کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
580788 1453156 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Adsorption of acids and bases from aqueous solutions onto silicon dioxide particles
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
پیش نمایش صفحه اول مقاله
Adsorption of acids and bases from aqueous solutions onto silicon dioxide particles
چکیده انگلیسی
The adsorption of acids and bases onto the surface of silicon dioxide (SiO2) particles was systematically studied as a function of several variables, including activation conditions, contact time, specific surface area, particle size, concentration and temperature. The physical properties of SiO2 particles were investigated, where characterizations were carried out by FT-IR spectroscopy, and morphology was examined by scanning electron microscopy (SEM). The SEM of samples showed good dispersion and uniform SiO2 particles with an average diameter of about 1-1.5 μm. The adsorption results revealed that SiO2 surfaces possessed effective interactions with acids and bases, and greatest adsorption capacity was achieved with NaOH, where the best fit isotherm model was the Freundlich adsorption model. The adsorption properties of raw SiO2 particles were further improved by ultrasonication. Langmuir monolayer adsorption capacity of NaOH adsorbate at 25 °C on sonicated SiO2 (182.6 mg/g) was found to be greater than that of the unsonicated SiO2 (154.3 mg/g). The spontaneity of the adsorption process was established by decreases in ΔGads0, which varied from −10.5 to −13.6 kJ mol−1, in the temperature range 283-338 K.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Hazardous Materials - Volume 172, Issues 2–3, 30 December 2009, Pages 978-985
نویسندگان
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