Catalytic tar removal using TiO2/NiWO4-Ni5TiO7 films

• Published in: Applied catalysis. B, Environmental Environmental, 2019-07, Vol.249, p.155-162
• Main Authors: Xu, Jing, Holthaus, Philip, Yang, Nianjun, Jiang, Siyu, Heupel, Alwin, Schönherr, Holger, Yang, Bing, Krumm, Wolfgang, Jiang, Xin
• Format: Article
• Language: English
• Subjects: Biomass; Biomass gasification; Catalyst; Catalysts; Catalytic converters; Electrolytes; Fixed bed reactors; Fixed beds; Gasification; Metal oxide nanowires; Morphology; Multilayers; Nanotechnology; Nanowires; Naphthalene; Nickel; Oxidation; Plasma electrolytic oxidation; Steam; Tar; Tar removal; Titanium dioxide
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2019.03.006

[Display omitted] •Synthesis of TiO2-NiWO4/Ni5TiO7 film based catalysts.•Clarification of experimental conditions on the synthesis of TiO2-TiWO4/Ni5TiO7 catalysts.•High efficiency and long-term stability of TiO2-NiWO4/Ni5TiO7 catalysts towards tar removal. One-dimensional nickel catalysts are more promising than nickel powders for catalytic tar removal from biomass gasification, originating from their unique morphologies and higher specific surfaces. Herein, we demonstrate the application of a Ti supported multilayer system, namely a TiO2/NiWO4-Ni5TiO7 film, for catalytic tar removal. This film is synthesized via plasma electrolytic oxidation (PEO) combined with subsequently impregnation and annealing. The surface morphology and the size of as-synthesized Ni5TiO7 nanowires are determined mainly by used electrolytes during PEO processes. For catalytic tar removal, a fixed bed reactor is utilized and naphthalene is chosen as a model tar. This TiO2/NiWO4-Ni5TiO7 film exhibits higher efficiency than thermal cracking as well as long-term stability towards catalytic steam reformation of naphthalene. A naphthalene conversion rate of 63% is achieved at 800 °C with a short residence time of 0.34 s and a high tar load of 75 g mN−3. Such a TiO2-NiWO4/Ni5TiO7 film is thus promising for future tar removal from biomass gasification in the industry.