功能化金属-有机框架材料构筑及其乙炔/二氧化碳分离性能研究

目前工业上用于从乙炔/二氧化碳混合物中提纯乙炔的冷剂蒸馏法能耗高、效率低。基于金属-有机框架材料（MOFs）的吸附分离手段有望为此提供全新且经济高效的支持技术。由于二者物理化学性质接近，已报道的用于乙炔/二氧化碳分离的MOFs材料几乎无法实现对乙炔的专一性识别，因而在环境条件下没有呈现超过30的选择分离系数。本项目以两种气体分子电子云分布差异为切入点，拟采用对MOFs构筑单元的预功能化设计或后功能化修饰等策略，开发并制备一系列具有特定孔道结构与表面化学性质的MOFs材料。一方面构筑新型高密度氟/氧功能化MOFs材料；另一方面拟将有机金属化学领域独特的金属-炔基体系引入到MOFs体系中，预期可解决目前MOFs材料对乙炔/二氧化碳分离难以达到高选择分离系数的难题。本项目拟借助模拟计算及原位表征等科学手段从理论上分析其内在作用机制，为改进或代替目前传统气体分离与纯化技术提供理论与实验依据。

The industrial separation of acetylene from carbon dioxide is currently accomplished by using energy-intensive distillation process. Developing energy-efficient alternatives to distillation is thus of great significance. Metal-organic frameworks (MOFs) via selectively adsorptive separation offer particular promise for acetylene/carbon dioxide separation by virtue of their devisable pore structures and functionalities. But even so, very few MOFs developed for this separation show the acetylene/carbon dioxide selectivity over 30, owing to their lack of the exclusive functional sites toward acetylene, as acetylene and carbon dioxide have very similar physicochemical properties. Our project will focus on the electron cloud distribution difference between acetylene and carbon dioxide, and plan to design and fabricate functionalized MOFs with tailor-made pore structure and functionality, including fluorine- and oxygen- functionalized MOFs. Particularly, we will introduce the unique metal-alkynyl system from the organometallic chemistry into porous MOF materials, and thus probably offering the record-high adsorptive selectivity of acetylene over carbon dioxide. Moreover, we would reveal their intrinsic separation mechanism by means of the in-situ characterization and detailed computational studies, offering the particular prospect of functionalized MOF materials for this important but challenging separation.