Mechanism of catalytic isomerization of xylenes: kinetic and isotopic studies

Journal Article · Wed Mar 15 04:00:00 EST 1978 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(78)90271-3· OSTI ID:5120189

Cortes, A; Cormia, A

The vapor-phase isomerization of xylenes over a silica-alumina catalyst containing 4 wt% nickel has been investigated in the presence of excess hydrogen at 400/sup 0/C and pressures up to 15 atm. The results clearly indicate that the three isomers are interconverted via the consecutive reaction, ortho reversible meta reversible para. Hydrogenolysis to toluene and disproportionation to trimethylbenzenes are the two major competing reactions. Additional experiments carried out with deuterium-labeled p-xylene show that the isomerization proceeds almost exclusively by intramolecular 1,2 shifts of the methyl groups around the aromatic ring.

• Research Organization: CSIC, Madrid
• OSTI ID: 5120189
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 51:3; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AROMATICS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DEUTERIUM
HYDROCARBONS
HYDROGEN ISOTOPES
ISOMERIZATION
ISOTOPES
KINETICS
LIGHT NUCLEI
MINERALS
NICKEL ADDITIONS
NICKEL ALLOYS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
STABLE ISOTOPES
XYLENES