Perspectives for Thermochemical Conversions of Lignocellulosic Biomass.

Abstract

The biorefinery concept of lignocellulosic biomass with focus on thermochemical conversions will be presented and discussed with respect to the advantages, impacts, and methods. Analytics regarding the reaction mechanisms for the decomposition of cellulose, hemicellulose and lignin, respectively, will be presented along with new trends and perspectives within plasma and catalytic pyrolysis of lignin-fractions, artificial neural networks, hydrothermal liquefaction, torrefaction, gasification and combustion, pyrolysis and hydro pyrolysis as well as supercritical fluids for the catalytic thermochemical conversion of biomass and co-processing of upgraded bio-oil in fluidized catalytic cracking (FCC). A few examples are mentioned at this point; however, more details are given in the respective chapters. Concerning the catalytic conversion of lignin fractions the concept of the "catalyst philosophy" has been adapted from crude oil refining by using the hierarchical pore structure of the catalyst to arrive at the desired final products, like fuelcomponents or phenols. As a consequence, the same hierarchical catalysts can be applied in the co-processing of bio-oil with crude oil refined fractions. As a preliminary conclusion, the thermochemical conversion of lignocellulosic biomass has already reached a certain level of insight and understanding, however, there is still room for improvement and even a better understanding, and, last but not least, an upscaling to an industrial scale remains.