(2021) Journal of Cleaner Production_Strategic way for valorization of manure into chemicals and fuels

Cho S.-H., Jung S., Tsang Y.F., Lin K.-Y.A., Jeon Y.J., Kwon E.E.

(Elsevier Ltd) Journal of Cleaner Production ISSN: 9596526 Vol.322 Issue. Article No.129109 DOI: 10.1016/j.jclepro.2021.129109

Animal manure contains a variety of organic materials that can be used for synthesis of value-added biofuels and chemicals. To maximize the carbon recovery from animal manure waste, this study focused on consecutive valorization of horse manure into furfural and syngas (H₂ and CO). Acid hydrolysis/dehydration of horse manure was employed to extract furfural, and the residue after furfural extraction was valorized into syngas and bio-oil through CO₂-assisted pyrolysis. In acid treatment process, the levulinic acid and furfural were produced from horse manure, and the maximum yield (3.68 wt%) of furfural was achieved at 0.5 M H₂SO₄ (40 wt% based on hemicellulose content). Horse manure residue was further converted into bio-oil and syngas under N₂/CO₂ environments. Under CO₂ atmosphere, gas phase homogeneous reactions were occurred, which simultaneously reduced CO₂ and oxidized bio-oil showing enhanced CO formation (18 times higher comparing to pyrolysis under N₂). The homogeneous reaction also resulted in decrease of aromaticity in bio-oil. To enhance the reaction kinetics of the homogeneous reaction and thermal cracking of bio-oil under CO₂, catalytic pyrolysis was performed in the presence of Ni/SiO₂ catalysts. The catalytic pyrolysis improved syngas (H₂ and CO) production more than one order of magnitude higher, comparing to pyrolysis without Ni catalyst. All the experimental findings suggested that horse manure and CO₂ could be used as raw materials for production of value-added chemicals and syngas. © 2021 Elsevier Ltd

This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (No. NRF-2019R1A4A1027795 and NRF-2021R1A6A3A13044307 ). Seong-Heon Cho also acknowledges financial support from Hyundai Motor Chung Mong-Koo Foundation .