pyrolyseGCMS

Pyrolyse GC-MS, also known as pyrolysis-GC-MS or py-GC-MS, is an analytical technique used to characterize complex organic materials that are non-volatile or thermally inert. In this method, a small sample is heated in a pyrolyzer under an inert atmosphere to generate volatile fragments from the material. The fragments are carried by a gas stream into a gas chromatograph, where they are separated on a capillary column. The separated compounds enter a mass spectrometer, where they are ionized and detected, providing mass spectra used for identification. The combination of retention time and mass spectra allows identification of monomers, additives, and degradation products, enabling inference about the original material's composition.

Pyrolysis temperature and ramp rate are critical parameters and depend on the material studied; typical temperatures range from 500 to 1000°C for polymers, often with rapid, short-time heating to minimize secondary reactions. The technique is destructive but rapid and requires small sample sizes.

Applications include identification of polymers and plastics in unknown samples, analysis of inks and varnishes in art conservation, characterization of bituminous materials and asphalts, forensic analysis of seized materials, and studies of biochar and environmental samples. Data interpretation relies on spectral libraries and characteristic pyrolysis products, sometimes complemented by reference materials or standards.

Limitations include potential artefacts due to pyrolysis conditions, difficulty in quantification, and the need for careful method development. Py-GC-MS remains a powerful tool for rapid, structural insights into complex organic materials.