کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
63728 48249 2016 9 صفحه PDF سفارش دهید دانلود کنید
عنوان انگلیسی مقاله ISI
Tuning of textural properties of germanosilicate zeolites ITH and IWW by acidic leaching
ترجمه فارسی عنوان
تنظیم خواص بافتی زئولیت های germanosilicate ITH و IWW توسط شستشوی اسیدی
کلمات کلیدی
خواص بافتی؛ با؛ IWW؛ Degermanation
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
چکیده انگلیسی

The possibility to adjust textural properties of ITH and IWW zeolites by the variation of conditions (e.g. temperature, pH, duration) of acidic leaching was shown. While the growth of the temperature of acid treatment caused the increasing amount of leached Ge atoms and enhancing volumes of both micro and mesopores at 80 °C, the mesopore volume in ITH (Si/Ge = 3.4 and 5.8) and IWW (Si/Ge = 3.3) zeolites changed with the duration of the treatment (pH = 2; T = 80 °C) as follows: 96 h < 1 h < 24 h. Independently on the chemical composition and zeolite topology, the treatment of germanosilicate zeolites at pH = 2–7 resulted in development of both micro and mesoporosity accompanied by the extraction of substantial amount of Ge atoms, while the increasing acidity up to pH = 0 resulted in some reduction of Ge extraction and in the development of mesopores at maintained value of micropore volume when compared with initial germanosilicates. The higher activity (i.e. number of reactant molecules converted per active site) of germanosilicate with modified micro-mesoporous channel system in comparison with parent IWW zeolite in esterification of levulinic acid was attributed to enhanced accessibility of active sites.

New materials with hierarchical pore system can be prepared by acidic treatment of germanosilicate zeolites. Varying temperature and duration of the treatment allows tuning their textural characteristics. Micro-mesoporous germanosilicates show enhanced accessibility of active sites.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Energy Chemistry - Volume 25, Issue 2, March 2016, Pages 318–326
نویسندگان
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