负载锆聚醚离子液体的制备及其催化合成碳酸丙烯酯

Preparation of polyether ionic liquid supported on zirconium and catalytic synthesis of propylene carbonate

首先合成氯化1-羧基聚醚-3-甲基咪唑离子液体([HOOC-PECH-MIM]Cl),再将其与氯化锆(ZrCl4)反应制备负载锆聚醚离子液体催化剂(Zr-[HOOC-PECH-MIM]Cl),采用红外光谱仪和核磁共振氢谱仪对其化学结构进行表征,利用热重分析仪和电镜扫描仪对其热性能和表观形貌进行测试。然后用其催化二氧化碳(CO2)合成碳酸丙烯酯。比较研究了不同温度下负载锆高分子离子液体Zr-[HOOC-PECH-MIM]Cl和负载锆小分子离子液体(Zr-[HeMIM]Cl)对催化性能的影响。结果表明,负载锆聚醚离子液体制备成功,且实现了相态转变,具有较高的热稳定性。在较低温度下其催化性能优于Zr-[HeMIM]Cl,且活性高,选择性好。当催化温度为110℃,压力为1.5MPa,负载锆聚醚离子液体Zr-[HOOC-PECH-MIM]Cl的质量分数为2.0%时,转化率和选择性分别为97.5%和92.2%。

The chloride 1-carboxyl polyether-3-methyl ionic liquid[HOOC-PECH-MIM]Cl was synthesized,and then reacted with the irconium tetrachloride（ZrCl4）to prepared polyetherl ionic liquid supported on zirconium catalyst（Zr-[HOOC-PECH-MIM]Cl）.The chemical structure of Zr-[HOOC-PECH-MIM]Cl was characterized by IR and NMR,and its thermal property and apparent morphology were determined by TG and SEM.Then the catalyst was used in catalyzing carbon dioxide（CO2）to synthesize propylene carbonate.The effects of different temperatures on the catalytic properties of Zr-[HOOC-PECH-MIM]Cl and small molecule ionic liquid（Zr-[HeMIM]Cl）were studied.The results showed that the Zr-[HOOC-PECH-MIM]Cl was prepared successfully,the phase behavior was changed,and the thermal stability was better.The catalytic performance of Zr-[HOOC-PECH-MIM]Cl was better than Zr-[HeMIM]Cl at lower temperature,and possessed high activity as well as good selectivity.When temperature 110℃,pressure 1.5 MPa and the catalyst dosage 2.0%,the conversion and selectivity were 97.5% and 92.2%,respectively.