The effect of natural inhibitor concentration of Fumaria officinalis and temperature on corrosion protection mechanism in API X80 pipeline steel in 1 M H2SO4 solution. (December 2020)

• Record Type: Journal Article
• Authors: Golchinvafa, Amir; Mousavi Anijdan, S.H.; Sabzi, Masoud; Sadeghi, Majid
• Is Part Of: International journal of pressure vessels and piping. Volume 188(2020)
• Publication Date: 2020-12
• Subjects: API X80 pipeline steel -- Fumaria officinalis -- Inhibitor concentration -- Medium temperature -- Corrosion protection; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2020.104241
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: In this investigation, the effect of Fumaria officinalis concentration, as a natural inhibitor, and the medium temperature on the corrosion prevention mechanism of an API X80 pipeline steel alloy in the solution of 1 M H2 SO4 is studied. For this purpose, corrosion behavior of the pipeline steel in the solution of 1 M H2 SO4 at the presence of 0, 2, 4 and 6 g/L Fumaria officinalis inhibitor at medium temperatures of 20 °C, 40 °C and 60 °C was assessed. To assess the corrosion protection mechanism of the API X80 pipeline steel under these conditions, Open Circuit Potential (OCP), Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy (EIS) tests were conducted. As well, Scanning Electron Microscopy (SEM) equipped with Energy Dispersive Spectroscopy (EDS) detector was used to analyze the corrosion products formed on the surface of the pipeline specimens. Results of OCP and potentiodynamic polarization tests showed that Fumaria officinalis reduces the speed of both anodic and cathodic reactions. Also, Δ G ads 0 calculation showed that Fumaria officinalis led to the reduction of anodic and cathodic reactions through its physical-chemical adsorption on the surface and blocking of corrosion active locations. The results of EIS tests indicated that with increasing the Fumaria officinalis inhibitor, the corrosion resistance of the API X80 pipeline steel increased. As well, corrosion products analysis showed that Iron sulfide compounds were formed on the surface of the specimens. In terms of the medium temperature, results showed that increasing the temperature of the solution from 20 °C to 60 °C has led to an increased corrosion rate and efficiency reduction of Fumaria officinalis. Moreover, it was defined that the adsorption process of Fumaria officinalis on the surface of the API X80 pipeline steel at the temperature of 40°Cin the 1 M H2 SO4 solution followed adsorption isotherm of Langmuir. Highlights: The OCP shifts towards more negative values in the OCP curves with increasing the medium temperature. With Fumaria officinalis, OCP variations was an ascending trend; i.e. passive film forms. Fumaria officinalis in 1 M H2 SO4 acts as an anodic or cathodic agent of pipeline steel. Δ G ads 0 showed that physical absorption was taking place on the surface with Fumaria officinalis. Increasing medium temperature lowers the solution resistance & decreases corrosion resistance.