Study On 2-octanone Polycondensation And Hydrogenation To Higher Alcohol

In this paper, Al2O3 was selected for the 2-octanone polycondensation. Oxalic acid coprecipitation- wet-mixing-kneading method had been adopted for preparating four kinds of hydrogenation catalysts, including Cu-Zn, Cu-Zn-MgO, Cu-Ni and Cu-Ni-MgO, and the surface structure and properties of the catalysts were studied by means of DTA, XRD, BET and TPR techniques. The hydrogenation performance for 2-octanone and its dimers was investigated with fixed-bed micro reactor, the active component of the catalysts was selected, and the effect of the catalysts'preparation and reaction conditions on the hydrogenation was studied and the optimal conditions were determined.The results showed that main composition on the surface of Cu-Ni catalyst contained CuO and NiO when the catalysts were calcinated at different temperatures, and the NiAl2O4 and CuAl2O4 spinel structure were emerged after calcination at higher temperature. With the calcination temperature increased, the Cu-Ni and Cu-Ni-MgO catalysts'surface area decreased, but the Cu-Ni-MgO catalysts'was higher than Cu-Ni catalysts'at the same conditions. The catalyst was easier to be reduced when the calcination temperature was lower, and the reduction temperature of the Cu-Ni bimetal catalyst was lower than the single Cu or Ni catalyst because of the synergistic reaction between them, but the Cu-Ni-MgO catalyst was easier to be reduced when the MgO was added. Each of the Cu-Zn, Cu-Zn-MgO, Cu-Ni and Cu-Ni-MgO catalysts was suitable to the hydrogenation of 2-octanone, the conversion of 2-octanone and the selectivity of 2-octanol can reach up to 99.5%. It was proved that Cu-Ni catalyst possessed good catalytic performance for 2-octanone and its polycondensation products, the suitable calcination temperature and reduction temperature were 400℃, the optimal process conditions of the hydrogenation reaction were as follows: the reaction temperature was 140℃, the reaction pressure was 2.0MPa and the space velocity was 1.0h-1 , on this condition, the conversion of the 2-octanone dimers was 99.92% and the selectivity of hexadecanol was 98.42%. Compared with the Cu-Ni catalyst, the Cu-Ni-MgO catalyst showed favorable hydrogenation performance under the same preparation and reaction conditions, the catalytic activity of the two catalysts was roughly the same.