Direct propane dehydrogenation (PDH) is an attractive technology for propylene production. We show here that propane conversion is significantly enhanced by the addition of ZnO to Cr₂O₃. Furthermore, its activity is strongly dependent on the Zn/Cr molar ratio and one with Zn/Cr = 0.3 gives the highest propane conversion and propylene selectivity among the studied Zn_xCr catalysts (x denoting the molar ratio, 0–0.5). Characterization with X-ray diffraction, nitrogen physisorption, X-ray fluorescence spectroscopy, temperature-programmed reduction, temperature-programmed desorption, transmission electron microscopy, and X-ray photoelectron spectroscopy indicates that addition of zinc to Cr₂O₃ leads to formation of a spinel phase and reduction of the particle size, and hence forms more defect sites. The Arrhenius plots suggest that the apparent activation energy of the PDH reaction is significantly lowered over Zn_0.3Cr.

中文翻译：

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锌促进的铬催化剂上丙烷脱氢制丙烯的能力增强

丙烷直接脱氢（PDH）是丙烯生产中的一项有吸引力的技术。我们在这里表明，通过将ZnO添加到Cr ₂ O ₃可以显着提高丙烷的转化率。此外，它的活性在很大程度上取决于Zn / Cr的摩尔比，而在研究的Zn _x Cr催化剂中，Zn / Cr = 0.3的丙烷具有最高的丙烷转化率和丙烯选择性（x表示摩尔比，0-0.5）。通过X射线衍射，氮物理吸附，X射线荧光光谱，程序升温还原，程序升温解吸，透射电子显微镜和X射线光电子能谱表征表明，向Cr ₂ O ₃中添加了锌。导致形成尖晶石相并减小粒径，因此形成更多的缺陷部位。Arrhenius曲线表明，与Zn _0.3 Cr相比，PDH反应的表观活化能明显降低。