The search for a low-cost process for the valorization of linear α-olefins combining high productivity and high selectivity is a longstanding goal for chemists. Herein, we report a soluble ruthenium olefin metathesis catalyst that performs the conversion of linear α-olefins to longer internal linear olefins with high selectivity (>99%) under neat conditions at low loadings (50 ppm) and without the need of expensive additives. This robust catalytic process allowed us to efficiently and selectively re-equilibrate the naphtha fraction (C5–C8) of a Fischer–Tropsch feed derived from non-petroleum resources to a higher-value product range (C9–C14), useful as detergent and plasticizer precursorsThis work was supported by the European Community through the seventh framework program (CP-FP 211468-2 EUMET, grant to M.R., L.F., and E.B.). M.M. thanks the CNRS, the ENSCR, Rennes Métropole, and the Région-Bretagne for their financial support. A.P. thanks the Spanish MINECO for project CTQ2014- 59832-JIN, and L.C. acknowledges funding from the King Abdullah University of Science and Technology (KAUST

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Diffuse reflectance and fluorescence emission/ excitation spectra of Ag-exchanged zeolite Y samples recorded under various pretreatment conditions and silver loadings which are known to favor the formation of silver atoms and small charged silver clusters are reported. Under low loading conditions, the spectral data are interpreted in terms of isolated silver atoms in site I by comparison with the corresponding data for silver atoms entrapped in rare gas solids. Higher silver loading favors the formation of an Ag2+ cluster which appears to be best described as a silver atom in site I interacting with a silver ion in site . Oxygen treatment at elevated temperatures (400-480 °C) of completely Ag-exchanged zeolite Y induces silver ion migration and subsequent formation of an Ag32+ cluster from the existing Ag2+ cluster by occupying the vacant site adjacent to the silver atom in site I.

Optimal exploitation of raw materials, energy saving, and environmental friendliness take nowadays a major place in the development of catalytic processes. This implies better use of raw materials, lower formation of side products and, if possible, simplified separation workup steps. In this economical and environmental context, one most successful approach to bridge the gap between homogeneous and heterogeneous catalysis is multiphasic catalysis. In its simplest version, the catalyst is dissolved in one phase (generally a polar phase) while the products and the substrates mainly remain in the second one. The catalyst can be separated by simple settling and recycled under mild conditions. Ionic liquids have recently emerged as a new class of solvents, offering large opportunities of developments for biphasic (multiphasic) catalysis. In this chapter, the Ni‐catalyzed olefin oligomerization is described. Starting from the original industrial homogeneous Dimersol process, the emergence of the biphasic Difasol system using ionic liquids as the catalyst solvent will be detailed. This biphasic process was designed and developed with the aim of reducing catalyst consumption, waste and chemicals, all in an economical feasible manner.

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