The present invention relates to a process for forming cellulose fibers or film from dissolved cellulose. The process comprises the steps of: dissolving cellulose in an aqueous coagulation sodium salt solution to provide a cellulose spin dope; extruding the cellulose spin dope into a coagulation bath liquid comprising an aqueous coagulation sodium salt solution to provide cellulose fibers or film; withdrawing a portion of the coagulation bath comprising coagulation sodium salt and sodium hydroxide (NaOH); cooling the withdrawn portion of the coagulation bath to precipitate solid coagulation sodium salt to recover sodium hydroxide (NaOH) substantially free from the coagulation salt; and using at least a portion of the recovered sodium hydroxide (NaOH) in dissolving the cellulose to provide the cellulose spin dope.

The present invention relates to a process for forming cellulose fibers or film from dissolved cellulose. The process comprises the steps of: dissolving cellulose in an aqueous coagulation sodium salt solution to provide a cellulose spin dope; extruding the cellulose spin dope into a coagulation bath liquid comprising an aqueous coagulation sodium salt solution to provide cellulose fibers or film; withdrawing a portion of the coagulation bath comprising coagulation sodium salt and sodium hydroxide (NaOH); cooling the withdrawn portion of the coagulation bath to precipitate solid coagulation sodium salt to recover sodium hydroxide (NaOH) substantially free from the coagulation salt; and using at least a portion of the recovered sodium hydroxide (NaOH) in dissolving the cellulose to provide the cellulose spin dope.

The invention relates to a method for providing an amount of pigment in which, when glycosidic bonds of a polysaccharide structure are cleaved, pigments contained in the polysaccharide structure, in particular pigments comprising color, luminous and/or flame-retardant pigments, are released and the amount of pigment is formed by the pigments released in this manner.

A process (100) for the recovery of solvent (1) from solvent-containing cellulosic particles (2) is shown, the process comprising the steps: a) extracting the solvent (1) from the cellulosic particles (2) by means of a liquid extraction medium (3), thereby obtaining a solvent-enriched extraction medium (5), and b) obtaining the recovered solvent (6) from the solvent-enriched extraction medium (5). In order to improve the efficiency of the process, it is proposed that in step a) the solvent (1) is extracted from the cellulosic particles (2) in a continuous flow extraction reactor (4), wherein the extraction medium (3) continuously flows through the extraction reactor (4) to extract the solvent (1) from the cellulosic particles (2).

A process (100) for the recovery of solvent (1) from solvent-containing cellulosic particles (2) is shown, the process comprising the steps: a) extracting the solvent (1) from the cellulosic particles (2) by means of a liquid extraction medium (3), thereby obtaining a solvent-enriched extraction medium (5), and b) obtaining the recovered solvent (6) from the solvent-enriched extraction medium (5). In order to improve the efficiency of the process, it is proposed that in step a) the solvent (1) is extracted from the cellulosic particles (2) in a continuous flow extraction reactor (4), wherein the extraction medium (3) continuously flows through the extraction reactor (4) to extract the solvent (1) from the cellulosic particles (2).

A recycled mixed textile having cellulosic fibers and synthetic fibers, wherein the synthetic fibers comprise at least two synthetic plastics, a first synthetic plastic of the two synthetic plastics is selectively depleted from the mixed textile and a second synthetic plastic of the two synthetic plastics is partially retained in the mixed textile, and the mixed textile is further processed to comprise the cellulose fibers and the synthetic fibers are the second synthetic plastic.

A recycled mixed textile having cellulosic fibers and synthetic fibers, wherein the synthetic fibers comprise at least two synthetic plastics, a first synthetic plastic of the two synthetic plastics is selectively depleted from the mixed textile and a second synthetic plastic of the two synthetic plastics is partially retained in the mixed textile, and the mixed textile is further processed to comprise the cellulose fibers and the synthetic fibers are the second synthetic plastic.

The present invention concerns a method for the recovery of solvent in a process for preparation of regenerated cellulosic fibers using sodium hydroxide as solvent for cellulose dissolving in the manufacturing of a cellulose spinning dope wherein sodium hydroxide present in the spinning dope is at least partially recovered and recycled as sodium hydroxide from a cellulose fiber regeneration or cellulose coagulation step and wherein said cellulose fiber regeneration or cellulose coagulation step consists of a bath into which cellulose spinning dope is injected. Recovered sodium hydroxide may be directly or indirectly recycled from a cellulose fiber regeneration or cellulose coagulation step to a cellulose dissolving step.

The present invention concerns a method for the recovery of solvent in a process for preparation of regenerated cellulosic fibers using sodium hydroxide as solvent for cellulose dissolving in the manufacturing of a cellulose spinning dope wherein sodium hydroxide present in the spinning dope is at least partially recovered and recycled as sodium hydroxide from a cellulose fiber regeneration or cellulose coagulation step and wherein said cellulose fiber regeneration or cellulose coagulation step consists of a bath into which cellulose spinning dope is injected. Recovered sodium hydroxide may be directly or indirectly recycled from a cellulose fiber regeneration or cellulose coagulation step to a cellulose dissolving step.

The invention discloses a purification method and system of N-methylmorpholine N-oxide (NMMO), and a N-methylmorpholine N-oxide obtained thereof. The invention is used for recovering and purifying NMMO in a lyocell fiber coagulation bath. The method comprises: performing flocculation, microfiltration, ultrafiltration and nanofiltration membrane separation process to the lyocell fiber coagulation bath to remove macromolecular impurities such as suspending substance, heavy metal ions, heavy metal complexes, polysaccharides, etc., and then performing cooling crystallization between ?20? C. and 78? C. to obtain NMMO hydrate crystals. The NMMO hydrate crystals obtained by the method provided in the invention do not contain PG, PG oxidation products, cellulose breakdown products, and NMMO decomposition products, which are present in the coagulation bath. The NMMO hydrate crystals are added with water to prepare a NMMO aqueous solution with a concentration of 19.8%, and the electrical conductivity is about 14.8 ?s/cm.