Cyclohexane hydrogen recovery

Itoh, N., Tamura, E., Hara, S., Takahashi, T., Shono, A., Satoh, K. and Namba, T., 2003. Hydrogen Recovery from Cyclohexane as a Chemical Hydrogen Carrier Using a Palladium Membrane Reactor. Catalysis Today, 82(1-4) 119-125. 

Itoh,N.,E.Tamura,S.Hara,T.Takahashi, A. Shono,K.SatohandT.Namba Hydrogen recovery from cyclohexane as a chemical hydrogen carrier using a palladium membrane reactor, Catal. Today, 82,119-125 (2003). 

Separation of benzene/cyclohexane mixture is investigated most extensively. This is not surprising because separation of this mixture is very important in practical terms. Benzene is used to produce a broad range of valuable chemical products styrene (polystyrene plastics and synthetic rubber), phenol (phenolic resins), cyclohexane (nylon), aniline, maleic anhydride (polyester resins), alkylbenzenes and chlorobenzenes, drugs, dyes, plastics, and as a solvent. Cyclohexane is used as a solvent in the plastics industry and in the conversion of the intermediate cyclohexanone, a feedstock for nylon precursors such as adipic acid. E-caprolactam, and hexamethylenediamine. Cyclohexane is produced mainly by catalytic hydrogenation of benzene. The unreacted benzene is present in the reactor s effluent stream and must be removed for pure cyclohexane recovery. 

Finally, these aqueous colloidal solutions were used as catalysts for the hydrogenation of simple olefins and arenes with Roucoux et al. [107], These nanocatalysts appeared efficient in mild conditions, evidencing that these materials are active despite the evolution of their environment related to their dissolution into water. For example, octene and dodecene were fully converted into the corresponding alkanes (r.t 1 bar H2) with moderate activities. An increase in the hydrogen pressure (P(H2) = 10 bar) was not detrimental for the stability of the colloidal suspension. The complete hydrogenation of toluene into cyclohexane was observed overnight with Ru/PTA, whereas 60% of /n-methoxymethylcyclohexane was formed from methoxymethylanisole. Nevertheless, preliminary recycling tests showed that an improvement of the stability and recovery of these materials was necessary to increase their interest in catalysis. 

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