The separation of aqueous-alcohol solutions and dehydration of N,N-dimethylacetamide (DMAA), which form azeotropes, is important for the production of polymer materials, anhydrous alcohols for medicine, fuel, food and other industries. Currently, there are about one hundred pervaporation modules in operation around the world, most of which are designed for the dehydration of various solvents, such as ethanol, isopropanol, etc. It is known that polyamide and polyimide films, due to their high thermal stability, good mechanical strength, and high resistance to organic solvents, are considered promising membrane materials. We synthesized (co)polyamide by low-temperature polycondensation of terephthalic acid chloride with 4,4'-diaminodiphenyloxide and 3 ,5-diaminobenzoic acid in N-methyl-2-pyrrolidone (N-MP). The transport characteristics of membranes cast from this (co)polyamide (SPA) were studied. It was shown that after soaking the samples in water, the weight of the film decreased more than after soaking in isopropanol. This may be due to the different polarity of the molecules of the solvents used. The statement, taking into account the washed out impurities from the polymer, provides the true value of sorption was verified. The separation of a water-isopropanol mixture in the concentration range of 0-100 wt. % water at different temperatures was studied using the pervaporation method. It was shown that over the entire range of concentrations studied, the permeate is enriched with water. Separation coefficients for SPA membranes are comparable with those for PIM and TFC membranes. The temperature dependence of sorption, permeability and selectivity of aqueous solutions of DMAA (5:1) was studied for SPA films. It has been shown that the sorption of the solution by the polymer did not change within 20-50оС, then decreases, and the permeability of the separated mixture increased by 2-3 times, and the permeate contained only water. Thus, SPA (co)polyamide can be considered as a basis for obtaining selective membranes during the dehydration of alcohols and organic solvents.
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