Method for treating copper smelting refining slag by using pyrolusite

Abstract

The invention discloses a method for treating copper smelting refining slag by using pyrolusite, which comprises the following steps: step 1, respectively crushing and grinding the pyrolusite and the copper smelting refining slag, and mixing Cu2O in the copper smelting refining slag and MnO2 in the pyrolusite according to a molar ratio of 1: 1; 2, a sulfuric acid solution is added into the mixture of the pyrolusite and the copper smelting refining slag for leaching, and the liquid-solid ratio is 4: 1-11: 1 ml / g; and 3, Mn, Fe, As, Zn and the like in the leachate in the step 2 are removed through an extraction agent Lix984 extraction separation technology, and a pure mixed solution of the copper sulfate solution and the manganese sulfate solution is obtained after extraction and purification. According to the method, the pyrolusite is used as the oxidizing agent to treat the copper smelting refining slag, so that the aim of extracting valuable metals in the copper smelting refining slag while treating the pyrolusite can be achieved. The pyrolusite is adopted to directly leach the copper smelting refining slag to recover valuable metals such as copper and manganese in the copper smelting refining slag, so that on one hand, resource recycling is realized, and on the other hand, the purpose of reducing the cost is also achieved.

Description

Technical Field

[0001] The present invention relates to a method for recycling metal resources, and in particular to a method for treating copper smelting and refining slag with pyrolusite. Background Art

[0002] Manganese in pyrolusite mainly exists in the form of MnO2, and tetravalent manganese therein cannot be directly leached by dilute acid and needs to be reduced to divalent manganese before it can be leached. The reduction leaching methods of pyrolusite are divided into pre-reduction leaching method and direct reduction leaching method. The pre-reduction leaching method has large resource consumption, complex process and will cause great pollution to the environment, which is obviously not suitable for the current environmental protection requirements in China. The direct reduction leaching method reduces energy consumption, has a simple process and little environmental pollution, so it has better development prospects. In order to make the reduction leaching of pyrolusite more economical and environmentally friendly, it is crucial to select a suitable reducing agent for the reduction leaching of pyrolusite.

[0003] China occupies a dominant position in the world's copper consumption, but its own copper ore resources are not rich. In the refining process of anode furnace with purple miscellaneous copper as raw material, in addition to producing anode copper, a large amount of refining slag with a copper content of about 20-40% is also produced. In addition to Cu, the refining slag also contains elements such as Fe, As, Pb, Zn, etc. Among them, the main copper phase in the refining slag is mainly Cu2O.

[0004] Copper smelters generally return this kind of refining slag to the copper smelting furnace or sell it at a low price. If the refining slag is returned to the copper smelting furnace, the actual processing capacity of the copper smelting furnace will be reduced, and harmful impurities will be closed-loop circulated and accumulated in the system, reducing the quality of copper products. If the refining slag is sold at a low price, the economic benefits of the enterprise will inevitably be reduced. Due to the nature and value of the refining slag, it determines that the refining slag becomes an important comprehensive recovery point in the copper smelting process and also a concentrated disposal point for toxic and harmful elements in the copper smelting process.

[0005] In view of the current treatment status of pyrolusite and copper smelting refining slag, how to organically combine the two and effectively extract manganese and copper therein to realize the recycling of metal resources is a very meaningful research topic. Summary of the Invention

[0006] Object of the Invention: Aiming at the above problems, the object of the present invention is to provide a method for treating copper smelting and refining slag with pyrolusite, which can greatly reduce the treatment cost of pyrolusite and copper smelting refining slag and realize the effective extraction of manganese and copper therein.

[0007] Technical Solution: A method for treating copper smelting and refining slag with pyrolusite includes the following steps:

[0008] Step 1: Crush and grind pyrolusite and copper smelting and refining slag respectively, and mix them according to the molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite of 1:1;

[0009] Step 2: Add sulfuric acid solution to leach the mixture of pyrolusite and copper smelting and refining slag, and the liquid-solid ratio is 4:1 - 11:1 ml / g;

[0010] Step 3: Use the extractant Lix984 extraction and separation process for the leachate in Step 2 to remove impurities in the leachate, and obtain a mixed solution of pure copper sulfate solution and manganese sulfate solution after extraction and purification. The impurities in the leachate include Mn, Fe, As, Zn, etc.

[0011] Further, the copper smelting and refining slag is obtained by copper pyrometallurgical refining, and contains 20 - 40% Cu, 15 - 25% Fe, 15 - 25% Si, 15 - 25% O, 1 - 3.5% As, 1 - 3% Zn, 1 - 3% P, 0.5 - 2% Pb, 0.1 - 2% Ca, 0.1 - 0.5% Co, 0.1 - 1% Mn.

[0012] Preferably, the copper phase in the copper smelting and refining slag includes Cu2O, accounting for 80% - 95% of the copper phase.

[0013] Further, the pyrolusite contains 25 - 40% Mn, 15 - 25% Fe, 15 - 30% Al, 3.5 - 8% Si, 1 - 3.5% K, 2 - 4% Ca, 1 - 4% Ti, 0.7 - 2% Zn, 0.2 - 1% Mg.

[0014] Further, in Step 2, the leaching temperature during sulfuric acid solution leaching is 65 - 85°C, the time is 1 - 5 h, and the H2SO4 concentration is 1 - 3 mol / L.

[0015] Further, the particle sizes of the ground pyrolusite and copper smelting and refining slag are both less than 200 mesh.

[0016] Preferably, in Step 3, the existing forms of manganese ions and copper ions in the leachate are Mn 2+ , Cu 2 + .

[0017] Beneficial effects: Compared with the prior art, the advantages of the present invention are:

[0018] 1. By using pyrolusite as an oxidant to treat copper smelting and refining slag, the present invention can achieve the purpose of treating pyrolusite while extracting valuable metals from copper smelting and refining slag.

[0019] 2. The present invention directly leaches copper smelting and refining slag with pyrolusite to recover valuable metals such as copper and manganese. On the one hand, it realizes the recycling of resources, and on the other hand, it also achieves the purpose of reducing costs.

[0020] 3. The process of the present invention has a wide application range, less pollution and low energy consumption, and is an environmentally friendly and efficient method for recovering valuable metals.

[0021] 4. The leachate obtained by the present invention is a mixed solution of copper sulfate and manganese sulfate containing impurities such as Zn and Fe. After impurity removal, extraction and purification, a mixed solution of pure copper sulfate solution and manganese sulfate solution is obtained. The copper sulfate solution can be returned to the copper electrolysis system or directly used to produce copper powder and other copper extraction methods, which will provide a new method for the comprehensive utilization of refining slag. The manganese sulfate solution can be used to prepare the anode material of lithium batteries, which will provide new ideas for the treatment of pyrolusite.

[0022] 5. The present invention has significant economic and environmental advantages, will provide important guidance for the industrial production of the comprehensive utilization of manganese-containing materials, can be widely applied to manganese ores in the manganese smelting industry, and can also be applied to the recovery and utilization of manganese in waste catalysts and oxidants in the synthetic industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is the process flow chart of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be further clarified below in conjunction with the drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention.

[0025] A method for treating copper smelting and refining slag with pyrolusite, as Figure 1 shown, includes the following steps:

[0026] Step 1: Crush and grind pyrolusite and copper smelting and refining slag respectively and then mix them. The particle sizes of pyrolusite and copper smelting and refining slag after grinding are both less than 200 mesh;

[0027] Step 2: Add sulfuric acid solution to leach the mixture of pyrolusite and copper smelting and refining slag, and the liquid-solid ratio is 4:1 - 11:1 ml / g;

[0028] Step 3: Purify the leachate in Step 2 through impurity removal, extraction and purification to obtain a mixed solution of pure copper sulfate solution and manganese sulfate solution.

[0029] Among them, the copper sulfate solution can be returned to the copper electrolysis system or directly used to produce copper powder and other copper extraction methods, and the manganese sulfate solution can be used to prepare the anode material of lithium batteries.

[0030] The main chemical reactions occurring during the leaching process are as follows:

[0031] Cu2O + MnO2 + 3H2SO4 = 2CuSO4 + MnSO4 + 3H2O;

[0032] Cu2O + H2SO4 = CuSO4 + Cu + H2O;

[0033] Cu + MnO2 + H2SO4 = CuSO4 + MnSO4 + H2O;

[0034] Al2O3 + 3H2SO4 = Al2(SO4)3 + 3H2O;

[0035] ZnFe2O4 + 4H2SO4 = ZnSO4 + Fe2(SO4)3 + 4H2O;

[0036] Fe3O4 + 4H2SO4 = FeSO4 + Fe2(SO4)3 + 4H2O.

[0037] The following is illustrated with specific embodiments.

[0038] Example 1:

[0039] Leaching is carried out by adding pyrolusite powder containing 40.02%, 20.58%, 20.89%, 7.15%, 3.14%, 4.00%, 2.80%, 1.21% and 0.21% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively into copper smelting and refining slag containing 20.12%, 25.38%, 20.86%, 24.58%, 3.45%, 2.10%, 2.15%, 1.10%, 0.16% and 0.10% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively. In the copper smelting and refining slag, Cu2O accounts for 79.89% of the copper phase. Under the leaching conditions of temperature 65°C, liquid-solid ratio (ml / g) 6:1, time 1 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 1 mol / L, the leaching rate of Cu is 72.28% and the leaching rate of Mn is 73.90%.

[0040] Example 2:

[0041] Pyrolusite powder containing 37.84%, 19.52%, 24.68%, 6.97%, 2.17%, 3.84%, 2.66%, 1.49% and 0.83% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively was added to copper smelting and refining slag containing 22.93%, 22.65%, 21.84%, 24.46%, 3.46%, 1.89%, 1.75%, 0.49% and 0.53% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively for leaching. In the copper smelting and refining slag, Cu2O accounted for 82.63% of the copper phase. Under the leaching conditions of temperature 80 °C, liquid-solid ratio (ml / g) 5:1, time 4 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 3 mol / L, the leaching rate of Cu was 77.32% and the leaching rate of Mn was 78.54%.

[0042] Example 3:

[0043] Pyrolusite powder containing 35.65%, 13.88%, 29.46%, 8.63%, 2.98%, 3.79%, 3.62%, 1.99% and 0.72% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively was added to copper smelting and refining slag containing 25.48%, 18.69%, 24.65%, 21.74%, 2.82%, 3.59%, 1.98%, 0.35% and 0.70% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively for leaching. In the copper smelting and refining slag, Cu2O accounted for 85.85% of the copper phase. Under the leaching conditions of temperature 85 °C, liquid-solid ratio (ml / g) 9:1, time 5 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 2.5 mol / L, the leaching rate of Cu was 79.50% and the leaching rate of Mn was 79.45%.

[0044] Example 4:

[0045] The pyrolusite powder containing 34.79%, 20.89%, 29.97%, 3.68%, 2.33%, 3.15%, 3.57%, 0.91% and 0.78% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively was added to the copper smelting and refining slag containing 26.17%, 24.98%, 22.75%, 19.39%, 3.47%, 1.45%, 0.53%, 0.93%, 0.16% and 0.12% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively for leaching. In the copper smelting and refining slag, Cu2O accounted for 86.39% of the copper phase. Under the leaching conditions of temperature 80°C, liquid-solid ratio (ml / g) 10:1, time 3.5 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 3 mol / L, the leaching rate of Cu was 85.81% and the leaching rate of Mn was 85.14%.

[0046] Example 5:

[0047] The pyrolusite powder containing 30.12%, 22.38%, 24.89%, 7.95%, 3.48%, 2.98%, 3.99%, 2.21% and 2.00% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively was added to the copper smelting and refining slag containing 30.10%, 24.34%, 16.89%, 20.12%, 1.88%, 1.45%, 2.30%, 1.83%, 0.50% and 0.59% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively for leaching. In the copper smelting and refining slag, Cu2O accounted for 90.49% of the copper phase. Under the leaching conditions of temperature 80°C, liquid-solid ratio (ml / g) 10:1, time 3.5 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 3 mol / L, the leaching rate of Cu was 90.12% and the leaching rate of Mn was 89.21%.

[0048] Example 6:

[0049] Pyrolusite powder containing 25.32%, 24.58%, 28.88%, 7.95%, 3.50%, 4.00%, 2.98%, 1.88% and 0.91% of Mn, Fe, Al, Si, K, Ca, Ti, Zn and Mg respectively was added to copper smelting and refining slag containing 39.50%, 20.30%, 17.6%, 15.12%, 1.45%, 2.51%, 1.98%, 0.56% and 0.98% of Cu, Fe, Si, O, As, Zn, P, Pb, Ca, Co and Mn respectively for leaching. In the copper smelting and refining slag, Cu2O accounts for 94.73% of the copper phase. Under the leaching conditions of temperature 75°C, liquid-solid ratio (ml / g) 8:1, time 4 h, molar ratio of Cu2O in the copper smelting and refining slag to MnO2 in the pyrolusite 1:1, and sulfuric acid concentration 2 mol / L, the leaching rate of Cu is 94.18% and the leaching rate of Mn is 92.5%.

Claims

1. A method for treating copper smelting and refining slag with pyrolusite, characterized in that It includes the following steps: Step 1: Crush and grind pyrolusite and copper smelting refining slag respectively, and mix them according to the molar ratio of Cu2O in the copper smelting refining slag to MnO2 in the pyrolusite of 1:1; Step 2: Add sulfuric acid solution to leach the mixture of pyrolusite and copper smelting refining slag, and the liquid-solid ratio is 4:1 - 11:1 ml / g; Step 3: Use the extractant Lix984 extraction separation process for the leachate in Step 2 to remove impurities in the leachate, and obtain a mixed solution of pure copper sulfate solution and manganese sulfate solution after extraction and purification.

2. The method for treating copper smelting and refining slag by using pyrolusite according to claim 1, wherein: The copper smelting refining slag is obtained by copper pyrometallurgical refining and contains 20 - 40% Cu, 15 - 25% Fe, 15 - 25% Si, 15 - 25% O, 1 - 3.5% As, 1 - 3% Zn, 1 - 3% P, 0.5 - 2% Pb, 0.1 - 2% Ca, 0.1 - 0.5% Co, 0.1 - 1% Mn.

3. A method for treating copper smelting and refining slag with pyrolusite according to claim 1 or 2, characterized in that: The phase of copper in the copper smelting refining slag includes Cu2O, accounting for 80% - 95% of the copper phase.

4. A method for treating copper smelting and refining slag by using pyrolusite according to claim 1, characterized in that: The pyrolusite contains 25 - 40% Mn, 15 - 25% Fe, 15 - 30% Al, 3.5 - 8% Si, 1 - 3.5% K, 2 - 4% Ca, 1 - 4% Ti, 0.7 - 2% Zn, 0.2 - 1% Mg.

5. A method for treating copper smelting and refining slag with pyrolusite according to claim 1, characterized in that: In Step 2, the leaching temperature during sulfuric acid solution leaching is 65 - 85°C, the time is 1 - 5 h, and the H2SO4 concentration is 1 - 3 mol / L.

6. A method for treating copper smelting and refining slag by using pyrolusite according to claim 1, characterized in that: The particle sizes of the ground pyrolusite and copper smelting refining slag are both less than 200 mesh.

7. A method for treating copper smelting and refining slag by using pyrolusite according to claim 1, characterized in that: In step 3, the existing forms of manganese ions and copper ions in the leaching solution are Mn 2+ and Cu 2+ .

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