以微晶纤维素为助剂制备Ni/SBA-15加氢脱芳催化剂

Synthesis of the Ni/SBA-15 hydrodearomatization catalyst with microcrystalline cellulose as the auxiliary template

摘要:

以微晶纤维素（MCC）为辅助模板剂，制备了SBA-15介孔分子筛，并以该材料为载体制备了Ni/SBA-15-MCC加氢脱芳催化剂。通过XRD、N2吸附-脱附、FTIR、XPS、H2-TPR和SEM等手段对催化剂进行了表征，以萘的十二烷溶液为模拟油，在微型固定床反应器上评价了其催化性能。结果表明：与未添加MCC的Ni/SBA-15催化剂相比，Ni/SBA-15-MCC催化剂的孔径增大，介孔有序度更高，Ni/SBA-15-MCC表面残留的含碳基团使NiO与载体的相互作用力减弱。这些变化有利于减小反应的扩散阻力，有利于NiO分散及还原，缓解萘和四氢萘的竞争吸附，从而提高催化剂的活性及选择性。在反应压力3 MPa，温度280 ℃，氢油体积比360，质量空速2.5 h-1的条件下，Ni/SBA-15-MCC萘转化率接近100%，十氢萘选择性为98%，与Ni/SBA-15相比，分别提高了6%和10%。

Abstract:

SBA-15 mesoporous molecular sieve was prepared with the microcrystalline cellulose (MCC) as an auxiliary template, and then Ni/SBA-15-MCC hydrodearomatization catalyst was prepared with SBA-15-MCC mesoporous sieve as a support. The catalyst was characterized with XRD, N2 adsorption-desorption, FTIR, XPS, H2-TPR and SEM. The catalytic performance of the catalyst was evaluated on a fixed bed micro-reactor, with the dodecane solution of naphthalene as the model fuel. The results show of that Ni/SBA-15-MCC had the larger pore diameter and the higher mesopore order than Ni/SBA-15 without MCC. The residual carbon group on the surface of Ni/SBA-15-MCC reduce the interaction between NiO and support. Such changes are beneficial to reduce the diffusion resistance of the reaction, NiO dispersion and reduction and ease the competitive adsorption of between naphthalene and tetrahydronaphthalene, thus the catalytic activity and selectivity were improved. Under the conditions of reaction, pressure 3 MPa, temperature 280 ℃, volume ratio of hydrogen to oil 360 and mass space velocity 2.5 h-1, the naphthalene conversion on Ni/SBA-15-MCC closed to 100%, and the decalin selectivity was 98.8%, compared with Ni/SBA-15, they were increased by 6% and 10% respectively.