Distribution coefficients have been determined for a number of trivalent lanthanide ions on an ion exchange resin containing N-benzyliminodiacetic acid groups. At pH 2.00, μ=0.100 and 25.00°C. the relative stability trends for lanthanum through neodymium were found to be in agreement with trends previously observed with iminodiacetic acid N-methyliminodiacetic acid and N-benzyliminodiacetic acid. Beyond neodymium the distribution coefficient sequence of lanthanide-resin chelates is inverted. On the basis of the distribution coefficients, the inverted elution sequences previously reported in the literature for lanthanum and lutetium on the resin can be explained. A number of plausible explanations for the trends observed can be offered, among which are steric effects, changes in coordination number and electrostatic repulsive effects. Infrared spectral data indicate the existence of a zwitterionic lanthanide chelate species which may contribute to the latter effect.
Proceedings of the Iowa Academy of Science
©1967 Iowa Academy of Science, Inc.
Lang, C. E. and Schrobilgen, G. J.
"Stability Trends for the Lanthanides on Dowex A-1 Chelating Resin,"
Proceedings of the Iowa Academy of Science, 74(1), 54-80.
Available at: https://scholarworks.uni.edu/pias/vol74/iss1/13