# US 10,370,778 B2 · Recycling of man-made cellulosic fibers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,370,778 B2 - Document ID: US10370778B2 - Status: Granted - Kind: B2 - Application number: 15/545,899 - Filed: 2016-02-03 - Published: 2018-01-04 - Granted: 2019-08-06 - Earliest claimed: 2015-02-06 - Assignees: Lenzing Aktiengesellschaft - Applicants: Lenzing AG - Inventors: Christian Sperger - Web page: https://patentgrep.com/patent/US10370778B2 ## CPC - D01F 13/02: of cellulose, cellulose derivatives or proteins {(recovery of sodium sulfate from coagulation baths C01D5/006)} - C08B 1/08: Alkali cellulose - C08B 9/00: Cellulose xanthate; Viscose {(formation of films C08J5/18; formation of fibres D01F; rendering cellulose suitable for esterification C08B1/02)} - C08B 16/00: Regeneration of cellulose - C08J 11/04: of polymers - D01F 2/08: Composition of the spinning solution or the bath - C08J 2301/02: Cellulose; Modified cellulose - Y02P 70/62: related technologies for production or treatment of textile or flexible materials or products thereof, including footwear - D01F: CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS - C08B: POLYSACCHARIDES; DERIVATIVES THEREOF (polysaccharides containing less than six saccharide radicals attached to each other by glycosidic linkages C07H; fermentation or enzyme-using processes C12P19/00; sugar industry C13; production of cellulose D21) - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A process for producing a man-made cellulosic molded body using a man-made cellulosic raw material, including the steps of forming a cellulose solution by dissolution of cellulosic raw material, the extrusion of the cellulose solution obtained to form a molded body, and coagulation and regeneration of the cellulose to obtain the man-made cellulosic molded body, wherein the man-made cellulosic raw material is mixed with a second cellulosic raw material prior to forming the cellulose solution. ## Claims ### Claim 1 A process for producing a man-made cellulosic molded body using a reclaimed man-made cellulosic raw material and a virgin cellulosic raw material, comprising the steps of: a) steeping the reclaimed man-made cellulosic raw material in caustic soda in an alkalization stage and subsequently squeezing to obtain alkali cellulose, b) xanthation of the alkali cellulose and subsequently dissolution of cellulose xanthate to obtain a cellulose xanthate solution, c) extruding the cellulose xanthate solution, d) coagulating and regenerating cellulose to obtain the man-made cellulosic molded body, wherein before step b) in an additional combination step the alkali cellulose made of the reclaimed man-made cellulosic raw material is combined with alkali cellulose made of the virgin cellulosic raw material in a second alkalization line and wherein the combined alkali celluloses are further processed jointly in the xanthation step b). ### Claim 2 (depends on 1) The process according to claim 1, wherein the reclaimed man-made cellulosic raw material was obtained from pre- and/or post-consumer waste containing man-made cellulosic fibers produced by the viscose-, modal or lyocell process. ### Claim 3 (depends on 2) The process according to claim 2, wherein the pre- and/or post-consumer waste further comprises non-cellulosic fibers and wherein these non-cellulosic fibers are quantitatively separated from the reclaimed man-made cellulosic raw material prior to step a). ### Claim 4 (depends on 1) The process according to claim 1, further comprising a metal removing stage which comprises an acidic washing treatment and/or a treatment with a complexing agent. ### Claim 5 (depends on 4) The process according to claim 4, wherein the acidic washing treatment and the treatment with a complexing agent in the metal removing stage are combined in one step by adding a complexing agent to the acidic washing treatment. ### Claim 6 (depends on 1) The process according to claim 1, wherein the molded body is a staple fiber, filament fiber, sponge or foil of the Viscose or Modal type. ### Claim 7 (depends on 1) The process according to claim 1, wherein the difference between limiting viscosity numbers of the alkali cellulose of the reclaimed man-made cellulosic raw material and the alkali cellulose of virgin cellulosic raw material is equal to or lower than 30 ml/g. ### Claim 8 (depends on 1) The process according to claim 1, wherein the reclaimed man-made cellulosic raw material is a staple fiber, filament fiber, sponge or foil of the Viscose or Modal type or of the Lyocell type. ### Claim 9 (depends on 1) The process according to claim 1, wherein in the additional combination step a share of the reclaimed man-made cellulosic raw material is from 10 to 90%. ### Claim 10 (depends on 7) The process according to claim 7, wherein the difference between the limiting viscosity numbers of the alkali cellulose of the reclaimed man-made cellulosic raw material and the alkali cellulose of virgin cellulosic raw material is equal to or lower than 10 ml/g. ### Claim 11 (depends on 9) The process according to claim 9, wherein the share of the reclaimed man-made cellulosic raw material is from 20 to 80%. ### Claim 12 (depends on 11) The process according to claim 11, wherein the share of the reclaimed man-made cellulosic raw material is from 40 to 60%. ### Claim 13 (depends on 1) The process according to claim 1, further comprising mechanically shredding the reclaimed man-made cellulosic raw material. ### Claim 14 (depends on 1) The process according to claim 1, further comprising pre-treating the reclaimed man-made cellulosic raw material in a metal removing stage, a decoloring stage and/or cross linker removing stage prior to the alkalization step. ### Claim 15 (depends on 1) The process according to claim 1, further comprising pre-aging the alkali cellulose.