METHOD OF PURIFICATION OF THE RETURN SOLVENT Russian patent published in 2018 - IPC C08C2/06 C08L21/00 

FIELD: technological processes.

SUBSTANCE: invention refers to the production of synthetic rubbers that are obtained by means of solution polymerization, in particular to the regeneration of the return solvent from the rubber separation step. Method includes rectification of the return solvent on the column, cooling of vapors in the dephlegmator, collecting distillate in the vessel, feeding the reflux with the alkaline agent into the rectification column, pumping out heavy hydrocarbons from the bottom of the column. In this case, the return of 10–90 % of the bottom product which contains the unspent alkaline agent that has the reaction of the aqueous extracting medium with pH 10–12, to the rectification column into the middle part of it above the feed stream.

EFFECT: invention allows to purify the recycled solvent during the production of synthetic rubber from halogen-containing impurities, to maintain the alkaline environment in it in order to avoid corrosion of the equipment, to increase the safety of production of solution polymers.

1 cl, 1 dwg, 5 tbl, 1 ex