Structural characterization of birch lignin isolated from a pressurized hot water extraction and mild alkali pulped biorefinery process

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: L. Lagerquist, A. Pranovich, A. Smeds, S. von Schoultz, L. Vähäsalo, J. Rahkila, I. Kilpeläinen, T. Tamminen, S. Willför, P. Eklund
Förläggare: Elsevier
Publiceringsår: 2018
Tidskrift: Industrial Crops and Products
Tidskriftsakronym: Ind. Crops Prod.
Volym: 111
Artikelns första sida, sidnummer: 306
Artikelns sista sida, sidnummer: 316
Antal sidor: 11
ISSN: 0926-6690
eISSN: 1872-633X


Abstrakt

In this work we have characterized a mild soda pulped birch (betula pendula) lignin after a novel pressurized hot water extraction pilot process. In the process hemicelluloses are first isolated from woods chips with hot water at oxygen-starved conditions, followed by mild alkali pulping at oxygen-starved conditions to remove lignin from the cellulose. Lignin was precipitated, washed and fractionated from the black liquor and characterized by quantitative C-13 NMR, C-13 DEPT experiments, P-31 NMR, 2D HSQC, FTIR, size exclusion chromatography (SEC), elemental analysis, pyrolysis-gas chromatography-mass spectrometry (py-GC-MS), methoxyl group quantification and residual carbohydrate analysis after methanolysis. The structure was compared to a MWL of birch obtained from the same wood chips and the differences were an increase in phenolic hydroxyl groups, carboxylic groups, polydispersity index, and reduction of aliphatic hydroxyl groups. The process resulted in beta-O-4 cleavage and condensation of the structure. This lignin is therefore suitable to be used in its polymeric form, rather than for degradation of the structure to small building blocks.


Nyckelord

Aryl glycerol, Birch lignin, Condensed structures, lignin characterization, Milled wood lignin

Senast uppdaterad 2019-06-12 vid 04:30