Co-Polyamide with 2-Pyridylquinoline Moieties in the Main Chain and Its Metal-Polymer Complex with Cu(II) for Toluene Recovery: Synthesis, Structure, Physicochemical and Transport Properties

AbstractCurrently, recovery of organic solvents using eco-friendly methods is one of the primary industrial tasks. Separation of liquid media by pervaporation offers more advantages as compared to conventional purification methods, such as distillation, in view of low energy and resource consumption. This work is focused on the study of novel copolyamide with 2-pyridylquinoline-4,7-dicarboxylic acid moieties in the main chain and its metal-polymer complex in the form of dense films. At present, metal-polymer complexes are growing in importance among membranes. The analysis of mechanical and thermal properties of the films also supports their high operational characteristics. Comprehensive studies of the structure of the obtained films show that both samples have a rigid and dense structure, but the metal-polymer complex is characterized by an increased surface roughness. The hypothesis of supramolecular association between polymers and separated liquids (methanol and toluene) is confirmed by quantum chemical calculations. Transport properties of novel polymers in pervaporation of toluene/methanol mixtures are examined and compared with the literature data. Both polymer films demonstrate an outstanding selectivity toward toluene in the separation of binary mixtures. The developed films have higher values of total flux and separation factor as compared to the most of known membranes.