Corrosion protection of tin by some carboxylic acids in sodium chloride solution

Abstract

Tin is a moderately corrosion resistant material that is widely used in tinplate for food beverages. However, despite its excellent corrosion resistance, the presence of oxidizing agents enhances tin dissolution. Dissolution of metallic tin, especially from the inside of a can body into the food content has a major influence on the food quality and may cause toxicological effects. To overcome the problem, different chemical compounds are added. The most utilized inhibitors in the food industry are nitrites and nitrates well-known as hazardous to health. The present study aimed to investigate the influence of carboxylic acids on the corrosion resistance of tin since they are present in fruit juices and different foodstuffs. The corrosion protection efficiency of the carboxylate coatings was investigated in a sodium chloride solution using electrochemical and spectroscopic techniques. The structural characteristics of the surface coatings were investigated using the FTIR spectroscopy and optical microscope.