کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6454522 1418817 2017 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Studies on three-way catalysis with supported gold catalysts. Influence of support and water content in feed
ترجمه فارسی عنوان
مطالعات کاتالیزوری سه طرفه با کاتالیزورهای طلایی پشتیبانی شده. تأثیر حمایت و محتوای آب در خوراک
کلمات کلیدی
کاتالیزای سه طرفه، طلا، نفوذ حمایت، نفوذ آب، تعامل واکنش دهنده،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
چکیده انگلیسی


- Monometallic Au catalysts strong in CO oxidation, weak in NO reduction.
- Propene delays CO oxidation drastically.
- Poisoning of CO oxidation strongly dependent on support − rather minor on CeZrOx.
- Poisoning of CO oxidation by propene strong in dry feed, alleviated in wet feed.

The potential of gold for the reactions of three-way catalysis was examined by converting a model exhaust consisting of 1.1% CO, 0.1% propene, 0.1% NO, O2 (0.95% - stoichiometric, 0.85% - rich, or 1.05% - lean), and water (10% or none) over catalysts containing 1-2 wt-% Au supported on Al2O3, La-Al2O3, TiO2, and CeZrOx supports. For comparison, CO and propene were also reacted stoichiometrically with oxygen in absence of further reactants, likewise, reduction of NO with CO was examined. It was found that propene is a strong poison for CO oxidation, but the intensity of the poisoning effect depended on the support (Al2O3 > La-Al2O3 > TiO2 > CeZrOx). The poisoning was strongest in dry feed but was partly alleviated in moist feed. NO was poorly converted both in the TWC mixture and in binary feed. In the model exhaust, NO conversion resulted in significant N2O formation at low temperatures, but selectivity to N2 increased with temperature. Despite poisoning by propene, Au/CeZrOx outperformed a commercial reference catalyst in CO and propene oxidation. Calcination in moist dilute air at 923 K inflicted only moderate damage to the Au catalysts. Over Au/CeZrOx, CO oxidation in stoichiometric feed was not significantly affected at all, but the poisoning effect of propene became more severe in the TWC model feed. Analogous treatment at 1223 K resulted in inacceptable damage to all reactions involved and on all supports.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Catalysis B: Environmental - Volume 203, April 2017, Pages 572-581
نویسندگان
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