Please cite this article in press as: M. Bartoli, et al., Pyrolysis of -cellulose using a multimode microwave oven, J. Anal. Appl. Pyrol. (2016), http://dx.doi.org/10.1016/j.jaap.2016.05.016 ARTICLE IN PRESS G Model JAAP-3733; No. of Pages 13 Journal of Analytical and Applied Pyrolysis xxx (2016) xxx–xxx Contents lists available at ScienceDirect Journal of Analytical and Applied Pyrolysis journal h om epage: www.elsevier.com/locate/jaap Pyrolysis of -cellulose using a multimode microwave oven Mattia Bartoli a , Luca Rosi a , Alessio Giovannelli b , Piero Frediani a , Marco Frediani a,∗ a Department of Chemistry, University of Florence, Via della Lastruccia, 3-13, 50019 Sesto Fiorentino, Italy b CNR-IVALSA Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy a r t i c l e i n f o Article history: Received 2 March 2016 Received in revised form 19 May 2016 Accepted 22 May 2016 Available online xxx a b s t r a c t -Cellulose was pyrolyzed using a multimode microwave oven, different microwave absorbers and experimental set ups. The microwave absorber showed a strong influence: carbon gave a large gasifi- cation of cellulose (yield of gas up to 53.8%) while Al 2 O 3 gave a high yield of bio-char (64.1%) and a low gas production (3.0%). Bio-oil was obtained with the highest yield (37.6%) using iron as microwave absorber and a condenser between the oven and the collecting system. Dark brown bio-oils having low density and viscosity due to the presence of large amount of furanosidic compounds were collected. Bio-oils were characterized through GC–MS, FT-IR, NMR, The GC–MS analysis was employed to evalu- ate the composition of bio-oils using calculated retention factors. A high concentration of levoglucosan (133.9 mg/mL) together with acetic acid, acetic anhydride, 1-hydroxy-2-propanone, formic acid and fur- fural were obtained using graphite as microwave absorber. A mechanisms was proposed to rationalize the formation of aromatic compounds present in bio-oils. Water contents in bio-oils were affected by all parameters of the process, mainly by the microwave absorber. The use of silica has proved to be a promising way to obtain bio-oil with low water content (13%), while pyrolysis in the presence of carbon gave a large amount of water (46%). © 2016 Elsevier B.V. All rights reserved. 1. Introduction The end of fossil fuels era is becoming day by day [1] however the request of raw materials and fuels from industry is growing every year [2]. As a consequence research for renewable resource to supply oil is became very attractive [3]. Biomasses are very promising sources to satisfy the growing request of energy and raw materials [4–6] and in the same time to reduce the environ- mental impact due to their production [7]. Cellulose is particular interesting among different available biomasses because there is not interference with the availability of resource for alimentation [8]. It is the main component of woody biomasses (up to 50%) [9], and it is the most abundant polysaccharide. Cellulose is one of the main raw material for textile industry as cotton [10], it is employed for the production of polymers such as rayon [11], activated carbon [12], charcoal, and paper [13]. Furthermore cel- lulose is currently used for a lot of fine applications like filler for polymers [14,15] or drugs [16], stationary chiral phase for liquid chromatography [17] or material for building insulation [18]. An ∗ Corresponding author. E-mail address: marco.frediani@unifi.it (M. Frediani). innovative approach on the use of cellulosic materials is their use as source of chemicals through a pyrolysis process [19]. Pyrolysis of cellulose through a classic heating was reported in several papers [20,21] together with kinetic of the process and the main decompo- sition mechanism [22,23] where a high formation of levoglucosan is reported [24]. Levoglocusan is an anhydrosugar employed for the production of unhydrolysable glucose polymers [25] or in the production of bioethanol [26]. Furthermore pyrolysis of cellulose gives a great variety of very attractive furanosidic compounds such as furfural and hydroxymethylfurfural [27]. In recent year the clas- sical thermal heating is flanked with a new systems based on the use of microwave (MW) heating [28]. Microwave assisted pyrolysis (MAP) is an interesting way to perform the process in a very short time and the possibility of an easy control of the energy employed [29,30]. MAP was used to process different waste polymeric mate- rials [31–35] in different conditions to produce chemicals and fuels. Microwave are not absorbed and converted into heat by every material, so MAP was frequently performed in the presence of a MW absorber. MAP of biomass has proven to be a reliable tool to employ waste biomass as the raw material of the process [36,37] in the presence or absence of a MW absorber and its conversion into chemicals [38] with good yields of bio-oils was reported. How- http://dx.doi.org/10.1016/j.jaap.2016.05.016 0165-2370/© 2016 Elsevier B.V. All rights reserved.