||Fate of Water Soluble Azo Dyes in the Activated Sludge Process.
Shaul, G. M. ;
Dempsey, C. R. ;
Dostal, K. A. ;
Holdsworth, T. J. ;
||Environmental Protection Agency, Cincinnati, OH. Risk Reduction Engineering Lab.
Azo dyes ;
Sulfonic acids ;
Activated sludge process ;
Mass balance calculations
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||The objective of the study was to determine the partitioning of water soluble azo dyes in the activated sludge process (ASP). Azo dyes are of concern because some of the dyes, dye precursors, and/or their degradation products such as aromatic amines (which are also dye precursors) have been shown to be, or are suspected to be, carcinogenic. Specific azo dyes were spiked at 1 and 5 mg/L to pilot-scale treatment systems with both liquid and sludge samples collected. Samples were analyzed by high performance liquid chromatography (HPLC) with an ultraviolet-visible detector. Mass balance calculations were made to determine the amount of the dye compound in the waste activated sludge (WAS) and in the activated sludge effluent (ASE). Of the 18 dyes studied, 11 compounds were found to pass through the ASP substantially untreated, 4 were significantly adsorbed onto the WAS, and 3 were apparently biodegraded.
||Pub. in Chemosphere, v22 n1-2 p107-119 1991. See also PB88-208251.
|NTIS Title Notes
||Reprint: Fate of Water Soluble Azo Dyes in the Activated Sludge Process.
||PC A03/MF A01