Anticorrosive protection of steel with Drotaverine in 0,5 M H2SO4 solution

Abstract

It is known that organic compounds are the most effective corrosion inhibitors. The main disadvantages of their use are the high cost, as well as the fact that by their nature they can be toxic. As a result there was a need to find new safe, cheap and effective corrosion inhibitors. This list can include drugs that can act as potential inhibitors due to the presence of nitrogen, sulfur, etc. atoms in their structure. The paper examines the possibility of using the expired drug Drotaverine as a corrosion inhibitor of carbon steel in 0.5 M H₂SO₄. The concentration of the drug was 20…80 mg/l – Gravimetry, scanning electron microscopy (SEM), potentiodynamic polarization, electrochemical diffusion and impedance spectroscopy were used to determine the most effective concentration of Drotaverine – 80 mg/l, which corresponded to a protective effect of 95%. All studies were conducted at room temperature. A decrease in the capacity of the double electric layer in the presence of an inhibitor indicates the adsorption of the drug components on the metal surface. The results of polarization measurements showed that Drotaverine is a mixed-type inhibitor. Analysis of the state of the metal surface by means of a scanning electron microscope after exposure to an inhibited solution allows us to judge the high protective effectiveness of Drotaverine in the highest concentration under study.