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Several MoS2 catalysts of different structure,prepared by in situ decomposition of ammonium heptamolyb-date(AHM)and molybdenum naphthenate(MoNaph),and by MoS2 exfoliation(TDM),were characterized by BET,X-ray diffraction(XRD),Energy Dispersive X-ray(EDX)and transmission electron microscopy(TEM).Theanalysis showed that MoS2 structure was dependant upon the preparation procedure.The activity of the catalystswas determined by measuring the hydrodeoxygenation(HDO)of phenol,4-methylphenol and 4-methoxyphenolusing a batch autoclave reactor operated at 2.8 MPa of hydrogen and temperatures ranging from 320-370°C.Bycomparing the conversion,the reactivity order of the catalysts was:AHM>TDM-D>MoNaph>thermal>MoS2powder>TDM-W.Also,the effect of reaction temperature on the HDO conversion was explained in terms of equi-librium of reversible reaction kinetics.The main products of the HDO for phenolic compounds were identified bygas chromatography/mass spectrometry(GC/MS).The results showed that the product distribution and the HDO se-lectivity were correlated with the reaction temperature.Two parallel reaction routes,direct hydrogenolysis and com-bined hydrogenation-hydrogenolysis,were confirmed by the analysis of the product distribution.High temperaturefavored hydrogenolysis over hydrogenation for HDO of phenol and 4-methoxyphenol,whereas for 4-methylphenolthe reverse was true.
Several MoS2 catalysts of different structures, prepared by in situ decomposition of ammonium heptamolyb-date (AHM) and molybdenum naphthenate (MoNaph), and by MoS2 exfoliation (TDM), were characterized by BET, X-ray diffraction The analysis showed that MoS2 structure was dependant upon the preparation procedure. The activity of the catalysts was determined by measuring the hydrodeoxygenation (HDO) of phenol, 4-methylphenol and 4-methoxyphenol using a Batch autoclave reactor operated at 2.8 MPa of hydrogen and temperatures ranging from 320-370 ° C.Bycomparing the conversion, the reactivity order of the catalysts was: AHM> TDM-D> MoNaph> thermal> MoS2powder> TDM-W.Also, the effect of reaction temperature on the HDO conversion was explained in terms of equi-librium of reversible reaction kinetics. The main products of the HDO for phenolic compounds were identified by gas chromatography / mass spectrometry (GC / MS). The results showed that the pr oduct distribution and the HDO se-lectivity were correlated with the reaction temperature. Two parallel reaction routes, direct hydrogenolysis and com-bined hydrogenation-hydrogenolysis, were confirmed by the analysis of the product distribution. High temperaturefavored hydrogenolysis over hydrogenation for HDO of phenol and 4-methoxyphenol, but for 4-methylphenol the reverse was true.