Quantitative Monitoring of Erbium Ion in Alloy Samples by a Erbium Selective Sensor

This works aims at describing the construction and applications of a highly sensitive erbium(III)-selective solvent polymeric membrane sensor based on N,N'-bis(salicylidene)-2-aminobenzylamine (H2L) as the ionophore, which shows a comparatively good selectivity toward common alkali, alkaline earth, transition and heavy metal ions, and especially lanthanide ions. The range of Er3+-activity in which the sensor shows linear potential-activity behavior was found to range from 1.0 X 10(-6) to 1.0 X 10(-2) M, in which range the calibration curve of the sensor had a slope of 19.5 +/- 0.2 mV per decade and a detection limit of 5.0 x 10(-7) M at a pH range of 2.6-9.5. The response time of the sensor was found to be less than 10 seconds in the whole concentration range. The experiments confirmed that the sensor can be used for at least 10 weeks without any considerable changes in its potential response behavior. To test the analytical applicability of the designed device it was used as an indicator electrode in the potentiometric titration of Er3+ ions with EDTA and also in the determination of Er3+ content in some erbium alloy samples.