Kinetic demixing

Kinetic demixing stems from activity differences established between the opposite surfaces. These differences can be produced in various ways. In this section, we applied buffers with different chemical potentials. Other possibilities are activity changes through temperature gradients and activity changes through stress gradients. These situations will be discussed in Sections 8.5 and 8.6. 

S02) easily reacts with the same membrane components, and need therefore to be removed before the separation unit. The material designer must also consider possible evaporation of membrane components. The high temperature in combination with steam can lead to increased evaporation by metal-hydroxy components. Kinetic demixing seems to be an unavoidable phenomena originating from difference in diffusivity of the metal components in thermodynamic potential gradients... 

The quantity of ambipolar conductivity is widely used for the analysis of -> electrolytic permeability of -> solid electrolytes, caused by the presence of electronic conductivity. Other important cases include transient behavior of electrochemical cells and ion-conducting solids, dense ceramic membranes for gas separation, reduction/ oxidation of metals, and kinetic demixing phenomena [iv]. In most practical cases, however, the ambipo-... 

D. Monceau, C. Petot and E. Petot, Kinetic demixing profile calculation under a temperature gradient in multi-component oxides. /. Europ. Ceram. Soc., 9 (1992) 193-204. 

One of the first assumptions in our economic considerations was that all the technological challenges were met. This remains, at the moment of writing, uncertain. In the above discussion, a number of issues have passed, such as sealing technology, thermodynamic phase stability of the cubic perovskite versus brownmillerite, and kinetic demixing. In relation to this, we have not mentioned creep resistance as yet. For SCF, this was shown to be very low [40], which is likely to be the case for BSCF as well. 

It is known that the MIEC membranes inevitably undergo a kinetic demixing/ decomposition process under oxygen separation conditions. When an oxygen ion conductive membrane is exposed to an oxygen chemical potential... 

Feo sOa-a oxygen separation membranes effects of kinetic demixing/decomposition and impurity segregation. /. Membr. Set, 344, 101-106. 

Figure 7-L Schematic illustration of kinetic demixing of the oxide solid solution (AyB)i.gD in a oxygen potential gradient.

Monceau, D., Petot, C., and Petot E., Kinetic demixing profile calculation imder a temperature gradient in... 

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