Acetone Purification and Cycling (Methylamine removal), solvent in the production of PPS (polyphenylene sulfide)

In the production process of PPS polymerization, NMP decomposes at high temperature and produces methylamine and 1,4-butyrolactone. Methylamine will dissolve in solvent acetone will continue to accumulate and increase. When the acetone solvent is recovered by distillation, the methylamine impurity cannot be fully removed, and the acetone will change color after being stored for a long time, which will lead to the PPS products being coloured and even a reduced viscosity during the recycling process.

The ion exchange resin (IER) method is very excellent and efficient for acetone purification. Acetone will pass cation exchange resins first and then the anion exchange resins, more than 95% methylamine will be removed.

After ion exchange resin system purification, it’s weakly alkaline purified acetone, When it is used in the washing process of PPS, the filament breakage during the spinning process is reduced.

The Ion exchange resin, being a highly environment-friendly and reusable polymer separation medium with a service life of 2-4 years, has great advantages compared with other methods, such as hydrochloric acid, activated carbon, etc.