Revista internacional de investigación y desarrollo en farmacia y ciencias biológicas

Abstracto

STUDY OF NATURALLY OCCURRING BIOCIDE AS CORROSION INHIBITOR FOR STAINLESS STEEL IN ACIDIC MEDIUM

M. Kalpana Devi Felicia Rajammal Selvarani

The present study was carried out with 1,3,5 Tri Methyl Xanthine(TMX) is also called caffeine a naturally occurring substance found in the extracts of leafs of Green tea and Beans of coffee Arabica as corrosion inhibitor for the corrosion of stainless steel in acid medium. Caffeine is found to have biocidal efficiency and prevents microbial corrosion. The corrosion behaviour of stainless steel in 1.0 M HCl solution by weight loss (at 30o C and 40o C), and electrochemical techniques were carried out. Experimental results reveal that inhibition efficiency increases with increasing inhibitor concentration up to a maximum of 83% and it decreases with increase of temperature. The best fit adsorption isotherm for the experimental data was Langmuir adsorption isotherm. Tafel polarization analysis reveals that the studied compound is a mixed type inhibitor.