On the chemical composition and pyrolytic behavior of hybrid poplar energy crops from northern Spain

Short Rotation Woody Coppices (SRWCs) where several tree species and clones grown on marginal land typically over 3-10 year cycles have been recognized as providers of sustainable energy and as feedstocks for producing other fuels and chemicals. A thorough physical and chemical characterization is crucial for understanding and optimizing harvesting and production strategies. Accordingly, this study focuses on the evaluation of chemical and thermochemical features of three parts of harvested shoots (base and middle of the shoot, and branches) of selected hybrid poplars of short rotation -AF2, Beaupré and I214 of 5, 9 and 8 years-old, respectively-. Results show a decrease in the ash content from the top to the base of each species with ash levels always around or below 1 wt%, and at the same time a decrease in high heating value -HHV-. The differences in HHV between the different parts of the hybrid poplars are in good agreement with results obtained from FTIR and thermogravimetric patterns.