Density functional theory and microkinetic reactor modeling were used to investigate the hydrodeoxygenation (HDO) mechanism of glycerol on the oxygenated Mo₂C catalyst surface to understand the activity and product selectivity under practically relevant reaction conditions. Reactor simulations with multiple active site models predicted that a fully oxygenated surface with acid–base (OH,O) pairs is active for glycerol dehydration and it can selectively cleave one C–O bond to produce 3-hydroxypropanal (HPA). The acid sites are not directly involved in the C–O bond scission process; however, surface oxygen vacancy formation is promoted in the presence of acid sites. The rate-limiting C–O bond cleavage process occurs on the exposed Mo sites with a concerted β-hydrogen transfer to the nearest conjugate base (Mo–O) via an E₂ elimination mechanism. Dehydration of HPA to acrolein was observed at longer residence times. Our analysis revealed that reaction conditions, such as temperature and partial pressure of H₂, can be tuned to promote further deoxygenation of HPA and acrolein to produce propanal and propylene.

中文翻译：

---

氧改性碳化钼表面甘油加氢脱氧的活性位点识别

使用密度泛函理论和微动力学反应器建模研究甘油对含氧 Mo _{2的加氢脱氧 (HDO) 机理}C 催化剂表面，以了解实际相关反应条件下的活性和产物选择性。具有多个活性位点模型的反应器模拟预测，具有酸碱 (OH,O) 对的完全氧化表面对甘油脱水具有活性，并且它可以选择性地切割一个 C-O 键以产生 3-羟基丙醛 (HPA)。酸位不直接参与 C-O 键断裂过程；然而，在酸性位点的存在下促进了表面氧空位的形成。限速 C-O 键裂解过程发生在暴露的 Mo 位点上，同时 β-氢通过 E 2 协同转移到最近的共轭碱基 (Mo-O ₎淘汰机制。在较长的停留时间观察到 HPA 脱水成丙烯醛。我们的分析表明，可以调整反应条件，例如温度和 H ₂分压，以促进 HPA 和丙烯醛进一步脱氧以生产丙醛和丙烯。