Anticorrosion behavior of bioemulsions on metal-environment interface

Abstract

The influence of Ricinus communis oil on electrochemical corrosion of steel in oil-in-water emulsions under controlled hydrodynamic condition was investigated. Emulsions from renewable biobased sources have gained prominent role in food and pharmaceutical industries as green excipients. The emulsion system under study was prepared from ricinus communis oil, hexadecyl polyglucoside and brine solution in which ricinus communis oil constitute the non-polar phase and surfactant constitute polar phase. The efficiency and effectiveness of these emulsion system highly influenced by their constituents and composition. Thus the stability of the as-prepared emulsion is analyzed through the optimization of various emulsion formulation factors such as viscosity, and creaming rate. The stability of emulsion was observed to increase with viscosity since it makes the particles to distribute evenly. The application of the emulsion on metallic surface under controlled hydrodynamic conditions was studied using potentiodynamic polarization Tafal plots. The newly formulated emulsion showed corrosion inhibition on the tested alloy steel and their corrosion rate was reduced to 0.5598 mm/year.The antimicrobial activity of this versatile emulsion was also assessed using in-vitro assay. This emulsion formulation can be used economically in industrial application as it may reduce the preventive maintenance, replacement of corroded equipment and contamination of product.

Keywords

• Ricinoleic acid
• Corrosion potential
• Oil-in-water emulsion
• Corrosion inhibition