US 2011 0110817A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2011/0110817 A1 Lupo et al. (43) Pub. Date: May 12, 2011 (54) RARE EARTH REMOVAL OF COLORANTS Publication Classification (51) Int. Cl. (75) Inventors: Joseph A. Lupo, Henderson, NV A6IL 2/12 (2006.01) (US); Joseph R. Pascoe, Las Vegas, COIF 1700 (2006.01) NV (US) A6IL 2/10 (2006.01) A6IL 2/08 (2006.01) (73) Assignee: MOLYCORP MINERALS, LLC, A6IL 2/6 (2006.01) Greenwood Village, CO (US) C09K 3/00 (2006.01) C09B 62/00 (2006.01) C09B 67/44 (2006.01) (21) Appl. No.: 12/942,847 C09C I/62 (2006.01) CSK 3/08 (2006.01) (22) Filed: Nov. 9, 2010 (52) U.S. Cl. ............... 422/21: 423/263; 422/24; 422/22: 422/28: 422/292; 252/182.33; 8/543; 8/618: Related U.S. Application Data 106/403; 524/440 (60) Provisional application No. 61/259,314, filed on Nov. (57) ABSTRACT 9, 2009, provisional application No. 61/386,347, filed The present disclosure is directed to a method and system for on Sep. 24, 2010, provisional application No. 61/386, contacting a colorant-contaminated aqueous Solution with a 365, filed on Sep. 24, 2010, provisional application rare earth-containing composition to form a treated Solution No. 61/386,394, filed on Sep. 24, 2010. substantially depleted of the colorant. Patent Application Publication May 12, 2011 Sheet 1 of 3 US 2011/O110817 A1 COLORANT-CONTAINING AGUEOUS SOLUTION / Y2Y120 V OPTIONAL PRE-TREATMENT / N-me O O O le1 104 112 RARE EARTH-CONTAINING CONTACT OF SOLUTION WITH RARE COMPOSITION EARTH-CONTAINING COMPOSITION - - w 132 - - - - - - - ( REGENERATION OPTIONAL POST-TREATMENT // N / V / t New aaaaaaaaaaaaaa- aaaaaaaaa- ax- e1 108 - - -/ wn) w was w aw in 128 CONTAMINATE- /SEPARATION OF CONTAMINATE-Y// CONTAININGCOMPOSITION RAREEARTH V CONTAININGCOMPOSITION RARE EARTH / - - - - - - N- - - - -1 TREATED SOLUTION F.G. 1 Patent Application Publication May 12, 2011 Sheet 2 of 3 US 2011/O110817 A1 S S S& Patent Application Publication May 12, 2011 Sheet 3 of 3 US 2011/O110817 A1 Fig. 5B Fig. 7B US 2011/011 0817 A1 May 12, 2011 RARE EARTHREMOVAL OF COLORANTS 0009. Another option is to pass the colorant-containing aqueous stream through an expensive ultrafilter, nanofilter, CROSS REFERENCE TO RELATED and/or reverse osmosis membrane system to separate the APPLICATION colorant from the water. Typically, the separation is based on molecular size. 0001. The present application claims the benefits of U.S. 0010 Yet another option is to use physical-chemical colo Provisional Application Ser. No. 61/259,314, filed Nov. 9, rant removal methods. Coagulant agents, such as ferric salts 2009, entitled “Removal of Water Soluble Organic Dyes and aluminum polychloride, form flocks with the colorants, Using Cerium Oxide': 61/386,347, filed Sep. 24, 2010, which are then separated by filtration or sedimentation. entitled “Removal of a Dye From An Aqueous System Using 0011 Still yet another option is to biologically degrade the Rare Earths': 61/386,365, filed Sep. 24, 2010, entitled colorant with a microbe under aerobic and/or anaerobic con “Removal of a Colorant From An Aqueous System Using ditions. Typically the microbes are bacteria or fungi. Rare Earths”; and 61/386,394, filed Sep. 24, 2010, entitled 0012 Another option is to remove the colorant by an “Removal of a Pigment From An Aqueous System Using adsorption process. Colorants, such as dyes have high affini Rare Earths, each of which is incorporated herein by this ties for adsorbent materials. reference in its entirety. 0013 Although many techniques have been used to remove colorants, there is no single and economically attrac FIELD tive treatment that can effectively remove and/or decolorize 0002 The invention relates generally to removal of colo dyes and their decomposition products. rants and particularly to rare earth removal of colorants from SUMMARY aqueous Streams. 0014. These and other needs are addressed by the various BACKGROUND embodiments and configurations of the present invention. The invention relates generally to the removal of a selected 0003 Colorants are used in a wide variety of applications. component of a colorant composition from a contaminated Colorants, for example, are used in food products, textiles, aqueous Solution. personal care products, paints, and a host of other products. 0015. In an embodiment, a treatment method is provided Colorants typically comprise a dye or a pigment. that contacts a colorant-containing aqueous Solution with a 0004 The scale and growth of the dye industry is inextri rare earth-containing composition to form a treated solution cably linked to that of the textile industry. World textile pro substantially depleted of the colorant. duction has grown steadily to an estimated 35 million tons in 0016. In an embodiment, a treatment system is provided 1990, and the estimated production of dyes in 2009 was that includes: around 120 million tons. 0017 an inlet for a colorant-containing aqueous solution; 0005 With the increased demand for textile products, the 0018 a rare earth-containing composition in a colorant textile industry and its wastewaters have been increasing pro removal Zone; and portionately, making it one of the main sources of water 0019 an outlet for a treated aqueous solution substantially pollution worldwide. The release of colorant-containing depleted of the colorant. effluents into the environment is undesirable, not only 0020. In an embodiment, the method and/or system pro because of their color but also because many colorants and duce a contaminated rare earth-containing composition their breakdown products are toxic and/or mutagenic to life. including the rare earth and the colorant sorbed on the rare Many of the colorants are chemically stable and without earth. In other embodiments, the colorant is degraded or adequate treatment they can remain in the environment for an decomposed by the rare earth, Such as by destruction of a extended period of time. Furthermore, many colorants in chromophore. particular pigments comprise heavy metals. In addition to 0021. In an embodiment, a regeneration method is pro environmental pollution, the textile industry contributes to vided that includes the steps: water shortage by consuming large amounts of potable water. 0022 (a) providing a contaminated rare earth-containing In many countries where potable water is scarce, this large composition comprising a rare earth and a colorant Sorbed on water consumption has become intolerable and wastewater the rare earth and recycling has been recommended to decrease the water 0023 (b) sterilizing the contaminated rare earth-contain requirements. ing composition to remove the colorant. 0006. As a consequence of these issues, increasingly strin 0024. The embodiments can provide a number of advan gent government air and water pollution control regulations tages depending on the particular configuration. For example, are restricting colorant use. Various organizations and/or in many applications rare earth-containing compositions can agencies, as for example, the American Organization of Ana economically and effectively decolorize or remove colorants. lytical Chemists, the World Health Organization, and the US Accordingly, the embodiments can overcome the environ Environmental Protection Agency have addressed the issue of mental problems associated with colorant discharge and air and water pollution arising from colorant usage. enable wastewater recycling to decrease water requirements 0007. However, removal of colorants from aqueous of the textile industry. The rare earth-containing composition streams can be difficult. can treat colorant contaminated aqueous solutions to con 0008. One option to remove colorants from water streams tamination levels in compliance with the increasingly strin is to add expensive chemicals that destroy or react with the gent air and water pollution control regulations by private and colorant. Chemical oxidation uses a suitable oxidizing agent, governmental organizations, such as the American Organiza Such as OZone, hydrogen peroxide, or permanganate to tion of Analytical Chemists, the World Health Organization, change the chemical composition of a colorant, such as a dye. and the US Environmental Protection Agency. US 2011/011 0817 A1 May 12, 2011 0025. These and other advantages will be apparent from taminant may be rendered non-toxic by converting the con the disclosure of the invention(s) contained herein. taminant into a non-toxic form or species. 0026. The term “a” or “an entity refers to one or more of 0037. A “dye' is a colorant, usually transparent, which is that entity. As such, the terms “a” (or “an”), “one or more' and soluble in an application medium. Dyes are classified accord “at least one' can be used interchangeably herein. It is also to ing to chemical structure, usage, or application method. They be noted that the terms “comprising”, “including, and “hav are composed of groups of atoms responsible for the dye ing can be used interchangeably. color, called chromophores, and intensity of the dye color, 0027. The terms “at least one”, “one or more', and “and/ or are open-ended expressions that are both conjunctive and called auxchromes. The chemical structure classification of disjunctive in operation. For example, each of the expressions dyes, for example, uses terms such as azo dyes (e.g., “at least one of A, B and C', 'at least one of A, B, or C, “one monoazo, disazo, trisazo, polyazo, hydroxyazo, carboxyazo, or more of A, B, and C. “one or more of A, B, or C and “A, carbocyclic azo, heterocyclic