Alkanes oxidative membrane reactors

Moreover, the membrane could be mounted as an interface between the apolar substrate and the polar oxidant in a membrane reactor, avoiding the use of any solvent. Dilution of the reagents by solvent and competition between solvent and reagents on the active sites can thus be avoided. In the countercurrent membrane reactor, the substrate and the oxidant are circulated at each side of the membrane and alkanes can be oxidized with peroxides without solvents. Of course, the system carries all of the other advantages of membrane reactors continuous operation and easy separation. 

Farrusseng D, Julbe A, and Guizard C. Evaluation of porous ceramic membranes as O2 distributors for the partial oxidation of alkanes in inert membrane reactors. Sep Purif Technol 2001 25 137-149. 

Figure 2.16. Top, O2 profiles generated in a membrane reactor for the partial oxidation of alkanes, (a) conventional MR (b) a chemical valve MR. Bottom, Evolution of permeance of the chemical valve membrane as a function of the ratio C3H8/O2 without any catalyst.

This article provides a brief survey of oxygen-ion transport membrane materials and their applications as membrane reactors in the selective oxidation of light alkanes. 

The first section of this chapter gives a brief survey of major membrane concepts and different membrane reactor configurations. Membrane materials are discussed in the second section. The third section will present the recent development of OITM reactors for selective oxidation of light alkanes. 

Espro, C., Arena, F.,Frusteri,F., Parmaliana, A.,2001. On the potential of the multifunctional three phase catalytic membrane reactor in the selective oxidation of light alkanes by Fej -HjOj Fenton system. Catalysis Today 67,247-256. 

The selective oxygenation of methane and light alkanes (Ci-Cj) by the Fe(II)/H202 Fenton system was performed in the three-phase catalytic membrane reactor, enabling simultaneous reaction and product separation. Frusteri et al. reported that Nafion-based catalytic membranes catalyze the selective oxidation of... 

Table 27.4. Membrane reactors using dense ceramic membranes for the oxidative dehydrogenation (ODH) of alkanes and other selective oxidations.

Figure 2.16 Schematic representation of the O2 profile generated in a tubular membrane reactor for the partial oxidation of alkanes (a) with a classical inert uniform porous membrane and (b) with the chemical valve membrane. Reproduced from [17]. With permission from Elsevier.

Hamel, C., T6ta, A., Klose, R, Tsotsas, E., and Seidel-Moigenstem, A. Analysis of single and multistage membrane reactors for the oxidation of short-chain alkanes— Simulation study and pilot scale ejqteiiments. Chem. Eng. Res. Des. 86, 753-764 (2008). 

Typical applications of zeolite membranes in reactors include i) conversion enhancement either by equilibrium displacement (product removal) or by removal of catalyst poisons/ inhibitors and ii) selectivity enhancement either by control of residence time or by control of reactant traffic. A large number of examples are reported and discussed in [49,50,52], Several of them are reported in fable 3. The use of a zeolite membrane as a distributor for a reactant has been attempted for the partial oxidation of alkanes such as propane to propene [137], or n-butane to maleic anhydride [138]. Limited performances were obtained because the back-diffusion of the alkane is hardly controllable with this type of microporous membrane [139]. 

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