In nature, except for mineral particles such as coal, graphite, talc and molybdenite, which have hydrophobic surfaces and are naturally floatable, most mineral deposits are hydrophilic, and the same is true for gold deposits. Adding an agent can change the hydrophilicity of mineral particles and produce hydrophobicity to make them floatable. This agent is generally called a collector. Collecting agents are generally polar collectors and non-polar collectors. Polar collectors are composed of polar groups that can interact with the surface of mineral particles and non-polar groups that have a hydrophobic effect. When this type of collector is adsorbed on the surface of mineral particles, its molecules or ions are arranged in an orientation, with the polar groups facing the surface of the mineral particles and the non-polar groups facing outward to form a hydrophobic film, thereby making the mineral site floatable. . For gold associated with sulfide mineral deposits such as copper, lead, zinc, iron, etc., organic thio compounds are often used as collectors during flotation. For example, alkyl (ethyl, propylene, butyl, pentyl, etc.) sodium dithiocarbonate ( Potassium), also known as, commonly known as xanthate. For example, NaS2C·OCH2·CH3, when flotating gold-bearing polymetallic ores, ethyl xanthate and butyl xanthate are mostly used. Alkyl dithiophosphates or their salts, such as (RO)2PSSH, where R is an alkyl group, are commonly known as black medicine.
foaming agent
For gold associated with sulfide mineral deposits such as copper, lead, zinc, iron, etc., organic thio compounds are often used as collectors during flotation. For example, alkyl (ethyl, propylene, butyl, pentyl, etc.) sodium dithiocarbonate ( Potassium), also known as, commonly known as xanthate. For example, NaS2C·OCH2·CH3, when flotating gold-bearing polymetallic ores, ethyl xanthate and butyl xanthate are mostly used. Alkyl dithiophosphates or their salts, such as (RO)2PSSH, where R is an alkyl group, are commonly known as black medicine. Alkyl disulfide salts and ester derivatives are also commonly used collectors for sulfide mineral deposits. It is also a commonly used collector for the flotation of gold-bearing polymetallic sulfide ores, and is often used together with xanthate. The molecules of non-ionic polar collectors do not dissociate, such as sulfur-containing esters, and the non-polar collectors are hydrocarbon oils (neutral oils), such as kerosene, diesel, etc.
Surface-active molecules with hydrophilic and hydrophobic groups are directionally adsorbed at the water-air interface, reducing the surface tension of the aqueous solution and making the air filled in the water easily disperse into bubbles and stable bubbles. The foaming agent and collector are combined to adsorb on the surface of the mineral particles, causing the mineral particles to float. Commonly used foaming agents include: pine oil, commonly known as No. 2 oil, phenolic acids mixed with fatty alcohols, isomeric hexanol or pungent alcohol, ether alcohols and various esters.
Adjusters can be divided into five categories: (1) pH adjusters. It is used to adjust the pH of the slurry to control the surface properties of the mineral deposit, the chemical composition of the slurry and the effect conditions of various other chemicals, thereby improving the flotation effect. In the chemical process, it is also necessary to adjust the pH value of the slurry. Commonly used ones include lime, sodium carbonate, and sulfuric acid. When selecting gold, the most commonly used conditioners are lime and sulfuric acid. (2) Activator. It can enhance the functional ability of mineral deposits and collectors to activate and float difficult-to-float mineral deposits. The gold-containing lead-copper oxide ore is activated and then flotated using xanthate and other collectors. (3) Inhibitors: Improve the hydrophilicity of mineral deposits and prevent the mineral deposits from interacting with collectors, thereby inhibiting their floatability.
For example, in the preferential flotation process, lime is used to suppress pyrite, zinc sulfate and sphalerite are used to suppress sphalerite, water glass is used to suppress silicate gangue minerals, etc., and organic substances such as starch and gum (tannin) are used as suppressors to achieve many goals. The purpose of metal separation and flotation. (4) Flocculant. Aggregate fine particles of mineral deposits into large particles to accelerate their sedimentation speed in water; use selective flocculation to perform flocculation-desliming and flocculation-flotation. Commonly used flocculants include polyamide and starch. (5) Dispersant. It prevents the aggregation of fine mineral particles and keeps them in a monomer state. Its effect is exactly the opposite of that of flocculants. Commonly used ones include water glass, phosphate, etc.
Post time: Aug-21-2024
