Size exclusion chromatography (SEC) with multiple detectors: a powerful tool in treatment process selection and performance monitoring

The traditional application of size exclusion chromatography (SEC) with single wavelength UV detection (at 254 nm) for molecular weight (size) estimation can be expanded to include multiple detectors that provide insight into the size, structure, and functionality of natural organic matter (NOM). Other detectors include, foremost, on-line dissolved organic carbon (DOC) as well as fluorescence and variable wavelength UV. SEC coupled with this range of detectors elucidates unique signatures for different types and sources of NOM including allochthonous versus autochthonous (i.e., algal organic matter (AOM)) versus wastewater effluent (i.e., effluent organic matter (EfOM)). Also revealed by SEC are preferential NOM removals and/or transformations by various water and wastewater treatment processes as well as identification of problematical NOM components (e.g., membrane foulants).