载体制备方法对Ni/ZrO_2催化剂顺酐液相加氢性能的影响

分别以水和甲醇为溶剂制备晶粒尺寸基本一致的四方相ZrO_2,通过浸渍法制备Ni质量分数10%的Ni/ZrO_2-W(水为溶剂)与Ni/ZrO_2-M(甲醇为溶剂)催化剂,考察其催化顺酐液相加氢性能。采用BET、XRD、H_2-TPR、H_2-TPD和in situ FT-IR对催化剂进行表征。结果表明,以甲醇为溶剂制备的ZrO_2比表面积明显小于以水为溶剂制备的ZrO_2,但Ni/ZrO_2-M催化剂存在强的金属-载体相互作用,其活性金属分散度以及C=O加氢活性明显高于Ni/ZrO_2-W催化剂。在反应温度210℃和氢压5 MPa条件下反应3 h,Ni/ZrO_2-M催化剂上顺酐转化率几乎100%,γ-丁内酯选择性为22.8%,Ni/ZrO_2-W催化剂上γ-丁内酯选择性仅为2.5%。

Effect of zirconia preparation methods on catalytic performance of Ni/ZrO2 #br# catalysts for liquid phase hydrogenation of maleic anhydride

Two kinds of ZrO₂ with tetragonal phase and the same crystalline size were prepared by using water and methanol as the solvents respectively.Ni/ZrO₂ catalysts with Ni mass fraction of 10% were prepared by impregnation method and applied in the liquid phase hydrogenation of maleic anhydride.The as-prepared catalysts were characterized by BET,XRD,H₂-TPR,H2-TPD and in situ FT-IR.The results showed that although the specific surface area of ZrO2 prepared by using methanol as the solvent was obviously smaller than that prepared by using water as the solvent,Ni/ZrO₂-M catalyst prepared by using methanol as the solvent had stronger metal-support interaction,higher active metal dispersion and higher CO hydrogenation activity than Ni/ZrO₂-W catalyst prepared by using water as the solvent.Under the condition of reaction temperature 210 ℃,hydrogen pressure 5 MPa and reaction time 3 h,the conversion of maleic anhydride on Ni/ZrO₂-M catalyst was 100% and the selectivity to γ-butyrolactone was 22.8%,while the selectivity to γ-butyrolactone on Ni/ZrO2-W catalyst was only 2.5% under the same reaction condition.