The wide possibilities of designing a chemical structure and creating complexes with transition metals make polymers of heteroaromatic structure interesting objects, from both scientific and practical aspects. In this work, modern biquinoline-containing polymers, namely polyester amide (PEA) and its metal–polymer complex (PEA–Cu(I)), were synthesized and used to form dense flat membranes. A comparative study of their morphology, same physical properties (density, free volume, and contact angles), and thermomechanical characteristics was carried out. The transport properties of the modern membranes were studied during pervaporation, to solve a problem of n-heptane isolation from its binary mixtures with thiophene and methanol. It was shown that only the PEA membrane is selective for the separation of thiophene impurities from the mixture with n-heptane. In pervaporation of methanol/n-heptane mixture, the РЕА–Cu(I) membrane exhibits significantly higher pervaporation separation index, as compared with that of the РЕА membrane.

No abstract

The process of dehydration of n-butanol as one of the most used solvents and a biofuel base has been studied by a membrane separation method with the use of vacuum pervaporation. Nonporous diffusion membranes based on a thermally rearranged polymer and its hydrolytically stable prepolymer have been selected as the objects of the research. The main physicochemical parameters of the membranes, such as contact angles, surface tension, membrane density, and the results of sorption tests, are reported. Transport properties of the membranes have been studied for separation the water-n-butanol mixture with the water content in the mixture varied from 10 to 75 wt %. It has been shown that thermal rearrangement of the polymers leads to structure compacting and to more selective penetration of water molecules through the polymer matrix, thereby facilitating effective removal of water impurities from n-butanol.