CORROSION INHIBITION BY SHOREA ROBUSTA (SAAL) BARK EXTRACT FOR MILD STEEL CORROSION IN 1 M H2SO4 SOLUTION
Date
2023-08-17
Authors
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Publisher
Amrit Campus
Abstract
A novel corrosion inhibitor for mild steel (MS) corrosion has been extracted in
methanol solvent from Shorea robusta bark. Qualitative chemical tests, VU, and FTIR
measurements were carried out to confirm phytochemicals in the extract. The
inhibition efficiency of extract has been studied by using weight loss and
potentiodynamic polarization methods. The weight loss measurement has been
adopted for the study of inhibitor concentration effect as well as variation of
inhibition efficiency for time and temperature. Weight loss measurement reveals the
maximum efficiency of 71.47% at ½ hours immersion time in 1000 ppm inhibitor
concentration at 18 oC. The 1000 ppm inhibitor can work up to a temperature of 55 oC
with 50% efficiency. The open-circuit potential (OCP) measurement reveals the
extract as a mixed type of inhibitor. From the potentiodynamic polarization
measurement results, the inhibition efficiency of the extract for MS was 93.73% and
75% in the 1000 ppm of inhibitor concentration for as-immersed and immersed
conditions respectively. The adsorption isotherm and thermodynamic parameters
support that the process is spontaneous and endothermic.
Description
Keywords
Shorea robusta, Extract, Green Inhibitors, Mild steel, Weight loss, Polarization