N,N,N',N'-Tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide as Very Effective Extraction Agent for Trivalent Europium and Americium.

Emanuel Makrlík,Vasily Babain,Mikhail Alyapyshev,Dmitriy Dar’In,Petr Vaňura,Pavel Selucký

doi:10.17344/acsi.2017.3295

Abstract

Solvent extraction of microamounts of Eu3+ and Am3+ from water into nitrobenzene by means of a mixture of hydrogen dicarbollylcobaltate (H+B-) and N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide (L) was studied. The equilibrium data were explained assuming that the species HL+, H2L2+, HL+2, ML3+2, and ML3+3 (M3+ = Eu3+, Am3+; L = N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide) are extracted into the nitrobenzene phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and discussed. From the experimental results it is evident that this effective N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide receptor for the Eu3+ and Am3+ cations could be considered as a potential extraction agent for nuclear waste treatment.

Highlights

Removal of heavy metals from wastes and soils is a very urgent environmental and technological problem
L; see Scheme 1) was investigated. In this context we must add that the solvent extraction of these trivalent cations into nitrobenzene by means of the mentioned electroneutral N,N,N’,N’-tetrabutyl1,10-phenanthroline-2,9-dicarboxamide ligand (L) is nearly negligible; the mixture of H+B– and L was employed
Phenanthroline-2,9-dicarboxamide (L)–H+B– systems can be described by the set of reactions: (1) (2) (3) (4) (5) (6) to which the following equilibrium constants correspond: (7)

Summary

Introduction

Removal of heavy metals from wastes and soils is a very urgent environmental and technological problem. G., Cs+, Sr2+, Ba2+, Eu3+, and Am3+) from aqueous solutions into a polar organic phase, both under laboratory conditions for theoretical or analytical purposes,[23,24,25,26,27] and on the technological scale for the separation of some high-activity isotopes in the reprocessing of spent nuclear fuel and acidic radioactive waste.[28,29] a process involving chlorinated cobalt dicarbollide, polyethylene glycol, and diphenyl-N,N-dibutylcarbamoylmethyl phosphine oxide, called UNEX, has been suggested for the simultaneous recovery of cesium, strontium, lanthanides, and actinides from highly acidic media into phenyltrifluoromethyl sulfone In this context we must add that the solvent extraction of these trivalent cations into nitrobenzene by means of the mentioned electroneutral N,N,N’,N’-tetrabutyl1,10-phenanthroline-2,9-dicarboxamide ligand (L) is nearly negligible; the mixture of H+B– and L was employed. We intended to find the composition of the species in the organic phase of the water–nitrobenzene extraction system and to determine the corresponding equilibrium constants

Experimental

Results and Discussion

Conclusions