Copper, lead, zinc, sulfur separation method

(1) The floatability of copper minerals

1. Chalcopyrite CuFeS2, containing Cu 34.57%. Porphyry copper deposit.

Collector : low-grade xanthate, black medicine.

Mechanism: chemical adsorption, with copper ions to form copper xanthate; physical adsorption, adsorption of Fe3+ ion surface in the form of double xanthate.

Inhibitors: CN-, NaCN, kCN, k4[Fe(CN)6], k3[Fe(CN)6], all used in alkaline media. H2O2 and NaClO reduce their floatability by peroxidation and are used in acidic media.

Activator: CuSO4.

2. The floatability of the copper ore and copper (belonging to the secondary copper deposit)

Copper ore Cu2S: Containing 79.83% of Cu, the best floatability is natural.

Tonglan CuS: Containing Cu 64.4%, natural floatability is very good.

Collector: low-grade xanthate, black medicine, PH value 1~13.

The mechanism is the same as above.

Inhibitors: Na2OS3, Na2S2O3, k4[Fe(CN)6], k3[Fe(CN)6], Na2S, all used in an alkaline medium.

Cyanide suppression is poor.

Characteristics: These two minerals are all brittle, the grinding is easy to mud, the solubility is relatively large, the recovery rate is low, the [Cu2+] ion content in the pulp is high, which makes the inhibition difficult and easily activates other minerals. The flotation selectivity is poor.

3. The copper-bearing Cu5FeS4 has a Cu content of 63.3%, and the floatability is between the above two minerals (1) and (2).

The collector is the same as above, and the PH value is 5~10.

Inhibitor: CN-, lime is used in alkaline media.

General law: (1) Where iron minerals are not contained, the floatability is similar, and CN- and lime inhibit them weakly.

(2) For iron-containing minerals, CN- and lime can inhibit their floatability in alkaline media.

(3) The higher the copper content, the better the floatability.

(2) The floatability of lead minerals

A representative mineral is galena. PbS contains 86.6% Pb, crystallized in cubic crystal, and has good natural floatability.

Collector:

1, PH value <9.5 low grade xanthate. The PH value is best between 7 and 8, and the pH is adjusted with Na2CO3.

2. The PH value is between 9.5 and 10.5 with high-grade xanthate.

3, PH value > 10.5 rear lead ore is subject to certain inhibition.

The collection mechanism is chemical adsorption, and the product is lead xanthate.

Inhibitor: Knox reagent (K2CrO4 + KCrO2), Na2S, CaO. Activation after inhibition: Knox reagent inhibition is activated with NaCl in HCl or acidic medium, which is activated with CuSO4 in an acidic medium.

CN-no inhibition. (except when iron is included).

(3) Sphalerite ZnS with a Zn content of 67.10%.

Natural floatability is weaker than both 1 and 2.

Collector: After activation with Cu2+, it is harvested with xanthate. If not activated, the xanthate is ineffective.

Inhibitors: CN-, NaCN, kCN, ZnSO4, Na2SO3 (sodium sulfite), Na2S2O3 (sodium thiosulfate).

Characteristics: Fe and Cd are often mixed with the same type. Causes a decrease in floatability, making suppression easier. Among them, Cd needs to be recycled, and currently Cd is derived from the recovery from sphalerite.

(4) The floatability of iron sulfide minerals

1. The floatability of pyrite

FeS2, containing S 53.4%.

It has a certain natural hydrophobicity, but it is not sufficient, and its surface is properly oxidized to facilitate the collection of xanthate. Excessive oxidation can reduce buoyancy.

Collector: In the weakly acidic medium, use yellow medicine to collect.

Mechanism: Electrochemical adsorption mechanism. The xanthate is first oxidized into a double xanthate. The lone pair of electrons in the xanthate are combined with the empty orbital of Fe2+ ions, and the xanthate is adsorbed on the mineral surface by lone pair electrons.

Inhibitor: lime, cyanide.

Activator: lime inhibits activation with sulfuric acid and sodium carbonate to form calcium sulfate and calcium hydrogen sulfate to analyze the adsorption of Ca on the mineral surface;

Cyanide inhibition is activated by copper sulfate.

2. Magnetic pyrite

Fe1-xS, x: 0.1~0.2, its floatability is weaker than pyrite, it is collected by high-grade xanthate, and the inhibitor is the same as pyrite.

2. Separation of copper, lead, zinc and sulfur (short for various sulfide ores)

(1) Separation of copper and sulfur

Method: Depends on the nature of the ore. There are two main methods.

1. Priority flotation: suitable for dense massive ore, Cu and S can be fully monomer dissociated under relatively coarse grinding particle size conditions.

Order: Suppresses the first copper float.

2, mixed flotation: suitable for the combination of Cu and S in the ore, the aggregate size of Cu and S is relatively coarse, and when the particle size of the monomer is fine, the qualified tailings are first extracted by mixed flotation, then Cu and S mixed concentrate is then removed from the drug and then separated.

Conditions: The collector of Cu is xanthate or black medicine, lime is used as a pH adjuster and an inhibitor of iron minerals, and if necessary, cyanide is added to assist the inhibition. Activator: only lime inhibition, activated with sulfuric acid, sodium carbonate, calcium sulfate and calcium hydrogen sulfate to analyze the adsorption of Ca on the mineral surface; combined with cyanide inhibition, activated with sulfuric acid and copper sulfate.

(2) Separation of lead and zinc

Priority flotation method, inhibition of sphalerite, and capture of galena.

Collector: low-grade xanthate, advanced xanthate, black medicine. Usually separated in an alkaline medium.

Inhibitors: CN-, NaCN, kCN, ZnSO4, Na2OS3, Na2S2O3.

Activator: copper sulfate. Then use advanced xanthate to collect.

(3) Separation of copper and zinc

Priority flotation, inhibition of sphalerite, and capture of copper minerals. The separation of lead and zinc with a separation difficulty greater than 2 should strengthen the inhibition of zinc.

Collector: low-grade xanthate, advanced xanthate, black medicine. Usually separated in an alkaline medium.

Inhibitors: CN-, NaCN, kCN, ZnSO4, Na2OS3, Na2S2O3.

Activator: copper sulfate. Then use advanced xanthate to collect.

(4) Separation of copper and lead

Generally, the mixed concentrate of copper and lead is separated, and the drug is removed first, followed by flotation.

Drug removal method: mechanical method, re-grinding drug, stirring and washing, Na2S drug removal, activated carbon adsorption and drug removal, heating, roasting, etc.

1. Suppressing lead float copper

Applicable to secondary copper ore, Cu2+ ion dissolution is more difficult to suppress.

Inhibition of lead: Knox reagent (K2CrO4 + KCrO2) and Na2S are used together;

Or oxygen sulfur method: 1) SO2 (or sulfurous acid) + starch; 2) sulfurous acid, sodium sulfide; 3) sodium thiosulfate + ferric chloride or ferrous sulfate; 4) sodium carbonate ferrous sulfate.

2, inhibit copper lead

Suitable for primary copper mines. Collecting agent: xanthate, black medicine, PH value 9~9.5, adjusted with CaO.

Inhibitor: Cyanide and its alternative inhibitors. Or warming and removing drugs to inhibit lead 40~70 °C (pH value ≤ 7).

(5) Separation of zinc and sulfur

The process of suppressing sulfur and flotation of zinc is adopted.

Collector: Xanthate, zinc must be activated by copper sulfate.

Inhibitor and pH adjuster: lime.

Technical Instruction of the Equipment