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通过浸渍法分别在Al(OH)_3和Al_2O_3中引入SiO_2,经焙烧后制备具有不同表面酸性质的SiO_2-Al_2O_3载体,以上述SiO_2-Al_2O_3及Al_2O_3为载体,采用等体积浸渍法制备Ni负载量为15%的Ni/SiO_2-Al_2O_3催化剂(分别为Ni/SA-1和Ni/SA-2)与Ni/Al_2O_3.采用N2物理吸附、Py-FTIR、NH3-TPD、XRD、H2-TPR和H2-TPD手段对催化剂进行表征,考察了表面酸性质对催化剂催化1,4-丁炔二醇高压加氢性能的影响.结果表明,SiO_2引入方式会影响Ni/Al_2O_3催化剂表面酸性质及活性组分Ni在载体表面的分散行为.在Al(OH)3中引入SiO_2时,Ni/SA-1催化剂不仅活性组分具有高分散度,而且表面具有丰富的L酸位点,L酸位点与Ni活性中心协同作用有效提高了催化剂的高压加氢性能.而在Al_2O_3中直接引入SiO_2时,SiO_2覆盖了Al_2O_3表面的L酸位点,催化剂活性组分分散度较低,表现出低的加氢活性.
The SiO 2 -Al 2 O 3 support with different surface acid properties was prepared by impregnation into Al (OH) _3 and Al_2O_3 respectively. After calcination, the SiO_2-Al_2O_3 support with different surface acid properties was prepared. The Ni loading was prepared by the same volume impregnation method using the above SiO_2-Al_2O_3 and Al_2O_3 as carriers (Ni / SA-1 and Ni / SA-2) and Ni / Al_2O_3 for 15% Ni / SiO_2-Al_2O_3 catalyst were investigated by means of N2 physical adsorption, Py-FTIR, NH3-TPD, XRD, H2-TPR and H2 -TPD was used to characterize the catalysts and the effect of surface acidity on the high pressure hydrogenation of 1,4-butanediol was investigated. The results showed that the introduction of SiO_2 could affect the surface acidity and the active component of Ni / Al_2O_3 catalyst Ni in the surface of the carrier dispersion behavior of the introduction of SiO 2 in Al (OH) 3, Ni / SA-1 catalyst not only has a high dispersion of active components, and the surface is rich in L acid sites, L acid sites and Ni The synergistic effect of the active sites can effectively improve the high pressure hydrogenation performance of the catalysts. However, when SiO 2 is directly introduced into Al 2 O 3, SiO 2 covers the L acid sites on the surface of Al 2 O 3 and low dispersibility of the active components of the catalysts, .