Study of bimetallic NiFe catalysts for methyl laurate hydrogenation

The physicochemical properties of the prepared bimetallic NiFe/γ-Al₂O₃ catalysts can be affected by reduction temperature, which can change the hydrogenation activity and product selectivity for methyl laurate catalytic hydrogenation. The metal Ni active sites mainly promote the decarbonylation/decarboxylation (DCO/DCO₂) reaction, and the addition of Fe can promote the hydrodeoxygenation (HDO) reaction of methyl laurate to produce C₁₂ alkanes. The results of H₂-TPR, XRD, H₂-TPD and BET indicate that high reduction temperature is beneficial to the formation of metal or alloy active centers. The hydrogenation activity of bimetallic catalysts depends on the content of metal Ni, Fe and NiFe alloy. The ability of NiFe bimetallic catalyst to adsorb and activate H₂ is obviously affected by reduction temperature. In the studied temperature range, Ni active centers have excellent hydrogenation and cracking performances, and the introduction of Fe species can effectively inhibit the cracking performance. The sequence of catalytic hydrogenation activity for these bimetallic catalysts is:NF420 > NF360 > NF450 > NF300. When the reduction temperature is 420℃, the prepared NF420 catalyst owns the best catalytic hydrogenation performances. The conversion of methyl laurate and the selectivity of alkanes are 93.3% and 90.0% at the reaction temperature of 380℃, respectively.