Effective evaluation of catalytic deoxygenation for in situ catalytic fast pyrolysis using gas chromatography–high resolution mass spectrometry

•New Py-GC–MS method using dopant-assisted atmospheric pressure chemical ionization.•Direct chemical composition analysis regardless of their presence in the database.•Effective evaluation of catalytic fast pyrolysis for cellulose biomass.•Partial information about reaction mechanisms in catalytic deoxygenation.

Effective deoxygenation in catalytic fast pyrolysis (CFP) is crucial for bio-oil stabilization and its successful commercialization. Herein, we utilize a new analytical platform that couples gas chromatography (GC) to dopant-assisted atmospheric pressure chemical ionization (dAPCI) time-of-flight mass spectrometry (TOF MS) to evaluate catalytic deoxygenation of cellulose pyrolysis. Soft ionization and accurate mass measurement through dAPCI-TOF MS allows direct chemical composition analysis of GC-separated molecules, regardless of their presence in the database. The analytical approach was successfully demonstrated for its ability to evaluate catalytic efficiency of different catalysts and to monitor the change in CFP reaction products with catalyst-to-biomass load ratio. A total of 142 compounds could be analyzed with this approach compared to 38 compounds in traditional Py-GC-EI-MS analysis.