Thermal Depolymerization of Lignin

Lignin can be considered as a clean source of renewable energy, which may be a substitute to fossil fuel and thus reduce some of the environmental pollution. This paper presents a review of the thermal process of depolymerization of lignin; which results in production of oil and gaseous fuels from such important renewable energy source. Also, thermal hydro-cracking of lignin enhances the liquefaction of other solid fossil fuels such as coal, by producing intermediates which then react further with coal producing lower molecular weight material, which is more desirable.