Data on corrosion inhibition effect of Stylosanthes gracilis extract on UNS S30403 austenitic stainless steel in dilute acid solution

Abstract This article presents data on the evaluation of Stylosanthes gracilis extract as corrosion inhibitor for 304 L in H2SO4 solution. The data were obtained from weight loss measurements, energy dispersive spectroscopy and X-ray diffraction studies. The extract reduced the rate of corrosion on SS 304l in H2SO4 solution at an optimum concentration of 1.2 g/L with inhibition efficiency of about 87.81% and corresponding surface coverage of 0.878. The corrosion rate of 0.232 mm/yr was observed in the inhibited sulphuric acid as against 1.904 mm/yr in the blank acid respectively at 240 h of exposure of the specimens. At 2400 h of exposure, the observed corrosion rate was 0.228 mm/yr with an efficiency of 74.21%. Whereas the extract's efficacy was slightly influenced by time, concentration has a profound effect on the extract's protection capability. The decrease in the efficiency of the extract after 2400 h is 13.6% suggesting the good stability with time.