Applications of subcritical and supercritical water conditions for extraction, hydrolysis, gasification, and carbonization of biomass: a critical review

Lachos-Perez, D.; Brown, A.B.; Mudhoo, A.; Martinez, J.; Timko, M.T.; Rostagno, M.A.; Forster-Carneiro, T.

doi:10.18331/BRJ2017.4.2.6

Applications of subcritical and supercritical water conditions for extraction, hydrolysis, gasification, and carbonization of biomass: a critical review

Document Type : Review Paper

Authors

D. Lachos-Perez ¹

A.B. Brown ²

A. Mudhoo ³

J. Martinez ¹

M.T. Timko ²

M.A. Rostagno ⁴

T. Forster-Carneiro ¹

¹ Department of Food Engineering, University of Campinas (UNICAMP), Rua Monteiro Lobato, n.80, 13083-862 Campinas, SP, Brazil.

² Department of Chemical Engineering, Worcester Polytechnic Institute, 100 Institute Road, Goddard Hall 123. Worcester MA 01609, United States of America (USA).

³ Department of Chemical and Environmental Engineering, Faculty of Engineering, University of Mauritius, Réduit 80837, Mauritius.

⁴ School of Applied Sciences, University of Campinas, R. Pedro Zaccaria, 1300, 13484-350, Limeira, SP, Brazil.

10.18331/BRJ2017.4.2.6

Abstract

This review summarizes the recent essential aspects of subcritical and supercritical water technology applied to
the extraction, hydrolysis, carbonization, and gasification processes. These are clean and fast technologies which do not need pretreatment, require less reaction time, generate less corrosion and residues, do not use
toxic solvents, and reduce the synthesis of degradation byproducts. The equipment design, process parameters, and types of biomass used for subcritical and supercritical water process are presented. The benefits of catalysis to improve process efficiency are addressed. Bioactive compounds, reducing sugars, hydrogen, biodiesel, and hydrothermal char are the final products of subcritical and supercritical water processes. The present review also revisits advances of the research trends in the development of subcritical
and supercritical water process technologies.

Graphical Abstract

Applications of subcritical and supercritical water conditions for extraction, hydrolysis, gasification, and carbonization of biomass: a critical review

Highlights

Advances of research trends in development of subcritical and supercritical water processes technologies are reviewed.

Essential aspects of sub- and supercritical water applied to extraction, hydrolysis, carbonization and gasification processes are discussed.

Equipment design, process parameters, and types of biomass used for sub- and supercritical water process are presented.

Bioactive compounds, reducing sugars, hydrogen, biodiesel, and hydrothermal char are the final products of sub- and supercritical water processes.

Keywords

Biomass

Subcritical water

Supercritical water

Waste-to-Energy

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