Dielectric and physico-chemical behavior of single thermally thick wood blocks under microwave assisted pyrolysis

• DOI: 10.1016/j.partic.2023.07.004
• Publication Date: 2023-07-23T17:31:55Z
• Authors: Nicole Vorhauer-H...; Jakob Seidenbecher; Supriya Bhaskaran; Francesca Schenkel; Lucas Briest; Suresh Gopalkrishna; Jan Barowski; Andrea Dernbecher; Liane Hilfert; Ilona Rolfes; Alba Dieguez-Alonso
• Keywords: Pyrometer; Inert; Microwave oven; Inert gas

Pyrolysis of thermally thick beech wood blocks with a size around 2.5 × 8 6 cm3 (width length height) was carried out in lab scale microwave reactor frequency 2.45 GHz, operated, both, at 300 W and 600 under inert conditions, using N2 400 mbar absolute pressure. The cavity had 20 cm3. specific energy supply referred to the untreated block 4–8 W/g, slight variations depending on initial water content. mass loss reflected power were in-situ monitored during experiments. sample surface chamber temperatures measured pyrometer thermocouple, respectively. Physico-chemical dielectric properties produced solids investigated compared those chars conventional pyrolysis same raw materials. It is shown that complex permittivity solid products changed drastically process, increasing heating as conversion process evolved. This easily achieved without susceptors. However, not enough achieve high degree, independently irradiation time. This, together physico-chemical analyses solids, hinted importance transport kinetics materials, although further investigation still required.