Details

Title:

Catalytic Depolymerisation and Conversion of Kraft Lignin to Liquid Products Using Near-Critical Water

Author(s):

Nguyen, T.D.H., Maschietti, M., Åmand, L.-E., Theliander, H., Vamling, L., Olausson, L., Andersson, S.-I.

Document(s):

Abstract:

A small high­pressure pilot plant has been developed in order to study the conversion of LignoBoost Kraft lignin to bio­oil and chemicals in water at near­critical conditions (350 °C, 25 MPa). The chemical conversion takes place in a fixed­bed catalytic reactor (500 cm3) filled with zirconia pellets. Lignin (mass fraction of approximately 5.5 %) is dispersed in aqueous solution containing dissolved potassium carbonate (varied from 0.4 % to 2.2 %), acting as homogeneous co­catalyst, and phenol (approximately 4.1 %), used as co­solvent. The plant operates in continuous mode, with a feed flow rate of 1 kg/h (reactor residence­time 11 min), and the reaction mixture is recirculated internally at approximately a rate of 10 kg/h. The products consist of an aqueous phase, containing phenolic chemicals, and a bio­oil, which could be further processed to transportation fuels or chemicals. The water soluble chemicals in the aqueous phase after acidification were identified through mass spectrometry, showing that the main lignin­derived monomeric compounds are cresols, guaiacols, and catechols, with alkyl side chains of methyl and ethyl type only. Water content in the bio­oil and char deposited on the catalyst after each run are also quantified.

Keywords:

bio-oil, catalytic conversion, lignin, LignoBoost, hydrothermal conversion, near-critical water

Topic:

R&D on Biomass Conversion Technologies for Heating, Electricity and Chemicals

Subtopic:

Pyrolysis and other biomass liquefaction technologies

Event:

21st European Biomass Conference and Exhibition

Session:

2BO.7.2

Pages:

485 - 493

ISBN:

978-88-89407-53-0

Paper DOI:

10.5071/21stEUBCE2013-2BO.7.2

Price:

FREE