ECOTOXICITY AND CORROSION INHIBITION EFFECT OF QUINOLONIUM AND IMIDAZOLIUM SALTS

Abstract

The corrosion inhibition of steel in the hydrochloric acid solution by N-butylquinolinium bromide and 1-octyl-3-methylimidazolium chloride was investigated using electrochemical and weight loss methods. Both compounds under investigation act as mixed type inhibitors with predominantly anodic action. The Gibbs energy of adsorption was calculated by means of the Langmuir isotherm. The inhibition efficiency of 1-octyl-3-methylimidazolium chloride was higher. Daphnia magna was used as acute toxicity test organism. 1-octyl-3-methylimidazolium chloride was more toxic than N-butylquinolinium bromide. The LC 50 value (48 hours) for 1-octyl-3-methylimidazolium chloride for acute test on Daphnia magna was 0.020 mg  l -1 and it was 1.271 mg  l -1 for N-butylquinolinium bromide. 1-octyl-3-methylimidazolium chloride can be classified as extremely toxic substance (LC 50 is 0.01-0.1 mg  l -1 ) and N-butylquinolinium bromide can be classified as moderate toxic substance (LC 50 is 1-10 mg