About this Research Topic
Hydrothermal processing or “Hydrothermal Upgrading (HTUs)” is a promising technology for converting bioresources/biomass into valuable products such as biofuels. In this method, the thermal degradation of biomolecules takes place in water for yielding precious products, e.g., polysaccharides. Those polysaccharides are then further processed into fermentable sugars and subsequently into biofuels. Currently, hot-water and steam pretreatments are widely used to upgrade energy resources for effective enzymatic conversion into fermentable sugars, and an abundance of derivation approaches, for instance, dilute acid, alkali, high-pressure CO2, physicochemical enhancement (e.g., ball milling, ultrasonic), etc. Effective and economic development of hydrothermal pretreatments is still desired and of wide interest.
Typically, polysaccharides in the lignocellulosic biomass are targeted to be converted for a fuel purpose, while the 15-30% residue lignin is treated as waste. Pyrolysis is a potential way for processing the lignin residues into bio-oil, however, the resulted oil suffers with low heating value and easy condensation. This is due to the rich phenol structures in the lignin-derived fuels. At present, researchers are exploring new hydrothermal technologies to upgrade the lignin-derived fuels, e.g., hydrogenation. This may completely solve the drawbacks of lignin-derived fuels and therefore change their fate.
This Research Topic aims at publishing selected and novel research contributions on the hydrothermal conversion of bioresources to energy and fuels. Corresponding research about energy production, technology innovation, and environmental assessment will be applicable. The bioresources described here could come from agriculture, forestry, food processing/catering industry, etc. The Topic Editors particularly welcome Original Research and Review manuscripts regarding the utilization of bioresource wastes for energy production. Review contributions are expected to present sound critical overviews of state-of-the-art topics. The potential themes include, but are not limited to:
• Updated hydrothermal technologies for producing energy and fuels;
• Hydrogenation technologies for processing bioresources to liquid fuels;
• Hydrothermal gasification of bioresources for energy and fuels;
• Hydrothermal carbonization of bioresources for solid fuels;
• Supercritical treatments for bioresource energy upgrading;
• Development of hydrothermal/steam pretreatments for sugars as energy resources;
• Catalyst study in the hydrothermal conversion of bioresources to energy and fuels;
• Environmental assessment of the process, or the converted energy, e.g. life cycle assessment (LCA).
Keywords: hydrothermal, bioresource, bioenergy, sustainable development, life cycle assessment (LCA)
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.