Study of Temperature Effect on the Corrosion Inhibition of C38 Carbon Steel Using Amino-tris(Methylenephosphonic) Acid in Hydrochloric Acid Solution

Table 2

Corrosion kinetic parameters for C38 steel in 1 M HCl in absence and presence of different concentrations of ATMP.

Concentration (M)	𝐸a; (kJ mol^−1)	Δ𝐻a; (kJ mol^−1)	Δ𝑆a; (J mol^−1 k^−1)	𝐸a−Δ𝐻a (kJ mol^−1)
Blank	22.92	20.28	−125.22	2.64
5 × 10^−5	24.98	22.34	−119.84	2.64
5 × 10^−3	48.90	46.26	−48.05	2.64
5 × 10^−2	55.25	52.62	−31.04	2.63
1 × 10^−1	58.75	56.11	−22.43	2.64