Studies On Corrosion Inhibition On Brass In Hydrochloric Acid Solution

Content: The corrosion velocity and corrosion inhibition efficiency of many kinds of compound for brass in 10% hydrochloric acid was studied using the weight-loss method, then some kinds of compounds with certain corrosion inhibition effect have been got in 10% hydrochloric acid solution.In these compounds hexamethylenetetramine, diethylenetriamine and eathylene diamine tetraacetic acid selected as research object. Their corrosion inhibition action for brass was studied with different temperatures in 10% hydrochloric acid by adsorption theory and electrochemical polarization-curve method, the mechanism of corrosion inhibition action was analyzed. The results indicated that the single molecule layer of these compounds adsorbed on the surface of brass and almost followed Langmiur isothermal equation. The adsorption procedure of hexamethylenetetramine, diethylenetriamine and eathylene diamine tetraacetic acid was a heat-absorbing reaction, the adsorption ability and corrosion inhibition efficiency increased with increasing in temperature. They are all positive type inhibitor. The corrosion current was decreased by them in different degree.A composite and excellent corrosion inhibitor was composed by orthogonal method. The corrosion inhibition action of this composite corrosion inhibitor has been evaluated by using weight-loss method, electrochemical polarization-curve method and scanning electron microscopy techniques. The corrosion rate of brass in hydrochloric acid has been determined with different concentration of hydrochloric acid, different temperature and different time. The composite corrosion inhibitor is positive type inhibitor. The SEM photos indicated that no signal of was found under different corrosion condition. It shows that the composite corrosion inhibitor is an excellent corrosion inhibitor for brass in hydrochloric acid solution.