A study on the oxidative-addition reaction of benzyl compounds in sulphuric acid and its relation to corrosion inhibition

An investigation of organic compounds that inhibit iron corrosion in sulphuric acid by way of oxidative addition to iron was carried out by electrochemical measurements and time-dependent analysis of chemical species in solution to which iron powder was added. Benzyl thiocyanate exhibited high corrosion inhibition effects by formation of a protective film on the iron surface via the oxidative-addition reaction. Characteristics of oxidative-addition corrosion inhibitors, represented as R-X, were discussed in terms of the facility of cutting the R-X bond and the stability of X^- by using force constants of the CH₃X bonds and pK_a values of HX as the respective parameters.