Trace Analysis of Ethanol, MTBE, and Related Oxygenate Compounds in Water Using Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry

Abstract

Solid-phase microextraction (SPME) and gas chromatography/mass spectrometry have been combined for trace-level determination of very polar compounds in water, including the widely used gasoline oxygenates ethanol and methyl tert-butyl ether (MTBE). A relatively simple extraction method using a divinylbenzene/Carboxen/poly(dimethylsiloxane) SPME fiber was optimized for the routine analysis of ethanol and MTBE in groundwater and reagent water. A sodium chloride concentration of 25% (w/w) combined with an extraction time of 25 min provided the greatest sensitivity while maintaining analytical efficiency. Replicate analyses in fortified reagent and groundwater spiked with microgram per liter concentrations of ethanol and MTBE indicate quantitative and reproducible recovery of these and related oxygenate compounds. Method detection limits were 15 microg L(-1) for ethanol, 1.8 microg L(-1) for tert-butyl alcohol, 0.038 microg L(-1) for tert-amyl methyl ether, 0.025 microg L(-1) for ethyl-tert-butyl ether, and 0.008 microg L(-1) for MTBE.

Influence of Sowing Times, Densities, and Soils to Biomass and Ethanol Yield of Sweet Sorghum

“…Thereby, it should be better replaced by other oxygenated compounds to enhance the octane number of the fuels. Presently, ethanol as an oxygenous biomass fuel is the preferred alternative to MTBE for its biodegradable, low toxicity, persistence, and regenerative characteristics [3]. Ethanol has been produced from various crops such as sweet sorghum (S. bicolor), corn (Zea mays), wheat (Triticum aestivum), barley (Hordeum vulgare), sugar cane (Saccharum officinarum), sugar beet (Beta vulgaris), cassava (Manihot esculenta), and sweet potato (Imopoea batatas) [4].…”

Analysis of tert-Butanol, Methyl tert-Butyl Ether, Benzene, Toluene, Ethylbenzene and Xylene in Ground Water by Headspace Gas Chromatography-Mass Spectrometry

“…Recently, a specific and highly sensitive method for MTBE analysis has been developed that relies on headspace solid phase microextraction (SPME). [11][12][13][14][15][16][17][18][19] The methods have many advantages in it being convenient and having rapid and automatic extraction, but its low recovery due to the volatility and long loading time of the SPME fibre.…”

Determination of MTBE, TBA and BTEX in Soil by Headspace Gas Chromatography-Mass Spectrometry

“…SPME methods in the analysis of BTEX, MTBE and TBA in water have many merits, in which is convenient, rapid, robotic and sensitive. 13,18,19,22 However, the method has the disadvantages in the investigation of contaminated soil because of the sorption competition by frequently found co-contaminants needs to be considered and the limited lifetime of the fiber. Especially, another drawback in the simultaneous investigation method of BTEX, MTBE and TBA in contaminated soil is the limitation of adsorption/partitioning fibers optimal all together to the analytes having various physicochemical properties.…”