Ni/γ-Al2O3催化混合长链α-烯烃加氢

Ni/γ-Al2O3 catalyzed hydrogenation of mixed long chain α-olefin

摘要:

针对混合长链α-烯烃的加氢反应特性,选用γ-Al2O3为载体,通过等体积浸渍法(DI)制备了Ni/γ-Al2O3,并利用TEM和BET等对催化剂及原料进行了表征,旨在探究催化剂孔径与混合烯烃粒径之间的关系。研究结果显示,该催化剂能够有效降低烯烃进入催化剂孔道的阻力,消除内扩散的影响。为进一步优化催化剂的性能,采用电荷增强型干法浸渍(CEDI)改进催化剂,结果发现,与DI相比,CEDI制备的催化剂催化性能提高了一倍。XRD、SEM和TEM结果表明,CEDI制备的Ni/γ-Al2O3中的Ni纳米颗粒良好地分散在载体上,颗粒尺寸约为5.0 nm,从而展现出优异的催化活性。此外,经XPS证实,Ni/γ-Al2O3中金属-载体强相互作用可以抵抗长链烯烃加氢过程中活性位点的烧结和结焦,使其具有良好的稳定性。

Abstract:

According to the hydrogenation characteristics of mixed long chain α-olefin, Ni/γ-Al2O3 was prepared using Dry Impregnation (DI) with γ-Al2O3 serving as the carrier. Both the catalyst and the raw material were characterized using TEM and BET to investigate the relationship between the pore size of the catalyst and the particle size of the mixed olefin. The results show that the catalyst can effectively reduce the resistance of olefin entering the catalyst channel and eliminate the effect of internal diffusion. In order to further optimize the performance of the catalyst, Charge Enhanced Dry Impregnation (CEDI) was employed to enhance the catalyst performance. The results showed that the catalytic performance of the catalyst prepared by CEDI was doubled compared with that of DI. Analysis through XRD, SEM, and TEM revealed that the Ni nanoparticles in Ni/γ-Al2O3 prepared by CEDI are well-dispersed on the carrier, exhibiting a particle size of approximately 5.0 nm and demonstrating excellent catalytic activity. Additionally, XPS confirmed the strong metal-carrier interaction in Ni/γ-Al2O3, which imparts resistance to sintering and coking at the active site during the hydrogenation of long-chain olefin, thereby ensuring good stability.