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采用溶胶 -凝胶法 ,制备了超细镍基负载型催化剂 ( Ni/( Ti+ Si) =1∶ 9,Ti/Si=0～ 1 ) .通过 BET、TPR、XRD、TEM、FT- IR等技术 ,考察了 Ti/Si原子比对催化剂表面及物化性能的影响 .用固定床连续流动微反装置 ,以苯加氢为模型反应考察了催化剂的加氢性能、热稳定性及抗硫毒性 .结果表明 ,用 Sol- Gel法制得的镍基负载型催化剂中 ,Ni O粒径小于 1 0 nm,均匀地分散在催化剂中 ,催化剂具有较高的热稳定性 ,反应前后 Ni O晶相与晶粒尺寸无显著变化 .在 Ni O/Ti O2 - Si O2 体系中 ,Ni O、Ti O2 参与了 Si O2 的网络结构 .Si O2 体系中适量 Ni O的加入 ,使催化剂的比表面积增加 ( Ni O/Si O2 ,SBEF=589.2 m2 /g) .Ti O2 的加入及含量的提高 ,使催化剂比表面积逐渐下降 ,中孔的体积分数逐渐增大 .孔结构的变化使 Ni原子的活性位原子数减少 ,导致催化剂在苯加氢生成环己烷反应中的活性下降 .当有合适的 Ti/Si原子比时 ,催化剂有很高的反应活性、优良的选择性、较宽的反应活性温区及优良的抗噻吩中毒性能 .
Ultrafine Ni-based supported catalysts (Ni / (Ti + Si) = 1: 9, Ti / Si = 0 ~ 1) were prepared by sol-gel method and characterized by BET, TPR, XRD, TEM, FT- Technology, the effects of atomic ratio of Ti / Si on the surface and physico-chemical properties of the catalyst were investigated.The hydrogenation performance, thermal stability and anti-sulfur toxicity of the catalyst were investigated by using fixed bed continuous flow micro-reactor with benzene hydrogenation as model reaction. The results show that the nickel-based supported catalysts prepared by Sol-Gel method have a NiO particle size less than 10 nm and are uniformly dispersed in the catalyst. The catalyst has high thermal stability. The NiO crystal phase and the crystal before and after the reaction In the Ni O / Ti O2 - Si O2 system, Ni O and Ti O2 are involved in the network structure of Si O2.The addition of Ni O in the Si O2 system increases the specific surface area of the catalyst (Ni O / Si O2, SBEF = 589.2 m2 / g) .Ti O2 addition and content increase, the specific surface area of the catalyst gradually decreased, the volume fraction of the mesopores gradually increased.The change of pore structure reduced the number of active atoms of Ni atom , Resulting in a decrease in the activity of the catalyst in the hydrogenation of benzene to cyclohexane, where appropriate Ti / Si atomic ratio, the catalyst has high reactivity, excellent selectivity, wide reactivity temperature zone and excellent anti-thiophene poisoning performance.