Vol.:(0123456789) 1 3
Waste and Biomass Valorization
https://doi.org/10.1007/s12649-021-01656-y
SHORT COMMUNICATION
The Application of Enzymatic Pretreatment with Subsequent Pyrolysis
to Improve the Production of Phenols from Selected Industrial
(Technical) Lignins
Bongo M. Majeke
1
· Franҫois X. Collard
1
· Luvuyo Tyhoda
2
· Johann F. Görgens
1
Received: 3 June 2021 / Accepted: 2 December 2021
© The Author(s), under exclusive licence to Springer Nature B.V. 2021
Abstract
Purpose The development of efective strategies for lignin valorization to valuable products is of high interest in various
industries such as pulp and paper and the emerging bioenergy process. Indeed, the successful valorization of lignin could
improve the proftability of these processes and their environmental performance. In this study, an original strategy involving
the sequential application of enzymes and pyrolysis was explored for the conversion (i.e., valorization) of lignins to bio-oil
rich in phenols.
Methods Four technical lignins from diferent processes were pretreated for 24 h using the concerted depolymerization
action of lignin peroxidase and quinone reductase enzymes. Pyrolysis was then performed on the pretreated and untreated
(control) samples using a bench-scale tubular reactor at 550 ℃ for 30 min.
Results Enzymatic pretreatment could contribute to a 17.5–82.3% increase in the bio-oil mass yield during subsequent
pyrolysis. In some cases, enzymatic pretreatment also improved the production of total phenols in bio-oils by a maximum
of 43%, with steam explosion (S-E) lignin showing the best performance. Of the four technical lignins, S-E and soda-
anthraquinone lignins gave the highest production of monomeric phenols whereas the sulfte lignins were more challenging
to valorize due to their high inorganic contents.
Conclusion Enzymatic pretreatment could contribute to the valorization of some technical lignins to phenols during sub-
sequent pyrolysis.
* Bongo M. Majeke
16628233@sun.ac.za
1
Department of Process Engineering, Stellenbosch University,
Private Bag X1, Matieland 7602, South Africa
2
Department of Forestry and Wood Sciences, Stellenbosch
University, Private Bag X1, Matieland 7602, South Africa