Substituted Biguanides as Inhibitors: Surface Adsorption on Iron

Inhibitors are used in the acid pickling of steel to reduce the attack of acid on the metal. It has been found that organic polar compounds such as amines and qi∼inolines act as good inhibitors.lV2 It is believed that inhibitor action depends on surface adsorption of the inhibitor on the metal. Perhaps it is a case of chemisorption.s.4.s Biguanide have activated nitrogen atoms due 'to which they are easily adsorbed on the surface of metalic iron.