کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
43203 45958 2008 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hydrodechlorination of CCl4 over Pt/γ-Al2O3 prepared from different Pt precursors
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Hydrodechlorination of CCl4 over Pt/γ-Al2O3 prepared from different Pt precursors
چکیده انگلیسی

The platinum particle size on γ-Al2O3 prepared from different platinum precursors such as Pt(NH3)2(NO2)2, H2PtCl6, and K2PtCl6, and its effect on hydrodechlorination (HDC) of CCl4 with the variation of calcination temperatures was investigated. It concomitantly affects the products distribution and catalytic stability in HDC of CCl4. To verify the effects of platinum particle size with different platinum precursors on the product distribution, the catalysts have been characterized by HRTEM and CO chemisorption, FT-IR, and TP methods (TPR, TPD and TPSR). The catalysts with small platinum particles, which possess low coordination number and electron-deficient character, favor the complete dechlorination of CCl4 and produce CH4 more selectively. It could be due to the strong adsorption strength of CCl4 or the decreased activation energy of surface intermediates on small platinum particles. FT-IR studies reveal that the maximum peak position of linear-bonded CO shifted to the higher frequency with the increase of platinum particle size in all catalysts prepared from three different platinum precursors. While the selectivity to CH4 increased with the decrease in the platinum particle size, the total amount of carbonaceous species on the platinum particles was enhanced. The larger the platinum particle, the higher the selectivity to CHCl3 was obtained in all tested catalysts under the non-deactivating condition.

The maximum peak position of linear-bonded CO shifted to the higher frequency with the increase of platinum particle size in all catalysts prepared from three different platinum precursors. The small platinum particles, which possess low coordination number and electron-deficient character, favor the complete dechlorination of CCl4 and produce CH4 more selectively.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Catalysis A: General - Volume 334, Issues 1–2, 1 January 2008, Pages 156–167
نویسندگان
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