Abstract

Disclosed is a method for comprehensive recycling of a by-product slurry during polyphenylene sulfide (PPS) production. Na2CO3 is added to the slurry, and then a solvent NMP is recovered by distillation and drying, then an acid solution is used for dissolving and leaching the resulting dry waste salt, the leaching liquor is subjected to pH adjustment and then filtered, with the insoluble components being removed, the liquid phase is subjected to adsorption and purification and evaporation concentration to separate out NaCl, then Na2CO3 is added to the solution with NaCl separated out for precipitation to obtain Li2CO3, the mother liquor with lithium precipitated is subjected to pH adjustment and then mixed with the solution obtained after adsorption and purification, and a closed circulation of the process is achieved. The method can be used in the comprehensive recycling of the by-product slurry during PPS production, the recovered NaCl can be directly used for caustic soda preparation by ionic membrane electrolysis, and Li2CO3 can directly serve as an industrial product or can be further converted into LiCl to serve as a PPS production auxiliary for recycling.

IPC Classes  ?

• C08G 75/0277 - Post-polymerisation treatment
• C08G 75/0281 - Recovery or purification
• C08G 75/0254 - Preparatory processes using metal sulfides
• C08G 75/0213 - Polyarylenethioethers derived from monomers containing one aromatic ring containing elements other than carbon, hydrogen or sulfur
• C01D 15/08 - CarbonatesBicarbonates
• C01D 3/14 - Purification
• C07D 207/267 - 2-Pyrrolidones with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to other ring carbon atoms with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atom