Heat Transfer Effects in Facilitated Transport Liquid Membranes

Abstract

Various mathematical models have been developed to describe facilitated transport. There are two limiting regimes where steady-state analytical solutions are available; diffusion-limited (reaction equilibrium) and reaction-limited (frozen condition). For intermediate cases, numerical solutions are available. All of these models are valid for isothermal conditions. It is possible in practice that the system may not be isothermal. The gas streams on each side of the membrane may be at different temperatures and/or there can be heat of reaction effects. These effects can cause the total facilitated flux to deviate from the isothermal case.

The results of including temperature effects are incorporated in a dimensionless factor θ. θ is the facilitation factor for the non-isothermal case divided by the facilitation factor for the isothermal case. Results show that the imposition of a temperature gradient can cause a significant increase or decrease in the facilitated flux. In extreme cases, there can even be a reversal in the direction of the facilitated flux. The heat of reaction had no noticeable effect for the conditions studied.