Surveying the extraction of cesium nitrate by 1,3-alternate calix[4]-arenecrown-6 ethers in 1,2-dichloroethane

The extraction of cesium nitrate from a mixture of alkali metal nitrates by calix[4]arene crown-6 ethers in 1,2-dichloroethane diluent has been survey ed at 25 degrees C. The results reveal that smaller substituents (but large r than C-2) at the phenolic positions of the calixarene opposite the crown ether increase both the extraction efficiency and the cesium selectivity. B enzo substituents on the crown ether tend to decrease extraction strength w hile increasing cesium-to-sodium selectivity. Conversely, a cyclohexano gro up on the crown ether has a negative impact on both extraction strength and selectivity.