Permeation properties of different aromatic substances in multicomponent aromatic/aliphatic pervaporation experiments

It has been shown that cross-linked copolyimides are very stable materials. They can be used for aromatic/aliphatic mixtures up to 150° C with an aromatic feed concentration of around 30%. By variation of the cross-linking agent it was shown in pervaporation experiments with a 5 component mixture that the total flux is decreasing with increasing chain length of the cross-linker, whereas the enrichment factor is slightly increasing.