Evolution of structure and activity of char-supported iron catalysts prepared for steam reforming of bio-oil.

The aim of this study is to investigate the changes in iron phase, crystal size, surface area, and char structure/reactivity of the char-supported iron catalysts after them being used for bio-oil reforming. The catalysts were prepared under different conditions (varying in temperatures, gasification agents and iron concentrations) and then used to reform bio-oil under a fixed experimental condition at 800 °C. The results show that the catalysts prepared from the steam gasification of Fe-loaded coal were preferred in terms of catalytic performance. The X-ray diffraction analysis indicates that the iron phases in the fresh catalysts varied while the used catalysts nearly showed identical iron phase of magnetite (Fe 3 O 4 ). The crystal iron particle in the catalysts would apparently increase after reforming when the initial iron phase was carbides (γ-Fe and/or α-Fe). The char structure of the catalysts was significantly affected by the ‘volatile-char interactions’ during reforming process. And the catalysts' surface area and reactivity in air were both reduced mainly due to the coke formation. [ABSTRACT FROM AUTHOR]