Abstract

A multicomponent MoVSbNbCeO_x/SiO₂ oxide catalyst exhibiting high catalytic activity in the oxidative dehydrogenation of ethane to ethylene is synthesized by spray drying of a suspension of aqueous solutions of the precursors and the subsequent heat treatment in He at 350 and 600°C. At a temperature of 400–450°С in a wide ethane conversion range, the catalyst exhibits a fairly high activity and ethylene selectivity. In the presence of this catalyst, the maximum ethylene yield achieves 74% (ethane conversion of 91%, ethylene selectivity of 81.5%); this value significantly exceeds the yield in the presence of Sb-containing catalysts known from the literature. The catalyst exhibits a long-term stable on-stream behavior under reaction medium conditions without any change in the phase composition and a deterioration of the catalytic characteristics. It is shown that the catalytic properties of the synthesized catalyst are comparable to the properties of MoVTeNbO_x, which is one of the best catalysts for this process. However, the use of a Te-containing catalyst is limited, because tellurium exhibits a high toxicity and volatility during the synthesis and use of the catalysts. According to X-ray diffraction analysis, the main components of the catalyst are M1 and M2 phases stabilized on a SiO₂ surface. The HRTEM data show that a structural feature of the catalyst is the presence of an interface formed by the coherently intergrown crystals of the M1 and M2 phases.

中文翻译：

---

MoVSbNbCeO x / SiO 2多组分催化剂在乙烷氧化脱氢制乙烯中的性能

摘要

多组分MoVSbNbCeO _x / SiO ₂通过将前体水溶液悬浮液喷雾干燥并随后在350和600°C的He中进行热处理，可以合成出在乙烷氧化为乙烯的氧化脱氢反应中表现出高催化活性的氧化催化剂。在400-450°С的温度范围内，乙烷的转化率很宽，该催化剂显示出相当高的活性和乙烯选择性。在这种催化剂的存在下，最大的乙烯收率达到74％（乙烷转化率为91％，乙烯选择性为81.5％）。在文献中已知的存在含Sb的催化剂的情况下，该值大大超过了产率。该催化剂在反应介质条件下表现出长期稳定的生产过程中的行为，而相组成没有任何变化且催化特性没有下降。_x，是该过程的最佳催化剂之一。但是，含碲的催化剂的使用受到限制，因为碲在催化剂的合成和使用过程中表现出高毒性和挥发性。根据X射线衍射分析，催化剂的主要成分是稳定在SiO ₂表面上的M1和M2相。HRTEM数据表明，催化剂的结构特征是由M1和M2相的相干共生晶体形成的界面的存在。