| After palladium in palladium-EDTA was selectively released by thiourea, EDTA equal to the amount of palladium was analyzed by using automatic photometric titration. In this way, the determination of palladium in palladium compounds was realized. The wavelength of determination, the amount of thiourea, the value of end-point jump ΔE, the influence of coexisting ions and the conventional titration conditions were studied systematically. The results showed that when the palladium content was in the range of 19%~60%, the relative standard deviation (RSD, n=11) was 0.11%~0.19% with a spiked recovery rate of 99.64%~100.27%, consistent with the related standard methods. Choosing thiourea instead of dimethylglyoxime as a releasing agent can solve the problem arising from the precipitation of dimethylglyoxime-Pd complex on the surface of the photometric electrode, and using automatic photometric titration can eliminate the error in judging the titration end point by the visual inspection. The automatic and rapid determination of palladium content can be realized by adopting the method developed in this study. |
