Polarization parameters for Al anode in 4 M NaOH electrolyte with and without various concentrations of EDTA-2Na.

C (mM)	E corr (V)	β a (mV dec−1)	−βc (mV dec−1)	i corr (mA cm−2)	CR (mm per year)	η PDP (%)
Blank	−1.397	314.4	203.9	56.92	621.5	—
1	−1.428	340.6	190.7	39.82	434.8	30.0
3	−1.443	342.8	192.8	33.89	370.0	40.4
5	−1.442	318.3	189.3	30.71	335.3	46.0
7	−1.452	252.9	193.3	25.69	280.5	54.9