alpha,beta-不饱和醛催化选择加氢是精细化学品合成中的重要反应。研究发现在巴豆醛选择加氢中，催化剂中金属-助剂接触界面对反应有重要影响。但目前对界面性质与巴豆醛吸附活化机制及反应行为间的相关性缺乏完整认识，使得在进一步优化巴豆醛吸附活化过程和提高反应性能方面缺乏实验和理论依据，造成现有催化剂普遍存在选择性偏低和严重失活的缺陷。为此本项目以巴豆醛气相选择加氢为模型反应，设计负载型Ir/MOx(M= Fe, Cr, Mn)催化剂，通过改变Ir和载体的颗粒尺寸，区分催化剂结构和界面差异；研究Ir-载体接触界面性质和电子传递机制对巴豆醛的吸附活化及反应行为的影响；结合反应中间体和反应历程等问题的研究，建立清晰全面的催化构效关系；认识影响反应行为的关键因素和反应机理，为进一步提高催化性能提供实验和理论支撑。本课题的实施对深入理解alpha,beta-不饱和醛选择加氢的科学本质有重要学术价值。

The catalytic selective hydrogenation of alpha,beta-unsaturated aldehyde is an important reaction in the production of various fine chemicals. Extensive investigations on selective hydrogenation of crotonaldehyde over bi-metallic catalysts revealed that the presence of metal-additive interface is crucial for catalytic performance. However, systematic investigation on the roles of such interface on the adsorption, activation and reaction behaviors of crotonaldehyde is limited, which makes it challenging to the further optimization of the adsorption/activation of crotonaldehyde and improvement of the catalytic performance. Therefore in this project, controllable syntheses of a series of supported Ir/MOX (M = Fe, Co, Mn) model catalysts and their behaviors in gas phase selective hydrogenation of crotonaldehyde as a model reaction will be investigated. By changing the particle sizes of the Ir and supports, the differences in the structural and electronic properties of these catalysts will be illustrated. The investigation will be focused on the effects of Ir-support interface on: 1, the charge transfer process; 2, the adsorption behaviors of crotonaldehyde and related the catalytic performance; 3, reaction intermediates, reaction pathways and catalyst deactivation mechanism. The findings of this research are helpful to establish a reliable structure-performance correlation, which is important for the design of highly efficient catalysts and may provide deep understanding on the nature of the selective hydrogenation of alpha,beta-unsaturated aldehydes.