Hydrodynamics and Mass Transfer in a Pellet String Reactor for Gas‐Liquid‐Solid Reactions

Abstract

In dieser Arbeit wurden die Hydrodynamik einer Gas/Flüssig-Zweiphasenströmung und erzielbare Stofftransportraten in einem Perlschnurreaktor charakterisiert. Die Katalysatorpackung im Reaktor besteht aus runden Kanälen mit einem Kanaldurchmesser von 1,41 mm, in die kugelförmige Katalysatorpartikel mit einem Durchmesser von 0,8 mm integriert sind. Bei gleichzeitig ablaufender Reaktion (Flüssigphasenhydrierung von a-Methylstyrol) konnten volumetrische Gesamtstoffdurchgangskoeffizienten für Wasserstoff zwischen 0,8 und 5,5 s -1 ermittelt werden. Aufgrund der hohen erzielbaren Stofftransportraten und des einfachen Aufbaus können Perlschnurreaktoren schnell in der Industrie implementiert werden und tragen zur Generierung hocheffizienter Reaktionsapparate bei.In this work, a pellet string reactor was characterized with respect to hydrodynamics and mass transfer. The catalyst packing consists of a cylindrical channel with a diameter of 1.41 mm, which was filled with spherical catalyst particles, having an outer diameter of 0.8 mm. Under reaction conditions (liquid phase hydrogenation of a-methylstyrene) overall (gasliquid-solid) volumetric mass transfer coefficients for hydrogen between 0.8 and 5.5 s -1 were computed. Due to high mass transfer rates and simple reactor geometry, pellet string reactors can be applied in industry as highly efficient reaction units. Abbildung 3. Strömungskarte für den untersuchten Perlschnurreaktor (d K = 1,5 mm, d P = 0,8 mm, p = 1,1 MPa, T = 298,15 K, w AMS = 0,2, Stickstoff).Abbildung 4. Scheinbare kinetische Konstanten bei verschiedenen Reaktionstemperaturen im untersuchten Perlschnurreaktor (u G,S = 1,18 m s -1 , u L,S = 0,05 m s -1 ).

A porous structured reactor for hydrogenation reactions

“…Among many others, trickle bed and monolithic reactors [8] [9] [10], micro-reactors [11] [12] and catalyst coated highly porous structures, like metal and ceramic foams [13] [14] [15], were studied and described in the literature. A c c e p t e d M a n u s c r i p t …”

Continuous Hydrogenation of L‐Arabinose and D‐Galactose in a Mini Packed‐Bed Reactor

“…The particles form a relatively open bed structure, resulting in a low pressure drop. Ideally, segmented flow of gas and liquid is generated to allow for an intense catalyst wetting and high mass transfer rates . Further advantages include low liquid holdup and a high surface‐to‐volume ratio.…”

Process Intensification in Chemical Reaction Engineering

“…However, an efficient and reliable method to deposit industrial catalysts is still a central challenge in the application of these novel catalyst structures. An alternative could be the integration of industrial catalyst particles into structures which guide the flow in so-called composite structured catalysts [31][32][33]. Particles, pellets, extrudates and even foams are suggested as internals.…”