Mesostructured Zn/ZSM-5 Zeolite as Catalyst for Furan Deoxygenation

摘要

The furan conversion into aromatics over zinc promoted ZSM-5 zeolites was studied in a continuous-flow fixed-bed reactor. Two series of microporous and mesoporous catalysts were prepared at different zinc loadings of 2 and 5 wt.%. It was intended to optimize the overall aromatics production and control coke accumulation over novel synthesized mesoporous ZSM-5 catalyst, in a continuous flow reactor. The catalysts were characterized using X-ray diffraction (XRD), nitrogen adsorption/desorption, ammonia temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). The zinc loaded mesoporous materials exhibit an XRD pattern that matches with the ZSM-5 XRD reference pattern. No extra peaks were observed in the XRD results indicating the high dispersion of zinc species. The initial furan conversion rate was higher over the microporous catalysts, and increased upon increasing metal loading, however contrary to the mesoporous samples, the microporous ones deactivated rapidly over 2 hours of time on-stream. The results indicated that around 40 % of carbon in the fed furan, was recovered in aromatics when the new mesostructured zeolite catalyst was used, whereas this could be further increased to 50 % by the addition of zinc in the catalyst, benzene being the major product.