Decolorization of Post-Consumer Fibers

Abstract

Methods, compositions, single phase aqueous solutions, process mixtures, and kits are provided relating to decolorizing post-consumer fibers, e.g., from carpet pile, using a single-phase aqueous solution. For example, a method of decolorizing post-consumer fibers may include providing the single phase aqueous solution. The single phase aqueous solution may include water, a stable peroxygen composition, and a surfactant composition. The method may include providing the post-consumer fibers comprising a colorant. The method may include contacting the single phase aqueous solution and the post-consumer fibers to form a process mixture under conditions effective to provide a decolorized portion of the post-consumer fibers.

1 . A single-phase aqueous solution for at least partly decolorizing post-consumer fiber, the single-phase aqueous solution comprising:
 water in a weight percent concentration (w/w) of the single-phase aqueous solution of at least about one or more of: 92%;   a stable peroxygen composition; and   a surfactant composition comprising at least one of:
 a polyethylene glycol alkylphenol ether; and 
 a water-soluble polymer comprising repeat units corresponding to monomers of one or more of acrylic acid, maleic acid, vinylpyrrolidone, and vinylimidazole. 
   
     
     
         2 . The single-phase aqueous solution of  claim 1 , the stable peroxygen composition comprising an alkali metal salt of one or more of: peroxide, percarbonate, persulfate, or perborate. 
     
     
         3 . The single-phase aqueous solution of  claim 1 , the stable peroxygen composition being present in an amount effective to provide:
 a peroxide concentration in millimoles per liter (mM) of about one of: 10, 20, 25, 50, 75, 100, 125, 150, 175, 191, 200, 225, 250, 275, 300, 350, 400, 450, 500, 600, 700, 800, 900, or 1000, or a range between any two of the preceding values; or   sodium percarbonate in a weight percent concentration (w/w) with respect to the water of about one of: 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.75%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, or a range between any two of the preceding values.   
     
     
         4 . The single-phase aqueous solution of  claim 1 , comprising the polyethylene glycol alkylphenol ether in a weight percent concentration (w/w) with respect to the water of about one of: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.25%, 0.3%, 0.35, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, or a range between any two of the preceding values. 
     
     
         5 . The single-phase aqueous solution of  claim 1 , the polyethylene glycol alkylphenol ether characterized by an average number of ethylene oxide repeat units of one of about: 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25, or a range between any two of the preceding values. 
     
     
         6 . The single-phase aqueous solution of  claim 1 , an alkyl group of the polyethylene glycol alkylphenol ether being a C 4 -C 16 , branched or unbranched alkyl group; or
 the polyethylene glycol alkylphenol ether being represented by the following formula, wherein n is an average number of repeat units from about 9 to about 14:   
       
         
           
           
               
               
           
         
       
     
     
         7 . The single-phase aqueous solution of  claim 1 , the polyethylene glycol alkylphenol ether comprising one or more of: octoxynol-9, octoxynol-10, octoxynol-11, and octoxynol-12. 
     
     
         8 . The single-phase aqueous solution of  claim 1 , further comprising an amount of polyethylene oxide in a weight percentage compared to the polyethylene glycol alkylphenol ether of one of about: 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, or 20%, or a range between any two of the preceding values. 
     
     
         9 . The single-phase aqueous solution of  claim 1 , comprising the water-soluble polymer in a weight percent concentration (w/w) with respect to the water of about one of: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.25%, 0.3%, 0.35, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, or a range between any two of the preceding values. 
     
     
         10 . The single-phase aqueous solution of  claim 1 , the water-soluble polymer comprising:
 one or more of a homopolymer of acrylic acid and a copolymer of acrylic acid and maleic acid; or   one or more of: vinylpyrrolidone and vinylimidazole.   
     
     
         11 . The single-phase aqueous solution of  claim 1 , further comprising a chelating agent wherein the chelating agent is polydentate; or the chelating agent comprises an aminopolycarboxylic acid or an alkali metal salt thereof; or the chelating agent comprises a disodium salt of ethylene diamine tetraacetic acid; and
 the chelating agent in a weight percent concentration (w/w) with respect to the water of about one of: 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.75%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, or a range between any two of the preceding values.   
     
     
         12 . A process mixture, comprising:
 a post-consumer fiber, the post-consumer fiber comprising a colorant that is one or more of:   a dye; a pigment; and a contaminant; and   a single-phase aqueous solution in contact with the post-consumer fiber, the single phase aqueous solution comprising:
 water in a weight percent concentration (w/w) of the single-phase aqueous solution of at least about 92%; 
 a stable peroxygen composition; and 
 a surfactant composition comprising at least one of:
 a polyethylene glycol alkylphenol ether; and 
 a water-soluble polymer comprising repeat units corresponding to monomers of one or more of acrylic acid, maleic acid, vinylpyrrolidone, and vinylimidazole. 
 
   
     
     
         13 . The process mixture of  claim 12 , the post-consumer fiber comprising one or more of: wool; cotton; acrylic; cellulose; sisal; jute; hemp; bamboo; an acrylic, a nylon; polyethylene terephthalate, polytrimethylene terephthalate; an olefin; blends thereof; copolymers thereof; and recycled fibers thereof; or
 the post-consumer fiber comprising fibers in the form of one or more of: staple fiber and bulk continuous filament; or   the post-consumer fiber being derived from a carpet pile.   
     
     
         14 . The process mixture of  claim 12 , the post-consumer fiber characterized by an arrangement of fibers in the form of one or more of: a woven textile, a nonwoven textile, a tufted pile, a looped pile, a patterned pile, a frieze pile, a textured pile, a multi-level pile, a cut or tip-sheared pile, a cut and loop pile, a random cut pile, a Saxony pile, a plush pile, a shag pile, a needle felt, and a nonwoven portion of fiber. 
     
     
         15 . The process mixture of  claim 12 , comprising the water in a weight ratio to the post-consumer fiber of one or more of about: 6:1, 12:1, 18:1, 24:1, 30:1, 36:1, 42:1, or 48:1, or a range between any two of the preceding ratios. 
     
     
         16 . A method for at least partly decolorizing post-consumer fiber using a single-phase aqueous solution, comprising:
 providing the single phase aqueous solution comprising:
 water; 
 a stable peroxygen composition; and 
 a surfactant composition comprising at least one of:
 a polyethylene glycol alkylphenol ether; and 
 
 a water-soluble polymer comprising repeat units corresponding to monomers of one or more of acrylic acid, maleic acid, vinylpyrrolidone, and vinylimidazole; 
   providing the post-consumer fiber comprising one or more colorants; and   contacting the single phase aqueous solution and the post-consumer fiber to form a process mixture under conditions effective to provide a decolorized portion of the post-consumer fiber.   
     
     
         17 . The method of  claim 16 , the conditions effective to provide the decolorized portion of the post-consumer fiber comprising:
 heating the process mixture at a temperature of about one or more of: 50° C. to 100° C.; 60° C. to 100° C.; 60° C. to 95° C.; 60° C. to 90° C.; 60° C. to 85° C.; 65° C. to 85° C.; 80° C. to 85° C.; and 82° C.; or   one or more of agitating and stirring; or   comprising heating and agitating for a time in hours of one or more of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, 22, 24, 30, 36, 42, or 48, or a range between any two of the preceding values.   
     
     
         18 . The method of  claim 16 , comprising:
 determining an initial colorant level of the post-consumer fiber and the initial colorant level of the post-consumer fiber being characterized by an L initial  value; and   determining a decolorized level of the colorant in the post-consumer fiber, the decolorized level of the colorant in the post-consumer fiber being characterized by an L decolorized  value, L decolorized  being greater than L initial  by one or more of: a value of at least about one of: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 25, 30, 35, or 40; or a percentage at least about one of: 102.5%, 105%, 107.5%, 110%, 112.5%, 115%, 117.5%, 120%, 125%, 130%, 135%, 140%, 145%, or 150%.   
     
     
         19 . The method of  claim 16 , further comprising:
 one or more of separating and recovering at least a portion of the colorant from the process mixture; or   comprising conducting the method via one or more of: batch operation and continuous operation.   
     
     
         20 . A kit for decolorizing post-consumer fiber, comprising:
 a stable peroxygen composition;   a surfactant composition comprising at least one of:
 a polyethylene glycol alkylphenol ether; and 
 a water-soluble polymer comprising repeat units corresponding to monomers of one or more of acrylic acid, maleic acid, vinylpyrrolidone, and vinylimidazole; 
   instructions, the instructions directing a user to:
 provide the stable peroxygen composition and the surfactant composition as a single-phase aqueous solution; and 
 contact the single phase aqueous solution and to a post-consumer fiber comprising 
   a colorant to form a process mixture under conditions effective to provide a decolorized portion of the post-consumer fiber.