The cycloaddition of CO2 with epoxide is an effective and sustainable strategy for the chemical conversion of CO2,and its product,cyclic carbonate,is applied widely in the fields of lithium-ion batteries and polymer materials.For the cycloaddition of CO2 with epoxide,it is crucial to construct catalysts with efficient epoxide adsorption activation sites since the ring-opening of the epoxide is deemed to be the key step.In this paper,TA-Zr-2,a non-homogeneous tannic acid-zirconium mesoporous material containing both Lewis acid site of zirconium metal center and hydrogen-bonding site of phenolic hydroxyl,was prepared via the coordination of tannic acid and zirconium ions.XPS and epichlorohydrin TPD-MS results showed that the zirconium metal center of TA-Zr-2 had stronger Lewis acidity and adsorption activation to epoxypropane compared to UiO-66 which was also a zirconium-based porous material.The TA-Zr-2-FD catalyst was obtained by freeze-drying treatment on basis of TA-Zr-2,and the catalytic performance was improved 1 times to TA-Zr-2 with 97.6%yield of butylene carbonate due to the larger specific surface area and suitable pore volume.In summary,a tannic acid-zirconium mesoporous material with large specific surface area was constructed by using a simple and green preparation method.The synergy of zirconium Lewis acid site and phenol hydroxyl hydrogen-bonding was beneficial to the adsorption and activation of epoxide,thus facilitating the epoxide ring-opening and enabling the catalyst to exhibit good catalytic performance for cycloaddition of CO2 with epoxide at 25℃.
关键词
CO2转化/环加成反应/环状碳酸酯/介孔材料
Key words
CO2 conversion/cycloaddition reaction/cyclic carbonate/mesoporous material
万方数据