Determination of Phenolic Groups in Bio-Oils Using Revised Folin-Ciocalteu Methods: Single Cuvette and Plate Reader. Laboratory Analytical Procedure (LAP), Issue Date: May 12, 2022

Phenol components are ubiquitous in wood-derived bio-oils and biocrudes. Their reaction with other functional groups (e.g., aldehydes) may contribute to the formation of carbonaceous species and the expected thermal instability of pyrolysis oils. During hydrotreating, phenols can be recalcitrant species, requiring higher reaction temperatures than other oxygen-containing functional groups. Phenols are also present in upgraded products and have been shown to lead to catalyst deactivation during hydrotreating. They also are the first oxygenated functional group to re-appear in the upgraded product, signaling catalyst deactivation. This procedure covers the determination of phenolic compounds in fast pyrolysis oils. This Laboratory Analytical Procedure (LAP) includes two methods, the first allowing for shorter analysis time at increased reaction temperature, while the second employs a longer analysis time but at room temperature. Additionally, the use of both a single cuvette and of a plate reader are also presented.