Submitted to: American Association Of Textile Chemists And Colorists Review
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 7, 1995
Publication Date: N/A
Interpretive Summary: The dyeing of cotton fabrics results in the generation of highly colored wastewater. The textile industry needs an effective and inexpensive method to decolorize their wastewater. We have examined the potential of using a chemically-modified agricultural byproduct, sugarcane bagasse, for the treatment of textile wastewater containing a commonly employed kind of dye, ,a reactive dye. It was demonstrated that the modified bagasse effectively removed this dye under the salt and pH conditions used to apply the dye to cotton. The low cost of this material allows the bagasse to be used just once, avoiding the need to regenerate the adsorbent. The expended bagasse and adsorbed dye can then be disposed of safely and inexpensively by compositing. This indicates that the modified bagasse provides an excellent means by which textile dyeing operations may recycle or discharge clean water.
Technical Abstract: Currently available procedures for treating wastewaters containing reactive dye are either very costly or environmentally unsound. An ion-exchange resin can be prepared from sugarcane bagasse, a lignocellulosic byproduct of sugarcane processing, that effectively and inexpensively decolorizes dyehouse wastewater in an environmentally benign manner. Bagasse quaternized with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride and cross-linked with epichlorohydrin has an anion-exchange capacity of 1.65 milliequivalents per g of resin when reacted under optimal conditions. Bagasse-derived resin binds hydrolyzed reactive dye with high affinity. The rate of dye binding is inversely proportional to resin particle size. Dye binding is largely unaffected by high salt concentrations. The materials cost (i.e., bagasse plus chemicals) for making the resin is quite low. Thus, it may be economically feasible to use the bagasse-derived resin without regeneration, in a batch process, which would provide great flexibility in the dyehouse wastewater treatment regimen with minimal capital expenditure.