1-PHENYL-5-MERCAPTO-1,2-3,4-TETRAZOLE (PMT) - A NEW CORROSION-INHIBITOR FOR CU-ZN ALLOY

Some tetrazole-type organic compounds have been tested as corrosion in hibitors for copper-zinc (70/30) alloy in 0.1M H2SO4 solution by gravi metric and electrochemical polarisation methods. Results obtained show ed that 1-Phenyl-5-mercapto-1,2,3,4-tetrazole (PMT) was the best inhib itor. Its inhibition efficiency (E%) reached 93 % at 10(-6)M and 99% a t 10(-3)M. The effect of temperature in the range 20-90 degrees C on t he corrosion of Cu-Zn alloy in 0.1M H2SO4 without and with addition of 10(-4) M PMT has been studied. The associated activation energy has b een determined.