Xanthate was first synthesized and studied by Zeise in 1815. Because of its yellow color, it was called yellow medicine. In the general formula, Me is sodium or potassium, and some are made into ammonium salts. R is alkyl groups, alkylaryl groups, cycloalkyl groups, alkoxy groups, etc. of different sizes. Commonly used ones include ethyl xanthate, butyl xanthate, isopropyl xanthate, isobutyl xanthate, pentyl xanthate, hexyl xanthate, etc. The scientific name is hydrocarbyl xanthate or hydrocarbyl dithiocarbonate, which is regarded as a derivative in which the two oxygens in carbonic acid are replaced by sulfur. Xanthate is widely used. It is used as a vulcanization accelerator in the rubber industry. Potassium ethylxanthate is used as a precipitant and colorimetric reagent for copper, nickel and other metal ions in analytical chemistry. In the metallurgical industry, xanthate is used as a precipitate from a solution. Cobalt and nickel reagents, cellulose sodium xanthate are used to make artificial fibers. It is generally believed that the use of xanthate as a collector in flotation began in 1924, when Keller registered a patent in the United States. In 1929, Foster published a method for manufacturing xanthate and its organic thiocarbonate. Xanthate is currently the most widely used sulfide ore collector. It is estimated that the amount of various types of xanthate used in flotation around the world ranges from tens of thousands to nearly 100,000 tons per year. There are more than ten commonly used xanthate varieties in terms of basic components. There are many kinds of products, and there are even more brand names. The molecular structure of xanthate is closely related to the flotation performance. Generally speaking, the longer the carbon chain in the xanthate molecule, the stronger its collection ability, that is, it increases with the increase in the molecular weight of the alcohol group; with branched chains The homologous isomer has a stronger collection effect than the straight chain.
Copper ore and iron ore use more butylxanthate.
The interaction between butyl xanthate, chalcopyrite and pyrite
When the pH is 6.86, the reaction products of chalcopyrite, pyrite and butyl xanthate are all is a collector dimer. Under the action of the high pH adjuster CaO and the oxidizing high pH adjuster CaOCl2, the surface oxidation rate of pyrite is higher than the oxidation rate of butyl xanthate to the corresponding bixanthate, so the flotation of pyrite is affected. Inhibition is an important aspect of the action of CaO and CaOCl2 on pyrite. On the other hand, it generates hydrophilic calcium-containing compounds on the surface of pyrite.
Under appropriate potential conditions, xanthate is oxidized on the surface of chalcopyrite and pyrite, generating the corresponding bixanthate product, resulting in the hydrophobization of the collector on the surface of chalcopyrite and pyrite. and flotation: