کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
675999 | 887745 | 2007 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Kinetics and thermodynamics of the attack of fluorapatite by a mixture of sulfuric and phosphoric acids at 55 °C
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A calorimetric study of kinetics and thermodynamics of the attack of a synthetic fluorapatite by a mixture of sulfuric and phosphoric acids is undertaken at 55 °C. The global enthalpy of the attack equals â409.3 kJ/mol. The recorded thermograms show two peaks leading to calcium sulfate hemihydrate and dihydrate, respectively. The deconvoluted curves were analysed iteratively. A kinetic mechanism based on simultaneous reactions has been proposed for the first peak and confirmed thermochemically by comparing the enthalpies deduced from iteration and that determined from experimental and calculated routes. The second peak of the thermogram was attributed to transformation of calcium sulfate hemihydrate into gypsum according to a dissolution/precipitation scheme. These phenomena are of order one and two, respectively.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Thermochimica Acta - Volume 452, Issue 1, 1 January 2007, Pages 71-75
Journal: Thermochimica Acta - Volume 452, Issue 1, 1 January 2007, Pages 71-75
نویسندگان
K. Antar, M. Jemal,