Secondary reactions during CO hydrogenation on zeolite-supported metal catalysts: influence of alkali cations

Journal Article · Thu Oct 01 00:00:00 EDT 1987 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(87)90311-3· OSTI ID:5270888

Oukaci, R; Wu, J C.S.; Goodwin, Jr, J G

The effect of neutralizing cations on the secondary reactions of the primary products from CO hydrogenation over ion-exchanged zeolite-supported Ru catalysts was investigated using zeolites with different alkali cations (Li/sup +/, Na/sup +/, K/sup +/, Rb/sup +/, Cs/sup +/). The transformation of olefins (propylene and butene) on the zeolites without the metal, under conditions similar to those used for CO hydrogenation, was also studied in order to understand the effect of the various constituents of the support, i.e., the Broensted acid sites generated during catalyst preparation and the alkali cations, on possible secondary reactions of the primary olefinic products. It was established that secondary acid-catalyzed reactions of these primary products can play a major role in shaping product selectivity during CO hydrogenation over zeolite-supported catalysts. Depending on the concentration and the strength of the acid sites, various competitive reaction paths can be observed for the transformation of the olefinic compounds. These include isomerization, oligomerization, polymerization, and cracking. The strength of the acid sites was found to be strong function of the nature of the neutralizing alkali cations remaining in the zeolite. The presence of Li/sup +/ produced the strongest acid sites resulting in more oligomerization over LiHY than even HY. Acid site strength decreased with the molecular weight of the alkali cation used.

• Research Organization: Univ. of Pittsburgh, PA (USA)
• DOE Contract Number: FG22-83PC60805
• OSTI ID: 5270888
• Journal Information: J. Catal.; (United States), Vol. 107:2
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
CARBON MONOXIDE
METHANATION
ZEOLITES
CATALYTIC EFFECTS
COMPARATIVE EVALUATIONS
BUTENES
CESIUM
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CRACKING
FISCHER-TROPSCH SYNTHESIS
HYDROGENATION
ISOMERIZATION
LITHIUM
POLYMERIZATION
POTASSIUM
PROPYLENE
REACTION INTERMEDIATES
RUBIDIUM
RUTHENIUM
SODIUM
ALKALI METALS
ALKENES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
DECOMPOSITION
ELEMENTS
HYDROCARBONS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
KINETICS
MATERIALS
METALS
MINERALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PLATINUM METALS
PYROLYSIS
REACTION KINETICS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENTS
010408* - Coal
Lignite
& Peat- C1 Processes- (1987-)