ハロゲン酸イオン交換を用いる繊維から硫黄を除去する方法

摘要

The present invention concerns methods for removing sulfur from a fiber made from a polymer comprising imidazole groups, said method comprising: a) contacting never-dried sulfate anion-containing polymeric-fiber with an halide-containing acid to displace at least a portion of the sulfate ions with halide anions; and b) rinsing the fiber to remove the displaced sulfate ions.