DYESTUFFS FOR IMPROVED METAL ADSORPTION FROM EFFLUENTS

Reactive dyestuffs, widely used for dyeing cellulosic textiles, have been subjected to a novel use. Cheap cellulose-containing materials, such as bamboo pulp and sawdust, have the capacity to adsorb heavy metal ions, and this is enhanced further on dyeing these substrates with reactive dyes of the monochlorotriazine type. Almost complete removal of metal ions such as Cu2+, Pb2+, Hg2+, Fe2+, Fe3+, Zn2+, and Ni2+ from their aqueous solutions has been achieved. The role of the dyestuff in improving the metal ion adsorption is discussed.