title: The role of the reactor wall in hydrothermal biomass conversions.
abstract: The processing of renewable feedstocks to platform chemicals and, to a lesser degree, fuels is a key part of sustainable development. In particular, the combination of lignocellulosic biomass with hydrothermal upgrading (HTU), using high temperature and pressure water (HTPW), is experiencing a renaissance. One of the many steps in this complicated process is the in-situ hydrogenation of intermediate compounds. As formic acid and related low-molecular-weight oxygenates are among the species generated, it is conceivable that they act as a hydrogen source. Such hydrogenations have been suggested to be catalyzed by water, by bases like NaOH, and/or to involve "reactive/nascent hydrogen". To achieve the temperatures and pressures required for HTU, it is necessary to conduct the reactions in high-pressure vessels. Metals are typical components of their walls and/or internal fittings. Here, using cyclohexanone as a model compound for more complex biomass-derived molecules, iron in the wall of high-pressure stainless steel reactors is shown to be responsible for the hydrogenation of ketones with low-molecular-weight oxygenates acting as a hydrogen source in combination with water.
authors.affiliation: School of Chemistry, The University of Sydney, NSW 2006, Australia.
authors.forename: Viktória
authors.initials: V
authors.lastname: Fábos
authors.forename: Alexander K L
authors.initials: AK
authors.lastname: Yuen
authors.forename: Anthony F
authors.initials: AF
authors.lastname: Masters
authors.forename: Thomas
authors.initials: T
authors.lastname: Maschmeyer
mesh_terms: D018533:Biomass; D003512:Cyclohexanones / Q000737:chemistry; D005561:Formates / Q000737:chemistry; D006358:Hot Temperature; D006865:Hydrogenation; D010084:Oxidation-Reduction; D011312:Pressure; D014867:Water / Q000737:chemistry
chemical_list: D003512:Cyclohexanones; D005561:Formates; D014867:Water; C030544:formic acid; C036468:cyclohexanone