"

Cookies ussage consent

Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our site without changing the browser settings you grant us permission to store that information on your device.

I agree, do not show this message again.

Sodium tripolyphosphate (STPP) as a novel corrosion inhibitor for mild steel in 1 M HCl

I. FAHIM1, A. KHEIREDDINE1, S. BELAAOUAD1

Affiliation

  1. Laboratoire de Chimie-Physique des Matériaux, Faculté des Science Ben M’Sik. Bd Cdt Driss El Harti B.P 7955. Casablanca. Morocco

Abstract

The corrosion inhibition of mild steel in 1 M HCl solution by sodium triphosphate (STPP), Na5P3O10, has been studied using potentiodynamic polarisation as an electrochemical technique, weight loss and UV–vis spectrophotometric measurement. The results of weight loss and Tafel polarization measurements showed that this compound has fairly good inhibiting properties for steel corrosion in acidic bath, with 87% inhibition efficiency at optimum concentration 10-3 M. The inhibition is of a mixed anodic–cathodic nature. The adsorption behaviour of the investigated compound is found to obey Langmuir adsorption isotherm. Negative value was calculated for the energy of adsorption indicating the spontaneity of the adsorption process. The formation of complex between metal cations and sodium triphosphate is also proposed as additional inhibition mechanism of mild steel corrosion..

Keywords

Sodium tripolyphosphate, Corrosion, Complexation, Inhibitor, Steel, Acid.

Submitted at: April 17, 2013
Accepted at: June 12, 2013

Citation

I. FAHIM, A. KHEIREDDINE, S. BELAAOUAD, Sodium tripolyphosphate (STPP) as a novel corrosion inhibitor for mild steel in 1 M HCl, Journal of Optoelectronics and Advanced Materials Vol. 15, Iss. 5-6, pp. 451-456 (2013)