobalt nitrate and 384 mg of citric acid in 50 ml of deionized water, add 5 g of nitrogen and sulfur co-doped carbon aerogel and 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. After stirring the obtained mixed solution at 70 °C for 5 h, then raise the temperature to 100 °C for drying and dehydration to obtain a precursor. Grind the precursor into powder and then calcine it at 700 °C for 5 h.

[0024] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 4 below: Table 4:

[0025] Example 4: It is basically the same as Example 1, except that the particle electrode is composed of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 NiO3. The preparation method of the particle electrode is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide, and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization at 80 °C for 7 days, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 days, then wash it thoroughly with absolute ethanol and deionized water, and finally freeze-dry it at low temperature to obtain an organic dry gel. Mix the organic dry gel and ammonium thiocyanate at a mass ratio of 1:60, and add them to deionized water at a solid-liquid mass ratio of 1:10. Seal and carry out hydrothermal reaction at 170 °C for 7 h, then restore to room temperature. Collect the precipitate and wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain a nitrogen and sulfur co-doped carbon aerogel. Dissolve 3.4 mg of silver nitrate, 319 mg of lanthanum nitrate, 183 mg of nickel nitrate, and 384 mg of citric acid in 50 ml of deionized water, add 5 g of nitrogen and sulfur co-doped carbon aerogel and 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. Stir the obtained mixed solution at 70 °C for 5 h, then raise the temperature to 100 °C to dry and dehydrate to obtain a precursor. Grind the precursor into powder and calcine it at 700 °C for 5 h.

[0026] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 5 below: Table 5:

[0027] Comparative Example 1: It is basically the same as Example 1, except that carbon aerogel is used as the particle electrode. The preparation method of carbon aerogel is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide, and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization at 80 °C for 7 days, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 days, then wash it thoroughly with absolute ethanol and deionized water, and finally freeze-dry it at low temperature to obtain an organic dry gel. Place the organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection.

[0028] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 6 below: Table 6:

[0029] It can be seen from the comparison with Example 1 that using carbon aerogel as the particle electrode, the treatment effect on ore dressing wastewater is far inferior to that of the nitrogen and sulfur co-doped carbon aerogel and Ag 0.02La 0.98 The particle electrode composed of La and 0.98 MnO3 has good treatment effect on the beneficiation wastewater.

[0030] Comparative Example 2: It is basically the same as Example 1, except that nitrogen and sulfur co-doped carbon aerogel is used as the particle electrode. The preparation method of the nitrogen and sulfur co-doped carbon aerogel is as follows: After mixing 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide and 100 ml of deionized water, add them to 500 ml of peanut oil. After suspension polymerization reaction at 80 °C for 7 d, filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 d, then wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature to obtain an organic dry gel. After mixing the organic dry gel and ammonium thiocyanate with a mass ratio of 1:60, add them to deionized water with a solid-liquid mass ratio of 1:10. Seal and carry out hydrothermal reaction at 170 °C for 7 h, then restore to room temperature. Collect the precipitate and wash it thoroughly with absolute ethanol and deionized water, and then freeze-dry it at low temperature again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain the nitrogen and sulfur co-doped carbon aerogel.

[0031] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 7 below: Table 7:

[0032] By comparing with Example 1 and Comparative Example 1, it can be seen that using nitrogen and sulfur co-doped carbon aerogel as the particle electrode, although the treatment effect on the beneficiation wastewater is not as good as that of the particle electrode composed of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 MnO3, it is better than using carbon aerogel as the particle electrode for the treatment effect of the beneficiation wastewater.

[0033] Comparative Example 3: It is basically the same as Example 1, except that Ag 0.02 La 0.98 MnO3 is used as the particle electrode; Ag 0.02 La 0.98 The preparation method of MnO3 is as follows: Dissolve 3.4 mg of silver nitrate, 319 mg of lanthanum nitrate, 179 mg of manganese nitrate and 384 mg of citric acid in 50 ml of deionized water, add 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. Stir the obtained mixed solution at 70 °C for 5 h and then raise the temperature to 100 °C for drying and dehydration to obtain a precursor. Grind the precursor into powder and calcine it at 700 °C for 5 h.

[0034] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 8 below: Table 8:

[0035] It can be seen from the comparison with Example 1 that using Ag alone 0.02 La 0.98 MnO3 as the particle electrode has a worse treatment effect on the ore dressing wastewater than the particle electrode composed of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 MnO3 combined.

[0036] Comparative Example 4: It is basically the same as Example 1, except that the particle electrode is composed of nitrogen and sulfur co-doped carbon aerogel and LaMnO3. The preparation method of the particle electrode is as follows: Mix 6 g of formaldehyde, 11 g of resorcinol, 1 g of cetyltrimethylammonium bromide and 100 ml of deionized water, add them to 500 ml of peanut oil, carry out suspension polymerization reaction at 80 °C for 7 d, and then filter to obtain an organic wet gel. Age the organic wet gel in 500 ml of deionized water for 7 d, wash it thoroughly with absolute ethanol and deionized water, and then perform low-temperature freeze-drying to obtain an organic dry gel. Mix the organic dry gel and ammonium thiocyanate with a mass ratio of 1:60, add them to deionized water at a solid-liquid mass ratio of 1:10, carry out a sealed hydrothermal reaction at 170 °C for 7 h, restore to room temperature, collect the precipitate, wash it thoroughly with absolute ethanol and deionized water, and perform low-temperature freeze-drying again to obtain a nitrogen and sulfur co-doped organic dry gel. Finally, place the nitrogen and sulfur co-doped organic dry gel in a muffle furnace and calcine it at 900 °C for 2 h under nitrogen protection to obtain a nitrogen and sulfur co-doped carbon aerogel. Dissolve 325 mg of lanthanum nitrate, 179 mg of manganese nitrate and 384 mg of citric acid in 50 ml of deionized water, add 5 g of nitrogen and sulfur co-doped carbon aerogel and 35 mg of polyethylene glycol 200 and mix well. Adjust the pH of the solution to 8 with ammonia water. Stir the obtained mixed solution at 70 °C for 5 h and then raise the temperature to 100 °C for drying and dehydration to obtain a precursor. Grind the precursor into powder and calcine it at 700 °C for 5 h.

[0037] The electrocatalytic oxidation treatment time is 60 min. After 60 min, sample and test to analyze the water quality change. The results are shown in Table 9 below: Table 9:

[0038] By comparing with Example 1, it can be seen that the particle electrode composed of nitrogen and sulfur co-doped carbon aerogel and Ag 0.02 La 0.98 MnO3 has a better treatment effect on the mineral processing wastewater than the particle electrode composed of nitrogen and sulfur co-doped carbon aerogel and LaMnO3, indicating that Ag doping plays a positive role in improving the treatment effect.

[0039] The above embodiments 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for treating mineral processing wastewater by electrocatalytic oxidation, characterized in that: The particle electrode, anode and cathode together form a three-dimensional electrolysis system to perform electrocatalytic oxidation treatment on mineral processing wastewater; The particle electrode comprises nitrogen-sulfur co-doped carbon aerogel and perovskite oxide.

2. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The perovskite oxide is Ag x La 1-x MO3; 0＜x≤0.1； M is any one of Mn, Fe, Co and Ni, or a combination of two or more thereof.

3. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The preparation method of the nitrogen-sulfur co-doped carbon aerogel is as follows: After formaldehyde, resorcinol, hexadecyltrimethylammonium bromide and deionized water are mixed, the mixture is added to peanut oil, and the mixture is subjected to suspension polymerization reaction at 80-90°C for 5-10 days, and then filtered to obtain an organic wet gel. The organic wet gel is aged in deionized water for 5-10 days, washed, and then freeze-dried at low temperature to obtain an organic xerogel. After the organic xerogel, ammonium thiocyanate and deionized water are mixed, the mixture is subjected to hydrothermal reaction at 160-180°C for 5-10 hours, and then taken out, washed, and freeze-dried at low temperature again to obtain a nitrogen-sulfur co-doped organic xerogel. Finally, the nitrogen-sulfur co-doped organic xerogel is calcined at 800-1000°C for 1-3 hours under nitrogen protection.

4. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 3, characterized in that: The mass ratio of the organic dry gel to ammonium thiocyanate is 1:50-100.

5. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 2, characterized in that: x=0.02。 6. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 2, characterized in that: The preparation method of the particle electrode is as follows: Ag salt, La salt, M salt and citric acid are dissolved in deionized water, nitrogen-sulfur co-doped carbon aerogel and polyethylene glycol are added and mixed, the pH value of the solution is adjusted to 7-8 with ammonia water, the obtained mixed solution is stirred at 60-80°C for 1-10h and then dried and dehydrated to obtain a precursor, the precursor is ground and calcined at 600-800°C for 5-10h.

7. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The anode is a titanium-based ruthenium oxide coating anode.

8. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The cathode is a stainless steel electrode.

9. The method for treating ore dressing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The dosage of particle electrode in mineral processing wastewater is 10-100g / L.

10. The method for treating mineral processing wastewater by electrocatalytic oxidation according to claim 1, characterized in that: The current density during electrocatalytic oxidation treatment is 40-60 mA / cm 2 .

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