Jump to main content
Jump to site search

Issue 11, 2011
Previous Article Next Article

Pyrolysis oils from CO2 precipitated Kraft lignin

Author affiliations


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 CO2 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 CO2 method (pH 10.5 and 9.5). The CO2 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 (∼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 CO2 precipitated lignin for pyrolysis and subsequent liquid biofuel production.

Graphical abstract: Pyrolysis oils from CO2 precipitated Kraft lignin

Back to tab navigation

Publication details

The article was received on 08 Jul 2011, accepted on 08 Sep 2011 and first published on 10 Oct 2011

Article type: Paper
DOI: 10.1039/C1GC15818J
Citation: Green Chem., 2011,13, 3196-3202
  •   Request permissions

    Pyrolysis oils from CO2 precipitated Kraft lignin

    M. Kosa, H. Ben, H. Theliander and A. J. Ragauskas, Green Chem., 2011, 13, 3196
    DOI: 10.1039/C1GC15818J

Search articles by author