Kinetics of Gas-Liquid Reactions on Solid Catalysts

Multiphase reactors, wherein gas and liquid reactants are contacted in the presence of a solid catalyst, are vitally important in many areas of industrial chemistry. They are not only used in refinery and petrochemical processes (hydrodesulphurization, hydrogenation, etc.) but also for the production of preliminary products (for polymers etc.) as well as of fine chemicals. Selected examples are examined in 

Section 6.8 (clean fuels by hydrotreating) and in Section 6.17 (production of the fine chemical menthol). 

we will only examine the basic kinetic equations of gas-liquid reactions on solid catalysts, taking as example the simple reaction of a gaseous reactant A that reacts after dissolution in the liquid phase with a liquid reactant B (va = Vb = —1) to a liquid product P  

In common multiphase reactors mass transfer resistances frequently lead to a decrease of the effective reaction rate compared to the chemical (intrinsic) rate. In addition, many multiphase reactions like oxidations or hydrogenations are highly exothermic. Consequently, heat removal may also be important. 

mass transfer of gaseous reactant A from the main body of the gas phase (bubbles etc.) to the gas liquid interphase and dissolution in the liquid phase  

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