Publication

Efficient depolymerization of lignin to biobased chemicals using a two-step approach involving ozonation in a continuous flow microreactor followed by catalytic hydrotreatment

Bernardes Figueiredo, M., Keij, F. W., Hommes, A., Deuss, P. J., Venderbosch, R. H., Yue, J. & Heeres, H., 18-Nov-2019, In : ACS Sustainable Chemistry & Engineering . 7, 22, p. 18384-18394 11 p.

Research output: Contribution to journalArticleAcademicpeer-review

Lignin is a promising feedstock for the replacement of conventional carbon sources for the production of chemicals and fuels. In this paper, results are reported for the depolymerization of various residual lignins in the absence of a catalyst by utilizing ozone. Reactions were performed in a microreactor setup ensuring high gas-liquid mass transfer rates, a low inventory of ozone, and straightforward scale-up possibilities. The ozonation is demonstrated using a representative model compound (vanillin) and various lignins (pyrolytic and organosolv) dissolved in methanol (2.5 wt %). Experiments were performed under ambient conditions, at gas-liquid flow ratios ranging from 30 to 90 and short residence times on the order of 12-24 s. Analyses of the products after methanol removal revealed the presence of (di)carboxylic acids, methyl esters, and acetals. Extensive depolymerization was achieved (i.e., up to 30% for pyrolytic lignin and 70% for organosolv lignins). Furthermore, a two-step approach in which the ozonated lignin is further hydrotreated (350-400 degrees C, 100 bar H-2, 4 h, Pd/C as catalyst) showed a substantial increase in depolymerization efficiency, yielding a 2.5-fold increased monomer yield in the product oil compared to a hydrotreatment step only.
Original languageEnglish
Pages (from-to)18384-18394
Number of pages11
JournalACS Sustainable Chemistry & Engineering
Volume7
Issue number22
Early online date28-Oct-2019
Publication statusPublished - 18-Nov-2019

    Keywords

  • Lignin, Ozone, Oxidation, Microreactor, Hydrotreatment, MASS-TRANSFER CHARACTERISTICS, AEROBIC OXIDATION, MODEL COMPOUNDS, BIO-OIL, BIOREFINERY LIGNIN, ALCOHOL OXIDATION, ACID PRODUCTION, WET OXIDATION, BOND-CLEAVAGE, KRAFT LIGNIN

Download statistics

No data available

ID: 100385169