Chemical treatment with caustic soda (NaOH)
A quantity of the solid support is mixed with a volume of caustic soda (NaOH) 0,1M with a ratio of 1/5
(weight/volume), left during 24h, and then it was washed with distilled water until neutral pH [18].
After that, it was dried in the drying oven at 105°C until constant weight, the activate banana peel
(ABP) was crushed and filtered with a diameter lower or equal to 0,315 mm.