분말의 Zr(OH)4를 (NH4)2CrO4 수용액에 함침시킨 후 공기 중에 소성하여 zirconia에 담지된 산화크로 축매를 제조하였다. 제조된 촉매의 구조와 열적 성질을 XRD와 DT-TGA로 연구한 결과 산화크롬이 존재함으로 말미암아 zirconia의 무정형에서 tetragonal phase 그리고 tetragonal phase에서 monoclinic phase로 되는 상전이가 크롬함량에 비례하여 억제되었다. 산화크롬과 zirconia간의 상호작용으로 산환크롬은 zirconia 표면에 잘 분산되었으며, 그 결과로 α-Cr2O3 결정은 900℃이상의 소성온도에서만 관찰되었다.
Chromium oxide/zirconia catalysts were prepared by dry impregnation of powdered Zr(OH)4 with aqueous solution of (NH4)2CrO4 followed by calcining in air. The structures and thermal properties of prepared catalysts were investigated using XRD and DT-TGA. On the basis of the results obtained from X-ray diffraction and DTA for chromium oxide/zirconia, it was suggested that the presence of chromium oxide delayed the transitions of zirconia from amorphous to tertagonal phase and from tetragonal to monoclinic phase in proportion to the chromium oxide content. Chromium oxide was well dispersed on the surface of zirconia due to the strong interaction between chromium oxide and zirconia, and consequently α-Cr2O3 crystalline was observed only at calcination temperature above 900℃.
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