Interesting Behavior of Pachycormus discolor Leaves Ethanol Extract as a Corrosion Inhibitor of Carbon Steel in 1 M HCl: A Preliminary Study

Table 4

Polarization resistance values for carbon steel in 1 M HCl at different temperatures obtained by electrochemical measurements in the absence and presence of EEPD in various concentrations.

Inhibitor concentration (%) v/v	Temperature (°C)	Polarization resistance (Ω)	Inhibition efficiency (%)
Blank	23	43.865
	40	17
	60	5.16
	75	2.067
0.005	23	68.22	35.70
	40	21.03	19.14
	60	6.008	14.11
	75	2.989	30.86
0.01	23	85.60	48.70
	40	31.07	45.28
	60	7.346	29.75
	75	3.174	34.87
0.1	23	99.88	56.08
	40	32.19	47.18
	60	8.353	38.22
	75	3.395	39.11
0.5	23	153.6	71.44
	40	34.86	51.23
	60	9.527	45.83
	75	4.591	54.97
1.0	23	236.2	81.42
	40	101.4	83.23
	60	19.54	73.59
	75	5.56	62.82
2.0	23	620.2	92.95
	40	574.4	97.00
	60	148.4	96.52
	75	115.5	97.89