Journal of Analytical and Applied Pyrolysis 116 (2015) 86–95 Contents lists available at ScienceDirect Journal of Analytical and Applied Pyrolysis journa l h om epage: ww w.elsevier.com/locate/jaap Lignocellulose pyrolysis with condensable volatiles quantification by thermogravimetric analysis—Thermal desorption/gas chromatography–mass spectrometry method Frank Nsaful, Franc ¸ ois-Xavier Collard ∗ , Marion Carrier 1 , Johann F. Görgens, Johannes H. Knoetze Department of Process Engineering, Stellenbosch University, Private bag X1, Matieland 7602, Stellenbosch, South Africa a r t i c l e i n f o Article history: Received 19 May 2015 Received in revised form 26 September 2015 Accepted 4 October 2015 Available online 9 October 2015 Keywords: Pyrolysis Thermogravimetric analysis Thermal desorption Condensable volatiles GC–MS Biomass a b s t r a c t A thermogravimetric analysis technique coupled to an evolved gas analysis, namely the thermal desorp- tion/gas chromatography–mass spectrometry method (TGA–TD/GC-MS) was developed, to identify and quantify condensable volatile compounds produced during the pyrolysis of lignocellulose. Four lignocel- lulose samples of different origins (i.e., pine, bamboo, corn cob and corn stover) were pyrolysed using a TGA system. Condensable volatiles released during pyrolysis were captured onto thermal desorption tubes and subsequently identified and quantified using a TD/GC–MS method. Chemical composition of condensable volatiles was statistically correlated with the original lignocellulose composition, using Prin- cipal Component Analysis (PCA). A total of 15–19 wt% (dry weight) of biomass pyrolysis products were quantified by the method, with an average Relative Standard Deviation on the high concentration con- densable volatiles yield of 6.4%, a significant improvement to what has been reported in literature. The first two principal components accounted for 89.4% of the variance in the data and showed clear correla- tions between evolved condensable volatile compounds and compositional differences among the four biomass samples. The origin of most lignin-derived compounds could be determined, due to the limita- tion of secondary reactions under slow pyrolysis. The yield of levoglucosan and 5-hydroxymethylfurfural were consistent with the initial content of C 6 sugars in the feedstock, but also negatively correlated with the ash content. The quantification of acetic acid, the highest yielding condensable volatile product, can be used as an indicator of the number of acetyl groups in biomass. © 2015 Elsevier B.V. All rights reserved. 1. Introduction The over dependence on fossil based fuels for energy have resulted in the depletion of such resources. Coupled to this is the issue of global warming caused by the greenhouse gases (GHG) releases associated with the consumption of these fuels. To curtail these effects, research has focussed on the search for renewable and clean alternative sources of energy such as wind, solar, tidal wave, geothermal and biomass. Among these sources, biomass is the only renewable and sustainable carbon carrier [1], with the potential to ∗ Corresponding author. Fax: +27 21 808 2059. E-mail address: fcollard@sun.ac.za (F.-X. Collard). 1 Present address: Technological Development Unit (UDT), Universidad de Con- cepción, Av. Cordillera No. 2634—Parque Industrial Coronel 4191996, Casilla 4051, Concepción, Chile. be converted into fossil-fuel-replacing liquid fuels, chemicals and synthetic materials [2]. The conversion of biomass into chemicals and fuels through thermochemical processes such as pyrolysis, combustion and gasi- fication has gained much attention in recent years. Bio-oil, char and gas are the main products of pyrolysis and gasification processes [3,4]. Beside the use of pyrolysis for bio-oil and char production, the process is also a very critical first step in all thermochemical pro- cesses, including gasification and combustion [5]. For this reason, an understanding of feedstock pyrolysis properties and its impact on the conversion process is essential. This will lead to the effective design of competitive thermochemical processes for the production of fuels and chemicals from biomass, or biomass in combination with other feedstock such as coal. Many studies have been conducted on the optimization of oper- ating conditions (temperature, pressure, heating rate, residence time and particle size) for the efficient pyrolysis of lignocellulose. Others have focussed on thermal decomposition properties and http://dx.doi.org/10.1016/j.jaap.2015.10.002 0165-2370/© 2015 Elsevier B.V. All rights reserved.