Optimized production conditions and activation of biochar for effective promotion of long-chain fatty acid degradation in anaerobic digestion

Takuro Kobayashi; Hidetoshi Kuramochi

doi:10.1016/j.biortech.2022.127393

Optimized production conditions and activation of biochar for effective promotion of long-chain fatty acid degradation in anaerobic digestion

Bioresour Technol. 2022 Aug:358:127393. doi: 10.1016/j.biortech.2022.127393. Epub 2022 May 28.

Authors

Takuro Kobayashi¹, Hidetoshi Kuramochi²

Affiliations

¹ Material Cycles Division, National Institute for Environmental Studies, Tsukuba 305-8506, Japan. Electronic address: kobayashi.takuro@nies.go.jp.
² Material Cycles Division, National Institute for Environmental Studies, Tsukuba 305-8506, Japan.

PMID: 35636674
DOI: 10.1016/j.biortech.2022.127393

Abstract

Engineered biochar production and utilization in anaerobic digestion (AD) potentially overcome its limited application to the treatment of slowly degradable or inhibitory substrates. Here an attempt was made to develop an optimized biochar production procedure for use in AD to stimulate palmitic acid biodegradation via direct interspecies electron transfer (DIET). The electrical conductivity of biochar was greatly increased with an elevated pyrolysis temperature and K₂CO₃ activation, and the conductivity reached a comparable level (0.6-1.4 S/cm) to that of carbon black at 800 °C. In addition, the K₂CO₃ activation greatly improved biochar wettability. When using K₂CO₃-activated biochar produced at 800 °C, the maximum methane production rate from palmitic acid was 1.3 times that of a control without biochar addition.

Keywords: Anaerobic digestion; Biochar; Direct interspecies electron transfer; Long-chain fatty acid; Pyrolysis.

MeSH terms

Anaerobiosis
Bioreactors*
Charcoal
Methane*
Palmitic Acid

Substances

biochar
Charcoal
Palmitic Acid
Methane