Fast Species-selective Screening for Organolead Compounds in Gasoline by Multicapillary Gas Chromatography With Microwave-induced Plasma Atomic Emission Detection

Abstract

Multicapillary GC is proposed and optimized as a tool for the introduction of gasoline samples into an MIP atomic emission spectrometer for the fingerprinting and species-selective analysis for organolead additives. The coupling of multicapillary GC with MIP-AES not only allows speciation of alkyllead but is also faster than analysis for total lead in gasoline by flame AAS or ICP-AES. All five tetraalkyllead species (Me_nEt_4–nPb,n=1–4) are baseline separated and quantified within 10 s in comparison with about 10–20 min required by conventional GC procedures. Separation is carried out in the isothermal mode but neither resolution nor sample capacity is sacrificed in comparison with conventional capillary GC with oven temperature gradient programming. The throughput reaches about 100 samples h^–1. The detection limit is below 1 µg l^–1 and the linearity range spans four concentration decades. The method was validated by the analysis of the NIST SRM 2715 (Lead in Fuel) reference material.