Durability studies of limonite ore for catalytic decomposition of phenol as a model biomass tar in a fluidized bed

• Published in: Biomass & bioenergy 2017-12, Vol.107, p.86-92
• Main Authors: Kannari, Naokatsu, Satomi, Chika, Oyama, Yuya, Takarada, Takayuki
• Format: Article
• Language: English
• Subjects: Carbon deposition; Fluidized bed; Low-temperature gasification; O2 regeneration; Steam reforming; Tar decomposition
• ISSN: 0961-9534; 1873-2909
• DOI: 10.1016/j.biombioe.2017.09.018

The development of highly active, durable, tar decomposition catalysts is desirable for practical application of biomass gasification at low temperature. In this study, limonite ore calcinated at 900 °C was used as bed material in a fluidized bed for catalytic decomposition of phenol (biomass tar model) at 650 °C. The limonite showed catalytic activity for the decomposition of phenol to produce combustible gases (H2 and CO). A long-term durability test of phenol decomposition with O2 regeneration treatment was conducted for 25 h using the limonite catalyst. The O2 treatment repeatedly removed the deposited carbon, allowing H2 and CO to be generated constantly for 25 h. Steam reforming of phenol using the limonite catalyst was also conducted with various steam/carbon ratios (S/C = 0, 0.4, and 0.8), of which S/C = 0.4 was the best for suppressing carbon deposition and producing higher volumes of H2 and CO gases. Continuous steam reforming for 24 h could be achieved using a limonite catalyst with S/C = 0.4, while maintaining the production of H2 and CO gases, even though carbon deposition occurred steadily. These results indicated that limonite ore is a promising bed material for use in internally circulating fluidized-bed systems for long-term catalytic decomposition of biomass tar. [Display omitted] •This system permitted long-term gasification of biomass at low temperature.•Periodic burning in oxygen restored the function of the metal catalyst.•Steam reforming at a controlled steam-to-carbon ratio yielded better results.