Determination of Volatile Fuel Oxygenates in Water by Gas Chromatography–Triple Quadrupole Mass Spectrometry: Effect of Automated Sample Preparation Techniques

Considering the adverse effects of gasoline additives and aromatic compounds on the quality of the water supply and the ecological environment of the water, a methodology, with short chromatographic separation time (22.5 min) and high separation quality, was optimized for the determination of 11 common gasoline additives and aromatic compounds using gas chromatograph coupled with triple quadrupole mass spectrometer (GC–QqQ–MS/MS) system. The extraction procedure of analytes was performed by headspace solid–phase microextraction (HS–SPME) and purge and trap (P&T), respectively. Both of the two extraction methods provided excellent chromatographic resolution in subsequently GC–QqQ–MS/MS detection system, with the coefficients of linear regression of the calibration curves with HS–SPME and P&T pretreatments were 0.9965~0.9998 and 0.9961~0.9999, respectively, n = 7. The limit of detections (LODs) of these selected oxygenate compounds were discovered to be 0.52~32 ng/L in the P&T–GC–QqQ–MS/MS detection system and 0.11~151 ng/L in the HS–SPME–GC–QqQ–MS/MS detection system. For benzene, toluene, ethylbenzene and xylene isomers (BTEX), the HS–SPME–GC–QqQ–MS/MS system provided outstanding detection performance because of the lower LOD obtained. However, for other selected compounds, the P&T–GC–QqQ–MS/MS system offered lower LODs. The proposed extraction–detection procedure is a simple and sensitive analytical approach for the detection of gasoline additives and aromatic compounds in water.

New Catalytic Approaches for Producing Alternative to MTBE Additives for Reformulation of Gasoline

Due to the lead phase out that began in 1973, refiners had to replace the octane loss in gasoline. For this purpose, oxygenates and highly branched alkylates will play a major role as gasoline additives because they have relatively high octane ratings. Methyl tertiary-butyl ether (MTBE) is the oxygenate as a gasoline additive the most widely used nowadays in most of the countries in the world. It is used to raise octane levels, enhance engine performance, improve combustion efficiency and to reduce emissions of air pollutants such as carbon monoxide and hydrocarbons.