(2020) Environmental Science and Technology_Using CO₂ as an Oxidant in the Catalytic Pyrolysis of Peat Moss from the North Polar Region

Lee T., Jung S., Hong J., Wang C.-H., Alessi D.S., Lee S.S., Park Y.-K., Kwon E.E.

(American Chemical Society) Environmental Science and Technology ISSN: 0013936X Vol.54 Issue.10 Article No. DOI: 10.1021/acs.est.0c01862

As global warming and climate change become perceived as significant, the release of greenhouse gases (GHGs) stored in the earth's polar regions is considered a matter of concern. Here, we focused on exploiting GHGs to address potential global warming challenges in the north polar regions. In particular, we used CO₂ as a soft oxidant to recover energy as syngas (CO and H₂) and to produce biochars from pyrolysis of peat moss. CO₂ expedited homogeneous reaction with volatile matters from peat moss pyrolysis, and the mechanistic CO₂ role resulted in the conversion of CO₂ and peat moss to CO at ≥530 °C. Steel slag waste was then used as an ex situ catalyst to increase reaction kinetics, addressing the issue of the role of CO₂ being limited to ≥530 °C, with the result where substantial H₂ and CO formation was achieved at a milder temperature. The porosity of biochars, a solid peat moss pyrolysis product, was modified in the presence of CO₂, with a significant improvement in CO₂ adsorption capacity compared to those achieved by N₂ pyrolysis. Therefore, CO₂ has the potential to serve as an initial feedstock in sustainable biomass-to-energy applications and biochar production, mitigating atmospheric carbon concentrations. © 2020 American Chemical Society.

This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT) (NRF-2019R1A4A1027795, NRF-2019H1D3A1A01070644, NRF-2019H1A2A1076293, and NRF-2016M1A5A1901769 (KOPRI-PN20081)).