Showing papers by "Mark L. Dietz published in 2000"
TL;DR: A comprehensive review of synergistic solvent extraction using crown ethers with a focus on the role of both extractants in facilitating cation-specific separations is provided in this article. But this review is limited to a single extractant.
Abstract: This paper provides a comprehensive review of synergistic solvent extraction using crown ethers with a focus on the role of both extractants in facilitating cation-specific separations. An introduction to the various equilibria affecting synergistic extraction using crown ethers is followed by a review of the work published in this field during the 1972-1999 time period. The influence of various solvent extraction parameters on the potential for cation-selective synergism is critically examined. Those synergistic extractant combinations showing cation selectivity are highlighted, as are the fundamental investigations that are the foundation of the current understanding of synergistic solvent extraction using crown ethers.
126 citations
TL;DR: The most important scientific results arising from this research during the past 10 years, a time of great change in the nuclear separations field, and to suggest possible directions for the next stage of research and development in this field are summarized in this article.
Abstract: Fundamental investigations of solvent extraction and ion exchange separations of radioactive materials have been conducted within the National Laboratory system of the U. S. Department of Energy (and its predecessor agencies) for the past 50 years. Basic research conducted at Oak Ridge and Argonne National Laboratories has produced both high quality new science and important applications in nuclear technology. The present contribution is an attempt to summarize the most important scientific results arising from this research during the past 10 years, a time of great change in the nuclear separations field, and to suggest possible directions for the next stage of research and development in this field.
57 citations
TL;DR: A homologous series of alkylenediphosphonic acids was successfully esterified with 3-(trimethylsilyl)-1-propanol to the symmetrically-substituted diesters.
16 citations
TL;DR: In this paper, small angle neutron scattering (SANS) was used to evaluate the performance of crown ether and HDOP in the presence of either the cis-syncis or cis-anti-cis stereoisomer of dicyclohexano-18-crown-6.
Abstract: Deuterated toluene solutions of di-n-octylphosphoric acid, HDOP, containing Sr+ extracted from 0.1 M LiNO3 aqueous solutions, were investigated by small angle neutron scattering (SANS). The extractions were also performed in the presence of either the cis-syn-cis or the cis-anti-cis stereoisomer of dicyclohexano-18-crown-6 (DCH18C6) in combination with HDOP in the toluene phase. The addition of the crown ether increased metal extraction into the organic phase over that observed with HDOP alone (synergistic extraction), The cis-syn-cis isomer was more effective than the cis-anti-cis isomer in enhancing Sr(II) extraction in the synergistic system. The SANS results confirmed that when the metal cation is extracted by HDOP present in large stoichiometric excess, the predominant species formed in the organic phase can be described as Sr(H(DOP)2)2 with 2 extra HDOP molecules solvating the complex. In the synergistic crown ether-HDOP system, the SANS data are consistent with solvent extraction data sugg...
13 citations
TL;DR: A comprehensive review of synergistic solvent extraction using crown ethers with a focus on the role of both extractants in facilitating cation-specific separations is provided in this article. But this review is limited to a single extractant.
Abstract: This paper provides a comprehensive review of synergistic solvent extraction using crown ethers with a focus on the role of both extractants in facilitating cation-specific separations. An introduction to the various equilibria affecting synergistic extraction using crown ethers is followed by a review of the work published in this field during the 1972-1999 time period. The influence of various solvent extraction parameters on the potential for cation-selective synergism is critically examined. Those synergistic extractant combinations showing cation selectivity are highlighted, as are the fundamental investigations that are the foundation of the current understanding of synergistic solvent extraction using crown ethers.
5 citations
TL;DR: A homologous series of alkylenediphosphonic acids was successfully esterified with 3-(trimethylsilyl)-1-propanol to the symmetrically-substituted diesters as discussed by the authors.
Abstract: A homologous series of alkylenediphosphonic acids was successfully esterified with 3-(trimethylsilyl)-1-propanol to the symmetrically-substituted diesters. The procedure, which has general applicability for incorporating silicon heteroatoms into diphosphonic acids, utilizes the esterification reagent dicyclohexyl-carbodiimide (DCC) to activate the acid. The aggregation properties of the di-[3-(trimethylsilyl)-1-propylene] alkylenediphosphonic acids were measured in toluene and 1-decanol.