کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
584960 877902 2007 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Removal of aqueous lead ions by hydroxyapatites: Equilibria and kinetic processes
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
پیش نمایش صفحه اول مقاله
Removal of aqueous lead ions by hydroxyapatites: Equilibria and kinetic processes
چکیده انگلیسی
The capacity of hydroxyapatite (HAp) to remove lead from aqueous solution was investigated under different conditions, namely initial metal ion concentration and reaction time. The sorption of lead from solutions containing initial concentrations from 0 to 8000 mg/L was studied for three different HAp powders. Soluble Pb and Ca monitoring during the experiment allows characterizing the mechanism of lead uptake. Dissolution of calcium is followed by the formation of a solid solution, PbxCa10−x(PO4)6(OH)2, with a Ca/P ratio decreasing continuously. Langmuir-Freundlich classical adsorption isotherms modeled adsorption data. The adsorption capacities calculated from this equation vary from 330 to 450 mg Pb/g HAp for the different solids. Modeling of the sorption process allows to determine theoretical saturation times and residual lead concentrations at equilibrium.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Hazardous Materials - Volume 139, Issue 3, 31 January 2007, Pages 443-446
نویسندگان
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