Selective Production of Value-Added Chemicals from Fast Pyrolysis of Lignocellulosic Biomass: Current Status, Challenges and Prospects

Abstract

Fast pyrolysis of biomass remains one of the most promising technologies for the sustainable production of value-added chemicals. This thermally driven process typically maximizes liquid yield through strategic implementation of high heating rates combined with rapid vapor quenching, thus effectively suppressing secondary polycondensation and cracking reactions. However, the resultant product spectrum comprises over 400 oxygenated compounds with characteristically low individual concentrations. To achieve high-yield selective production of target chemicals, coordinated optimization of both biomass composition/structure and pyrolysis parameters is essential. This comprehensive approach integrates pretreatment methodologies, reactor design optimization, and precise control of operational variables (temperature, heating rate, vapor residence time), supplemented by catalytic interventions. This review systematically examines the mechanistic foundations of biomass fast pyrolysis, including decomposition pathways of cellulose, hemicellulose, and lignin, with particular emphasis on factors governing their pyrolysis selectivity. Special attention is given to catalytic strategies enabling targeted production of value-added chemicals, such as levoglucosan, levoglucosenone, 1,4:3,6-dianhydro-α-D-glucopyranose, 1,5-anhydro-4-deoxy-D-glycero-hex-1-en-3-ulose, 1-hydroxy-3,6-dioxabicyclo[3.2.1]octan-2-one, 5-hydroxymethylfurfural, furfural, phenols, and aromatics. Critical analysis of catalyst design principles and associated reaction mechanisms provides new insights into selective pyrolysis control. The review concludes with an assessment of persistent technological barriers and commercialization potential for biomass-derived chemical production via selective fast pyrolysis.