| 초록 |
Dimethylether (DME) have been largely attracted as ther important alternative energy sources by blending with liquefied petroleum gas (LPG) or by replacing petroleum-based diesel. In general, bifunctional catalysts, which are composed of CuO-ZnO-Al2O3 catalyst for gydrogenation of CO and solid acid zeolite catalyst for consecutive degydration of methanol, are intensively investigated for singe-step DME sinthesis from gyngas. In the present study, the strong acidic sites on the ferrierite zeolite, which are responsible for the byproduct formetion, are selectively modified using Al2O3 with the content from 0 to 30wt% by precipitation method. The optimum compositions for a high CO conversion and a low byproduct formation such as CH4 were observed on 20wt% Al2O3-modified CuO-ZnO-Al2O3/ferrierite catalyst with a high catalytic stability. The bifunctional catalysts were further characterized to elucidate the reducibility, acidic site density and particle size variation of copper species befere and after reaction using TPR,NH3-TPD,XRD and N2O titration analyses. |
