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Fischer-Tropsch Synthesis (FTS), currently used to obtain hydrocarbons from syngas, comprises a very complex set of reactions that yield a wide variety of products. An important subset among those products are alcohols, and a novel field of study of this classical reaction involves its tuning towards the production of higher alcohols (>C2+-OH). The present work aims to adapt classic FTS catalysts – based on Fe and Co as active components – towards the production of higher alcohols. Cu has also been considered as a potential component because of its activity towards methanol synthesis. Binary catalysts were synthesized to ascertain the effect of each metal on conversion of CO and selectivity towards alcohols. A ternary catalyst was also prepared to determine any possible synergistic effects between the three metals. Catalysts containing Co and Cu had little catalytic activity, with CH4 as the major product. Catalysts containing Fe and Cu showed good conversion, with high selectivity towards heavier hydrocarbons, CO2 formation by Water-Gas Shift (WGS), and significant yield of alcohols. Catalysts loaded with Fe and Co displayed similar values of conversion, but had lower WGS activity, as well as higher selectivity towards heavier hydrocarbons and moderate formation of higher alcohols. The ternary catalyst FeCoCu showed promising results; it gave an intermediate conversion, lower WGS activity than the FeCu catalysts, and the highest selectivity towards higher alcohols. These results suggest that further tuning of metallic loading can have interesting effects on the performance of catalysts towards higher alcohol synthesis., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 1000-1004

Zeolite-based FTS catalysts are known to minimize the formation of hydrocarbons beyond the gasoline range, shifting the product distribution towards iso-paraffins, olefins and aromatics through the transformation of the primary FTS products on their acid sites. Results in literature demonstrate that the zeolite topology and the Si/Al ratio (15-140) exert a strong effect on the activity, selectivity and stability of the catalyst. Those effects have been studied for both Co- and Fe-based catalyst and various zeolites (ZSM-5, MCM-22, ITQ-2, etc.), but several aspects such as the presence of aromatics as a function of acidity and the influence of zeolite mesoporosity remain unclear. In this work Fe/ZSM-5 hybrid catalysts have been prepared, characterized and evaluated in the Fischer-Tropsch synthesis of liquid hydrocarbons. The influence of zeolite composition (Si/Al ratio = 15-240) and presence of mesoporosity have been investigated., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1008-1017

This work evaluates the influence of pyrolysis temperature (350 ºC and 450 ºC) and pressure (0.1, 1.0 and 2.0 MPa) on product yields and char properties produced from spruce biomass in a fixed bed reactor. The results showed that char yield increased with increasing pyrolysis pressure for both studied temperatures while the yields of liquids and gases decreased, in a higher extent in the range from 0.1 to 1.0 MPa. Pyrolysis temperature also affected the product distribution; char yield suffered a decline with pyrolysis temperature. Higher gas yields and larger amount of liquid fraction, were obtained as temperature rose, although this effect was less important as pyrolysis pressure increased. The porosity study revealed that pressure presented a more relevant influence for chars obtained at 450 ºC than those at 350 ºC. Additionally, surface area results suggested a possible deposition of secondary char and occlusion of the smaller pores for the chars produced at the highest temperature. A clear influence of pyrolysis conditions on char reactivity was presented; chars prepared at 450 ºC showed lower reactivity and a decreasing reactivity with pyrolysis pressure., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1274-1282

The influence of storage conditions were examined for a tar sample recovered during the co­ gasification of pine and a Polish black coal. Detailed information regarding molecular mass distribution and average mass estimates were measured by size exclusion chromatography and laser desorption mass spectrometry. These techniques revealed the presence of molecules with masses from 2000 u in these tars. UV­fluorescence spectroscopy provided information on extents of (aromatic) conjugation. Different reactions mechanisms were observed depending whether the tar was stored cold (5°C) or at room temperature., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 269-276