Development of catalysts with earth-abundant metals for selective hydrogenation of alkynes

Abstract

The use of molecular modifiers or auxiliary ligands is a well known strategy to increase the selectivity in heterogeneous catalysis. Recently, an study of the effect of nitrogen-containing ligands on the activity of gold nanoparticles (NPs), developed in our group, showed a high activity and selectivity of this catalytic system in hydrogenation of alkynes via heterolytic H2 activation by frustrated Lewis pairs. Another strategy was developed for the synthesis of heterogeneous gold catalysts based on the pyrolysis of the metal-ligand system, resulting in nanoparticles coated with carbon doped with nitrogen or phosphorus (graphene N, P-doped). This material was also active in the hydrogenation reactions, and the pure material does not present any activity. The use of Earth-abundant metals in catalysis, as well as in the selective hydrogenation of alkynes is desired, corroborating the importance of this reaction for the industry, but the use of metals such as Ni and Co is still a challenge. The objective of this project is the development of nickel and cobalt nanoparticle catalysts through the pyrolysis of ligands with nitrogen or phosphorus, aiming to control the particles size and its coating with a layer of carbon doped with heteroatoms, as well as the study of the activity, selectivity and stability of the catalysts in the selective hydrogenation of alkynes to alkenes. This project will be carried out within the scope of the Fapesp 2016/16738-7 Project.