Publisher Summary The properties of a surface are influenced by the surface groups and the knowledge of their existence and of their chemistry are important for many technological processes This chapter examines the surface compounds on carbon—microcrystalline carbon, graphite, and diamond—on silica, on titania, and on alumina and silica–alumina Most important and best known among the surface compounds of carbon are those with oxygen and with sulfur Thus, two kinds of surface oxides are known Basic surface oxides are formed always when a carbon surface is freed from all surface compounds by heating in a vacuum or in an inert atmosphere and comes into contact with oxygen only after cooling to low temperatures Acidic surface oxides are formed when carbon is treated with oxygen a temperatures near its ignition point Unambiguous identification of carboxyl groups has been achieved by two reactions of the acyl chlorides: Friedel–Crafts reaction and Schmidt rearrangement

Chemical Identification of Surface Groups

During the past twenty years, the demand for high octane motor fuels has resulted in the installation of catalytic naphtha reforming capacity at a much higher rate than was forecasted by some of the

Catalytic Naphtha Reforming

An der Oberflache von Festkorpern sind haufig strukturfremde Atome oder Atomgruppierungen gebunden Die Chemie dieser „End-Gruppen” an der Festkorperoberflache wird an einigen Beispielen besprochen Bei Diamant und graphitischem Kohlenstoff und auch noch bei Siliciumdioxid sind die Fremdatome covalent gebunden, wahrend bei Titandioxid und Aluminiumoxid vorwiegend ionenartige Bindung der Oberflachengruppen vorliegt Oxide sind normalerweise mit einer monomolekularen Hydroxidschicht bedeckt Wertigkeitsanderungen der Metallatome fuhren zu Veranderungen der Aciditat der Oberflache; bei der Reduktion oberflachenstandiger Ti4+-Ionen bekommt die TiO2-Oberflache sauren Charakter

Funktionelle Gruppen an Festkörper-Oberflächen

Publisher Summary This chapter focuses on the solid oxides that are now used or that could be of potential use as acidic catalysts for hydrocarbon reactions in which the key steps involve transformations of carbon skeletons The chapter reviews representative methods for measuring surface acidity of solid catalysts Recommendations will then be made of the most appropriate methods from the standpoint of the needs of the investigator The final section is devoted to updating research activities dealing with individual solid catalysts Particular attention will be devoted to studies of acidities of unusually active catalysts such as crystalline zeolites, synthetic clays, and chlorinated aluminas The chapter defines the type of acidity that should be measured There are two classes of acids on surfaces of metal oxides: Lewis acids and Bronsted acids

Surface Acidity of Solid Catalysts

The chemistry and surface chemistry of fluorinated alumina

Studies of the hydrogen held by solids: X. Fluorided aluminas as acid catalysts

Studies of the hydrogen held by solids V. Investigation of platinum supported on alumina catalysts by exchange with deuterium gas

Influence of strongly chemisorbed gases on the rates of the para-hydrogen conversion and the H2—D2 exchange over nickel and copper+nickel alloy catalysts

F.E. Lutinski

Papers

Studies of the hydrogen held by solids: X. Fluorided aluminas as acid catalysts

Studies of the hydrogen held by solids V. Investigation of platinum supported on alumina catalysts by exchange with deuterium gas

Influence of strongly chemisorbed gases on the rates of the para-hydrogen conversion and the H2—D2 exchange over nickel and copper+nickel alloy catalysts