What are the flotation reagents for lead-zinc ore?

Lead-zinc ore in my country is mainly sulfide ore, mainly galena and sphalerite. For this type of lead-zinc ore, flotation is mainly used to achieve mineral separation and separation. However, with the gradual reduction of sulfide ore, oxidized lead-zinc ore has gradually entered the developers' field of vision. For separation, it is more difficult. In the flotation process, the selection of lead-zinc ore flotation method is the top priority, but flotation reagents cannot be ignored. This article will focus on the flotation reagents of lead-zinc ore.

At present, the commonly used mineral processing reagents for lead-zinc ore flotation are mainly collectors and inhibitors.

011. Lead-zinc ore collectors

The main function of the collector is to change the surface properties of the mineral through physical or chemical reactions with the mineral surface, making it easy to be captured by flotation bubbles and taken out of the slurry. At present, the types of lead-zinc ore collectors commonly used in ore dressing plants include yellow medicine, black medicine, dithiocarbamate (ester), thiocarbamate and mixed reagents.

Xanthate:Xanthate collectors used for lead-zinc ore are mainly xanthate and xanthate esters. This type of agent is relatively cheap and easy to produce, but its disadvantage is that its stability and selectivity are weak. Ethyl xanthate and butyl xanthate are more commonly used.

Black medicine:Compared with xanthate, the collection ability is weaker, but black medicine has foaming properties, so less or no foaming agent can be used. Commonly used black medicines include No. 25 black medicine, butylamine and aniline black medicines, etc. In mineral processing, the dosage of black medicine is generally higher than that of xanthate, and the flotation speed is slow, but the selectivity of black medicine collectors for iron sulfide minerals is better than that of xanthate.

Dithiocarbamates (esters): This type of collector has a strong collection ability for orphenite and chalcopyrite, but weaker for pyrite, so its selectivity is better. Under pH conditions, flotation can improve the separation effect between zinc and lead-zinc, and can reduce the use of sodium cyanide. The dosage of this type of agent is only half or even one-tenth of that of xanthate, and the flotation speed is fast. Commonly used ones are ethylthiocyanate and butylthiocyanate.

Thiocarbamate: This type of collector has good selectivity, strong foaming ability and small dosage. Its collection ability is weaker than butyl xanthate, but it has a strong collection effect on chalcopyrite, chalcocite and activated sphalerite, and does not float pyrite. It is a highly selective collector. When treating complex and difficult-to-process lead-zinc ores, it can be used in combination with other collectors. In some beneficiation plants, in order to improve its dispersibility, it is often added to the grinding process. The commonly used thiocarbamate is Z-200, which is relatively stable under alkaline and acidic conditions and has higher selectivity and stability than xanthate and black medicine.

Mixed reagent: It is a mixture of two or more reagents, and the flotation effect is better. For example, ethyl xanthate and ethylthiocyanate as a mixed reagent have a better flotation effect on lead ore than either of them as collectors alone, and the reagent dosage is small and the collection sensitivity is higher.

022. Lead-zinc ore inhibitors

The main function of the inhibitor is to physically or chemically react with the mineral surface of the gangue mineral during the flotation process to keep it hydrophilic and prevent it from combining with the flotation bubbles and floating up. In the flotation operation of lead-zinc ore, the commonly used inhibitors are lime, cyanide, zinc sulfate, sulfurous acid, sulfite, etc.

Lime:In lead-zinc ore flotation, it can not only be used as an inhibitor, but also as a pH adjuster, flocculant and heavy metal precipitant. However, the foaming performance of pine oil will be affected by the increase in pH value caused by the addition of lime. In addition, due to the coagulation of lime, the flotation effect is affected to a certain extent.

Cyanide:Among the inhibitors for lead-zinc separation, sodium cyanide has a better inhibitor effect, but it is less used because of its toxicity.

Zinc sulfate: is a inhibitor of sphalerite. When used alone, zinc sulfate has a poor inhibitory effect and is usually used in combination with cyanide, sulfite or thiosulfate, sodium sulfide, sodium carbonate, etc.

Sulfurous acid, sulfite: Sulfite and sulfite mainly have sulfite ions adsorbed on the surface of the inhibited mineral to inhibit pyrite and sphalerite. The inhibited sphalerite can be activated by adding CuSO.

The above are the types of reagents commonly used in lead-zinc ore flotation plants. In actual ore dressing plants, how to choose reagents and how much to use depends on the properties of lead-zinc ore, the processing capacity of the ore dressing plant, etc. Therefore, it is recommended to conduct ore dressing tests, and design suitable lead-zinc ore dressing methods through experimental analysis, and customize suitable reagent dosage and reagent system.