3.2. Mechanism of dye loading and chelate formation on
dye-loaded materials
The application of a reactive dye onto a cellulose polymer
takes place by the reaction of −Cl group of the monochlorotriazine
reactive system of the dye with the hydroxyl group,
mainly the primary, of the cellulose macromolecule, binding
it covalently under alkaline conditions as shown in Fig. 1
[24].
The reactive dye selected in the present work contains an
azo linkage and the groups like OH are in positions (O, O)
to the azo linkage, a situation favourable for chelate formation
with a metal ion. Due to this specific structure, the metal ion
can form a stable six membered ring chelate, as shown in