Pyrolysis oils from CO2 precipitated Kraft lignin
Artikel i vetenskaplig tidskrift, 2011

A common goal in present and future forestry, biofuels and biomaterials practices, is the need to valorize lignocellulose processes to maximize value and optimize autonomic economy. Consequently, a key focus of modern biorefining is the on-site utilization of all residual materials generating products of the highest possible value. The LignoBoost process, recently demonstrated on the pilot-scale at Kraft pulp mills, injects CO(2) into pulping liquors which results in a lower solution pH and thereby precipitates lignin. The present paper compares and evaluates the pyrolysis of pulping liquor lignins precipitated by sulfuric acid (pH 3) and the aforementioned CO(2) method (pH 10.5 and 9.5). The CO(2) based process yielded lignin that showed superior pyrolysis properties including low gas formation and increased bio-oil yields, close to 40%, consisting primarily of low (similar to 150 g mol(-1)) molecular weight compounds. Subsequent NMR analysis showed that the oils exhibit favorable changes in functionalities, e. g. loss of aromatic and gain in aliphatic carbon percentages as well as decrease in carboxyl and methoxyl (oxygen containing) groups. Moreover, NMR results further confirmed previously hypothesized lignin pyrolysis reactions, while at the same time showed the potential of CO(2) precipitated lignin for pyrolysis and subsequent liquid biofuel production.

dimers

ether

nmr-spectroscopy

bio-oils

pathways

model compounds

products

cleavage mechanisms

liquefaction

wood

Författare

M. Kosa

Georgia Institute of Technology

H. X. Ben

Georgia Institute of Technology

Hans Theliander

Chalmers, Kemi- och bioteknik, Skogsindustriell kemiteknik

Wallenberg Wood Science Center (WWSC)

A. J. Ragauskas

Georgia Institute of Technology

Green Chemistry

1463-9262 (ISSN) 1463-9270 (eISSN)

Vol. 13 11 3196-3202

Ämneskategorier

Kemi

DOI

10.1039/c1gc15818j