Re含量对Re-Mo催化剂上丁烯自歧化反应的影响

Effect of Rhenium Contents on the Butene Self-Metathesis Reaction Performance of Rhenium-Molybdenum Catalyst

摘要:

采用等体积浸渍法制备了不同Re2O7含量的3%MoO3/γ-Al2O3催化剂，以混合丁烯（n(1-丁烯)∶n(2-丁烯)=3）为原料，在固定床反应器上考察了该催化剂在丁烯自歧化反应中的催化性能，并采用XRD、NH3-TPD、H2-TPR和N2物理吸附等方法对催化剂进行了表征。实验结果表明，在3%MoO3/γ-Al2O3催化剂中添加不同含量的铼增加了催化剂的酸量，抑制了在反应初期的“诱导期”，提高了催化剂在丁烯自歧化反应中的活性和稳定性。在80 ℃、1.0 MPa、混合丁烯WHSV=1.2 h-1的条件下，3%MoO3-1%Re2O7/Al2O3催化剂(Re2O7负载量1%，MoO3负载量3%)上丁烯自歧化反应在70h内可维持60%以上的丁烯转化率和约25%的丙烯收率。

Abstract:

3%MoO3/γ-Al2O3 catalysts with different Re2O7 contents were prepared via conventional incipient-wetness impregnation method. Mixed butene self-metathesis reactions over these catalysts were investigated in a fixed-bed reactor, where mixed butene (n(1-butene)∶n(2-butene)=3) was chosen as reactant. The catalysts were characterized by means of XRD，NH3-TPD，H2-TPR and N2-adsorption. The results indicate that addition of rhenium in 3%MoO3/γ-Al2O3 catalyst increased the acid amount, inhibited the induction period in the initial stage of the reaction, enhanced the activity and stability of catalysts in mixed butene self-metathesis reaction. Under the reaction conditions of 80 ℃, 1.0 MPa, WHSV=1.2 h-1, 1%Re2O7-3%MoO3/γ-Al2O3 catalyst gave butene conversion above 60%, propene yield remained at about 25% during 70 h on stream.