This paper provides a short review on recent advances in production of renewable energy through thermochemical processes followed by upgrading techniques such as hydrodeoxygenation, esterification, and steam reforming. Pyrolysis, gasification, and hydrothermal liquefaction have been the main processes of interest for the production of biomass energy for the past decades. However several challenges such as high capital cost due to high energy utilization for thermal processes and hydrogen consumption make these processes less competitive with the existing fossil fuel energy. Further processing of the raw bio-oil is required to improve its fuel properties such as energy density, octane number, and oxygen content. A comprehensive detail on the catalytic cracking, hydrodeoxygenation (HDO), esterification, supercritical extraction and steam reforming processes are reviewed. The major key barriers seem to be high hydrogen consumption and catalyst deactivation during HDO process as the most effective upgrading technique. Notable progresses have been made in the field of catalyst development for HDO process in past few years that can potentially make biomass-energy technology more competitive with traditional fossil fuels.
Sharifi, Mohammad Sadra, "Biomass-Derived Renewable Energy: Prospective Pathways and Key Barriers to Advanced Bio-Fuels" (2018). Civil and Environmental Engineering Student Research. Paper 11.