Reuse of Effluent Water Obtained in Ultrafiltration of Reactive Dyes.

The Reactive Black 5 and Reactive Red dyestuffs have been synthesized in the laboratory. The synthesis was obtained by diazotization of 1-amino-phenyl-4-beta hydroxyethyl sulfone sulfate ester and coupling with 1-amino-8-hydroxynaphthalene-3,6-disulfonic acid (H-acid) (mole ratio 2:1) (Reactive Black 5Na) and (mole ratio 1:1) (Reactive Red Na). The dye was purified-concentrated by ultrafiltration technology and the permeate (waste) was used as dye bath in the exhaustion of cotton and polyamide with the sodium salt of Reactive Black 5 (RB5Na) and the sodium salt of Reactive Red (RRNa). The same dyeing was also made with fresh water as dye bath. Fastness properties were also measured in both cases and the results were compared. Color measurement results of the dyeings were almost the same when the waste as dye bath was used. [ABSTRACT FROM AUTHOR]