Analysis of oil shale and petroleum source rock pyrolysis by triple quadrupole mass spectrometry: Comparisons of gas evolution at the heating rate of 10 °C/min

Kimmeridge, Phosphoria, La Luna, Teistberget, New Albany, Janusfjellet, Wenzen, Maoming, Fushun, Woodford, and three Green River oil shales were subjected to programmed-temperature pyrolysis at a heating rate of 10 °C/min using triple-quadrupole mass spectrometry as the detection method. Volatile compound evolution, including hydrocarbons, non-condensible gases, and heteroatomic compounds were monitored by on-line detection. As expected, the temperatures of maximum evolution rate (Tmax) depended on the sample and the species evolving. The Tm a x values for generation of total light volatile organic compounds were between 442 to 472 °C, with the New Albany (eastern U.S. Devonian) giving the lowest values and Brotherson (Green River formation) giving the highest values. The heteroatomic species had Tmax values which were slightly lower than those for hydrocarbon evolution. Non-hydrocarbon gas formation, particularly H2S, CO2, CO, and H2O, was highly dependent upon the mineral matrix and mineral matrix kerogen interactions of the shale.