Mission: Mastery of the ability to reconfigure all partially reduced carbon from plant cell walls into desired molecules is our target—not only “no carbon left behind” but also “a place for every carbon and every carbon in its place.”
Cross-links among plant cell wall biopolymers generate nanoscale architectures and distinct mesoscale domains that have dramatically different properties than those observed in mixtures of biopolymers. C3Bio research indicates that the disparity between theoretical and actual yields of liquid hydrocarbons and high-value chemicals is a consequence of this structural complexity. We must learn to predict, design, and control the molecular interactions between biological polymers in cell walls and between catalysts and cell wall polymers. C3Bio now proposes to develop critical systems-level understanding of how biomass structural complexity at molecular, nanoscale, and mesoscale levels (1) impacts the yields and selectivities of desired reaction products from catalytic and pyrolytic transformations.
Our research challenges two assumptions. First, because plant cell walls are among the most complex structures found in Nature, why do we assume that the complexity is essential for the organism’s viability? Transgenic poplar still grows normally even if its lignin has been modified to contain a single monolignol (2-4). Second, just because existing chemical catalysts are often poisoned by adventitious impurities, why do we assume that catalytic transformations can only be efficient with highly pure streams of molecules? In a major C3Bio breakthrough, we have developed a catalyst that disassembles lignin within intact biomass and converts it to only two aromatic products in high yield (5). We propose to establish the fundamental science required to modulate cell wall complexity and catalytically transform intact biomass in order to gain unprecedented control of effective routing of carbon: we will specify both the structures within, and the reaction products from, lignocellulosic biomass.
- U. S. Department of Energy (2012) From Quanta to the Continuum: Opportunities for Mesoscale Science. Report from Basic Energy Sciences Advisory Committee.
- Franke R, McMichael CM, Meyer K, Shirley AM, Cusumano JC, Chapple C (2000) Modified lignin in tobacco and poplar plants over-expressing the Arabidopsis gene encoding ferulate 5-hydroxylase. Plant J. 22:223-234.
- Huntley SH, Ellis D, Gilbert M, Chapple C, Mansfield SD (2003) Significant increases in pulping efficiency in C4H-F5H-transformed poplars: Improved chemical savings and reduced environmental toxins. J. Agric. Food Chem. 51:6178-6183.
- Mansfield SD, Kang KY, Chapple C (2012) Designed for deconstruction–poplar trees altered in cell wall lignification improve the efficacy of bioethanol production. New Phytol. 194:91-101.
- Parsell T, Yohe S, Degenstein J, Jarrell T, Klein I, Gencer E, Heweston B, Hurt M, Kim JI, Choudhari H, Saha B, Meilan R, Mosier N, Ribeiro F, Delgass WN, Chapple C, Kenttämaa HI, Agrawal R, Abu-Omar MM (2015) A synergistic biorefinery based on catalytic conversion of lignin first from whole lignocellulosic biomass. Green Chemistry.