Templating mesoporous silicates on surfactant ruthenium complexes: a direct approach to heterogeneous catalysts

Abstract

Mesoporous silicas have been obtained by the true liquid crystal templating (TLCT) method, using a surfactant Ru^II complex as the template; on calcination, ruthenium-containing particles are deposited into the pores; the materials show high catalytic selectivity for the hydrogenation of hex-1-ene.

References

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8. We thank Johnson Matthey for letting us have sight of these results.
9. The catalytic reactions were performed in a PEEK-lined high pressure reactor (Cambridge Reactor Design) equipped with a stirrer and liquid sampling valve (for withdrawing samples under pressure to evaluate kinetics). In a typical reaction the autoclave was charged with ca. 50 g of hex-1-ene and the activated catalyst (ca. 20 mg, heated in vacuum at 463 K for 4 h) was directly introduced into the reactor without exposing it to air. The reactor was then pressurised with H₂ to 20 bar and heated to 373 K. Samples were periodically withdrawn without perturbing the pressure in the reactor and analysed by GC using 1,2-dichlorobenzene as the internal standard; a typical mass-balance showed minimal sample loss.
10. Apart from n-hexane, isomerised products, namely cis-and trans-hex-2-ene and small amounts trans-hex-3-ene were obtained when Cu₄Ru₁₂, Ag₄Ru₁₂ or Pd₆Ru₆ were employed as catalysts for the hydrogenation of hex-1-ene (see ref. 4). There is no detectable thermocracking.
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12. The catalytic performance of the Ag₄Ru₁₂ and Cu₄Ru₁₂ catalysts was also evaluated under identical conditions, hence meaningful comparisons of TOF may be made.