L. nigrescens and D. antarctica samples were collected in the bay
of Valparaíso, Chile. After sampling, the algae sample was washed
in tap water and then in distilled water to remove any salt present.
Then the adsorbent was dried at 50 C until they had a constant
weight. The dried alga D. antarctica was cut into pieces of 0.5–
1 cm length and the dried alga L. nigrescens was cut into pieces
of 1–1.5 cm length and 0.5–1 cm diameter (only the stipe of this
algae was used). These sizes of the algae were chosen based on a
practical approach, since the handling and later use in a real treatment
process should be feasible.