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.

The present invention describes a method of dissolving cellulose, said method comprising: dissolving cellulose in an alkali solution: filtering the dissolved cellulose, thereby forming a filtered dissolved cellulose solution and a filter reject; mixing said filter reject having a first viscosity value with a dissolution liquid having a second viscosity value, wherein the second viscosity value is lower than the first viscosity value, to provide a diluted reject stream having a third viscosity value being lower than the first viscosity value of the filter reject; andseparating inhomogeneities from the diluted reject stream.

A fiber manufacturing method includes the following steps of: dissolving a polymer in a solvent to obtain a polymer solution; spraying the polymer solution into a liquid heated to a boiling point of the solvent or higher, and evaporating the solvent to precipitate a fibrous polymer in a sealed precipitation tank, the liquid being immiscible with the polymer and the solvent; conveying the precipitated fibrous polymer in a liquid from the precipitation tank; water-rinsing the fibrous polymer conveyed in the liquid in the conveying step in a sealed water-rinsing tank; conveying the water-rinsed fibrous polymer in a liquid from the water-rinsing tank; and cooling and condensing solvent gas that is generated in the spraying step and the water-rinsing step.

A fiber manufacturing method includes the following steps of: dissolving a polymer in a solvent to obtain a polymer solution; spraying the polymer solution into a liquid heated to a boiling point of the solvent or higher, and evaporating the solvent to precipitate a fibrous polymer in a sealed precipitation tank, the liquid being immiscible with the polymer and the solvent; conveying the precipitated fibrous polymer in a liquid from the precipitation tank; water-rinsing the fibrous polymer conveyed in the liquid in the conveying step in a sealed water-rinsing tank; conveying the water-rinsed fibrous polymer in a liquid from the water-rinsing tank; and cooling and condensing solvent gas that is generated in the spraying step and the water-rinsing step.

A spunbond method for producing non-woven fabric of natural cellulose with flame-retarding feature comprises following steps. Blend pulp and solvent of N-methylmorpholine N-oxide (NMMO) to form slurry. Evaporate water content from slurry by a Thin Film Evaporator to form dope. Extrude the dope off spin nozzles to form filament strand via spunbond method. Coagulating regenerate, water rinse, hydro-entangled needle-punch and dry the filament strand to form normal natural cellulose nonwoven, which is soaking rolled by flame retardant of N-hydroxymethyl-3-(dimethoxy-phosphate acyl) propyl amide, then orderly bake, alkaline clean, water rinse, dry and wind-up to convert it into modified natural cellulose nonwoven fabrics of long-acting flame retarding feature in coil manner. Because of cross-linking reaction between foregoing flame retardant and natural cellulose nonwoven, the flame-retarding capability thereof meet requirements of testing standards in American ASTM D6413-1999 and ASTM D2863-1995. Moreover, the wastes thereof meet environmental protection requirements.

A spunbond method for producing non-woven fabric of natural cellulose with flame-retarding feature comprises following steps. Blend pulp and solvent of N-methylmorpholine N-oxide (NMMO) to form slurry. Evaporate water content from slurry by a Thin Film Evaporator to form dope. Extrude the dope off spin nozzles to form filament strand via spunbond method. Coagulating regenerate, water rinse, hydro-entangled needle-punch and dry the filament strand to form normal natural cellulose nonwoven, which is soaking rolled by flame retardant of N-hydroxymethyl-3-(dimethoxy-phosphate acyl) propyl amide, then orderly bake, alkaline clean, water rinse, dry and wind-up to convert it into modified natural cellulose nonwoven fabrics of long-acting flame retarding feature in coil manner. Because of cross-linking reaction between foregoing flame retardant and natural cellulose nonwoven, the flame-retarding capability thereof meet requirements of testing standards in American ASTM D6413-1999 and ASTM D2863-1995. Moreover, the wastes thereof meet environmental protection requirements.

A spunbond method for producing non-woven fabric with deodorant feature from bamboo cellulose comprises following process steps. Prepare bamboo pulp mixture by blending bamboo pulp and coffee residue in proper mixing ratio. Put N-methylmorpholine N-oxide (NMMO) as solvent and 1, 3-phenylene-bis 2-oxazoline (BOX) as stabilizer into prepared bamboo pulp mixture to form dope. Via spunbond method, orderly perform extruding, spinning, quenching and pre-drawing process to convert the dope into bamboo filaments of fibrous strand. Orderly process coagulation, regeneration and post-draw to the bamboo filaments of fibrous strand to transform them into uniform fine bamboo cellulose filaments. Bond and lay these bamboo filaments of fibrous strand on a belt collector to form a webbed nonwoven. After post treatments of water rinsing, hydro-entangled needle punching and drying have been orderly applied, then a resultant nonwoven fabric in continuous filament of bamboo cellulose with deodorant feature is produced from the webbed nonwoven.

The present invention provides a production method for purified polysaccharide fibers in which carbon disulfide emission is suppressed while efficiently producing purified polysaccharide fibers having excellent strength, purified polysaccharide fibers produced by using the production method, a fiber-rubber complex using the purified polysaccharide fibers, and a tire having excellent tire characteristics using the fiber-rubber complex. The production method for purified polysaccharide fibers of the present invention is a production method for purified polysaccharide fibers of wet-spinning or dry-wet-spinning polysaccharide by bringing a polysaccharide solution obtained by dissolving a polysaccharide raw material in a liquid including an ionic liquid into contact with a solidification liquid including an ionic liquid, in which a concentration of the ionic liquid in the solidification liquid is 0.4% by weight to 50% by weight and the anionic moieties of the ionic liquid in the polysaccharide solution and the ionic liquid in the solidification liquid have one or more types selected from the group consisting of a phosphinate ion, a phosphate ion, and a phosphonate ion.

The present invention provides a production method for purified polysaccharide fibers in which carbon disulfide emission is suppressed while efficiently producing purified polysaccharide fibers having excellent strength, purified polysaccharide fibers produced by using the production method, a fiber-rubber complex using the purified polysaccharide fibers, and a tire having excellent tire characteristics using the fiber-rubber complex. The production method for purified polysaccharide fibers of the present invention is a production method for purified polysaccharide fibers of wet-spinning or dry-wet-spinning polysaccharide by bringing a polysaccharide solution obtained by dissolving a polysaccharide raw material in a liquid including an ionic liquid into contact with a solidification liquid including an ionic liquid, in which a concentration of the ionic liquid in the solidification liquid is 0.4% by weight to 50% by weight and the anionic moieties of the ionic liquid in the polysaccharide solution and the ionic liquid in the solidification liquid have one or more types selected from the group consisting of a phosphinate ion, a phosphate ion, and a phosphonate ion.

According to an example aspect of the present invention, there is provided a manmade cellulosic textile fibre having a linear density of 0.8-1.8 dtex, a tenacity of 2.0-2.9 cN/dtex, and an initial modulus of 50-120 cN/dtex. The cellulosic textile fibre comprises a cellulose-based material, wherein at least 50 wt-% of the raw material of the textile fibre is cellulose-containing waste, and at least 50 wt-% of the cellulose-containing waste is textile waste.