As can be seen, all DECMC(2:1) except the FB150 dye were lower
than 1.5, which is the maximum value accepted by the quality control
of mill. It is important to highlight that FB150 is an anthraquinone
dye, with a compact aromatic ring structure, which may
interact with the residual compounds of the permeate. FY and
FM showed DECMC(2:1) close to 1.5, mainly due to DL and DH values.