Inhibition Effect of 1-Butyl-4-Methylpyridinium Tetrafluoroborate on the Corrosion of Copper in Phosphate Solutions

Table 4

Thermodynamic activation parameters for copper in 0.5 M PO⁴³⁻ solutions in the absence or presence of 10.0 mM of 1-Butyl-4-methylpyridinium tetrafluoroborate (4MBPBF₄) for pH 2 and 4.

Inhibitor	pH	𝐸𝑎 (kJ mol^−1)	Δ𝐻𝑎 (kJ mol^−1)	Δ𝑆𝑎; (J mol^−1 K^−1)
Blank	2	16.64	13.98	−282.65
4MBPBF4		25.66	22.98	−261.19
Blank	4	18.47	15.81	−297.69
4MBPBF4		31.02	28.33	−249.59