Process for purifying aqueous solutions of N-methylmorpholine-N-oxide

To clean aqueous solutions of N-methylmorpholine-N-oxide, especially spinning bath solutions, the solutions according to the invention are brought into contact with adsorbents and then submitted to filtration. Aluminium oxide, silicon oxide or charcoal are used preferentially as adsorbents. A reasonable grain size of adsorbents amounts to less than 0,15 mm. The presence of adsorbents make easy the filtration of substances which cause turbidity, and besides discolouration results in elimination of metallic salts. To clean aqueous solutions of N-methylmorpholine-N-oxide, especially spinning bath solutions, the solutions according to the invention are brought into contact with adsorbents and then submitted to filtration. Aluminium oxide, silicon oxide or charcoal are used preferentially as adsorbents. A reasonable grain size of adsorbents amounts to less than 0,15 mm. The presence of adsorbents make easy the filtration of substances which cause turbidity, and besides discolouration results in elimination of metallic salts. Za čiščenje vodnih N-metilmorfolin-N-oksidnih raztopin, zlasti raztopin predilnih kopeli, spravimo raztopine v smislu izuma v kontakt z adsorpcijskimi sredstvi in zatem podvržemo filtraciji. Kot adsorpcijsko sredstvo uporabimo prednostno aluminijev oksid, silicijev oksid ali oglje. Adsorpcijska sredstva imajo smiselno velikost zrn manjšo od 0,15 mm. Prisotnost adsorpcijskih sredstev olajša filtracijo snovi, ki povzročajo motnost, in učinkuje poleg razbarvanja tudi pri odstranjevanju kovinskih soli.ŕ