Pd-Mo-K/Al2O3催化剂的结构及合成醇性能

来源 :化学物理学报 | 被引量 : 0次 | 上传用户:ljq0310
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
采用XRD、EXAFS技术研究了不同Pd含量的Pd -Mo-K/Al2 O3 催化剂结构 ,并关联其合成低碳混合醇性能。结果表明 ,在氧化态Mo-K/Al2 O3 催化剂体系中添加Pd后 ,“K -Mo”物相晶粒变小 ,分散度提高 ,说明钯可能和钾钼物种发生了较强的相互作用。经硫化还原处理后 ,发生了氧硫交换 ,钼主要以MoS2 物种形式存在 ,其粒度随着Pd含量的增加而明显减小。尺寸的显著变化可能导致MoS2 与载体作用形式的改变 ,从而影响CO加氢催化反应的性能。在硫化态催化剂中 ,Pd的添加不仅能提高CO加氢合成醇的收率和选择性 ,而且有利于改善产物的分布。基于以上结果 ,认为“K -Mo”作用物种和Pd物种均为合成醇的催化活性组份 ,它们间的相互协同作用使催化剂性能得到显著改善 The structure of Pd-Mo-K / Al 2 O 3 catalysts with different Pd contents were studied by XRD and EXAFS techniques, and the properties of the synthesized low-carbon mixed alcohols were correlated. The results show that after the addition of Pd in ​​the oxidation state Mo-K / Al 2 O 3 catalyst system, the grain size of “K -Mo” phase becomes smaller and the dispersion degree increases, indicating that palladium may have a strong interaction with potassium and molybdenum species. Sulfide reduction treatment, the occurrence of the exchange of oxygen and sulfur, molybdenum mainly exist as MoS2 species, the particle size decreases with the increase of Pd content. Significant changes in size may lead to changes in the form of MoS2 interaction with the support, thereby affecting the catalytic performance of the CO hydrogenation reaction. In the sulfurized catalyst, the addition of Pd can not only improve the yield and selectivity of CO hydrogenation of alcohols, but also help to improve the product distribution. Based on the above results, it is considered that both the “K-Mo” acting species and the Pd species are the catalytically active components of the synthetic alcohol, and the synergistic effect among them causes the catalyst performance to be significantly improved
其他文献
A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy onychine N-oxide, was isolated from the stem and branch of Alphonsea monogyma. Its structure wa
为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7
A continuous phosphine (PH3) generation was developed and applied to the sensitive detection of phosphorus by ICP-AES. Phosphate ion in aqueous solution was con
The hexahydro-bromide salt of a new 24-membered hexaaza diphenol macrocyclic ligand, (H6BDBPH)Br6·4H2O (C26H56N6O6Br6, M, = 1028.23), crystallizes in the monoc
A new copper complex, Cu2 (pba)(bpy)2Cl2·4H2O (here pba was pro-pylenebis (oxamic acid), bpy was bipyridine), was synthesized. Crystal structure of thetitle co
用密度泛函理论 (DFT)B3LYP方法 ,在 6 311G 基组下 ,计算研究了反应Cl+F2 →ClF +F和对称反应F +ClF′→ClF +F′的机理。求得前者的过渡态为三角形 ,活化能为 15.57kJ·mo
Demethoxylation and O-demethylation of the norditerpenoid alkaloids pseudaconine and isolatatizidine were described.
用变分过渡态理论对CH3 SiH3 与氧原子O的抽提反应进行了理论研究。利用从头算计算了反应体系的构型、振动频率和能量等信息 ,分析了此反应的反应机理 ;在 2 9810 0 0K计算了
为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7
The title compound (C24H40Cl6O16V3, Mr = 950.08) was synthesizedfrom the reaction of VCl3 and NaO2CEt in CHCl3 and THF. The crystal structure hasbeen determined