General Transport Equations High Pressures

The solution of equation (1.37) at the high pressure limit is given in section 1.8. Another transport equation which is less general is given below. This equation is very useful particularly for the fall-off region and to compare data with other dissociation systems (see section 1.1). The system is described in terms of variable energy, with a specific dissociation rate constant k(E,). With this notation one obtains at general pressures... 

Eq. VI - 74 is the basic equation for liquid transport and it is the same as that for gas transpon (see eq. VI - 46) and vapour transpoit. However, due to the (high) interaction between organic liquids and polymer the permeability coefficient Pj is dependent on composition and temperature. Both solubility and diffusivity are concentration and temperature dependent as have been discussed in chapter V Eq. VI - 74 illustrates the important parameters involved, the permeabilitj coefficient is a membrane- or material-based parameter. Other parameters of interest are the effective membrane thickness I and the partial pressure difference Apj. The permeation rate is inversely proportional to the membrane thickness and proponional to the partial pressure difference across the membrane. In general eq. VI - 74 can be w ritten as... 

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