以微晶纤维素为助剂制备Ni/SBA-15加氢脱芳催化剂

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

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3MPa,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%,十氢萘选择性约为98%,与Ni/SBA-15相比,分别提高了6%和10%。

SBA-15 mesoporous molecular sieve was prepared with microcrystalline cellulose(MCC)as auxiliary template and used as support to prepare Ni/SBA-15-MCC hydrodearomatization catalyst.The catalyst was characterized by XRD,N2 adsorption-desorption,FTIR,XPS,H2-TPR and SEM techniques.Its catalytic performance was evaluated in a fixed bed micro-reactor with dodecane solution of naphthalene as simulated oil.The results showed that Ni/SBA-15-MCC had a larger pore diameter and higher mesopore order than catalyst without MCC(Ni/SBA-15).The residual carbon groups on the surface of Ni/SBA-15-MCC reduced the interaction between NiO and support.Such changes are beneficial to reduce the diffusion resistance of the reaction,Ni O dispersion and reduction,and alleviate the competitive adsorption of between naphthalene and tetrahydronaphthalene,which improves the catalytic activity and selectivity.Under the conditions of reaction pressure 3 MPa,temperature 280℃,V(hydrogen)/V(simulated oil)=360 and mass space velocity 2.5 h^-1,the conversion of naphthalene on Ni/SBA-15-MCC was close to 100%,and the selectivity of decalin was about 98%,which was an improvement of 6%and 10%compared with those of Ni/SBA-15,respectively.