Abstract: Process for preparing a solution of cellulose in water-containing tertiary amine N-oxides via preparation of a mixture containing cellulose, tertiary amine N-oxides and water and subsequent reduction of the water content of this mixture, whereby in a first step heat is supplied to the mixture which is subjected to a pressure higher than the partial pressure of the water contained in the mixture, and in a second step the mixture is subjected to flash evaporation, whereby water is evaporated under reduced pressure.

Abstract: A process for manufacturing formed objects such as fibers, filaments, yarns, films, membranes in form of flat membranes, hose membranes and hollow fiber membranes and the like, involves pressing cellulose solutions in an amine oxide of a tertiary amine and if necessary water, in particular in N-methylmorpholine-N-oxide and water, through a nozzle and precipitating the solutions in a coagulation bath and washing the formed objects obtained. The coagulation bath liquid and the washing water is processed, if necessary, for recovery of the amine oxide of the tertiary amine. Hydrogen peroxide, peroxyethanoic acid, ozone or chlorine dioxide is added to the coagulation bath and/or the washing water. The substances added can preferably be decomposed catalytically or by enzymes prior to the recovery process of the water and the solvent.