3. The thermochemical route

The thermochemical or BTL (Biomass To Liquid) route refers to the process of upgrading lignocellulosic biomass through gasification and subsequent synthesis. The end product can be diesel, DME (dimethyl ether), methanol or ethanol. It owes its name to the gasification reaction, which combines thermal and chemical processes at high temperatures (> 800°C). Among other things, it produces hydrogen (H ₂ ) and carbon monoxide (CO) which, in a subsequent process step, are upgraded to liquid hydrocarbons (C _x H _y O _z ). While the step of converting synthesis gas (CO + H ₂ ) into hydrocarbons is well mastered industrially, particularly in GTL (Gas To Liquid) processes, biomass...