Thermal Treatments and Disturbances

As will be pointed out later, catalysts and membranes may become gradually deactivated and, when this occurs, they need to be regenerated often by some combustion process using dilute oxygen. In cases where coke deposit becomes significant on the cat yst or the membrane and needs to be removed by combustion, the membrane reactors are potentially subject to thermochemical cycling as part of the normal operation. 

Other potential temperature variations or cycling may also occur as a result of feed or control disturbances. Thus it is important to ensure that the temperature of the system is in control so that no damage is done to the membrane, catalyst or other system components. It is well known, for example, that [Ktlladium can become embriuled under hydrogen-rich conditions particularly at a temperature near 300 or so. Some remedy in the case of palladium is to introduce certain metal such as silver as the alloying element. 

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