Solid-Phase Synthesis of Nickel-Molybdenum Catalysts for Metathesis of Propylene under Mechanical Action

Abstract

The solid-phase synthesis of model aluminum-molybdenum (Al-Mo) and aluminum-nickel-molybdenum (Al-Ni-Mo) compositions constituting the catalysts for metathesis of propylene was carried out under mechanical action. The structure of model Al-Mo and Al-Ni-Mo compositions was studied using X-ray diffraction analysis, high-resolution transmission electron microscopy, infrared spectroscopy, and diffuse reflectance electron spectroscopy (UV-vis DRS). The latter method revealed the presence of isolated monomeric and oligomeric molybdate compounds in the model Al-Ni-Mo compositions. Granulated catalysts for metathesis were obtained by molding the model Al-Mo and Al-Ni-Mo compositions with aluminum hydroxide followed by calcination. Most active in the metathesis of propylene was the aluminum-molybdenum catalyst containing 2.6 wt.% Ni, 13.0 wt.% Mo and 32.7 wt.% Al. At the process temperature of 200 °С, pressure 0.1 MPa, and weight space velocity of propylene 1 h–1, the conversion of propylene on this catalyst reached 33.7 %, which makes the catalyst promising for practical application. Therewith, the weight fraction of ethylene in the reaction products was 17.5 %, and butenes – 71.3 %.