Electrooxidation xanthate

Chronologically there were almost no reports on this topic prior to the early 1980s, and the first of these concerned studies on xanthate electrooxidation to assist froth flotation in mineral-ore recovery. The mechanisms of flotation are not completely imderstood, and for xanthates the involvement of dixanthogen and other species has been proposed. In an early paper, combined use of ultrasound and electrooxidation was found to increase the amount of dixanthogen and give a uniform emulsion with 80% of droplets below 5 pm diameter, improving the recoveries of galena, sphalerite, and chalcopyrite. ... 

Later reports identified butyl monothiocarbonate disulfide (Bu02C)2S2 and bis(butylxanthogen) among the sonoelectrochemical products from butyl xanthate electrooxidation (Eq. l). The apparatus for the sonoelectrochemical activation of flotation reagents is described. i The benefits of sonoelectro-chemistry were confirmed in a recent paper on the sonoelectrooxidation of sodium butylxanthate. 2 jhe same effects were obtained imder 50-Hz (audible sound) and 20-kHz (ultrasound) irradiation. Insonation power details are not easy to compare from the report, but this result has considerable implications for... 

Nickel(III) xanthates, Ni(S2COR)3, with R = Me, Et, Pr, z-Pr, Bu, z-Bu, sec-Bu, can be quantitatively generated in acetonitrile solution by electrooxidation of anionic [Ni(S2COR)3] or by oxidative addition of ethyldixanthogen, [EtOC(S)S]2 to Ni(S2COEt)2. Solutions of Ni(S2COR)3 readily disproportionate into Ni(S2COEt)2 and [EtOC(S)S]2.240... 

---