Hydrothermal carbonization (HTC) is a relatively recent technology
that offers the benefits of converting the biomass into
homogenous lignite-like material. In this process, biomass in a
mixture with water is kept during a certain period of time in a
closed vessel in the temperature range of 180–250 ◦C (pressure
corresponding saturated values) . The reaction temperature,
residence time, and water-to-biomass (w/b) mass ratio are
reported to be the main factors to determine the rate of wood components decomposition . Several reaction mechanisms are
involved in biomass decomposition during HTC, such as hydrolysis,
dehydration, decarboxylation, polymerization, and aromatization.
Components of lignocellulosic biomass (lignin, hemicellulose, and
cellulose) become less stable with the presence of water under
saturated conditions .