Membrane Reactors to Improve Selectivity in Multiple Reactions

7 Membrane Reactors to Improve Selectivity in Multiple Reactions 

In addition to using membrane reactors lo remove a reaction product in order to shift the equilibrium toward completion, we can use membrane reactors to increase selectivity in multiple reactions. This increase can be achieved by injecting one of the reactants along the length of the reactor. It is particularly effective in panial oxidation of hydrocarbons, chlorination, ethoxylation. hydrogenation, nitration, and sulfunation reactions to name a few.  

In the top two reactions, the desired product is the intermediate (e.g C2H4 However, because there is oxygen present, the reactants and intermediates c be completely oxidized to form undesired products COi and water. The des product in the bottom reaction is xylene. By keeping one of the reactants at low concentration, we can enhance selectivity. By feeding a reactant throug the sides of a membrane reactor, we can keep its concentration low. 

In the solved example problem on the CD-ROM. we have used a n brane reactor (MR) to continue the hydrodealkylation of mesitylene reactic Examples 6-7 and 6-8. In some ways, this CD example parallels the us MRs for partial oxidation reactions. We will now do an example for a difft reaction to illustrate the advantages of an MR for cenain types of reactioc 

Example 6-9 Membrane Reactor to Improve Selectivity irt Multiple Reactio 

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