Pyrolysis Two-Dimensional GC-MS of Miscanthus Biomass: Quantitative Measurement Using an Internal Standard Method

Abstract

Accurate measurement of biomass pyrolysis products can provide valuable guidance for thermal processing. However, pyrolysis generates large numbers of compounds in varying concentrations, factors that can make compound identification and quantitation difficult. In this study, Miscanthus biomass samples were analyzed using pyrolysis/two-dimensional gas chromatography/mass spectrometry (Py-GCxGC-MS), which provided a more comprehensive chromatographic separation and mass spectral compound identification. Quantitative measurement was performed for 34 calibrated pyrolysis compounds using an internal standard method. Pyrolysis efficiency was measured as a function of sample mass, pyrolysis temperature, and pyrolysis temperature ramp rate. For most of the calibrated pyrolysis products, production efficiency decreased with sample mass, increased with pyrolysis temperature, and decreased with pyrolysis temperature ramp rate. Significantly, the temperature profiles of the different pyrolysis products were variable, notably acetic acid and the vinyl and formyl derivatives of phenol and guaiacol, which were produced at lower temperatures compared to other compounds such as the syringyl derivatives and levoglucosan. Lignol ratios were compared with those generated using 1H/13C heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance spectroscopy (NMR). Lower fractions of syringyl- and guaiacyl-lignols and higher fractions of the phenol-lignols were generated by Py-GCxGC-MS compared to HSQC-NMR.

Measuring biomass fast pyrolysis kinetics: State of the art

“…S‐lignol decomposition products were very less compared to those from H and G‐lignols even at higher temperatures (550°C). Groenewold et al reported 10.37 wt.% as the highest yield of LVG, 1.44 wt.% of acetic acid, 0.19 wt.% furfural, 0.13 wt.% of 5‐HMF (Groenewold et al, ). The results of furfural (0.24 %) and 5‐HMF (0.22 %) are comparable to those of Negahdar et al, while LVG and acetic acid were reported as 5.6% and 4.6%, respectively (Negahdar et al, ).…”

“…More such experiments are needed to investigate the intrinsic kinetics of biomass fast pyrolysis. Recently, Groenewold et al (2017) have demonstrated quantitative analysis of biomass fast pyrolysis products in a Py-GCxGC-MS system with 9-(9H)-fluorenone vapors introduced as internal standard at the interface of reactor and injector of the GC. Because the variation of mono-lignol release with respect to temperature could be well captured one could conclude that the H-lignol decomposition products were most abundant at low temperatures (400 C), while G-lignol products were abundant at 450 C. S-lignol decomposition products were very less compared to those from H and G-lignols even at higher temperatures (550 C).…”

“…Because the variation of mono-lignol release with respect to temperature could be well captured one could conclude that the H-lignol decomposition products were most abundant at low temperatures (400 C), while G-lignol products were abundant at 450 C. S-lignol decomposition products were very less compared to those from H and G-lignols even at higher temperatures (550 C). Groenewold et al reported 10.37 wt.% as the highest yield of LVG, 1.44 wt.% of acetic acid, 0.19 wt.% furfural, 0.13 wt.% of 5-HMF (Groenewold et al, 2017). The results of furfural (0.24 %) and 5-HMF (0.22 %) are comparable to those of Negahdar et al, while LVG and acetic acid were reported as 5.6% and 4.6%, respectively (Negahdar et al, 2016).…”

Miscanthus x giganteus Stem versus Leaf-derived Lignins Differing in Monolignol Ratio and Linkage

“…Currently, there are approximately 17 species investigated in Europe for energy and material development including Miscanthus tinctorius, M. sinensis, M. sacchariflorus and the triploid genotype M. x giganteus, an allotriploid hybrid of the diploid M. sinensis and the tetraploid M. sacchariflorus. Miscanthus field trials have been performed in Europe over the past 25 years and their linkages differ significantly [49][50][51][52][53][54][55][56][57][58][59][60]. Figure 1 shows the most common linkages of lignin formed during biosynthesis, some of them confirmed within the last five years [55,61,62].…”

Development of two‐dimensional gas chromatography (GC×GC) coupled with Orbitrap‐technology‐based mass spectrometry: Interest in the identification of biofuel composition

“…At a high mass resolving power, the data acquisition rate and mass accuracy were not significantly impacted by changing the IT from 1 to 5 milliseconds and the value of the AGC target from 10 5 to 10 6 (Table 1). However, at the lowest mass resolving power (7500), the data acquisition rate decreased from 43 to 36 Hz, whereas the IT increased from 1 to 5 milliseconds (the AGC target was set as 10 6 ). It could be noticed that the absolute intensities and S/N remained steady while the parameters changed, demonstrating that the resolving power did not affect the sensitivity of the results.…”