On-line addition of catalyst in high-temperature reactors: high selectivity to olefins

Citation
As. Bodke et Ld. Schmidt, On-line addition of catalyst in high-temperature reactors: high selectivity to olefins, CATAL LETT, 63(3-4), 1999, pp. 113-120
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics","Chemical Engineering
Journal title
CATALYSIS LETTERS
ISSN journal
1011-372X → ACNP
Volume
63
Issue
3-4
Year of publication
1999
Pages
113 - 120
Database
ISI
SICI code
1011-372X(1999)63:3-4<113:OAOCIH>2.0.ZU;2-M
Abstract
By adding solutions containing catalyst salts to hot monolith catalysts dur ing partial oxidation processes, the salt decomposes instantly and is depos ited selectively near the front face. We have used this technique to deposi t extremely small amounts of Pt on alpha -Al2O3 monoliths during ethane oxi dation to olefins. We find that on this catalyst with H-2 addition, the sel ectivity to ethylene rises from similar to 65 to over 80% at an ethane conv ersion of similar to 60% and at complete O-2 conversion. We also examine th e addition of promoters including Sn, which gives improved performance comp ared to the Pt catalyst alone. This appears to be a general effect that cou ld be useful in preparing catalysts with different loadings and distributio ns in high-temperature processes. It can also be used for rapid and accurat e diagnosis of catalysts and additives and to modify catalysts on-line in s ituations where deactivation or catalyst loss occurs.