Abstract: The invention is concerned with a process for the selective separation of morpholine from an aqueous solution containing morpholine, N-methylmorpholine and N-methylmorpholine-N-oxide, characterized by the following steps:(A) passing said aqueous solution over a cation exchanger capable of adsorbing morpholine in such an amount until it cannot be charged substantially with morpholine any more and an eluate substantially free from morpholine but containing N-methyhnorpholine and N-methylmorpholine-N-oxide is obtained, and(B) regenerating the cation exchanger charged with morpholine and reusing it in step (A).

Abstract: The invention is concerned with a process for the production of a solution of N-methylmorpholine-N-oxide in water, characterized by the following steps:(a) providing an aqueous solution containing N-methylmorpholine and morpholine and exhibiting a pH value of from 6.0 to 9.0, thereafter(b) treating said aqueous solution with a peroxidic oxidant to oxidize N-methylmorpholine to N-methylmorpholine-N-oxide.

Abstract: The invention is concerned with a process for the production of an aqueous amine-oxide solution used in the amine-oxide process for the production of a mouldable cellulose solution, wherein aqueous, amine-oxide containing solutions produced in said amine-oxide process particularly as precipitation baths are purified and concentrated, characterized in that a microbiocide agent is added to said aqueous, amine-oxide containing solutions before, during or after purification.

Abstract: The invention is concerned with a process for the purification of an aqueous solution of a tertiary amine-oxide containing impurities partially present in a dissolved and partially in a non-dissolved, colloidal state, and is characterized by a combination of the steps of(A) removing from the aqueous solution substantially all of said impurities present in a non-dissolved, colloidal state and(B) contacting said aqueous solution obtained in step (A) with an ion exchanger.

Abstract: The invention is concerned with a process for the production of cellulose moulded bodies. In this process, cellulose is first dissolved in an aqueous solution of a tertiary amine-oxide, in particular N-methylmorpholine-N-oxide (NMMO), to produce a mouldable cellulose solution. Second, the cellulose solution is molded and conducted into an aqueous precipitation bath, wherein the cellulose is precipitated, which produces a moulded body and a spent precipitation bath. Next, the spent precipitation bath is regenerated. This regenerated aqueous amine-oxide solution is re-used to dissolve cellulose, thereby repeating the process. In the above process, the repeated aqueous amine-oxide solution has a pH within certain defined limits.