Cel The key species in the surface chemistry of carbon dioxide has been shown to be the anionic bent CO2{delta-}(a) state. Activation of carbon dioxide can be achieved through modification by alkali metals of both single crystal metal surfaces such as Cu(110) and Ni(110), polycrystalline copper film surfaces and single crystal oxides, such as Cr2O3(111). The alkali metals have included caesium, sodium and potassium. Through a combination of surface sensitive spectroscopies (EELS, XPS, UPS and Raman) assignments have been made of species participating in surface reactions of CO2, with individual reaction steps isolated through judicious use of low temperatures for delineating the more facile reactions. Although interest in surface modification by alkali metals is of paramount interest to understanding the real catalyst, the interaction of CO, CO2 and O2 with the alkali metal itself (caesium) has emphasised the significance of oxygen states in the chemistry of both CO and CO2: reaction pathways are controlled by which oxygen state is present. A most significant results has been the successful coupling of carbon dioxide with methyl radicals to generate acetate species. These have been recognised through both surface spectroscopic studies (HREELS and XPS) and also through thermal desorption and mass spectrometry. The limitations of the experimental technique of Temperature Programmed Desorption in studies of methanol decomposition at copper surfaces have been highlighted with slower reaction pathway to formate being difficult to delineate, formaldehyde desorption being seen as the main reaction pathway. A clear message that has emerged from this project is not only the subtle nature of CO2 catalysis but also the limitations of attempting to predict the outcome of the chemistry likely to occur when CO2 is coadsorbed with other molecules, on the basis of the chemistry of the separate components. We are beginning to unravel the mechanistic details at the molecular level.CO2 chemistry needs to be developed because CO2 is an important waste material that should be reintroduced into chemical processes.Recently it has been shown that CO2 plays a key role in methanol synthesis. It is our goal to unravel the mechanistic details of methanol synthesis and CO2 chemistry on catalyst surfaces in general by a concerted surface science approach using in situ surface sensitive spectroscopies over a wide range of pressure-ultra high vacuum up to 10 bar - and thus bridging the "pressure gap". We start with well ordered model systems and modify these by introducing disorder to see the effect of active sites, giving insights into the details of the reaction mechanism of methanol synthesis and accordingly improvements of the industrial catalytic process. We will also use our knowledge about CO2 activation from ultra high vacuum studies to try to create a new catalytic model system to form carboxylic acids by reaction between CO2 and alkanes. Dziedzina nauki natural scienceschemical sciencesorganic chemistryorganic acidsnatural scienceschemical sciencesinorganic chemistryalkali metalsnatural scienceschemical sciencesorganic chemistryalcoholsnatural scienceschemical sciencescatalysisnatural scienceschemical sciencesanalytical chemistrymass spectrometry Program(-y) FP3-BRITE/EURAM 2 - Specific programme (EEC) of research and technological development in the field of industrial and materials technologies, 1990-1994 Temat(-y) 2.2.3 - Integrated approach to chemical and process engineering Zaproszenie do składania wniosków Data not available System finansowania CSC - Cost-sharing contracts Koordynator University of Wales, Cardiff Wkład UE Brak danych Adres CF1 3TB Cardiff Zjednoczone Królestwo Zobacz na mapie Koszt całkowity Brak danych Uczestnicy (3) Sortuj alfabetycznie Sortuj według wkładu UE Rozwiń wszystko Zwiń wszystko HEINRICH-HEINE-UNIVERSITÄT DÜSSELDORF Niemcy Wkład UE Brak danych Adres UNIVERSITÄTSTRAßE 1 40225 DÜSSELDORF Zobacz na mapie Koszt całkowity Brak danych RUHR-UNIVERSITÄT BOCHUM Niemcy Wkład UE Brak danych Adres UNIVERSITÄTSTRAßE 150 4630 BOCHUM Zobacz na mapie Koszt całkowity Brak danych Università degli Studi di Roma Włochy Wkład UE Brak danych Adres Via Orazio Raimondo 00173 Roma Zobacz na mapie Koszt całkowity Brak danych
