Process for continuous extraction of polyamide particles in an essentially vertical extraction column using an aqueous extraction agent, and, extraction column to perform the same

摘要

'' PROCESS FOR CONTINUOUS EXTRACTION OF POLYAMIDE PARTICLES IN AN ESSENTIALLY LINEAR EXTRACTION COLUMN USING A WATERFUL EXTRACTION AGENT, AND, ESSENTIALLY LINEAR EXTRACTION COLUMN TO PERFORM THE SAME "A process is described to continuously extract a polished particle solution recirculation extraction in a vertical extraction column divided into two zones.The polyamide is treated in the first zone with an aqueous solution of SYM -caprolactam with 40 to 95% by weight of SYM -caprolactam as an extraction agent in 100 to 140 ° C, then subsequently treated with water in the second zone Finally, caprolactam can be extracted in a manner known per se The process allows polyamide with a low dimer content to be economically produced.