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11 Catalytic hydropyrolysis of beech wood was conducted in a fluid bed reactor at 450°C and a total pressure 12 of 26 bar. The differences in hydrodeoxygenation activity, selectivity and the resulting product composition 13 between sulfided Mo/MgAl 2 O 4 , CoMo/MgAl 2 O 4 or NiMo/MgAl 2 O 4 catalysts have been investigated. The 14 acidity and molybdate species in the oxide catalyst precursors were characterized with ammonia 15 temperature programmed desorption (NH 3-TPD) and Raman spectroscopy. The spent sulfided catalysts 16 were also extensively characterized by scanning electron microscopy (SEM) and by scanning transmission 17 electron microscopy (STEM) coupled with energy dispersive X-ray spectroscopy (EDS). The catalytic 18 hydropyrolysis of beech wood produced four kinds of products: Liquid organic and aqueous phases, solid 19 char and gases. The solid char and aqueous phase yields were not affected by the type of catalyst. The sum 20 of condensed organics and C 4+ gas yield varied between 24.3 and 26.4 wt.% on dry, ash free basis (daf) and 21 was highest for the Mo catalyst and lowest for the NiMo catalyst. The NiMo catalyst had the highest 22 hydrogenation, cracking, and de-carbonylation activity. The oxygen content in the condensed organic phase 23 was between 9.0 and 12 wt.% on dry basis (db) and was lowest for the CoMo catalyst and highest for the

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In this work sulfided CoMo/MgAl 2 O 4 catalysts used in fluid bed catalytic hydropyrolysis for the conversion 12 of beech wood and wheat straw to liquid fuels were thoroughly characterized by Raman spectroscopy and 13 scanning (transmission) electron microscopy together with energy dispersive X-ray spectroscopy. Potassium 14 and calcium were transferred from the beech wood to the catalyst and the accumulated amounts increased 15 proportionally with the time on stream (TOS) and reached 0.67 and 0.28 wt.% after 16.2 h, respectively, 16 when beech wood was used as biomass feedstock with a feeding rate of approximately 270 g/h (4.4 kg in 17 total) beech wood to 50 g of catalyst. The concentration of coke on the spent catalyst also increased with 18 TOS and was 3.7 wt.% (carbon) after 3.5 h and 7.2 wt.% after 16.2 h, indicating that the coking rate 19 decreased with time on stream. However, SEM-EDS indicated that the carbon concentration increased 20 more on the surface than in the bulk, thereby increasing the risk of pore blocking. In addition, Raman 21 spectroscopy showed that the initially formed coke was mostly graphitic, but the coke became less ordered 22 as successive layers grew on top.