Selective Hydrogenation Of Methyl Stearate With Ni/MgO Catalyst

In this thesis, Ni/MgO catalyst was prepared with precipitation-deposition method and employed for the selective hydrogenation of methyl stearate to octadecanol. The catalyst was characterized with BET, XRD, NH3-TPD etc. The physical properties of catalyst were measured, including pore volume, pore size and specific surface area.Firstly, the reaction conditions were investigated for the preparation of Ni/MgO catalysts. The influence factors included the modified metal species and adding proportion, the precipitant species, precipitation temperature, the metal loading amounts, the reduction conditions and so on. The optimized reaction conditions were:the precipitation temperature was 50 ?, the precipitation time was 20 h, precipitating agent was ammonium carbonate, the drying temperature was 60 ?, the drying time was 24 h, the reduction temperature was 500 ? with H2 as reducing agent, the reduction time was 4 h. In addition, the effects of solvent, reaction time and other factors was studied for the catalytic hydrogenation of methyl stearate., Under the optimized reaction conditions:the raw material concentration 0.17 mol/L,8 MPa hydrogen pressure and 200 ?, the conversion of methyl stearate was 31.7% and the selectivity of octadecanol was 69.6% using tetrahydrofuran as solvent. Furthermore, the selective hydrogenation for the homologous series of methyl stearate, such as lauric acid methyl ester, nutmeg acid methyl ester and palmitic acid methyl ester were investigated.