Fast Pyrolysis of Pine Wood Pretreated by Large Pilot-Scale Thermomechanical Refining for Biochemical Production

• Published in: Industrial & engineering chemistry research 2020-12, Vol.59 (49), p.21294-21304
• Main Authors: Torr, Kirk M, de Miguel Mercader, Ferran, Murton, Karl D, Harbers, Thije J. M, Cooke-Willis, Martin H, van de Pas, Daniel J, Suckling, Ian D
• Format: Article
• Language: English
• Subjects: Applied Chemistry
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.0c04734

Pretreatments of lignocellulosic biomass prior to fast pyrolysis need to give a better yield and quality of pyrolysis oil and be practical to implement at a commercial scale. This study demonstrated, at a large pilot scale, that thermomechanical refining can reduce the particle size, hemicellulose content, and mineral content of pine wood chips, leading to improved yields of carbohydrate-derived chemicals on fast pyrolysis. Additionally, a hemicellulose-rich byproduct can be generated during the pretreatment for separate valorization. The impact of different presteaming times, citric acid infusion, and disc refining on the yield and composition of the pyrolysis oil was studied. Presteaming of citric acid-infused wood chips at 173 °C for 3 min and refining to wood fiber proved most effective in improving the yield of pyrolysis oil organics, including the valuable biochemicals levoglucosan and hydroxyacetaldehyde, while reducing the yields of low-value char and noncondensable gases.