DEVELOPMENT OF CORROSION INHIBITORS FOR STAINLESS STEEL IN HYDROCHLORIC ACID

The effects of 5 kinds of different corrosion inhibitors on the stainless steel immersed in 8% hydrochloric acid medium were tested respectively using weight-loss and scanning electron microscopy methods.The experiments indicated that imidazoline and hexadecyl trimethyl ammonium bromide had good anti-corrosion property.When hexadecyl trimethyl ammonium bromide was used independently with concentration of 700 mg/L,the inhibitive efficiency was 90.0%.The corrosion inhibition efficiency of hexadecyl trimethyl ammonium bromide mixed with triethanolamine,imidazoline,and thiourea,respectively,were 91.8%,90.8%,89.7%.The inhibitive efficiency of the mixtures of imidazoline,thiourea,methenamine and imidazoline,thiourea,triethanolamine were all over 90%.The price of inhibitors are lower also,so they are the ideal composite corrosion inhibitors.The corrosion on the surface of metal in hydrochloric acid with inhibitors was slight,the surface of metal was smooth,and no pitting corrosion occurred.