Deactivation of Ni spinel derived catalyst during the oxidative steam reforming of raw bio-oil

FUEL

卷:276

Article

Arandia, Aitor^1,2  Remiro, Aingeru¹  Valle, Beatriz¹  Bilbao, Javier¹  Gayubo, Ana G.¹ 

[1] Univ Basque Country, Dept Chem Engn, UPV EHU, POB 644-48080, Bilbao, Spain

[2] Aalto Univ, Sch Chem Engn, Dept Chem & Met Engn, Espoo 02150, Finland

关键词: Bio-oil;    Hydrogen;    Oxidative steam reforming;    Ni catalyst;    Deactivation;    Coke;   

DOI  :  10.1016/j.fuel.2020.117995

来源: Elsevier

【 摘 要 】

Deactivation of a bulk catalyst derived from NiAl2O4 spinel during the oxidative steam reforming (OSR) of raw bio-oil has been studied. The experiments were performed in a continuous system with two units in series: a thermal treatment unit at 500 degrees C for the controlled deposition of pyrolytic lignin, and a fluidized bed reactor (700 degrees C; S/C, 6; O/C, 0.34; space time, 0.15 g(catalyst)h.g(bio-oil)(-1); time on stream, 1, 2, 4 and 6 h) for the OSR of the remaining oxygenates. The deactivation affects the reforming of bio-oil oxygenates according to their reactivity (from lower to higher), with the reforming of phenols being rapidly affected. The causes of deactivation are: i) coke deposition on the Ni-0 sites and on the Al2O3 support (6 wt% of each coke type after 6 h on stream), and; ii) sintering of Ni-0 crystals (with an increase in crystal size from 10.8 to 17.7 nm (measured by TEM)). The catalyst deactivation rate increases with time on stream, with the bio-oil oxygenates being the main coke precursors.

【 授权许可】

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