Corrosion Inhibition by Flower Extracts - At a Glance

Flower extract are ecofriendly corrosion inhibitors. They have been used to control corrosion of mild steel, copper and aluminium in various media. The mechanistic aspects have been investigated by electrochemical studies such as polarisaiton study and AC impedance spectra. The protective film has been analysed by FTIR, SEM, EDX and AFM. The adsorption isotherms isotherms being obeyed are Langmuir, Temkin and Freundlich adsorption isotherms. The flowers extract primarily function as mixed type of inhibitors. The active principles mainly present in colored flowers are anthocyanins, and carotenoids. They contain polar groups such as hydroxyl, methoxy and ether. These ingredients coordinate with the metal ions on the metal surface through oxygen atom, benzene ring and conjugated double bonds. The protective film formed on the metal surface controls the corrosion process. Keywords: Corrosion Inhibition; Flower Extract; AFM; SEM; FTIR; Isotherms; Green Inhibitors