Silica-stabilized aluminas resistant to vanadium attack under severe high-temperature conditions

Journal Article · Wed Jun 01 00:00:00 EDT 1988 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(88)90108-X· OSTI ID:7052904

Murrell, L L; Dispenziere, Jr, N C

Silica stabilization of alumina by direct reaction of alkoxysilanes with the dehydrated surface of a 500/sup 0/C calcined silica-alumina cogel (5 wt% SiO/sub 2/ content) leads to a vanadium-tolerant support when exposed to severe high-temperature conditions. Vanadium present in heavy petroleum feedstocks is known to attack many conventional heterogeneous catalyst supports under regeneration conditions when coke deposits are removed under oxidizing conditions. The authors have found that it is the dispersed, vanadium oxide surface structure which causes the facile loss in surface area of conventional ..gamma..-alumina supports, with, or without, steam present under high-temperature conditions. The only supports which are stable to loss of surface area by a dispersed, vanadium oxide surface structure are (i) a silica-stabilized, transitional alumina which has been produced by reaction of the dehydrated, terminating hydroxyl structure of a boehmite-like, high-alumina content silica-alumina with tetraalkoxysilane, and (ii) a silica-stabilized alumina produced by reaction of boehmite itself with tetraalkoxysilane. A two-step preparation procedure was employed to prepare a bulk and surface, silica-stabilized alumina.

• Research Organization: Exxon Research and Engineering Co., Annadale, NJ (USA)
• OSTI ID: 7052904
• Journal Information: J. Catal.; (United States), Vol. 111:2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALUMINIUM OXIDES
CHEMICAL PREPARATION
STABILIZATION
CATALYST SUPPORTS
CATALYSTS
CONTROL
PETROLEUM
POISONING
REFINING
SILICA
VANADIUM
ALUMINIUM COMPOUNDS
CHALCOGENIDES
ELEMENTS
ENERGY SOURCES
FOSSIL FUELS
FUELS
METALS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PROCESSING
SILICON COMPOUNDS
SILICON OXIDES
SYNTHESIS
TRANSITION ELEMENTS
020400* - Petroleum- Processing
400201 - Chemical & Physicochemical Properties