کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
595831 1454025 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Preparation and characterization of a novel silica aerogel as adsorbent for toxic organic compounds
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Preparation and characterization of a novel silica aerogel as adsorbent for toxic organic compounds
چکیده انگلیسی

Hydrophobic and hydrophilic silica aerogels were prepared from cheap waterglass precursors via surface modification of wet gels, ambient pressure drying (APD) route and calcination treatment. Xerogel was also synthesized as a comparison to test the influence of microstructure on the adsorption behaviours. Ethanol (EtOH)/chlorotrimethylsilane (TMCS)/hexane solution was employed to replace the surface silanol groups (SiOH) with alkyl, and to prevent the condensation and shrinkage of the gel structure during the APD process. The synthesized silica aerogels, characterized by using Fourier transform infrared spectra (FTIR), nitrogen adsorption/desorption measurement, element analyses and differential scanning calorimeter (DSC), etc., are porous and translucent solids with surface area of 546–907 m2/g. The transition temperature from hydrophobic to hydrophilic was tested around 395 °C, which corresponds to the disappearance temperature of the CH3 peaks in FTIR. The materials were tested for adsorption capacities on rhodamine B (RhB) and dieldrin, which represented soluble and slightly soluble organic compounds, respectively. Results showed that the hydrophobic silica aerogel exhibited strong adsorption capacity on slightly soluble organic compounds while hydrophilic silica aerogel was much more effective on adsorbing soluble compounds from aqueous solution. Adsorption properties of the silica aerogel remain stable after 5 adsorption/desorption cycles.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Colloids and Surfaces A: Physicochemical and Engineering Aspects - Volume 347, Issues 1–3, 5 September 2009, Pages 38–44
نویسندگان
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