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One of the most urgent tasks is the extraction of acid gases, primarily carbon dioxide, from gas streams: flue gases, natural gas, etc. In recent years, in order to implement this process, CO2 absorption is combined with a membrane separation method. For the absorption of gas mixtures at elevated pressures, the most promising is the use of “physical” absorbents because of the ease of their regeneration, since the selective dissolution of acidic components proceeds without chemical reactions. This system is a gas-liquid membrane contactor in which selective mass transfer of components between two phases separated by a membrane takes place. The selectivity of the separation process is determined by the difference in the solubility of gases in the absorption liquid. In order to isolate CO2 from physical absorbents, the membrane used in gas-liquid contactors must have chemical stability, be impermeable to organic media and have high permeability to the released gases. Promising for these tasks may be a natural biodegradable polymer, cellulose. This polymer is one of the most common renewable, inexpensive and biodegradable organic materials and can be considered as an almost inexhaustible source of raw materials with increasing demand for environmentally friendly and biologically compatible products. Cellulose-based membranes are widely used for gas filtration, pervaporation and separation processes [2]. Gas separation membranes for cellulose show high permeabilities for individual gases and high selectivities for a pair of CO2 and CH4, which also makes it promising for use as a membrane material in gas-liquid contactors. The existing limited number of systems of direct cellulose solvents: DMAA / LiCl, NMP / LiCl, DMSO / paraformaldehyde, Nmethylmorpholine-N-oxide (MMO) makes it difficult to create cellulose-based membranes. In recent years, the method of dissolving cellulose in ionic liquids (IL), which is considered more environmentally friendly, has attracted more and more attention. Co-solvents are also added to the IL to reduce time, temperature and dissolution cost. Thus, the aim of this work is to obtain cellulose membranes from a mixture of ionic liquid 1-ethyl-3-methylimidazolium acetate [Emim]Ac with DMSO for gas-liquid contactors.