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

Table 1

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

Inhibitor concentration	Mass loss (gm)	Inhibition efficiency (%)	Corrosion rate (mmpy)	Surface coverage (θ)
Uninhibited	1840		33.1
Leaves
0.12	1012	45.00	18.2	0.4500
0.24	872	52.60	15.7	0.5260
0.36	653	64.51	11.7	0.6451
0.48	487	73.53	8.77	0.7353
0.60	348	81.08	6.27	0.8108
Latex
0.12	987	46.35	17.7	0.4635
0.24	856	53.47	15.4	0.5347
0.36	641	65.16	11.5	0.6516
0.48	465	74.72	9.43	0.7472
0.60	313	82.98	5.64	0.8298
Fruit
0.12	1026	44.23	18.4	0.4423
0.24	898	51.19	16.1	0.5119
0.36	674	63.36	12.1	0.6336
0.48	465	74.72	8.38	0.7472
0.60	338	81.63	6.09	0.8163