Chromatography Techniques and Spectrometry

Analytical Techniques in Water Treatment

For assuring the safety of water supplies detailed chemical analysis of water is a prerequisite. To assure water quality and to assess environmental impacts, limitations in our ability helps to identify contaminants in water. The compound range that is amenable to specific identification is due to the recent improvements in analytical techniques having expanded the "analytical window". Much has been learned about the occurrence, fate, and transport of organic chemicals in the environment using these improved tools. "Analytical frontiers" are represented by the boundaries of the analytical window and are continuously expanded. By the contaminant concentration and chemical properties, such as molecular weight, polarity, chemical lability, and structural complexity these boundaries are defined loosely.

In typical natural water samples, compared to the total organic carbon, the mass of compounds that is within the analytical window is small. In conjunction with derivatization, the specifically identified compounds accounted for less than 12 percentage of the organic carbon in different groundwater samples are analysed using coupled Gas Chromatography/Mass Spectroscopy (GC/MS). This fraction typically remains uncharacterized or only in aggregate form for 80 percentage of the total organic carbon. Because of a lack of reference spectra and/or reference compounds, majority of the contaminants that are detected, most remain unidentified and/or unquantified even though good mass spectra are obtained. To propose structures using spectral determinations, the information that can be deduced from the mass spectra may be sufficient. However, because of a lack of reference spectra, verification and quantification of the proposed structures are often impossible.