A series of supported Ni-Mo-P alloy catalysts was studied for the catalytic hydrodeoxygenation (HDO) of the cyclic five-membered ester γ-valerolactone (GVL-C₅H₈O₂) as a model compound for pyrolysis oil. Alloy formation in Ni-Mo-P was indicated by X-ray diffraction analysis and X-ray absorption near-edge spectroscopy, which showed systematic shifts with composition. The number of active sites of each metal species was estimated by factor analysis combining CO-uptake measurements and infrared (IR) spectra of adsorbed CO. It was found that the catalytic activity followed the order: Ni₂P/MCM-41 > NiMo(3:1)P/MCM-41 > NiMo(1:1)P/MCM-41 $\cong$ (Ni₂P + MoP)/MCM-41 > NiMo(1:3)P/MCM-41 > MoP/MCM-41, whereas the normalized turnover frequency based on Ni sites were similar for all the catalysts, while retaining the same order. It is concluded that adjacent surface Ni atoms are the main active sites involved in the rate-determining step (rds). The Mo-containing catalysts produced more 1-pentanol and C5 hydrocarbons than Ni₂P/MCM-41, indicating that while the exposed Ni sites governed catalytic activity, Mo sites controlled the selectivity to C5 hydrocarbons. Thus, steps following the rds were influenced by Mo sites, leading to preferences for different reaction pathway during the HDO of γ-valerolactone. The study reveals that the catalytic behavior of NiMoP catalysts can be tuned by the relative proportion of Ni and Mo sites.

研究了一系列负载型Ni-Mo-P合金催化剂，作为环状五元酯γ-戊内酯（GVL-C ₅ H ₈ O ₂）作为热解油的模型化合物，进行了催化加氢脱氧（HDO）。X射线衍射分析和X射线吸收近缘光谱法表明Ni-Mo-P中的合金形成，这表明其成分发生了系统性的变化。通过因子分析结合CO吸收测量和吸附的CO的红外（IR）光谱估计每种金属物种的活性位点数。发现催化活性遵循以下顺序：Ni ₂ P / MCM-41> NiMo（ 3：1）P / MCM-41> NiMo（1：1）P / MCM-41 $\cong$ （Ni ₂ P + MoP）/ MCM-41> NiMo（1：3）P / MCM-41> MoP / MCM-41，而所有催化剂基于Ni位置的归一化周转频率均相似，但保持不变命令。可以得出结论，相邻的表面Ni原子是速率确定步骤（rds）中涉及的主要活性位点。含Mo的催化剂比Ni ₂ P / MCM-41产生更多的1-戊醇和C5烃，表明尽管暴露的Ni位置控制催化活性，但Mo位置控制了对C5烃的选择性。因此，rds之后的步骤受Mo位点的影响，导致在对γ-戊内酯进行HDO时，对不同的反应途径有偏爱。研究表明，NiMoP催化剂的催化行为可以通过Ni和Mo位置的相对比例进行调节。