Paper-structured catalyst containing CeO2–Ni flowers for dry reforming of methane.

In this paper, ceria flowers containing nano-sized catalyst Ni particles were prepared on alumina-silica fiber network for production of hydrogen from biogas. The CeO 2 flowers were prepared using hydrothermal method and then NiO was loaded on the CeO 2 flowers by impregnation method. The Paper-structured catalysts (PSCs) were prepared from alumina-silica fibers and the CeO 2 –NiO flowers using conventional paper making method. The loaded NiO particles were uniformly dispersed on the CeO 2 flowers with the use of polyvinylpyrrolidone as a dispersion enhancer, which was observed by FE-SEM and EDX analysis. The NiO particles were then reduced into Ni by using H 2. The PSCs containing CeO 2 –Ni flowers with various Ni contents (2.1, 3.4, and 4.6%) were used for dry reforming of CH 4. It was found that 3.4% amount of Ni on the PSC was suitable for reforming reaction, and the higher amount of Ni (4.6%) did not increase the CH 4 conversion. The PSC with the CeO 2 flowers had porous structure and large surface area leading to the better dispersion of the Ni particles with smaller size. This helped increase in catalytic performance, prevention of agglomerated particle catalysts at high temperature and coke forming after a long time operation. The CH 4 conversion of the PSCs containing CeO 2 –NiO flowers in the dry reforming of CH 4 was much higher (nearly 90%) with a smaller Ni content in comparison with the PSC without the CeO 2 flowers (with higher Ni content of 8.6%). Moreover, the PSCs with the flowers exhibited an excellent catalytic stability with the degradation of CH 4 conversion of only 3.1% after 50 h of reforming. In addition, the high oxygen storage capacity and oxygen mobility of CeO 2 resulted in a partial removal of coke forming on the catalyst particles during reforming. This indicated that the catalytic activity of the Ni particles dispersed on the CeO 2 flowers for dry reforming of CH 4 was superior to that of various Ni-based catalyst systems which had much higher Ni contents. Therefore, it is possible to use the PSCs containing CeO 2 –Ni flowers to generate hydrogen for use as fuels from dry reforming of CH 4. Image 1 • 5 μm spherical CeO2 flowers had open porous structure and high surface area. • NiO particle catalysts were uniformly dispersed on the CeO2 flowers. • Paper-structured catalysts (PSC) with the dispersed flowers had a great porosity. • PSCs with small Ni content exhibited excellent catalytic activity in CH4 reforming. • PSCs exhibited degradation of CH4 conversion of only 3.1% after 50 h of reforming. [ABSTRACT FROM AUTHOR]