Table 2:
Inhibition efficiency, corrosion rate, and surface coverage for aluminium in 1 N and 2 N hydrochloric acid solution with given inhibitor addition for 24 h at 298 ± 1 K.
Conc. Inh (%)
Inhibition efficiency
Corrosion rate
Surface coverage
Inhibition efficiency
Corrosion rate
Surface coverage
(1 N)
(1 N)
(1 N)
(2 N)
(2 N)
(2 N)
Pet. Ether extract
0.12
29.44
50.47
0.2944
88.61
30.43
0.8861
0.24
44.96
39.37
0.4496
88.77
29.99
0.8877
0.36
46.57
38.21
0.4657
89.74
27.40
0.8974
0.48
55.61
35.33
0.5561
91.68
22.21
0.9168
0.60
54.03
32.88
0.5403
92.66
19.61
0.9266
Acetone extract
0.12
25.81
53.06
0.2581
61.72
102.24
0.6172
0.24
28.63
51.05
0.2863
64.36
95.17
0.6436
0.36
39.11
43.55
0.3911
91.63
22.35
0.9163
0.48
57.86
30.14
0.5786
93.30
17.88
0.9330
0.60
73.39
19.03
0.7339
98.27
4.61
0.9827
Methanol extract
0.12
11.90
63.01
0.1190
49.30
135.40
0.4930
0.24
20.28
57.10
0.2028
54.27
122.14
0.5427
0.36
34.68
46.72
0.3468
58.80
110.02
0.5880
0.48
38.51
50.47
0.3851
62.09
101.23
0.6209
0.60
49.60
36.05
0.4960
67.12
87.82
0.6712