Operando QEXAFS Study of Pt–Fe Ammonia Slip Catalysts During Realistic Driving Cycles
نویسندگان
چکیده
Abstract Bifunctional Fe–Pt ammonia slip catalysts were studied by operando quick-scanning extended X-ray absorption fine structure spectroscopy (QEXAFS) under conditions mimicking rapid temperature variations that occur in an automotive exhaust gas aftertreatment system during real driving. Two catalysts, Pt/Al 2 O 3 and Fe-ZSM-5, tested individually, as mixtures dual bed arrangements. Applying QEXAFS allowed to track changes of active metal state with high time resolution. It uncovered a strong dependence the on reaction catalyst layout. For example, proximity platinum stabilized iron species their more oxidized led higher Fe-ZSM-5 activity. On contrary, isolated susceptible overreduction which deactivation low selectivity. The use transient influence non-equilibrium phenomena catalytic performance industrially relevant conditions. Specifically, effect storage increase activity was shown. This also accompanied elevated N production not observed tests gradual heating. Additionally, unusually NO x selectivity detected for these Lastly, tracking dynamic disclosed did grow directly but rather depended oxidation Fe surface concentration ammonia.
منابع مشابه
the effect of traffic density on the accident externality from driving the case study of tehran
در این پژوهش به بررسی اثر افزایش ترافیک بر روی تعداد تصادفات پرداخته شده است. به این منظور 30 تقاطع در شهر تهران بطور تصادفی انتخاب گردید و تعداد تصادفات ماهیانه در این تقاطعات در طول سالهای 89-90 از سازمان کنترل ترافیک شهر تهران استخراج گردید و با استفاده از مدل داده های تابلویی و نرم افزار eviews مدل خطی و درجه دوم تخمین زده شد و در نهایت این نتیجه حاصل شد که تقاطعات پر ترافیک تر تعداد تصادفا...
15 صفحه اولCobalt-based Catalysts for Ammonia Decomposition
An effect of promoters such as calcium, aluminium, and potassium oxides and also addition of chromium and manganese on the structure of cobalt catalysts was examined. Studies of the catalytic ammonia decomposition over the cobalt catalysts are presented. The studies of the ammonia decomposition were carried out for various ammonia-hydrogen mixtures in which ammonia concentration varied in the r...
متن کاملRealistic Driving Trips For Location Privacy
Simulated, false location reports can be an effective way to confuse a privacy attacker. When a mobile user must transmit his or her location to a central server, these location reports can be accompanied by false reports that, ideally, cannot be distinguished from the true one. The realism of the false reports is important, because otherwise an attacker could filter out all but the real data. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Topics in Catalysis
سال: 2022
ISSN: ['1022-5528', '1572-9028']
DOI: https://doi.org/10.1007/s11244-022-01718-y