A Review on the Use and Stability of Supported Liquid Membranes in the Pervaporation Process

Abstract

In recent decades, pervaporation has been one of the most studied membrane separation processes and has undergone substantial progress and exciting breakthroughs due to its effectiveness in separating azeotropic mixtures and its low energy consumption. Often, pervaporation processes are operated using a solid membrane. However, the inherent limitations of solid membranes prompted the use of supported liquid membranes (SLMs), which are formed by immobilizing the liquid membrane with a porous supporting membrane. The idea of using a SLM in pervaporation is attractive because the rate of molecular diffusion in liquid is much higher than that in a solid membrane. This short article reviews the role of SLMs as a pervaporation membrane. The effects of operating parameters on the pervaporation performance of SLMs as well as concerns on the stability of SLMs and methods to improve its stability are discussed. At the end of this article, we propose the use of carbon nanotubes (CNTs) in SLMs and perform an evaluation of the commercial value of SLMs.

Keywords:

• Pervaporation
• supported liquid membrane
• carbon nanotubes

ACKNOWLEDGMENTS

The authors acknowledge fellowship support from the MyPhD program of the Ministry of Higher Education, Malaysia, and the USM. This research was also financially supported by a Universiti Sains Malaysia Research University (RU) grant, a USM Membrane Cluster Grant and a Fundamental of Research Grant Scheme (FRGS).