Process characteristics for microwave assisted hydrothermal carbonization of cellulose

Junting Zhang; Ying An; Aiduan Borrion; Wenzhi He; Nan Wang; Yirong Chen; Guangming Li

doi:10.1016/j.biortech.2018.03.010

Process characteristics for microwave assisted hydrothermal carbonization of cellulose

Bioresour Technol. 2018 Jul:259:91-98. doi: 10.1016/j.biortech.2018.03.010. Epub 2018 Mar 6.

Authors

Junting Zhang¹, Ying An², Aiduan Borrion³, Wenzhi He⁴, Nan Wang⁴, Yirong Chen⁵, Guangming Li⁶

Affiliations

¹ College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Department of Civil, Environmental and Geomatic Engineering, University College London, Gower Street, London WC1E 6BT, UK.
² Shanghai Shendi Institute, Shanghai 200120, China.
³ Department of Civil, Environmental and Geomatic Engineering, University College London, Gower Street, London WC1E 6BT, UK.
⁴ College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
⁵ College of Natural Resources, University of California, Berkeley, 260 Mulford Hall, CA 94704, USA.
⁶ College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: ligm@tongji.edu.cn.

PMID: 29536879
DOI: 10.1016/j.biortech.2018.03.010

Abstract

The process characteristics of microwave assisted hydrothermal carbonization of cellulose was investigated and a first order kinetics model based on carbon concentration was developed. Chemical properties analysis showed that comparing to conventional hydrothermal carbonization, hydrochar with comparable energy properties can be obtained with 5-10 times decrease in reaction time with assistance of microwave heating. Results from kinetics study was in great agreement with experimental analysis, that they both illustrated the predominant mechanism of the reaction depend on variations in the reaction rates of two co-existent pathways. Particularly, the pyrolysis-like intramolecular dehydration reaction was proved to be the predominant mechanism for hydrochar generation under high temperatures. Finally, the enhancement effects of microwave heating were reflected under both soluble and solid pathways in this research, suggesting microwave-assisted hydrothermal carbonization as a more attracting method for carbon-enriched hydrochar recovery.

Keywords: Cellulose decomposition; Hydrochar; Kinetics study; Microwave-assisted hydrothermal carbonization; Process analysis.

MeSH terms

Carbon*
Cellulose*
Hot Temperature
Kinetics
Microwaves*

Substances

Carbon
Cellulose