Crystal chemistry and stability of hydrated rare-earth phosphates formed at room temperature

Asumi Ochiai, Satoshi Utsunomiya

研究成果: ジャーナルへの寄稿記事

6 引用 (Scopus)

抄録

In order to understand the crystal chemical properties of hydrous rare-earth (RE) phosphates, REPO4,hyd, that form at ambient temperature, we have synthesized REPO4,hyd through the interaction of aqueous RE elements (REEs) with aqueous P at room temperature at pH < 6, where the precipitation of RE hydroxides does not occur, and performed rigorous solid characterization. The second experiment was designed identically except for using hydroxyapatite (HAP) crystals as the P source at pH constrained by the dissolved P. Hydrated RE phosphate that precipitated at pH 3 after 3 days was classified into three groups: LREPO4,hyd (La → Gd) containing each REE from La-Gd, MREPO4,hyd (Tb → Ho), and HREPO4,hyd (Er → Lu). The latter two groups included increasing fractions of an amorphous component with increasing ionic radius, which was associated with non-coordinated water. REallPO4,hyd that contains all lanthanides except Pm transformed to rhabdophane structure over 30 days of aging. In the experiments using HAP, light REEs were preferentially distributed into nano-crystals, which can potentially constrain initial RE distributions in aqueous phase. Consequently, the mineralogical properties of hydrous RE phosphates forming at ambient temperature depend on the aging, the pH of the solution, and the average ionic radii of REE, similarly to the well-crystalline RE phosphates.

元の言語英語
記事番号84
ジャーナルMinerals
7
発行部数5
DOI
出版物ステータス出版済み - 5 19 2017

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Crystal chemistry
crystal chemistry
Rare earths
Phosphates
phosphate
crystal
rare earth element
temperature
Rare earth elements
Hydroxyapatite
Temperature
Crystals
Aging of materials
hydroxide
chemical property
experiment
Chemical properties
Experiments
Crystalline materials
water

All Science Journal Classification (ASJC) codes

  • Geotechnical Engineering and Engineering Geology
  • Geology

これを引用

Crystal chemistry and stability of hydrated rare-earth phosphates formed at room temperature. / Ochiai, Asumi; Utsunomiya, Satoshi.

:: Minerals, 巻 7, 番号 5, 84, 19.05.2017.

研究成果: ジャーナルへの寄稿記事

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