Güray Yildiz

Quantitative analysis of crude and stabilized bio-oils by comprehensive two-dimensional gas-chromatography.

Bio-oils produced by fast pyrolysis of lignocellulosic biomass have proven to be a promising, clean, and renewable energy source. To better assess the potential of using bio-oils for the production of chemicals and fuels a new comprehensive characterization method is developed. The combination of the analyical power of GC×GC-FID and GC×GC-TOF-MS allows to obtain an unseen level of detail for both crude and hydrotreated bio-oils originated from pine wood biomass. The use of GC×GC proves to be essential to capture the compositional differences between crude and stabilized bio-oils. Our method uses a flame ionization detector to quantify the composition, while GC×GC-TOF-MS is used for the qualitative analysis. This method allows quantification of around 150 tentatively identified compounds, describing approximately 80% of total peak volume. The number of quantified compounds in bio-oils is increased with a factor five compared to the present state-of-the-arte. The necessity of using multiple internal standards (dibutyl ether and fluoranthene) and a cold-on column injector is also verified.

Potential of genetically engineered hybrid poplar for pyrolytic production of bio-based phenolic compounds.

Wild-type and two genetically engineered hybrid poplar lines were pyrolyzed in a micro-pyrolysis (Py-GC/MS) and a bench scale setup for fast and intermediate pyrolysis studies. Principal component analysis showed that the pyrolysis vapors obtained by micro-pyrolysis from wood of caffeic acid O-methyltransferase (COMT) and caffeoyl-CoA O-methyltransferase (CCoAOMT) down-regulated poplar trees differed significantly from the pyrolysis vapors obtained from non-transgenic control trees. Both fast micro-pyrolysis and intermediate pyrolysis of transgenic hybrid poplars showed that down-regulation of COMT can enhance the relative yield of guaiacyl lignin-derived products, while the relative yield of syringyl lignin-derived products was up to a factor 3 lower. This study indicates that lignin engineering via genetic modifications of genes involved in the phenylpropanoid and monolignol biosynthetic pathways can help to steer the pyrolytic production of guaiacyl and syringyl lignin-derived phenolic compounds such as guaiacol, 4-methylguaiacol, 4-ethylguaiacol, 4-vinylguaiacol, syringol, 4-vinylsyringol, and syringaldehyde present in the bio-oil.

CHAPTER 10:Catalytic Fast Pyrolysis Over Zeolites

This chapter provides a review of catalytic fast pyrolysis (CFP) of woody biomass over zeolites and summarizes the current status and the achievements in the research and development of the technology based on the existing literature and the commercial/industrial attempts. It addresses the technology specific processing modes and the applied process parameters. The spotlight will be on research aiming at optimal process conditions, reactor technologies, and the end product (i.e. CFP-oil) properties. Only published work including the quantitative results (which includes pyrolysis product yields, pyrolysis products’ elemental composition, etc.) obtained from meso- and macro-level laboratory scale setups, and pilot, process development units, and (semi-)commercial process units wherein woody biomass feedstock—and in some cases also the catalyst—is fed continuously, are considered in this review. The final goal is to come up with a clear picture and technical recommendations on how to realize this technique at a commercial/industrial scale.