title: Biobased alkylphenols from lignins via a two-step pyrolysis - Hydrodeoxygenation approach.
abstract: Five technical lignins (three organosolv, Kraft and soda lignin) were depolymerised to produce monomeric biobased aromatics, particularly alkylphenols, by a new two-stage thermochemical approach consisting of dedicated pyrolysis followed by catalytic hydrodeoxygenation (HDO) of the resulting pyrolysis oils. Pyrolysis yielded a mixture of guaiacols, catechols and, optionally, syringols in addition to alkylphenols. HDO with heterogeneous catalysts (Ru/C, CoMo/alumina, phosphided NiMO/C) effectively directed the product mixture towards alkylphenols by, among others, demethoxylation. Up to 15wt% monomeric aromatics of which 11wt% alkylphenols was obtained (on the lignin intake) with limited solid formation (<3wt% on lignin oil intake). For comparison, solid Kraft lignin was also directly hydrotreated for simultaneous depolymerisation and deoxygenation resulting in two times more alkylphenols. However, the alkylphenols concentration in the product oil is higher for the two-stage approach. Future research should compare direct hydrotreatment and the two-stage approach in more detail by techno-economic assessments.
authors.affiliation: Energy Research Centre of the Netherlands (ECN), Biomass & Energy Efficiency, Westerduinweg 3, 1755 LE Petten, The Netherlands. Electronic address: dewild@ecn.nl.
authors.forename: P J
authors.initials: PJ
authors.lastname: de Wild
authors.affiliation: Energy Research Centre of the Netherlands (ECN), Biomass & Energy Efficiency, Westerduinweg 3, 1755 LE Petten, The Netherlands.
authors.forename: W J J
authors.initials: WJ
authors.lastname: Huijgen
authors.affiliation: Chemical Engineering, ENTEG, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Kloekhorst
authors.affiliation: Chemical Engineering, ENTEG, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: R K
authors.initials: RK
authors.lastname: Chowdari
authors.affiliation: Chemical Engineering, ENTEG, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: H J
authors.initials: HJ
authors.lastname: Heeres
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D001709:Biotechnology / Q000379:methods*; D002384:Catalysis; D002396:Catechols / Q000737:chemistry; D006139:Guaiacol / Q000737:chemistry; D008031:Lignin / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*
chemical_list: D002396:Catechols; D010636:Phenols; D006139:Guaiacol; C076151:Kraft lignin; D008031:Lignin; D000537:Aluminum Oxide
keywords: Alkylphenols; Aromatics; Hydrodeoxygenation; Lignin; Pyrolysis