A Revisit to the Corrosion Inhibition of Aluminum in Aqueous Alkaline Solutions by Water-Soluble Alginates and Pectates as Anionic Polyelectrolyte Inhibitors

Table 6

Some kinetic parameters from Freundlich isotherm model for corrosion of Al in alkaline media. [OH⁻] = 4.0 and I = 4.0 mol dm⁻³.

Inhibitor	Temp. (°C)	Δ𝐺^∘ads kJ mol^−1	Slope (𝑛)	𝐾ads dm^3 mol^−1	𝑅^2
Alginate	30	−7.38	0.45	0.36	~0.99
	35	−7.87	0.38	0.41	~0.99
	45	−8.57	0.30	0.51	~0.98
Pectates	30	−8.15	0.31	0.48	~0.99
	35	−8.45	0.27	0.52	~0.99
	45	−8.79	0.25	0.53	~0.98