Isomerization reactions, zeolite membrane

Separation of isomers is an application where zeolite membranes could be specifically interesting because of their well-defined pores that lead to molecular sieving effects. An application that is often considered is the xylene isomerization and related reactions. 

Table 10.2 Performance of several zeolite membrane reactors in the xylene isomerization reaction. 

Membrane reactors provide opportunities for overcoming thermodynamic limits on the maximum attainable conversion of reversible reactions. A simple membrane reactor model has been employed to investigate the performance of Cs/C6 hydroisomerization process on zeolites and compare it to a state-of-the-art total isomerization (TIP) process. A RON of 88.0 was obtained, slightly higher and promising compared to the TIP process with RON of 86. 

Other authors studied the dehydrogenation of cyclohexane to benzene" and the cis to trans isomerization of piperylene. Both reactions were carried out in a vapour phase batch reactor at low temperature with a catalytic polymeric membrane, a composite polyethylacrylate polymer built-in with zeolite 13X containing Ni or Ti" or Co as catalyst. The reactor was fed with pure reactants in both cases. The authors developed a simple transient... 

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