Pyrolysis oil, also known as bio-oil or bio-crude, is a type of liquid biofuel produced from the thermal decomposition of organic materials in the absence of oxygen, a process known as pyrolysis. Here's a detailed description of pyrolysis oil: Composition: Organic Compounds: Pyrolysis oil is composed of a complex mixture of water, organic compounds, and a variety of chemicals such as phenols, aldehydes, ketones, and acids. The exact composition can vary depending on the feedstock used and the conditions of the pyrolysis process. Water Content: It typically contains a significant amount of water (20-30% by weight), which can influence its properties and handling. Aqueous Phase: It often includes an aqueous phase with dissolved organic compounds and other impurities. Properties: Density: It usually has a higher density compared to conventional fuels, often ranging from 1.1 to 1.3 g/cm³. Viscosity: Pyrolysis oil is generally more viscous than traditional fuels, which can pose challenges for its use in engines and burners without further treatment. pH: It is typically acidic, with a pH ranging from 2.5 to 3.5. Heating Value: The heating value (energy content) is lower than that of fossil fuels, usually around 16-22 MJ/kg, compared to about 42-47 MJ/kg for diesel. Production: Feedstocks: Common feedstocks include agricultural residues, forestry residues, municipal solid waste, and other organic materials. Process: The pyrolysis process involves heating the feedstock to high temperatures (typically 400-600°C) in the absence of oxygen. This thermal decomposition breaks down the organic materials into gases, liquids, and char. The liquid phase, which is collected as pyrolysis oil, can be further processed or refined. Uses: Energy Source: Pyrolysis oil can be used as a renewable energy source for power generation or heating, though its high viscosity and acidity often require pretreatment or upgrading. Chemical Feedstock: It can serve as a raw material for producing chemicals and fuels through further processing. Soil Amendment: With appropriate treatment, it can be used as a soil conditioner or additive.