Preparation Of Nickel-based Catalyst With High Hydrothermal Stability And Its Performance For Hydrogenation Of Butynediol

Reppe method, which is used to synthesize 1,4-butanediol from acetylene and formaldehyde material, is the most developed processes, and has significant economic benefits. Synthesization of 1,4-butanediol from 1,4-butynediol hydrogenation is the importment part of the process. In industry, nickel-based catalyst, supported in alumina, is the most common catalyst in the second stage.In the previous work, our group has carried out the research for the catalyst which has been industrialized. We found that, in hydrothermal environment for long time, rehydration of support Al2O3 and the aggregation of Ni crystallite led to deactivation of Ni/γ-Al2O3 catalyst. In addition, SiO2 can improve the hydrothermal stability of Ni/γ-Al2O3 catalyst as a precondition to maintaining high catalytic activity. However the introduction of SiO2 decreases the mild metal-support interaction and the activity of catalyst. So improvement of dispersion and hydrothermal stability of catalyst is the key to preparation of high active Ni/γ-Al2O3 catalyst. In this paper, to solve the question, Ni-La/SiO2-Al2O3 catalyst with 3%La loading was prepared by impregnation method. The effect of introduction of La promoter was investigated such as structure of catalyst, performance of the secondary hydrogenation of 1,4-butynediol et al. And the effect of hydrothermal treatment on texure, structure, hydrogenation performance of catalyst was studied. Moreover, base on this work, the catalyst was treated in different solvents to find the effect of different environment. The main results are as follows:1.The addition of La promoter on catalytic structure, performance of the secondary hydrogenation of 1,4-butynediol were investgated. The results show that La promoter can strengthen the mild metal-support interaction, reduce Ni crystallite. Ni-La/SiO2-Al2O3 has high dispersion and the introduction of La additives makes the catalyst active component of the interaction between Ni and the support increased, Ni grain size decreases, improving the dispersion of the catalyst, and then the catalyst in the hydrogenation of butynediol the beginning of secactivity increased.2. The hydrothermal stability of Ni-La/SiO2-Al2O3 catalysts was investigated combined with a series of characterizations. The results show that the catalysts which introducted La promoter on the basis of introducting Si promoter has higher hydrothermal stability. The characterization results show that the introduction of La can increase the mild metal-support interaction and prevent the aggregation of Ni crystallite.3. The effects of different solvents and simulate different reaction conditions on the performance of Ni-La/SiO2-Al2O3 catalyst. It is found that there are difference performance of catalyst which were dealt with different solvents, so it shows that the reaction conditions can effect on the texture, structure and hydrogenation performance of catalyst. We selected GBL, H2O, BDO, THF as solvent, and the effect on the catalyst performance is GBL> H2O> BDO> THF.