کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1569717 1514263 2006 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Solubility of crystalline and metamict zircon: A thermodynamic analysis
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی انرژی هسته ای و مهندسی
پیش نمایش صفحه اول مقاله
Solubility of crystalline and metamict zircon: A thermodynamic analysis
چکیده انگلیسی

Thermodynamic analyses are used to predict the aqueous solubility of crystalline and metamict zircon at 25 °C and 150 °C for encapsulation purposes. The effect of the metamict state on solubility is treated as being equivalent to an increase in chemical free energy due to the development of amorphism. Both crystalline and metamict zircon exhibit pH-dependent behavior with minimum solubility at pH ∼5.4 and ∼4 for temperatures of 25 °C and 150 °C, respectively. Dissolution behavior may be incongruent or congruent, depending on pH, temperature and degree of metamictization (amorphism). A conservative approach is taken to the estimation of long-term dissolution rates at pH 5.4 and 4, based on a worst case scenario, where dissolution falls under mass transport control in the liquid phase. With increasing amorphism, unleached ZrO2 residue produced during incongruent leaching conditions must function as an effective dissolution barrier to maintain long-term low dissolution rates.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Nuclear Materials - Volume 357, Issues 1–3, 15 October 2006, Pages 221–233
نویسندگان
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