Alternating motion of liquid in catalyst pores in a liquid/liquid–gas reaction with heat or gas production

Multiphase fixed-bed technologies

“…There are resulting uncertainties, which cannot be investigated completely, and there is nearly always a risk of constructing an industrial unit that cannot be operated appropriately. Really, mass transfer correlations give about 10-fold difference in mass transfer coefficients even in the simplest systems where only inert compounds, both gas and liquid are studied, let alone the problems related to the uneven wetting, "hot spots", change of physical properties along the catalyst bed, and the possible influence of the chemical reaction on mass transfer [26,27,30].…”

Intensivierung des Stofftransportes bei heterogen katalysierten Reaktionen durch Druckoszillation

“…D A T S E V I C H beschreibt das Verhalten einer gasbildenden Reaktion in porösen Katalysatoren. Anhand theoretischer Studien werden Bedingungen hergeleitet, unter denen es zur Pulsation im Porensystem kommt [5,6].…”

“…Der Druckgradient in der Flüssigphase setzt sich aus dem Druckgradienten in der Gasphase und dem Kapillardruckgradienten zusammen, dp l dr dp g dr À dp kap dr (6) wobei der Kapillardruck durch die Leverett-Korrelation gegeben ist [21].…”

Influence of Bubble Evolution on the Effective Kinetics of Heterogeneously Catalyzed Gas/Liquid Reactions. Part I: Reactions with Gaseous Products

“…One model, which describes the physical and mathematical basics of bubble evolution in porous catalyst particles, is the oscillation theory [8][9][10]. It considers multiphase reactions with gas or heat production where gas/vapor bubbles occur in catalyst pores due to a failure of mass or heat transfer.…”