FIELD: chemistry.
SUBSTANCE: invention relates to the technology of organic solvents, specifically to a method of producing 3-methylsulfolane, which is used to extract aromatic compounds from hydrocarbon mixtures in the petrochemical and oil refining industries. Method includes burning sulphur to obtain sulphur dioxide, which is further cooled to a liquid phase and fed for subsequent reaction with isoprene in the medium of a first portion of a solvent, in the presence of a polymerisation inhibitor, while stirring at temperature of 60-80 °C and pressure of up to 1.0 MPa, for 1-2 hours to obtain 3-methylsulfolene. Then obtained solution of 3-methylsulfolene is freed by evaporation from residual sulphur dioxide and excess solvent, then mixed with the second part of the solvent and crystallized while cooling, and the mother solution is decanted. Crystalline 3-methylsulfolene is hydrogenated in the medium of the third part of solvent at 40-60 °C under pressure of up to 1.0 MPa for 1-2 hours in the presence of a catalyst, to obtain solution of 3-methylsulfolane, which is then purged, filtered and distilled under reduced pressure to obtain commercial 3-methylsulfolane. Residues of the solvent obtained in the course of technological operations are sent to a solvent regeneration unit, from where the purified solvent is returned to the storage tank and then at the mixing stage.
EFFECT: disclosed is an efficient method of producing an end product with high output and high purity while reducing solvent wastes.
12 cl, 2 dwg, 1 ex
