Exhaustive removal of anions from aqueous waste via nucleophilic displacement reactions in the presence of phase transfer catalysts

Nucleophilic anions such as phenoxide and cyanide dissolved in an aqueous phase were effectively reacted with alkyl hahdes present in an organic phase containing a phase transfer catalyst. Preliminary data show the concentration of these anions in water decreased from 10,000 ppm to less than 1 ppm in 2-3 h at less than 70 degreesC. This methodology enables treatment of hazardous anions that are difficult to remove when using a conventional approach. (C) 2003 Elsevier B.V. All rights reserved.