Purge & Trap

Gas chromatography is one of the fundamental analytical tools that compose the modern analytical lab, along with Mass Spectroscoy, Spectroscopy and Microscopy. However, like everything else, it does have several limitations, including lack of sensitivity, inability to tolerate water injections, and the sample must be in the vapor state. These limitations all come into play when studying aqueous samples in drinking and waste water and beverages.

Purge and Trap, invented in the 60s in response to the Clean Water Act, is the most effective method to answer these challenges for extracting and concentrating volatile organic compounds (VOC) from liquids and solids. The Purge and Trap process involves purging the sample with an inert gas in a sealed environment (sparge vessle) at the appropriate temperature. The gas going through the sample will establish thermal equilibrium with VOCs in the sample, therefore transferring the VOCs from an aqueous state to a vapor. After eliminating the moisture through the wet trap, the gas is then swept to an analytical trap that absorbs and retains the VOCs , where they are transferred to the Gas Chromatograph for further analysis.

​CDS analytical instruments are designed around a few core concepts including EPA regulation compliance, reliability, expandability, dependability and competitive pricing. It has been acknowledged as the industry workhorse for decades. To further unleash the full power of your GC systems, we designed a full suite of products including standalone autosamplers (8500 series) and an industry first Purge and Trap tool for the popular CTC PAL systems.

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Genetec is a member of the same family of companies as Kovalent. Both companies share the same set of values and are in many ways integrated with each other. The main difference between the two companies are their products. Kovalent is involved in system solutions including instrumentation and Genetec is mainly working with consumables. The focus of Genetec is chromatography accessories. You are welcome to visit their state of the art web shop: genetec.se