Use of Absorbers Based on Starch for the Effluent Treatment of Dyeing Liquors

The effluents of textile dyeing have presented a permanent problem. The treatment of liquors containing reactive dyestuff hydrolysates is especially difficult. The objective of the researches presented here was to investigate, whether starch products can be used as absorbing materials for the decolourising of such hydrolysate effluents. Native starch shows only a low absorbing capacity for reactive dyestuff hydrolysate. But cationic modified starch products are suitable in principle for the decolourising of reactive dyestuff hydrolysates, and they show the desired effect in the treatment of effluents containing direct dyestuffs, too. The absorbing performance of the used commercial cationic modified starch products can reach thereby - in dependence on the liquor parameters - the order of active charcoal.