A Comparative Study of the Inhibitory Effect of the Extracts of Ocimum sanctum, Aegle marmelos, and Solanum trilobatum on the Corrosion of Mild Steel in Hydrochloric Acid Medium

Table 4

Impedance parameters for the corrosion of mild steel in 1N HCl in the absence and presence of various concentrations of the plant extracts at 30°C.

Name of the plant extract	Conc. of extract (% in v/v)	𝑅𝑡 (Ω cm^2)	𝐶dl (μF/cm^2)	Inhibition efficiency (%)
Blank	—	7.58	285.34
Ocimum sanctum	2.0	110.91	19.34	93.2
	4.0	253.86	8.44	97.0
	6.0	358.80	6.00	97.9
	8.0	274.99	7.95	97.2
	10.0	239.25	9.02	96.8
Aegle marmelos	2.0	69.85	31.09	89.1
	4.0	88.41	24.52	91.4
	6.0	136.49	15.86	94.4
	8.0	224.80	9.62	96.6
	10.0	208.34	10.25	96.4
Solanum trilobatum	2.0	18.62	116.02	59.3
	4.0	27.34	79.00	72.3
	6.0	37.12	58.35	79.6
	8.0	48.31	44.72	84.3
	10.0	87.86	24.52	91.4