摘要
以NiCl_2·6H_2O为前驱体、(NH_4)_6Mo_7O_(24)·4H_2O和FeCl_3·6H_2O为助剂,通过浸渍、焙烧和NaBH_4还原制备高活性的NiMoFeB/γ-Al_2O_3催化剂。采用糠醛液相催化加氢为探针反应对其活性进行了评价。与NiMoB/γ-Al_2O_3相比,NiMoFeB/γ-Al_2O_3催化剂表现出更高的加氢活性和选择性,即使在较低温度60℃和5.0MPa条件下,加氢反应3.0h,糠醛转化率接近100%。考察Fe掺杂量和活性组分的负载顺序对催化剂活性的影响。结果表明,适宜的Fe掺杂量Mo+Ni与Fe原子比为20:1,Mo、Ni和Fe前驱体盐同时负载于γ-Al_2O_3时,催化剂活性最高。XRD研究表明,NiMoFeB/γ-Al_2O_3为无定形结构,活性组分在载体上分散均匀,具有良好的热稳定性。
MoNiFeB/γ-Al1O3 amorphous alloy catalysts were prepared by NaBH4 reduction after impreg- nating NiC12 · 6H20, （NH4）6 Mo70Ea · 4H2O and FeCl3 · 6H20 on γ-Al1O3. The activity of MoNiFeB/ γ-Al1O3 was investigated using liquid-phase hydrogenation of furfural as a probe reaction. The results showed that the hydrogenation activity and selectivity of NiMoFeB/γ-Al1O3 were higher than that of Ni- MoB/γ-Al1O3 ;after reaction for 3.0 h at 60 ℃and 5.0 MPa in methanol, furfural conversion reached nearly 100%. Effects of Fe doping amount and impregnation sequence of the activity component on cata- lytic activity were studied. The optimum atom ratio of Ni ＋ Mo to Fe was 20： 1. Impregnation sequence of the precursor salts of Ni, Mo and Fe had significant effects on catalytic activities of as-prepared catalysts. NiMoFeB/γ-Al1O3 prepared by simultaneous impregnation of Ni, Mo and Fe salts exhibited the highest catalytic activity. XRD patterns indicated that the as-prepared catalyst possessed amorphous structure with relative high dispersion of activity component and thermal stability.
出处
《工业催化》
CAS
2010年第5期14-19,共6页
Industrial Catalysis
基金
国家高技术研究发展计划项目(863计划)(2007AA05Z451)
