Dynamics of electrodeposition of tetraethylthioram disulphide (TETD) on pyrite surface

Abstract

The electrode process of pyrite in diethyldithiocarbamate (DDTC) solution pH 11.4 was investigated by using cyclic voltammetry, potentiostatic and chronopotentiometry. Tetraethylthioram disulphide (TETD) was electrodeposited on pyrite electrode surface as the electrode potential is higher than 0.2 V. The relationship of the current density caused by diffusion and reaction time can be ascertained as i=1/(9.08×10−5+4.77×10−3 t 0.5), and the diffusion coefficient of DDTC on pyrite surface is about 3.72×10−6 cm2/s. At pH 11.4, the thickness of TETD adsorbed on pyrite surface is about 1.63 molecule layer. The electrochemical dynamics equation of the reduction of TETD on pyrite surface is given as η=0.116−0.064log[1−(t/τ)0.5]. The kinetic parameters were determined as follows: the exchange current density (i 0) is 3.08 µA/cm2; the transmission coefficient(α) is 0.462.