Crown ether,as supramolecular compound,has highly selective complexation with alkali metal/alkaline earth metal ions.The crown ether is used in the field of coal chemical industry,to provide a new method for the study of the influence of single alkali/alkaline earth metal elements in coal on combustion,pyrolysis and gasification.The influence of different diluents,different crown ethers,extraction time,the concentration of crown ether,and extraction temperature are examined.The results show that the diluent polarity is bigger,the extraction effect of crown ether is better.Different kinds of crown ethers but with same aperture,have different complexation ability to the same alkali/alkaline earth metal ions due to different substituents in crown ether ring.Using chloroform as the diluent and dicyclohexyl 18-crown-6 as the extraction agent benefits the selection and extraction of non Na ions in the washing solution of Zhundong coal.Improving the concentration of crown ether in organic phase can effectively enhance the extraction rate,but the separation coefficient does not increase with the concentration.Increasing the temperature is not conducive to the extraction reaction as it is an exothermic reaction.%超分子化合物冠醚对碱金属/碱土金属具有特殊的选择性配合能力,将其应用于煤化工领域中,为研究煤中自带单一碱/碱土金属元素对煤燃烧、热解、气化的影响提供新方法.研究了稀释剂种类、冠醚种类、萃取时间、冠醚浓度、萃取温度对准东煤水洗液中碱/碱土金属的萃取影响.结果表明,稀释剂极性越大,冠醚萃取效果越好.相同孔径的不同种类冠醚对相同离子的配位能力有差异,这是由于冠醚环上的取代基不同造成的.氯仿作为稀释剂,二环己基18-冠醚-6作为萃取剂,对准东煤水洗液中非Na碱/碱土金属离子具有较高的选择能力和萃取能力.提高有机相萃取剂浓度可有效提升萃取率,但分离系数并不随萃取剂浓度的增大而增大.萃取反应为放热反应,升高温度不利于萃取反应进行.
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