1 3 Bio-oil from pyrolysis of wood pellets using a microwave multimode 4 oven and different microwave absorbers 5 6 7 Andrea Andrea b , Mamdouh Zaid b,c , Cedric Briens b , Franco Berruti b , Luca Rosi a , Mattia Bartoli a , 8 Marco Frediani a , Piero Frediani a,⇑ 9 a Department of Chemistry ‘‘Ugo Schiff’’, University of Florence, Via della Lastruccia, 13, Sesto Fiorentino 50019, Firenze, Italy 10 b Institute for Chemicals and Fuels from Alternative Resources (ICFAR), Department of Chemical and Biochemical Engineering, Western University, London, ON N6A 5B9, Canada 11 c Natural Resources Canada, Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen Street East, Sault Ste. Marie, ON P6A 5M7, Canada 12 13 14 16 highlights 17 18  Fuel from wood pellets through 19 microwave assisted pyrolysis. 20  Bio-oil from wood pyrolysis were 21 obtained. 22  Different microwave absorbers were 23 successfully used. 24  Char useful as fuel or for carbon 25 sequestration is obtained. 26 graphical abstract 28 28 30 article info 31 Article history: 32 Received 16 June 2014 33 Received in revised form 22 January 2015 34 Accepted 19 February 2015 35 Available online xxxx 36 Keywords: 37 Wood pellets pyrolysis 38 Microwave pyrolysis 39 Bio-oil characterization 40 Beech pellets 41 42 abstract 43 Wood pellets were pyrolyzed using a microwave oven and different microwave power, apparatus set-up 44 and microwave absorbers (none, Fe, and carbon). 45 Pyrolysis was realized in a short time in the presence of Fe or carbon while it was incomplete if the 46 absorber was not present. Furthermore when the absorber was present the shape of the pellets remains 47 unaltered while if the absorber was not employed pellets were disaggregated. 48 Three fractions were collected from each pyrolysis: a gas, a liquid also called bio-oil and a solid called 49 bio-char. The bio-oil collected contained two phases and they were quantitatively characterized through 50 a GC/MS-FID procedure using an internal standard according to a previously reported method. HPLC/MS, 51 FTIR and 1 H NMR spectroscopy were also employed for characterization of these liquids. Cellulose 52 pyrolysis products were present in the upper phase such as water acetic acid, furans (such as furfural), 53 carbohydrates and their derivatives. Compounds from pyrolysis of lignin such as phenols and veratric 54 acid were present in the bottom phase. 55 The microwave assisted pyrolysis showed the possibility to efficiently convert wood pellets in different 56 products. The main economical important components may be separated and used as chemicals, natural 57 drugs or pesticides, while the remaining components, the solid and the gas may be used for energy pro- 58 duction (solid and bio-oil). Solid may be also used for carbon sequestration. 59 Crown Copyright Ó 2015 Published by Elsevier Ltd. All rights reserved. 60 61 62 http://dx.doi.org/10.1016/j.fuel.2015.02.081 0016-2361/Crown Copyright Ó 2015 Published by Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: piero.frediani@unifi.it (P. Frediani). Fuel xxx (2015) xxx–xxx Contents lists available at ScienceDirect Fuel journal homepage: www.elsevier.com/locate/fuel JFUE 9028 No. of Pages 19, Model 5G 11 March 2015 Please cite this article in press as: Andrea A et al. Bio-oil from pyrolysis of wood pellets using a microwave multimode oven and different microwave absor- bers. Fuel (2015), http://dx.doi.org/10.1016/j.fuel.2015.02.081