Characterization of energy-rich hydrochars from microwave-assisted hydrothermal carbonization of coconut shell

Elaigwu, Sunday E.; Greenway, Gillian M.

Abstract

In this study, microwave-assisted hydrothermal carbonization of waste coconut shell (feedstock) is reported. It is a thermo-conversion technique in which the feedstock was transformed into energy-rich carbonaceous material under mild conditions. The process was conducted in a microwave oven by heating the waste coconut shell in deionized water inside a pressurized vessel. The effects of different process conditions on the product yields, and the energy properties of the hydrochars were studied by varying the reaction temperature from 150 to 200 °C and residence time from 5 to 30 min. The results showed that there was transformation of the feedstock in the process due to the decarboxylation, dehydration, and demethanation reactions. This led to changes in the chemical and structural compositions, as well as increase in the energy properties of the prepared hydrochars. The higher heating value increased from 15.06 MJ/kg in the feedstock to 19.76 MJ/kg in the hydrochar. The energy properties of the hydrochars prepared in this study showed that microwave-assisted hydrothermal carbonization process could be a technique for converting waste coconut shell into high value-added product.

Citation

Elaigwu, S. E., & Greenway, G. M. (2019). Characterization of energy-rich hydrochars from microwave-assisted hydrothermal carbonization of coconut shell. Waste and biomass valorization, 10(7), 1979–1987. https://doi.org/10.1007/s12649-018-0209-x

• Journal Article Type: Article
• Acceptance Date: Jan 23, 2018
• Online Publication Date: Feb 8, 2018
• Publication Date: 2019-07
• Deposit Date: Mar 6, 2018
• Publicly Available Date: Feb 9, 2019
• Journal: Waste and Biomass Valorization
• Print ISSN: 1877-2641
• Electronic ISSN: 1877-265X
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 7
• Pages: 1979–1987
• DOI: https://doi.org/10.1007/s12649-018-0209-x
• Keywords: Microwave-assisted; Hydrothermal carbonization; Hydrochar; Coconut shell; Product yields; Energy properties
• Public URL: https://hull-repository.worktribe.com/output/610112
• Publisher URL: https://link.springer.com/article/10.1007/s12649-018-0209-x
• Additional Information: This is a post-peer-review, pre-copyedit version of an article published in Waste and Biomass Valorization.. The final authenticated version is available online at: https://doi.org/10.1007/s12649-018-0209-x