| Research Abstract |
The investigators have found that when a separator is added to the Centifugal Partition Chromatography (CPC), its separation mechanism becomes to be similar to that of liquid membrane transport (LMT) systems. The main research project of this fund was concentrated on the extension of this new mechanism to the problems of separation/concentration/isolation of materials, and to clarify the relation between the "separator-aided CPC" and LMT systems. The apparatus employed was Sanki Engi-neering CPC-L.L. (Model NMF).
In considering the mechanistic similarity and difference of these two techniques, a correla-tion guideline table was constructed. Direct comparison between the CPC and LMT using nitrophenols (2,4,6-trinitrophenol and p-nitro-phenol) as aqueous sample solution, and n-butanol as separator in chloroform solvent. In both technique stronger interaction with n-butanol was observed for p-nitro-phenolthan for 2,4,6-trinitrophenol. NMR spectroscopically pure fractions could readily be o
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btained by CPC from the equimolar mixture sample. At the same time, selective LMT was attained using simple and costless "carrier", i.e.. n-butanol. Hence, the CPC can be regarded as a new type of multistage LMT system. Similar relation between separator-aided CPC and LMT was observed for rare earth metal ion (RE^<3+>) samples when Di-(2-ethylhexyl)phosphoric acid (D2EHPA), a familiar extractant of these ions, was used as separator. The interaction of the RE^<2+> ions with D2EHPA in CPC and LMT was found to obey a simple equilibrium known in the corresponding extraction processes. then, by adjusting the factors which affect the equilibrium, CPC separation of righter RE^<3+> ions was attained relatively readily. Also, selective LMT of the various sets of RE^<3+> ions was realized by the use of D2EHPA. Since the separation mechanism involved in these cases is essentially acid-base type interaction. The peak broadening in CPC became significant with increase of the RE's atomic number, especially for heavier RE^<3+> ions. However, the relation between CPC and LMT was retained throughout. Further extension was attempted to opitical resolution in CPC, and fundamental pre-requisites for effective resolution by CPC wre tabulated. We are now continuing trying experimentally along this pre-requi-sites. Thus, the investigators were capable of showing high utillity of the separator-aided CPC and the applicavility of these CPC data to costless sensing procedures using liquid membranes. Less
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