Lignocellulosic biomass presents a promising source of renewable carbon that can enable the sustainable generation of fuels, chemicals, and consumer goods that power our modern economy.^1,2 While the feasibility of processing the cellulose and hemicellulose fractions of native biomass has been demonstrated, economical utilization of the lignin-containing fraction is more challenging³ due to it's chemical complexity, source-dependent structural variability, and recalcitrant nature.^4,5 However, recent advances in reductive catalytic fractionation (RCF) processes have enabled clean separation of a small set of lignin monomers from the cellulose and hemicellulose fractions of native biomass, which, in turn, simplifies downstream approaches to converting these reaction products into more valuable chemicals.^6,7

In this work, we investigate the potential economic feasibility of using electrocatalytic reactors, as compared to traditional thermochemical reactors, to upgrade lignin monomers to cycloalkyl and aromatic species, specifically targeting benzene, toluene, and xylene (BTX). To this end, we developed a process-based techno-economic model to quantify the viability of electrochemical upgrading, to benchmark materials and reactor performance requirements, and to identify potential technical hurdles. Furthermore, we investigate the model sensitivity to critical process parameters and key assumptions. This analysis enables a direct comparison between traditional thermochemical hydrogenation processes and proposed electrochemical hydrogenation processes across multiple installation scales as well as potentially favorable combinations of the two approaches. We hope that the results presented here inspire further research into electrochemical approaches to enable biomass upgrading.

References:

(1) Werpy, T.; Petersen, G. Top Value Added Chemicals from Biomass Volume I—Results of Screening for Potential Candidates from Sugars and Synthesis Gas; Department of Energy, 2004.

(2) Holladay, J. E.; Bozell, J. J.; White, J. F.; Johnson, D. Top value-added chemicals from biomass; Department of Energy: Pacific Northwest National Labs, 2007.

(3) Rinaldi, R.; Schüth, F. Energy Environ. Sci. 2009, 2 (6), 610.

(4) Vassilev, S. V.; Baxter, D.; Andersen, L. K.; Vassileva, C. G. Fuel 2010, 89 (5), 913.

(5) Zakzeski, J.; Bruijnincx, P. C. A.; Jongerius, A. L.; Weckhuysen, B. M. Chem. Rev. 2010, 110 (6), 3552.

(6) Bosch, S. V. den; Schutyser, W.; Vanholme, R.; Driessen, T.; Koelewijn, S.-F.; Renders, T.; Meester, B. D.; Huijgen, W. J. J.; Dehaen, W.; Courtin, C. M.; Lagrain, B.; Boerjan, W.; Sels, B. F. Energy Environ. Sci. 2015, 8 (6), 1748.

(7) Anderson, E. M.; Katahira, R.; Reed, M.; Resch, M. G.; Karp, E. M.; Beckham, G. T.; Román-Leshkov, Y. ACS Sustain. Chem. Eng. 2016, 4 (12), 6940.