Analysis of Titan tholin pyrolysis products by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry

The reddish brown haze that surrounds Titan, Saturnʹs largest moon, is thought to consist of tholin-like organic aerosols. Tholins are complex materials of largely unknown structure. The very high peak capacity and structured chromatograms obtained from comprehensive two-dimensional GC (GC × GC) are attractive attributes for the characterization of tholin pyrolysis products. In this report, GC × GC with time-of-flight MS detection and a flash pyrolysis inlet is used to characterize tholin pyrolysis products. Identified pyrolysis products include low-molecular-weight nitriles, alkyl substituted pyrroles, linear and branched hydrocarbons, alkyl-substituted benzenes and PAH compounds. The pyrolysis of standards found in tholin pyrolysate showed that little alteration occurred and thus these structures are likely present in the tholin material.