Pyrolyseöl

Pyrolyseöl, commonly referred to as bio-oil, is the liquid product obtained from fast pyrolysis of biomass in the absence of oxygen. The process involves rapidly heating biomass to around 450 °C in a short residence time, followed by quick quenching. The main products are bio-oil, non-condensable gases, and char. Typical yields from fast pyrolysis are about 60–75% bio-oil, with the remainder split between char and gas, depending on feedstock and process conditions.

Feedstocks used for pyrolyseöl include wood, agricultural residues, and other lignocellulosic materials. The resulting oil is a complex, highly oxygenated mixture containing a large fraction of water and numerous organic compounds such as acyclic acids, aldehydes, ketones, phenolics, sugars, and esters. Its water content is high (often 20–40% by weight), and the oil has high acidity, significant viscosity, and is prone to aging and phase separation.

Due to its chemical composition, pyrolyseöl is not directly interchangeable with fossil fuels. It is typically unstable and corrosive, with storage challenges and a tendency to polymerize over time. Stabilization and upgrading are often required before use as a fuel or chemical feedstock. Upgrading routes include catalytic upgrading and hydrodeoxygenation to produce a more stable, hydrocarbon-rich oil or fuels compatible with refinery streams.

Applications range from energy production (co-firing or dedicated boilers) to serving as a feedstock for refining into transport fuels or platform chemicals. Life-cycle impacts depend on feedstock, process energy intensity, and upgrading efficiency. Pyrolyseöl remains a focus of research and development to improve stability, yield, and integration with existing energy systems.