(501e) On the Synergy between Non-Thermal and Thermal Catalytic Deconstruction of Waste Lignocellulosic Materials

In the recent years, lignin valorization has gained upward momentum owing to advances in both plant bioengineering and catalytic processing of lignin. In this new horizon, catalysis is now applied to the ‘pulping process’ itself, creating efficient methods for lignocellulose fractionation or deconstruction (here referred to as Catalytic Upstream Biorefining or ‘CUB’). These processes render, together with delignified pulps, lignin streams of low molecular weight (M_w) and low molecular diversity. Recently, we introduced a CUB process based on Early-stage Catalytic Conversion of Lignin (ECCL) through H-transfer reactions catalysed by Raney Ni. This approach renders a lignin stream obtained as a viscous oil, comprising up to 60 wt% monophenolic compounds (M_w <250 Da). The remaining oil fraction (40%) is mainly composed of lignin oligomers, and as minor products, holocellulose-derived polyols and lignin-derived species of high M_w(0.25-2 kDa). Simultaneously, the process yields a holocellulose pulp with low content of residual lignin (<5%).

In this contribution, the contribution of non-thermal catalytic biomass deconstruction to thermal biorefining will be presented, outlining future perspectives in this emerging field of research.