| In today's energy market, there is great demand for fuel alternatives and energy independence. This has driven the path of research towards the production synthetic fuels or other alternatives, such as ethanol. Both of these products can be achieved through heterogeneous catalysis! The mechanism follows a typical CO hydrogenation reaction and is commonly referred to as Fischer-Tropsch synthesis with recognition to its discoverers. With a strong dependence on the catalytic metal applied, the reaction can produce hydrocarbon chains, (2n+1)H2 → CnH 2n+2 + nH2O, or it can produce alcohols, nCO + 2nH2 → C nH2n+2OH + (n-1)H 2O. The desired catalyst formulation typically consists of an active catalytic metal supported on a high surface area oxide with the small addition of a promoter element to increase the catalytic metal's activity and selectivity towards desired products.;The aim of this work is to investigate the rational preparation of promoted metal catalysts for these CO hydrogenation reactions, where it is agreed that a key design objective for these catalysts is to increase the promoter-metal interaction. Most industrial techniques for promoter addition typically lead to a randomly dispersed promoter element over the catalyst support. We focus on using simple techniques and common elemental precursors to maximize the interaction between the promoter and catalytic metal. This is achieved by applying the Strong Electrostatic Adsorption method. Special attention to the surface charging parameters of mixed oxide supports as a function of solution pH can create a driving force to selectively absorb a precursor complex onto a single phase of the binary mixture. This will lead to a strategically designed catalyst that should maintain intimate promoter-metal interactions through reduction/activation treatments. This work applies this procedure for the development of Mn-promoted Co/TiO2 (for long-chained hydrocarbon production) and Rh/SiO2 (for ethanol production) catalysts. |
PDF Full Text Request