Copper oxide is a black oxide of copper. In nature, copper is a typical sulphurophile element, mainly in the form of copper sulfide, but copper oxide minerals will be formed under strong oxidizing conditions.
Copper oxide is insoluble in water and/alcohol, soluble in acid, ammonium chloride and potassium cyanide solution, slow to dissolve in ammonia solution, can react with strong alkali, copper oxide is widely used in dry manufacture of ceramics, enamel, glaze, desulfurizer etc., can also be used to make oxygen, catalysts and green glass.
In the beneficiation process, most copper oxides need to be sulfided by chemicals, and then beneficiate. Compared with dry copper sulfide, the selection is more complicated and more chemicals are used. The beneficiation process of copper oxide (including oxygen-sulfur mixed copper ore) can be divided into two categories: flotation method and chemical beneficiation method. Below we mainly describe these two types of beneficiation processes.
Copper oxide flotation method
Flotation is one of the commonly used beneficiation processes for copper oxide ore. According to the different properties of copper oxide ore, there are sulfide flotation, fatty acid flotation, amine flotation, and emulsion.
Flotation method and sting mixture-neutral oil flotation method, etc.
1. Vulcanization flotation method
Sulfation flotation method is divided into conventional sulfidation flotation and hydrothermal sulfidation flotation.
Conventional sulfidation flotation: This method is to first sulfide copper oxide minerals (using sodium sulfide or other vulcanizing agents), and then use good xanthate collectors to conduct flotation operations. The lower the value, the faster the vulcanization operation, and the more easily vulcanized with vulcanizing agents such as sodium sulfide.
The copper oxide minerals treated by the sulfide flotation method are mainly copper carbonates, such as malachite, azurite and other minerals, or cuprite, but the dry silica malachite needs special treatment first, otherwise the sulfurization effect Not good, not even vulcanized.
Note: When oxidizing copper minerals, it is recommended to add vulcanizing agents step by step, so that ammonium sulfate and aluminum sulfate can help the vulcanization of oxidized minerals.
Hydrothermal sulfidation flotation: This method extends the conventional sulfidation flotation method, which is to carry out the sulfidation operation under hot pressing conditions, so that sulfur chemically reacts with copper oxide under hot pressing conditions.
In order to obtain stable and easy-to-select man-made copper sulfide minerals, the same minerals are recovered by flotation of copper sulfide in warm water.
This method strengthens the pre-treatment of ore - the process of pre-vulcanization, but this process has high requirements on temperature, large fuel consumption and long vulcanization time.
2. Fatty acid flotation method
Fatty acid flotation, also known as direct flotation, mainly uses fatty acids and their soaps as collectors. During flotation, gangue inhibitor water glass, phosphate and slurry conditioner sodium carbonate are usually added.
Fatty acid and soap collectors can flotate malachite and azurite well, and use fatty acids with different hydrocarbon chains to flotate malachite. As long as the hydrocarbon chain is long enough, its collecting ability is very strong.
The fatty acid flotation method mostly uses dry gangue which is not a carbonate copper oxide mineral. If the gangue contains a large amount of iron, manganese and other minerals, its indicators will deteriorate, and the mesh sludge will also cause the fatty acid to fail.
3. Amine flotation method
This method mainly uses amines as collectors for flotation, which can not only be used for the separation of copper oxide, but also a common beneficiation method for copper oxide, lead and zinc minerals. Chlorothalmine, etc.
Amine type collectors are selective in choosing copper oxide, because amines also have a collection effect on many gangues. Before sorting, pre-desliming is required, but for argillaceous copper oxide, pre-desliming will lead to copper Therefore, the premise of choosing amine flotation method is to find an effective inhibitor of gangue first.
At present, gangue inhibitors include seaweed powder, xylinate (or cellulose xylosulfonate) and polyacrylic acid.
4. Emulsion flotation method
The flotation method is mainly to vulcanize copper oxide minerals first, then add copper complexing agents to form a stable lipophilic mineral surface, and then use neutral oil emulsion to cover the mineral surface.
surface, resulting in a highly hydrophobic floatable state, so that minerals can be firmly attached to the bubbles to complete the selection.
Emulsion flotation includes three aspects:
First, it is necessary to use selective organic copper complexing agent compounds, such as benzotriazole toluoyl triazole, mercaptobenzothiazole, diphenylguanidine, etc.;
One is to re-add non-polar oil emulsion to improve the adhesion between minerals and air bubbles. Non-polar oil emulsifiers include gasoline, kerosene and some oils, etc.
Third, selective inhibitors such as acrylic polymers and sodium silicate are required.
5. Chelating agent-neutral oil flotation method
This method refers to the use of a certain chelating agent and a neutral oil to form a collector to complete the flotation. It is mostly used for difficult-to-select copper oxides (such as silica malachite), which not only has high selectivity and collection effect, but also can It can ensure a high sorting index while reducing the consumption of chemicals, and the chelating agent also has a selective inhibitory effect.
However, the cost of the chelating agent is relatively high. At present, the chelating agents used include the basic dye malachite green substituted by octyl, potassium octyl hydroxamate, benzotriazole and neutral oil emulsifier, N-substituted iminodiethyl , acid salts, polyamines and condensates of organic halides, etc.
Chemical beneficiation method
Chemical beneficiation methods are commonly used in dry refractory separation of copper oxide and mixed copper minerals with oxidation and sulfide. The use of chemical beneficiation method-combined process of copper oxide ore process can obtain good indicators, and it has many advantages such as simple process flow, low investment, low energy consumption, light pollution and low production cost.
The above are some common beneficiation methods for copper oxide minerals. For the selection of copper oxide minerals, it is necessary to determine the mineral composition and degree of difficulty of copper oxide minerals. It is recommended to find professional miners to conduct beneficiation tests, and customize the report according to the actual situation. In order to effectively select useful minerals from other places, remember not to apply them indiscriminately.
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