Characterization of acid-base sites of nickel catalysts applied to oxidative dehydrogenation of propane

• Grant number: 16/14368-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2016
• End date: August 31, 2017
• Field of knowledge: Engineering - Chemical Engineering
• Principal Investigator: Adriana Paula Ferreira Palhares
• Grantee: Fabricio Menezes de Souza
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The oxidative dehydrogenation has been highlighted in the search for alternative and more economic ways to produce olefins like propene (important to polymers industry), due to the exothermic nature of the reaction in the presence of oxidants, especially oxygen. On the other hand, two challenges are perceived: I) the total oxidation products are thermodynamically favored, indicating that the selectivity of the catalyst is extremely important, and II) low yields are achieved due to the flammability of propane/oxygen mixture, indicating the necessity of highly stable and selective catalysts for the reaction with other oxidizers. Heterogeneous catalysts supported with metals such as iron, nickel and vandium are studied for this kind of reaction, where nickel have been showed significant propane conversion and propene selectivity according the composition, structure and charge of nickel on the catalysts. Preliminary results showed that the higher the load of nickel promoted the higher the quantity and strength of basic sites and the conversion and selectivity of the catalyst. In this sense, this work seeks to study the effect of basicity and acidity of active sites of catalysts supported on aluminum oxides, cerium and/or titanium containing different nickel loads (7.5 and 15% (m / m)), promoted or not with vanadium in the reaction mechanism of the oxidative dehydrogenation of propane, and the influence of the oxidant in the process. (AU)