Deactivation of Ni spinel derived catalyst during the oxidative steam reforming of raw bio-oil
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 ºC for the controlled deposition of pyrolytic lignin...
| Authors: | , , , , |
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| Format: | article |
| Publication Date: | 2020 |
| Country: | España |
| Institution: | Universidad del País Vasco |
| Repository: | Addi. Archivo Digital para la Docencia y la Investigación |
| OAI Identifier: | oai:addi.ehu.eus:10810/65466 |
| Online Access: | http://hdl.handle.net/10810/65466 |
| Access Level: | Open access |
| Keyword: | bio-oil hydrogen oxidative steam reforming Ni catalyst deactivation coke |
| Summary: | 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 ºC for the controlled deposition of pyrolytic lignin, and a fluidized bed reactor (700 ºC; S/C, 6; O/C, 0.34; space time, 0.15 gcatalysth·gbio-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 Ni0 sites and on the Al2O3 support (6 wt % of each coke type after 6 h on stream), and; ii) sintering of Ni0 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 |
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