Fast Pyrolysis of Wood Lignin: Towards A Continuous Process

Lignin is a major element of wood structure and has great potential as a renewable resource of biomass for the production of biofuels and valuable chemicals. Lignin has significant advantages over other biomass sources because it is not in the food supply chain and is an industrial side/by product in the paper and pulp industry as well as the biofuels fermentation industry. Although it exhibits challenges due to it is complex structure, conversion of lignin into biofuels and chemicals has received attention over the years. Most of the work done on lignin pyrolysis until now is limited to research at the analytical level. The nature of lignin molecule makes it difficult to be processed by using conventional fast pyrolysis methods. Therefore, there is a need for the development of a process for the efficient conversion of lignin into fuels and chemicals. In this respect, fast pyrolysis of lignin was studied on bench scale to assess the effects of process parameters such as moisture, feed rate, fluidization gas flow and temperature on the overall conversion and product quality. The viscosity and the average molecular weight of the lignin oil were determined. The liquid product was characterized for the chemical structure identification by employing 13C NMR spectroscopy. Gas components were analyzed and quantified by using gas chromatography.