(2019) Bioresource Technology_Orange peel valorization by pyrolysis under the carbon dioxide environment

Kwon D., Oh J.-I., Lam S.S., Moon D.H., Kwon E.E.

(Elsevier Ltd) Bioresource Technology ISSN: 9608524 Vol.285 Issue. Article No.121356 DOI: 10.1016/j.biortech.2019.121356

To valorize biomass waste, pyrolysis of orange peel was mainly investigated as a case study. In an effort to establish a more sustainable thermolytic platform for orange peel, this study particularly employed CO₂ as reactive gas medium. Accordingly, this study laid great emphasis on elucidating the mechanistic role of CO₂ in pyrolysis of orange peel. The thermo-gravimetric analysis (TGA) confirmed that no occurrence of the heterogeneous reactions between the solid sample and CO2. However, the gaseous effluents from pyrolysis of orange peel experimentally proved that CO₂ effectively suppressed dehydrogenation of volatile matters (VMs) evolved from the thermolysis of orange peel by random bond scissions. Moreover, CO₂ reacted VMs, thereby resulting in the formation of CO. Note that the formation of CO was being initiated at temperatures ≥550 °C. The two identified roles of CO₂ led to the compositional modification of pyrolytic oil by means of lowering aromaticity. © 2019 Elsevier Ltd

This work was supported by a grant from National Research Foundation of Korea (NRF-2017R1D1A1B03028176).