Process improvements for the supercritical in situ transesterification of carbonized algal biomass

Robert B. Levine, Alexandra Bollas, Phillip E. Savage

Research output: Contribution to journalArticlepeer-review

32 Scopus citations

Abstract

This work focuses on the production of biodiesel from wet, lipid-rich algal biomass using a two-step process involving hydrothermal carbonization (HTC) and supercritical in situ transesterification (SC-IST). Algal hydrochars produced by HTC were reacted in supercritical ethanol to determine the effects of reaction temperature, time, ethanol loading, water content, and pressure on the yield of fatty acid ethyl esters (FAEE). Reaction temperatures above 275. °C resulted in substantial thermal decomposition of unsaturated FAEE, thereby reducing yields. At 275. °C, time and ethanol loading had a positive impact on FAEE yield while increasing reaction water content and pressure reduced yields. FAEE yields as high as 79% with a 5:1 ethanol:fatty acid (EtOH:FA) molar ratio (150. min) and 89% with a 20:1 EtOH:FA molar ratio (180. min) were achieved. This work demonstrates that nearly all lipids within algal hydrochars can be converted into biodiesel through SC-IST with only a small excess of alcohol.

Original languageEnglish (US)
Pages (from-to)556-564
Number of pages9
JournalBioresource technology
Volume136
DOIs
StatePublished - May 2013

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Environmental Engineering
  • Renewable Energy, Sustainability and the Environment
  • Waste Management and Disposal

Fingerprint Dive into the research topics of 'Process improvements for the supercritical in situ transesterification of carbonized algal biomass'. Together they form a unique fingerprint.

Cite this