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The present work deal with a comparative study of two kinetics models of ethanol conversion by steam reforming for pure hydrogen generation in a Pd-Ag based membrane reactor. For this purpose, a mathematical model describing the reaction and separation phenomena that take place simultaneously in the membrane reactor was developed. The numerical solution of the set of differential equations constituting the obtained model allows us to quantify the process performance over both and catalysts. According to the obtained results, it was found that the performance of the ethanol steam reforming process depends strongly on the catalyst nature. In addition, the process's strongly sensitive to the used operating conditions, especially hydrogen partial pressure in permeate and in reaction sides, in which a good correlation and a synergistic effect between these parameters could be established. Under the optimal operating conditions, the quantity of hydrogen recovered when using the is three times greater than that obtained by using the catalyst.

In this paper, we focus to highlighting the positive role of periodic operation which can be played for performance improvement of a hydrogen separator reactor integrating a palladium membrane. For this subject, a mathematical approach describing the pure hydrogen production and its pumping during methanol steam reforming process is developed to simulate the effect of the reactor inlet feed and of sweeping gas on reactor performance. The main findings show that the reactor responses exhibit a periodic phenomenon. So, in order to achieve a yield improvement higher than that obtained under the steady state conditions, it is necessary to intensify the process by using a periodic operation. Therefore, when the reactor is simultaneously forced by running the feed composition in the reaction side and by the sweeping gas in the permeate side using a symmetric square function, the magnitude of improvement of methanol conversion and pure hydrogen recovery are higher than that achieved at steady state operation. This is due to the dual effect synergistic, which is could be brought by the potential periodic mode of the inputs coupling.

The use of filamentous catalysts for innovative design of chemical reactors with structured catalytic beds is discussed in detail. The fluid dynamics attained in such reactors avoid transport limitations (mixing or heat- and mass-transfer) and increase reactor performance/safety.