Modelling metal centres, acid sites and reaction mechanisms in microporous catalysts
نویسندگان
چکیده
منابع مشابه
Modelling metal centres, acid sites and reaction mechanisms in microporous catalysts.
We discuss the role of QM/MM (embedded cluster) computational techniques in catalytic science, in particular their application to microporous catalysis. We describe the methodologies employed and illustrate their utility by briefly summarising work on metal centres in zeolites. We then report a detailed investigation into the behaviour of methanol at acidic sites in zeolites H-ZSM-5 and H-Y in ...
متن کاملComputer Modelling of Microporous and Oxide Catalysts
Computer modelling provides a range of powerful tools for exploring catalytic processes at the molecular level. In particular, modelling allows detailed characterisation of active site structures and of reaction mechanisms; and the techniques are particularly powerful when used in conjunction with experimental investigations. We will illustrate the current state-of-the-art of this field by summ...
متن کاملActive Sites and Mechanism for the Water-Gas Shift Reaction on Metal and Metal/Oxide Catalysts
Current industrial catalysts for the water-gas shift reaction are commonly mixtures of Fe-Cr and Zn-Al-Cu oxides, used at temperatures between 350-500oC and 180250oC, respectively. These oxide catalysts are pyrophoric and normally require lengthy and complex activation steps before usage. Improved catalysts are being sought, particularly for lower temperature (e.g., at T<150oC, equilibrium lowe...
متن کاملSize-selective Lewis acid catalysis in a microporous metal-organic framework with exposed Mn2+ coordination sites.
Treatment of selected aldehydes and ketones with cyanotrimethylsilane in the presence of the microporous metal-organic framework Mn3[(Mn4Cl)3BTT8(CH3OH)10]2 (1, H3BTT = 1,3,5-benzenetristetrazol-5-yl) leads to rapid conversion to the corresponding cyanosilylated products. The transformation is catalyzed by coordinatively unsaturated Mn2+ ions that serve as Lewis acids and lead to conversion yie...
متن کاملThe Strength of Brønsted Acid Sites in Microporous Aluminosilicates
Ensemble-averaged deprotonation energies (DPE) derived from periodic density functional theory models are insensitive to the location of isolated Al atoms and associated protons and similar among microporous aluminosilicates (i.e., zeolites) with different crystalline frameworks (MFI, BEA, FER, MOR, CHA, FAU). These DPE values are 1201 ± 11 kJ mol−1 after correcting for systematic artifacts of ...
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: Faraday Discussions
سال: 2016
ISSN: 1359-6640,1364-5498
DOI: 10.1039/c6fd00010j