Heterogeneous Catalysts In Catalyzing CO₂ Conversion To Amine Compounds

With the increment of carbon dioxide density in atmosphere,greenhouse effect becomes more and more serious.How to eliminate carbon dioxide,which is the main cause of greenhouse effect,is seen as a hot research topic.Carbon dioxide fixation receives amounts of interests as it is one of effective methods to lower CO₂ density.Nowadays,there are two main ways to eliminate CO₂:one is reduction of carbon dioxide directly,and the other is to react CO₂ with some other reagents.However,most of them are homogeneous reactions to fix CO₂.This causes problems like difficult separation and purification of target products.One way to solve this is to‘heterogenize'the homogeneous reaction.How to select the right supports plays an important role in converting homogeneous catalysts into heterogeneous one.The physical characters of supports,like high surface area,suitable pore radius,great heat resistance,are indispensable.Moreover,it is key to design a reaction according to the chemical properties of the support.In this thesis we select two types of supports for CO₂ fixation reaction:ZSM-5zeolite and KAPs.The thesis mainly discusses two reaction systems as below to explore the feasibility of heterogenization.ZSM-5 zeolite was prepared to support Cs ion to catalyze CO₂ cyclization by surface cocatalyst.Microporous organic polymers KAPs was synthesized and modified by Cu for catalyzing CO₂ formylation with amine.Characterization methods like BET,SEM et al were used to identify the physical property prepared catalysts and measure the reaction activities of the catalysts,as well as find the reaction scopes and reusable abilities of catalysts.