Alexander I. Nikiforov , Evgeny A. Chesnokov , Andrey G. Popov , Irina I. Ivanova
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引用次数: 0
Abstract
One important way to increase the production of higher-margin products from less valuable unsaturated hydrocarbons is the widely used process of catalytic metathesis. Progress in the development of more advanced metathesis catalysts is hampered by obvious gaps in scientific knowledge about this process. This work is aimed at establishing the influence of physicochemical properties of Mo-containing lower olefins metathesis catalysts and developing methods for increasing their activity through promotion. A classic support for Mo-oxide metathesis catalyst was promoted with NH4HF2, (NH4)2SiF6, H3BO3 additives. The synthesized systems were analyzed by a large set of methods. The catalytic properties of obtained systems were determined in the propylene metathesis reaction. It was shown that the proposed promotion leads to an increase in activity of the catalyst up to 8.5 times. It was shown that strong Brønsted acid sites play a decisive role in increasing activity. In addition, it has been experimentally proven that the formation of active centers occurs when the substrate interacts with Brønsted, but not Lewis acid sites on the surface of the catalyst. The discoveries obtained in this work can serve as the basis for the creation of a new generation highly active lower olefins metathesis catalysts.
期刊介绍:
The Journal of Catalysis publishes scholarly articles on both heterogeneous and homogeneous catalysis, covering a wide range of chemical transformations. These include various types of catalysis, such as those mediated by photons, plasmons, and electrons. The focus of the studies is to understand the relationship between catalytic function and the underlying chemical properties of surfaces and metal complexes.
The articles in the journal offer innovative concepts and explore the synthesis and kinetics of inorganic solids and homogeneous complexes. Furthermore, they discuss spectroscopic techniques for characterizing catalysts, investigate the interaction of probes and reacting species with catalysts, and employ theoretical methods.
The research presented in the journal should have direct relevance to the field of catalytic processes, addressing either fundamental aspects or applications of catalysis.