Xenotime dissolution dynamics under neutral and acidic conditions

Vol.20,No.1-2(2013)

Jiří Faimon Eva Šebestová Dominik Talla Karel Novotný

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Abstract
Dissolution dynamics of synthesized xenotime was experimentally studied in a discontinuous flow–through reactor. The dissolution rate constants derived from yttrium release were determined as (1.71 ± 0.74) × 10-17 mol/m2/s in near neutral solution (pH = 5.4) and (3.77 ± 0.91) × 10-15 mol/m2/s in strongly acidic solution (pH = 1.14). Compared to the dissolution dynamics of other minerals, xenotime (1) has better stability than, e.g., quartz or even monazite under given conditions and (2) could be potentially considered as suitable collector for fixation of the radionuclides from radioactive waste.

Keywords:
discontinuous flow–through reactor; dissolution dynamics; experiment; radioactive waste; synthetic xenotime
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