Trickle-Bed Reactor Three-Phase Reactions

A trickle-bed reactor is a three-phase (gas + liquid + solid) reactor in which the solid 

The limiting reactant is usually B, which may be volatile or nonvolatile. 

Trickle-bed reactors are used in catalytic hydrotreating (reaction with H2) of petroleum fractions to remove sulfur (hydrodesulfurization), nitrogen (hydrodenitrogena-tion), and metals (hydrodemetallization), as well as in catalytic hydrocracking of petroleum fractions, and other catalytic hydrogenation and oxidation processes. An example of the first is the reaction in which a sulfur compound is represented by diben-zothiophene (Ring and Missen, 1989), and a molybdate catalyst, based, for example, on cobalt molybdate, is used  

24-1 For a gas-liquid reaction, under what main condition would a relatively large liquid holdup be required in a reactor, and what type of reactor would be used Explain briefly. 

24-2 Consider the removal of C02 from a gas stream by treatment with an aqueous solution of monoethanolamine (MEA) in a countercurrent-flow, packed tower operating at 25°C and 10 bar. The reaction is 

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