(2023) Bioresource Technology_Low-temperature biochar production from torrefaction for wastewater treatment: A review

Sheng-Lun Lin a, Hongjie Zhang b, Wei-Hsin Chen c,d,e,*, Mengjie Song b, Eilhann E. Kwon f

(Elsevier Ltd) Bioresource Technology ISSN: 9608524 Vol.365 Issue. Article No.128153 DOI: 10.1016/j.biortech.2022.128153

Biochar, a carbon-rich and por ous material derived from waste biomass resources, has demonstrated tremendous
potential in wastewater treatment. Torrefaction technology offers a favorable low-temperature biochar production
method, and torrefied biochar can be used not only as a solid biofuel but also as a pollutant adsorbent.
This review compares torrefaction technology with other thermochemical processes and discusses recent advancements
in torrefaction techniques. Additionally, the applications of torrefied biochar in wastewater treatment
(dyes, oil spills, heavy metals, and emerging pollutants) are comprehensively explored. Many studies have
shown that high productivity, high survival of oxygen-containing functional groups, low temperature, and low
energy consumption of dried biochar production make it attractive as an adsorbent for wastewater treatment.
Moreover, used biochar’s treatment, reuse, and safe disposal are introduced, providing valuable insights and
contributions to developing sustainable environmental remediation strategies by biochar.

The authors would like to acknowledge the financial support of the Environmental Protection Administration Taiwan, R.O.C., under the grant number EPA112F055, and National Science and Technology Council, Taiwan, R.O.C., under the grant numbers NSTC 112-2218-E-006-025- and NSTC 112-2218-E-002-052- for this research. This research was also supported in part by Higher Education Sprout Project, Ministry of Education to the Headquarters of University Advancement at National Cheng Kung University (NCKU).