초록 |
Pharmaceuticals can be harmful to ecosystems even at trace concentration levels and be considered as emerging contaminants. We investigated the microbial sludge and competing ions in actual wastewaters from sewage treatment plants on sorptive behaviors of pharmaceuticals by a strong cation exchange resin (CER), Dowex50W4-200. As model pharmaceuticals, four tricyclic antidepressants (TCAs) were used: amitriptyline, imipramine, clomipramine, and desipramine. The CER showed the outstanding sorption capacity above of the TCAs 95 % removal efficiency with the resin dose of 0.01 g L-1 from artificial wastewater. However, the removal efficiency in the filtered actual wastewater (without solid sludge) decreased by 33-42 % according to the types of the TCAs. This is likely because the competing cations present in the filtered actual wastewater interfere with the adsorption of the TCAs. It was also noticed that microbial sludge could contribute to 3-12 % removal of the TCAs. This study indicates that interference by competing ions and adsorption by microbial sludge should be considered for efficient use of the CER to treat wastewaters contaminated with pharmaceuticals. |