摘要 |
Purification of a virtually anhydrous organic liquid to decrease its content of alkali metal, alkaline earth metal and other metal cations comprises contacting the liquid with one or more cation exchange resins in acidic or ammonium form. At least one of the resins is a sulphonic resin containing SO3H or SO3NH4 groups and based upon a polystyrene-divinylbenzene copolymer having 50-60 wt.% divinylbenzene content (without taking the sulphonic groups into account). The liquid may not be dimethylsulphoxide (DMSO) alone. |