Study On Copolymerization Of Sulfur Dioxide Fixed With Salen Catalys

Sulfur dioxide（SO₂）is one of the main pollutants in the atmosphere,which is mainly produced by volcanic eruptions,fossil energy burning and factory emissions.In this paper,a set of copolymer of cyclohexane oxide（CHO）and low concentration SO₂（8%,6%,4%,2%）was designed for industrial emission of SO₂.The reaction was catalyzed by Salen Cr（Ⅲ）Cl synthesized with（1R,2R）-（-）-1,2-diaminocyclohexane and Cr Cl₂.Then,the structure of the catalyst was determined by FT-IR,NMR,XPS and ICP-MS,and the successful synthesis of the catalyst was proved.Subsequently,FT-IR,1H-NMR and TG analysis were performed on the poly（cyclohexene sulfite）（PCS）synthesized by five catalysts.It was proved that the structure of sulfite was contained in the polymer,and all the polymers were completely degraded at 423℃.In the investigation of catalytic single factor,the influence of different groups on the benzene ring of salicylic aldehyde on the catalytic copolymerization reaction was explored,as well as the copolymerization effect of different catalysts under different concentration of SO₂ and the change of catalytic effect after the reduction of SO₂ concentration.After single-factor investigation,five thermodynamic models were used to analyze the thermal degradation kinetics of PCS synthesized by CHO and SO₂（8%）catalyzed by the optimal catalyst Salen Cr（Ⅲ）Cl-Ⅳat different heating rates,and a thermodynamic model suitable for Salen Cr（Ⅲ）Cl catalyst was obtained.According to the thermal degradation kinetics and experimental results,the catalytic copolymerization mechanism of Salen Cr（Ⅲ）Cl catalyst was studied,and the catalytic copolymerization mechanism suitable for the catalyst in this paper was obtained.In this paper,through the study of low concentration SO₂ copolymerization,we hope to achieve the copolymerization of industrial emission SO₂,and provide a new scheme for environmental harm and resource utilization of industrial emission SO₂.