The rise of lignin biorefinery

Lignocellulosic biomass, ranging from softwood to agriculture and forestry wastes, represents the most abundant resource for modern biorefinery. In the course of the last years, we have witnessed the rise of ‘reductive catalytic fractionation’ processes of lignocellulosics in which priority attention is given to lignin that is ‘first’ converted into aromatic feedstocks. This opinion outlines recent advances in the reductive valorization of lignocellulosic biomass via lignin-first biorefinery approach, with particular emphasis on the fundamental catalytic reactions involved in the extraction and depolymerization of lignin and in the stabilization of the obtained phenolic units. Finally, a brief overview on the further transformations of lignin-derived monolignols and phenolics into value-added chemicals, fuels, polymeric materials, and active pharmaceutical ingredients is presented.