CO高选择性酯化制精细化学品的催化剂设计与合成

The reaction of CO highly selective esterification to dimethyl oxalate or dimethyl carbonate is an important way to achieve conversion and utilization of carbon resources, which not only effectively improve the level of conversion and utilization of carbon resources, but also provide high value-added fine chemicals such as dimethyl oxalate or dimethyl carbonate. Dimethyl oxalate and dimethyl carbonate are two different products of the same reaction. Thus, the effective control the reaction pathway and directed synthesis of dimethyl oxalate or dimethyl carbonate are challenging. To solve the scientific problem of the difficulty of controlling the reaction pathway, this proposal intends to combine the experimental and theoretical methods, and acquires the information of the surface and interface structures of the Pd-based heterogeneous catalysts and the intermediates via in situ and ex situ experimental characterizations, which can provide reliable models for theoretical calculation. Then the information of the transition state can be acquired and the reaction pathway can be determined accurately. Finally, the nature structures which determine the selectivities of dimethyl oxalate or dimethyl carbonate can be revealed. Then, designing and controlled synthesizing catalysts with crucial structures will be done to effectively control the reaction pathway and synthesize dimethyl oxalate or dimethyl carbonate with high selectivity. This proposal will lay the foundation for the development of a new generation of coal to ethylene glycol and coal to dimethyl carbonate catalysts technology, and provide useful guidance for the precise controlling the selectivity in the field of heterogeneous catalysis.

CO高选择性酯化制草酸二甲酯或碳酸二甲酯是实现碳资源转化利用的重要途径，不仅可以有效提升碳资源转化利用水平，而且可以提供高附加值的精细化学品如草酸二甲酯或碳酸二甲酯。草酸二甲酯和碳酸二甲酯是同一个反应的两种不同产物，如何有效控制反应路径，定向合成草酸二甲酯或碳酸二甲酯是一个具有挑战性的难题。本项目针对CO酯化反应路径控制难的科学问题，拟将实验与理论相结合，通过静态和原位动态表征实验相结合获得Pd基多相催化剂活性组分和载体的表界面结构与反应中间体信息，为建立合理的理论计算模型提供丰富的实验信息，进而通过理论计算获得反应过渡态信息，准确确定反应路径，揭示影响目标产物选择性的结构本质，设计并可控合成具有关键结构特征的催化剂，从而有效控制反应路径，定向合成目标产物草酸二甲酯或碳酸二甲酯，为开发新一代煤制乙二醇和煤制碳酸二甲酯催化剂技术奠定基础，同时为多相催化领域反应选择性的精准调控提供有益指导。

CO高选择性酯化制碳酸二甲酯(DMC)或草酸二甲酯(DMO)是实现碳资源转化利用的重要途径，对于提升我国化工产品的精细化率具有重要意义。本项目针对CO酯化反应路径控制难的科学问题，在实验结果的基础上通过理论计算揭示了产物选择性调控的催化功能基元：原子级分散的单Pd活性中心有利于通过Eley-Rideal机理生成DMC，而双Pd活性中心则有利于通过Langmuir-Hinshelwood机理生成DMO；进而通过理论计算优化、理性设计和可控合成了分子筛稳定的原子级分散Pd催化剂；通过球差校正电镜和同步辐射等表征手段，确认催化剂中原子级分散的单Pd活性中心是以PdO4的配位结构存在，与理论设计催化剂模型结构一致。该催化剂表现出很好的催化性能：CO转化率超过80%，DMC选择性接近100%，连续运行100小时性能无衰减。该项目研究成果揭示了产物选择性调控的催化功能基元，将加快CO酯化技术的工业化进程，同时为多相催化领域反应选择性的精准调控提供有益指导。