Ni2P催化剂电子结构对4,6-DMDBT加氢脱硫活性和选择性的影响

采用XRD、TEM、XPS以及CO红外吸附等手段，系统研究了Fe、Co和Mo对Ni₂P电子结构的影响及其对4,6-DMDBT加氢脱硫(HDS)性能的影响。表征结果表明，3种掺杂金属可较好地调整Ni₂P位点的电子状态，影响含硫有机化合物在Ni₂P位点上的吸附能。HDS性能评价结果发现，HDS本征活性与Ni₂P位点的电子结构之间存在火山型关系，使得具有中等电子密度的Co-Ni₂P/SiO₂因适中的吸附能呈现出最佳的HDS活性。此外，Ni₂P的电子缺陷显著促进直接脱硫(DDS)选择性。与Ni₂P/SiO₂相比，Mo-Ni₂P/SiO₂中Ni₂P具有更多的电子缺陷，展现出更高的DDS选择性，而Fe-Ni₂P/SiO₂和Co-Ni₂P/SiO₂中Ni₂P因具有更高的电子密度，其DDS选择性更低。

Electronic Effects of Ni2P Catalysts on Hydrodesulfurization Activity and Selectivity of 4,6-DMDBT

The impacts of Fe, Co and Mo on the electronic structure of Ni₂P and the hydrodesulfurization (HDS) performance of 4,6-DMDBT were systematically studied by means of XRD, TEM, XPS and CO infrared adsorption. Characterization results show that the three doping metals can better adjust the electronic states of Ni₂P sites, thereby affecting the adsorption energy of sulfur organic compounds on these sites. HDS performance assessment results indicate that there is a volcano-type relationship between HDS intrinsic activity and electronic structures of Ni₂P sites, so that Co-Ni₂P/SiO₂ with a moderate electron density has the best HDS activity due to moderate absorption energy. Furthermore, the electron defects of Ni₂P can significantly facilitate the direct desulfurization (DDS) selectivity. Compared with Ni₂P/SiO₂, Ni₂P in Mo-Ni₂P/SiO₂ has more electron defects and exhibits a higher DDS selectivity, while that in Fe-Ni₂P/SiO₂ and Co-Ni₂P/SiO₂ has a lower DDS selectivity due to higher electron density.