Extraction Mechanism of Lanthanide Ions into Silica-based Microparticles Studied by Single Microparticle Manipulation and Microspectroscopy

Toshiki Otaka, Tatsumi Sato, Simpei Ono, Kohei Nagoshi, Ryoji Abe, Tsuyoshi Arai, Sou Watanabe, Yuichi Sano, Masayuki Takeuchi, Kiyoharu Nakatani

Research output: Contribution to journalArticle


Single porous silica microparticles coated with a styrene-divinylbenzene polymer (SDB) impregnated with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) were injected into an aqueous 3 mol/L nitric acid solution containing trivalent lanthanide (Ln(III)), as a high-level liquid waste model. We used the microcapillary manipulation-injection technique; and the extraction rate of Ln(III), as an Ln(III)-CMPO complex, into the single microparticles was measured by luminescence microspectroscopy. The extraction rate significantly depended on the Ln(III), CMPO, or NO3- concentration, and was analyzed in terms of diffusion in the pores of the microparticles and the complex formation of Ln(III). The results indicated that the rate-determining step in Ln(III) extraction was diffusion in the pore solution of the microparticles.

Original languageEnglish
Pages (from-to)1129-1133
Number of pages5
JournalAnalytical sciences : the international journal of the Japan Society for Analytical Chemistry
Issue number10
Publication statusPublished - 2019 Oct 10



  • complex formation
  • diffusion
  • extraction
  • high-level liquid waste
  • lanthanide
  • microspectroscopy
  • Silica-based microparticle

ASJC Scopus subject areas

  • Analytical Chemistry

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