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Inaba, Yusuke*; Tsumagari, Takayuki*; Kida, Tatsuya*; Watanabe, Wataru*; Nakajima, Yasutaka*; Fukuoka, Sachio*; Mori, Atsunori*; Matsumura, Tatsuro; Nakano, Yoshio*; Takeshita, Kenji*
Polymer Journal, 43(7), p.630 - 634, 2011/07
Times Cited Count：11 Percentile：35.53(Polymer Science)
-(tetrakis-2-pyridylmethyl)ethylenediamine (TPEN) derivatives bearing a polymerizable double bond in the substituent structure of the pyridine ring are synthesized and subjected to copolymerization with 
-isopropylacrylamide in the presence of AIBN. The obtained poly(TPEN-NIPA) gels show thermo-responsive swelling/shrinking behaviors and are employed for the extraction of cadmium(II) ion from the aqueous solution to examine the relationship of the gel characteristics and the extraction performance. The polymer gels composed of the TPEN derivative bearing C3, C4, C10 and branched C3 spacer chains are synthesized and temperature-dependent extraction behavior of cadmium ion is compared. These gels extract Cd(II) ion efficiently from the aqueous solution in the swelling state at 5
C, while little extraction is observed at 45C with shrinking. It is found that poly(TPEN-NIPA) gel of branched C3 spacer (C3b) shows the excellent thermoresponsive extraction performance.
Fukuoka, Sachio*; Kida, Tatsuya*; Nakajima, Yasutaka*; Tsumagari, Takayuki*; Watanabe, Wataru*; Inaba, Yusuke*; Mori, Atsunori*; Matsumura, Tatsuro; Nakano, Yoshio*; Takeshita, Kenji*
Tetrahedron, 66(9), p.1721 - 1727, 2010/02
Times Cited Count：18 Percentile：48.53(Chemistry, Organic)N,N,N',N'-(tetrakis-2-pyridylmethyl)ethylenediamine (TPEN) derivatives bearing the different number (1-4) of a double bond moiety on the pyridine ring are synthesized and subjected to copolymerization with N-isopropylacrylamide in the presence of AIBN. The obtained poly(TPEN-NIPA)gels show thermo-responsive swelling/shrinking behaviors and are employed for the extraction of cadmium(II) ion from the aqueous solution to examine the relationship of the gel characteristics and the extraction performance. The polymer gels composed of the TPEN derivative bearing three or four double bonds exhibit temperature-dependent change of swelling and shrinking in water. These gels extract CdII ion efficiently from the aqueous solution in the swelling state at 5C, while little extraction was observed at 45C with shrinking.
Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro; Mori, Atsunori*
Proceedings of 3rd International ATALANTE Conference (ATALANTE 2008) (CD-ROM), 8 Pages, 2008/05
A thermal-swing chromatographic process using a thermosensitive gel copolymerized with NIPA (N-isopropylacrylamide) and TPPEN (N,N,N',N'-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine) was studied for the separation of Am(III) from Eu(III). Firstly, the radiolysis of the TPPEN-NIPA gel was tested by the 
-ray irradiation and the 
nuclide adsorption. The extraction separation of Am(III) was not influenced in the radioactive environment of the proposed process. Next, the TPPEN-NIPA gel was immobilized in porous silica particles and the applicability of the gel-immobilized silica to the proposed process was tested. Am(III) was extracted selectively in the gel-immobilized silica at 5C and the separation factor of Am(III) over Eu(III) was evaluated to be 3.7. The distribution ratio of Am(III) was reduced to less than 1/20 by increasing temperature from 5C to 40C. These results indicate that the TPPEN-NIPA gel is applicable to the thermal-swing chromatographic process for the MA recovery.
Takeshita, Kenji*; Matsumura, Tatsuro; Nakano, Yoshio*
Journal of Nuclear Science and Technology, 44(12), p.1481 - 1483, 2007/12
Times Cited Count：9 Percentile：54.87(Nuclear Science & Technology)The extraction separation of trivalent minor actinides from lanthanides was examined by a thermosensitive gel, poly-NIPA (N-isopropyl acrylamide) crosslinked with a TPEN derivative, N,N,N',N'-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine (tppen). The synthesized gel showed the conformational change of polymer network with temperature, which is known as the phase transition phenomena of gel, and such conformational change was repeated stably by the thermal-swing operation between 5C and 40C. Then, Am(III) was extracted selectively in the swollen gel at 5C and released easily from the shrunken gel at 40C. The distribution ratio of Am(III) and the separation factor between Am(III) and Eu(III) were evaluated as 2000 and 18 in the swollen gel. These values are sufficient to the establishment of a practical MA recovery process. Then, both the extractability and selectivity of Am were maintained stably and the selective extraction of Am was attainable by the simple thermal-swing operation. These results suggest that the proposed gel extraction process is applicable to a MA partitioning for transmutation.
Takeshita, Kenji*; Fugate, G.*; Matsumura, Tatsuro; Nakano, Yoshio*; Mori, Atsunori*; Fukuoka, Sachio*
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM), p.120 - 125, 2007/09
Extraction separation of Am(III) and Eu(III) was examined by the thermal-swing extraction technique using a thermosensitive gel, poly-
-isopropylacrylamide (NIPA) copolymerized with a TPEN derivative, 
-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine (TPPEN). The separation of Am(III) from Eu(III) was observed in the swollen state of gel (5C) and the separation factor of Am(III) was evaluated as about 18 at pH5.2. More than 90% of Am(III) extracted into the gel was released by the volume phase transition of gel from the swollen state (5C) to the shrunken one (40C). The repetition test for the thermal swing extraction of a soft metal ion, Cd(II), which was used as a substitute of Am(III), was carried out and the extraction and release of Cd(II) were repeated three times stably under the thermal-swing operation between 5C and 40C. The radiation effect of gel on the extraction of Am and Eu was tested by the irradiation of -ray (10 kGy) and the long-term adsorption of -emitter (
Cm). The TPPEN-NIPA gel sustained no damage by these radiation tests. These results suggest that the thermal-swing extraction technique is applicable to the MA partitioning process indispensable for the establishment of P&T technology.
Takeshita, Kenji*; Ishida, Keigo; Nakano, Yoshio*; Matsumura, Tatsuro
Chemistry Letters, 36(8), p.1032 - 1033, 2007/08
Times Cited Count：22 Percentile：57.38(Chemistry, Multidisciplinary)Thermal-swing extraction of Cd(II) with a thermosensitive gel, poly-N-isopropylacrylamide (NIPA) crosslinkedwith a podand, N,N,N',N'-tetrakis(4-propenyl-oxy-2-pyridylmethyl)ethylenediamine (TPPEN), was examined. Cd(II) was extracted selectively in the gel swollen at 5C andreleased from the gel shrunken at 40C. The difference in thedistribution ratios of Cd(II) between these temperatures wasmore than 30 times.
Watanabe, Masayuki; Mirvaliev, R.*; Tachimori, Shoichi; Takeshita, Kenji*; Nakano, Yoshio*; Morikawa, Koshi*; Chikazawa, Takahiro*; Mori, Ryohei*
Solvent Extraction and Ion Exchange, 22(3), p.377 - 390, 2004/06
Times Cited Count：32 Percentile：65.75(Chemistry, Multidisciplinary)The synergistic extraction with N,N,N',N'-tetrakis(2-methylpyridyl)-ethylenediamine (TPEN) and di(2-ethylhexyl)phosphoric acid (D2EHPA) demonstrates a good selectivity for Am(III) over macro amount of Ln(III) in 1-octanol. The maximum apparent separation factor, which is defined as the ratio of the distribution ratio of Am(III) to that of Eu(III), is ca. 80 while the molar fraction between D2EHPA and TPEN is 2.0. This ratio is corresponding to the result of the spectrophotometric titration, which indicates that TPEN and D2EHPA form an aggregate in 1-octanol and two D2EHPA molecules coordinate to Eu(III) TPEN complex, [Eu(TPEN)]
. In the present study, the association of D2EHPA and TPEN is one of the most important factors for the synergistic extraction and the complexation of TPEN and D2EHPA with Eu(III).
Watanabe, Masayuki; Mirvaliev, R.*; Tachimori, Shoichi; Takeshita, Kenji*; Nakano, Yoshio*; Morikawa, Koshi*; Mori, Ryohei*
Chemistry Letters, 31(12), p.1230 - 1231, 2002/12
Times Cited Count：40 Percentile：73.3(Chemistry, Multidisciplinary)Encapsulative semi-podand type ligand, N, N, N', N' #8211; tetrakis(2-methylpyridyl)ethylenediamine (TPEN) gives good selectivity of Am(III) over trivalent lanthanide by solvent extraction. This is the first robust extraction system which can separate Am(III) from trivalent lanthanide.
Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro
Genshiryoku Bakkuendo Kenkyu, 7(1), p.11 - 16, 2001/03
no abstracts in English
Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro
Kagaku Kogaku Shimpojiumu Sirizu 74; Kinzoku No Risaikuru Oyobi Kankyo Mondai, p.89 - 95, 2000/05
no abstracts in English
Takeshita, Kenji*; Nakano, Yoshio*;
Proc. of Int. Conf. on Future Nuclear Systems (GLOBAL'99)(CD-ROM), 7 Pages, 1999/00
no abstracts in English
Matsumura, Tatsuro; Takeshita, Kenji*; Nakano, Yoshio*
no journal, ,
no abstracts in English
Takeshita, Kenji*; Ishida, Keigo; Nakano, Yoshio*; Matsumura, Tatsuro
no journal, ,
The extraction separation of trivalent minor actinides from lanthanides was examined by a thermosensitive gel, poly-NIPA crosslinked with a TPEN derivative, N,N,N',N'-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine (tppen). The synthesized gel showed the conformational change of polymer network with temperature, and such conformational change was repeated stably by the thermal-swing operation between 5C and 40C. Then, a trivalent actinide, Am(III), was extracted selectively in the swollen gel at 5C and released easily by the conformational change of polymer network to the shrunken state with the increase of temperature to 40C. The distribution ratio of Am(III) and the separation factor between Am(III) and Eu(III) were evaluated as 2000 and 20 in the swollen gel. These values are sufficient to the establishment of a practical MA recovery process.
Matsumura, Tatsuro; Takeshita, Kenji*; Nakano, Yoshio*
no journal, ,
Extraction separation of Am(III) and Eu(III) was examined by the thermal-swing extraction technique using a thermosensitive gel, poly-NIPA crosslinked with a TPEN derivative, TPPEN. Am(III) was extracted selectively in the gel swollen at 5 C and released from the gel shrunken by increasing temperature to 40 C. The separation factor of Am(III) over Eu(III), which was defined as the ratio of the distribution ratio of Am(III) to that of Eu(III), was given as about 18 at the swelling state of gel (5 C) and the distribution ratio of Am(III) was reduced to about 1/50 by the volume phase transition from the swelling state (5 C) to the shrinking one (40 C). The repetition test for the thermal swing extraction of a soft metal ion, Cd(II), which was used as a substitute of Am(III), was carried out. The extraction and release of Cd(II) was repeated three times stably by the temperature swing between 5 C and 40 C. These results suggest that Am(III) can be separated and recovered effectively from Eu(III) in nitrate aqueous solution by the thermal-swing extraction technique using TPPEN-NIPA gel.
Takeshita, Kenji*; Ogata, Tsuyoshi*; Nakano, Yoshio*; Matsumura, Tatsuro
no journal, ,
no abstracts in English
Takeshita, Kenji*; Ogata, Tsuyoshi*; Nakano, Yoshio*; Matsumura, Tatsuro; Mori, Atsunori*
no journal, ,
Extraction separation of Am(III) and Eu(III) was examined by the thermal-swing extraction technique using a thermosensitive gel, NIPA (poly-N-isopropylacrylamide) copolymerized with an encapsulating ligand, TPEN derivative called TPPEN (N,N,N',N'-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine). The separation of Am(III) from Eu(III) was observed in the swollen state of gel (5C) and the separation factor of Am(III) was evaluated as about 18 at pH5.2. More than 90% of Am(III) extracted into the gel was released by the volume phase transition of gel from the swollen state (5C) to the shrunken one (40C). The radiation effect of gel on the extraction of Am and Eu was tested by the irradiation of -ray (10 kGy) and the long-term adsorption of -emitter (Cm). The TPPEN-NIPA gel sustained no damage by these radiation tests. These results suggest that the thermal-swing extraction technique is applicable to the MA partitioning process indispensable for the establishment of P&T technology.
Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro; Mori, Atsunori*
no journal, ,
no abstracts in English
Fukuoka, Sachio*; Inaba, Yusuke*; Nakajima, Yasutaka*; Mori, Atsunori*; Takeshita, Kenji*; Matsumura, Tatsuro; Nakano, Yoshio*
no journal, ,
no abstracts in English
Ogata, Takeshi*; Takeshita, Kenji*; Oaki, Hiroshi*; Inaba, Yusuke*; Mori, Atsunori*; Matsumura, Tatsuro; Nakano, Yoshio*
no journal, ,
N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) is one of the podand-type ligands with six nitrogen-donors and recognize the slight difference in the softness between Am(III) and Eu(III). We have tried to synthesize a novel extraction chromatographic agent, which exploit such feature of TPEN. The use of the polymer gel as a support of the extractant can be expect to suppress the elution of the extractant and keep the flexibility of extractant. N,N,N',N'-tetrakis-(4-propenyloxy-2-pyridylmethyl)ethylenediamine (TPPEN) which is TPEN analog introducing polymerizable group to pyridine ring was used as a cross-linker of N-isopropylacrylamide (NIPA). Furthermore, the TPPEN-NIPA gel on highly porous silica was prepared to improve the mechanical strength of the gel. These extraction chromatographic agents have been tested for the separation of Am(III) and Eu(III). Characterization and extraction performance of the extraction chromatographic agents will be described.
Kawai, Kota*; Nakano, Yoshio*; Takeshita, Kenji*; Nagai, Takayuki; Kobayashi, Hidekazu; Amamoto, Ippei; Ayame, Yasuo
no journal, ,
no abstracts in English
