Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Sasaki, Yuji; Nakase, Masahiko*
Petorotekku, 43(11), p.782 - 787, 2020/11
As analog compounds of DGA (diglycolamide), MIDOA(methylimino-diacetamide) and TDGA(thia-diglycolammide) are used for the extractants of platinum group metals. These extractants can be extracted noble metals and oxyanions, which followed by HSAB theory. The high concentration of these metals can be also extracted by these compounds. The research of metal-complex structures gives the information on the ability and role for complex-formation, which will be useful for the development of novel extractants.
Sasaki, Yuji; Saeki, Morihisa*; Yoshizuka, Kazuharu*
Solvent Extraction Research and Development, Japan, 26(1), p.21 - 34, 2019/06
Times Cited Count：6 Percentile：26.16(Chemistry, Multidisciplinary)Three tridentate extractants and three masking reagents including O, N, and S donors have been developed and their properties are compared and discussed. The extractants are termed as tetraoctyl-diglycolamide (TODGA), methylimino-dioctylacetamide (MIDOA) and tetraoctyl-thiodiglycolamide (TDGA(C8)) and masking agents have the same central frame but with short alkyl chain. The results of the present study indicate that TODGA can extract mainly hard acid metals belonging groups 2-4,13-15 in periodic table, MIDOA can extract soft acid metals and oxyanions (groups 5-10, 16), and TDGA can extract soft acid metals (groups 10-11). Some spectrophotometric studies (UV, IR, and NMR) indicate the stoichiometry and effect of donor atoms for metal-complexation. The Hf values, the heat generation during complex formation, obtained by chemical calculation by DFT theory show the reverse-correlation with their extraction ability.
Sasaki, Yuji; Morita, Keisuke; Saeki, Morihisa*; Hisamatsu, Shugo*; Yoshizuka, Kazuharu*
Proceedings of 21st International Solvent Extraction Conference (ISEC 2017) (Internet), p.131 - 134, 2017/11
Three tridentate extractants including soft and hard donor has been developed and examined. The extractants are termed as 
-tetraoctyl-diglycolamide (TODGA), methylimino-
-dioctylacetamide (MIDOA) and -tetraoctyl-thiodiglycolamide (TDGA). The results of the present study show that TODGA can extract completely lanthanides and actinides, MIDOA can extract palladium, technetium, and rhenium, and TDGA can extract palladium, silver, and gold. We can compare the distribution ratios of these metals by TODGA, MIDOA, and TDGA. These results can be supported by some spectrometric studies, i.e., IR, NMR and UV, and calculations of metal complexes.
Sasaki, Yuji; Morita, Keisuke; Saeki, Morihisa*; Hisamatsu, Shugo; Yoshizuka, Kazuharu*
Hydrometallurgy, 169, p.576 - 584, 2017/05
Times Cited Count：14 Percentile：55.94(Metallurgy & Metallurgical Engineering)The novel tridentate extractant including soft donor has developed and examined. The extractant, tetraoctyl-thiodiglycolamide (TDGA), is analogous structure to tetraoctyl-diglycolamide (TODGA) and methylimino-dioctylacetamide (MIDOA), but with sulfur donor instead of ether oxygen or nitrogen atoms of TODGA or MIDOA. From the present work, TDGA can extract silver, palladium, gold, and mercury from acidic solutions to n-dodecane. In addition to these results, the distribution ratios of hard and soft acid metals by using TDGA, TODGA, and MIDOA are compared, where the metal-complexations with each donor atom are investigated. 1H-NMR and IR studies for the metal-TDGA complexes indicate the role on donor atoms, S and N, of TDGA.
Sasaki, Yuji
no journal, ,
Since initially reported TODGA extractant at 2001, I have developed four analogous extractants, which have O, S, and N donor at ether position. The distribution ratios of over 70 metals using these extractants were obtained in order to know the all-inclusive extractability. Concerning with this, I developed water-soluble reagents with the same central frame but with short alkyl chains and examined their masking effects.
