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

Table 4

Some kinetic parameters from Langmuir 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	−19.66	1.004	50.38	>0.99
	35	−20.74	1.032	67.80	>0.99
	45	−21.83	1.094	90.91	>0.99
Pectates	30	−21.31	1.042	98.04	>0.99
	35	−22.03	1.006	112.99	>0.99
	45	−23.10	0.984	129.03	>0.99