Electroplating of Steel in the Presence of 5,6-Dihydropyrimidine-2-(1H)-thione, 2-Methylthiopyrimidine-4-(1H)-one, 2-Thiopyrimidine-4-(1H)-ones,and 2,4-Pyrimidine(1H,3H)-dione Derivatives as Organic Additives

The electrode processes on steel in acidified CuSO₄ were finding to depend on the organic additives as well as their concentrations. They also depend on the type of the anode and temperature. The activation energy proves that the reaction is diffusion controlled. The percentage of inhibition for all solutions ranged from 6.9% to 44.7% and depended on the type of the cathode and the concentration of the additive. The order of inhibition efficiency of steel cathode is: compound 4 > compound 5 > compound 3 > compound 2 > compound 6 > compound 1. The overall mass transfer correlation proves that the electroplating reaction is natural convection, which is in accordance with our previous studies.