Corrosion Inhibition and Adsorption Properties of Ethanolic Extract of Calotropis for Corrosion of Aluminium in Acidic Media

Table 2

Mass loss data for aluminium in 0.5 N sulfuric acid with ethanolic extract of leaves, latex, and fruit of Calotropis gigantea.

Inhibitor concentration	Mass loss (gm)	Inhibition efficiency (%)	Corrosion rate (mmpy)	Surface coverage (θ)
Uninhibited	1840		33.1
Leaves
0.12	1023	44.40	18.4	0.4440
0.24	851	53.73	15.3	0.5373
0.36	634	65.54	11.4	0.6554
0.48	465	74.72	8.38	0.7472
0.60	327	82.22	5.89	0.8222
Latex
0.12	951	48.31	17.1	0.4831
0.24	833	54.72	15.0	0.5472
0.36	627	65.92	11.3	0.6592
0.48	442	75.97	7.96	0.7597
0.60	316	82.82	5.69	0.8282
Fruit
0.12	1044	43.26	18.8	0.4326
0.24	875	52.44	15.7	0.5244
0.36	653	64.51	11.7	0.6451
0.48	482	73.80	8.68	0.7380
0.60	319	82.66	5.74	0.8266