Recovering method of by-product sodium chloride in polyphenylene sulfide production

The invention discloses a recovering method of a by-product sodium chloride in polyphenylene sulfide production. The method comprises the steps that: (1) impurities are removed by absorption, wherein a water solution containing sodium chloride is added into a collection tank and is stirred and mixed, a temperature is controlled at 55-65 DEG C, active carbon is added, the mixture is well mixed by stirring, and absorption is carried out for 25-35min; (2) solid-liquid separation is carried out, wherein the mixed liquid obtained in the step (1) is filtered, and active carbon and sodium chloride aqueous solution are obtained by separation; and (3) concentration and crystallization are carried out, wherein the sodium chloride aqueous solution obtained in the step (2) is injected into a multi-effect distillation system for concentration, solid-liquid separation is carried out after sodium chloride is precipitated, and sodium chloride crystals are obtained. In the above method, the active carbon used for absorption can be recovered and repeatedly used, such that resource is not wasted. Multi-effect distillation is adopted, such that energy consumption can be greatly reduced. The appearance and content of the recovered sodium chloride satisfy industrial sodium chloride standards, and provide a certain economic benefits. Further, adverse influences of sodium chloride to the environment can be avoided.