IDENTIFICATION OF ORGANIC RESIDUES IN TERTIARY EFFLUENTS BY GC EI-MS,GC/CI-MS AND GC/TSQ-MS/

A method was developed for the analysis of non-volatile dissolved orga nic residues in tertiary treated wastewater effluents. This method inv olved concentration of samples by rotary evaporation, propylation usin g propanol/formic acid/acetyl chloride, and separation, detection and quantitation by capillary GC/EI and CI-MS and GC/TSQ-MS analysis. Ethy lenediamine tetraacetic acid (EDTA) was the most prominent compound fo und in both granular activated carbon (GAG) and chlorinated GAC efflue nts (110 and 140 mu g/L, respectively). Other compounds identified inc luded nitrilotriacetic acid (NTA), carboxyalkylphenoxy ethoxy carboxyl ates, poly(propoxy), poly(ethoxy) or poly(ethoxy)(propoxy) compounds, small aliphatic dicarboxylic acids and aldehydes, all at mu g/L levels . Approximately 80% of all chromatographically separated compounds wer e positively or tentatively identified. The identified compounds are e stimated to account for approximately 10% of the dissolved organic car bon.