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Labs & Instruments

The Environmental Science laboratories provide innovative facilities for teaching and research at the Colorado College. The following information includes specific information regarding the primary instruments utilized in EV. If you'd like to use these instruments for your research or would like samples processed, please contact Darren Ceckanowicz. Funding for these facilities was generously provided by the Kresge Foundation.

Elemental analysis

Elemental AnalysisThe ThermoQuest NC2100 measures the relative abundance of C, H, N, and S in environmental samples. The instrument combusts small samples (2-20 mg) in the presence of high-purity oxygen, oxidizes the combustion products in a chromium trioxide column, reduces the oxides with a reduced copper column, drys the sample via manganese perchlorate, separates the analytes with a chromatography column, then detects the separated components with a thermal conductivity detector. All analytes are passed through the system by ultra-high purity helium. In EV the instrument is primarily utilized to measure C/N ratios in soils and biological materials (aquatic insects, terrestrial plants, bone powders).

Gas chromatography - mass spectrometry (GC-MS)

GCMSThe HP 6890/5973 GC-MS analyzes the absolute concentrations of organic molecules in liquids and gases by injection of the sample onto a chromatography column. An inert carrier gas then transports the sample through the column and separates the molecules based on their relative affinity for the column substrate (more interactions, slower transport) and the column conditions (e.g., temperature, flow rate). In this case, the separated molecules are then detected by a flame ionization detector, an electrical conductivity detector, or a mass spectrometer. The mass spectrometer consists of an ionization source, a quadrupole mass analyzer, and an electron multiplier detector. In EV this instrument is primarily used for VOC analysis of atmospheric samples and organic contaminant concentrations in liquids. The Environmental Program now has two GC-MS systems for organic and gas phase analyses.

Atmospheric analysis

Atmospheric AnalysisThe Entech air preconcentrator system is designed to extract and transfer air samples collected within 6L stainless steel canisters. First, canisters are cleaned at 100C with repeated evacuation and ultra-high purity nitrogen. Following sample collection, the canisters are attached to a manifold and extracted onto a Tenex trap at liquid nitrogen temperatures. The trapped sample is then heated and transferred to the GC-MS for analysis. In EV these instruments are primarily used for atmospheric VOC analyses, including the BTEX compounds (benzene, toluene, ethylbenzene, and xylene).\

Ion analysis

Ion AnalysisThe Dionex IC determines the concentration of major ions in solution by ion chromatography, separating the primary anions and cations due to their relative affinity with an ion exchange resin. A small volume of solution is isolated by a multiport valve and carried to the column by an eluent. The ions are separated at high pressures and carried to a suppressor membrane, which eliminates the eluent conductivity by ion exchange across a porous membrane. The remaining analytes are then detected by an electrochemical detector. In EV the IC is used to determine major cation (K, Na, Mg, Ca) and anion (Cl, SO4, PO4, NO3, F, Br) concentrations in stream water and soil extracts.

 

The Environmental Program recently acquired a new Waters Acquity Ultra Performance Liquid Chromatography system for the rapid analysis of polar organic compounds. This will be utilized by both EV and Chemistry faculty for both class experiments and their research programs. For example, Howard Drossman's Arctic soils study will be completed on this new instrument.