Flotation Performance and Mechanism of Thiocarbamates

In particular, the effect of the size of alkyl linked with N atom (N— R) on seleclivily of thiocarbamate is very obvious. 

For the flotation of Cu-Zn-Fe sulfide ore, the selectivity indexes of various thio-carbamates can be given as follows  

The functional mechanism of thiocarbamates had been discussed briefly in Chap. 3 (Volume 1) and Chap. 6 (Volume 1). It was reported that [20], the adsorption of thiocarbamate on pyrite is weaker than that of xanthate, and fliio-carbamate is prone to desorb from pyrite surface in water. But thiocarbamate adsorbs on towanite firmly. Based on potentiometry of A.B. Glembotski, thiocarbamate adsorbs on towanite and molybdenite via chemical adsorption. And the chemical adsorption between thiocarbamate and towanite is obvious at pH 8. But chemical adsorption cannot take place between thiocarbamate and pyrite. Compared with thiocarbamate, there exists chemical adsorption occurring between xanthate and the above minerals. And the chemical adsorption of xanthate weakens with increasing the pulp pH. 

According to the structural features, the bonding group of thiocarbamate can be expressed by the following  

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