Ethylene and mixed 2-butene cis/trans isomers metathesis: Influence of lanthanum as a second metal on the WO3/SiO2 catalysts

SSCI-VIDE+ATARI+NPO:FCAInternational audienceLanthanum (0.5, 0.6, 0.75, 0.9 and 1 wt%) was added as a second metal onthe 9 wt% WO3/SiO2 catalysts by the incipient wetness impregnationmethod. The catalysts were tested in the metathesis reaction of ethyleneand 2-butene using either pure 2% trans-2-butene and the mixture of 1%cis- and 1% trans-2-butene as the reaction feed and were characterizedby X-ray diffraction (XRD), nitrogen physisorption (BET), inductivelycoupled plasma optical emission spectrometry (ICP-OES), scanningelectron microscopy, ion-exchange titration, FT-Raman, ammoniatemperature programmed desorption (NH3-TPD) and reactant temperatureprogrammed desorption (reactant-TPD). An optimum lanthanum loading at0.5 wt% could improve dispersion of tungsten active phase and adsorptionproperties of the reactants on the catalysts. The adsorption of themixed cis/trans-2-butene isomer was much improved on the La-WO3/SiO2catalysts with 0.5 wt% La