Method of reducing color in alkanolamine compositions and compositions produced thereby

Abstract

A method of reducing color in an alkanolamine is described. The method includes contacting the alkanolamine with a color-reducing amount of a borane complex effective to provide a color-reduced alkanolamine composition having a Platinum-Cobalt Color Value, according to Test Method ASTM D1209, of less than 50.

Claims

1. A method of reducing color in an alkanolamine, the method comprising the step of: contacting the alkanolamine with a color-reducing amount of a borane complex effective to provide an alkanolamine composition having a Platinum-Cobalt Color Value, Test Method ASTM D1209, of less than 50; wherein the borane complex is of the formula
L.BH.sub.3 wherein L is ammonia or a C.sub.1-24 organic amine, an organic phosphine substituted with three C.sub.1-12 hydrocarbyl groups, a C.sub.3-18 heterocycle, or a C.sub.2-20 thioether; or the borane complex is of the formula
H.sub.3N.BR.sub.aH.sub.3-a wherein a is 1 or 2, and each R is independently the same or different, and is a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein two R form a ring with the boron atom.

2. The method of claim 1, wherein the alkanolamine is a mono(C.sub.1-10 alkanol)amine, a di(C.sub.1-10 alkanol)amine, a tri(C.sub.1-10 alkanol)amine, an N(C.sub.1-10 alkyl) di(C.sub.2-4 alkanol)amine, an N,N-di(C.sub.1-10 alkyl) (C.sub.2-4 alkanol)amine, an N(C.sub.1-10 alkanol)pyrrolidine, N(C.sub.1-10 alkanol)imidazolidine, an N(C.sub.1-10 alkanol)piperidine, an N(C.sub.1-10 alkanol)piperazine or a combination comprising at least one of the foregoing.

3. The method of claim 1, wherein the alkanolamine is a tri(C.sub.1-10 alkanol)amine.

4. The method of claim 1, wherein L is ammonia or a C.sub.1-24 amine of the formula ##STR00016## wherein each R.sup.1 is independently hydrogen or a C.sub.1-8 hydrocarbyl group, optionally wherein any two R.sup.1 form a ring with the nitrogen atom, and provided that not all R.sup.1 are hydrogen, or hydrogen, a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-18 aromatic group, or a C.sub.3-15 heteroaromatic group, or any two R.sup.1 together form a C.sub.2-6 ring with the nitrogen atom that can optionally have 1 or 2 heteroatoms as ring members, and provided that not all R.sup.1 are hydrogen.

5. The method of claim 4, wherein L is an organic phosphine of the formula ##STR00017## wherein each R.sup.3 is independently a C.sub.1-12 hydrocarbyl group.

6. The method of claim 1, wherein L is a C.sub.2-20 thioether of the formula ##STR00018## wherein each R.sup.2 is independently a C.sub.1-10 hydrocarbyl group.

7. The method of claim 1, wherein L is a C.sub.3-18 aliphatic heterocycle with 3 to 12 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, phosphorus, silicon, or sulfur.

8. The method of claim 1, wherein L is a C.sub.3-18 aromatic heterocycle with 1 to 3 rings and 5 to 14 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur.

9. The method of claim 1, wherein L is ammonia, dimethylamine, trimethylamine, triethylamine, tetrahydrofuran, morpholine, or pyridine.

10. The method of claim 1, wherein the contacting is with 1 to 5,000 ppm by weight of the borane complex, based on the weight of the alkanolamine.

11. The method of claim 1, wherein the borane complex is dissolved in a solvent before the contacting.

12. The method of claim 10, wherein the borane complex has a concentration in the solvent is 1 to 30 wt %, based on total weight of the components.

13. The method of claim 12, further comprising mixing the alkanolamine with the borane complex during or after the contacting.

14. The method of claim 13, wherein the contacting is at a temperature of 20 C. to 250 C. and for 10 minutes to 50 hours.

Description

DETAILED DESCRIPTION

(1) As described above, unacceptable levels of color and color bodies can be found in finished, purified alkanolamines Additionally, color bodies can form as contaminants in finished, pure alkanolamines over a period of time, for example during storage. The inventors hereof have discovered methods of reducing color in alkanolamines, or maintaining reduced color in alkanolamines. In a key feature of the methods, the alkanolamines are contacted with a borane complex to provide color-reduced alkanolamine compositions. Advantageously, after contacting, these alkanolamine compositions are colorless or near colorless to the human eye. In general, the compositions have a Platinum-Cobalt Color Value of less than 50, less than 30, more preferably 0 to 20, as determined according to Test Method ASTM D1209. In an especially advantageous feature, the low color can be maintained over months or years. Thus, in compositions treated to reduce color, or already having reduced color, the method can be used to maintain the low color over time. In another advantageous feature, the method is fast, and does not required expensive or time-consuming equipment. The reduced-color compositions can be directly packaged or transported.

(2) The method is effective with a wide variety of alkanolamines, which includes linear, branched or cyclic compounds having at least one primary, secondary, or tertiary amino group and at least one alkanol group. Such alkanolamines include a mono(C.sub.1-10 alkanol)amine, a di(C.sub.1-10 alkanol)amine, a tri(C.sub.1-10 alkanol)amine, an N(C.sub.1-10 alkyl) mono(C.sub.2-4 alkanol)amine, an N(C.sub.1-10 alkyl) di(C.sub.2-4 alkanol)amine, an N,N-di(C.sub.1-10 alkyl) (C.sub.2-4 alkanol)amine, an N(C.sub.1-10 alkanol)pyrrolidine, N(C.sub.1-10 alkanol)imidazolidine, an N(C.sub.1-10 alkanol)piperidine, or an N(C.sub.1-10 alkanol)piperazine. In some embodiments the alkanolamine is a mono(C.sub.1-4 alkanol)amine, a di(C.sub.1-4 alkanol)amine, a tri(C.sub.1-4 alkanol)amine, an N(C.sub.1-4 alkyl) mono(C.sub.2-4 alkanol)amine, an N(C.sub.1-4 alkyl) di(C.sub.2-4 alkanol)amine, an N,N-di(C.sub.1-4 alkyl) (C.sub.2-4 alkanol)amine, an N(C.sub.1-4 alkanol)pyrrolidine, N(C.sub.1-4 alkanol)imidazolidine, an N(C.sub.1-4 alkanol)piperidine, or an N(C.sub.1-4 alkanol)piperazine Specific alkanolamines are monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), methyl diethanolamine, isopropanolamine, diisopropanolamine, and (2-hydroxyethyl)piperazine. A combination comprising at least one of the foregoing alkanolamines can be used.

(3) In some embodiments, the alkanolamine is triethanolamine. Methods for the manufacture of triethanolamine are known. For example, triethanolamine compositions can be made by a process that comprises distilling triethanolamine from a mixture that includes at least diethanolamine and triethanolamine in the presence of phosphorous acid (H.sub.3PO.sub.3). A method of preparation and distillation of triethanolamine is described in, for example, U.S. Pat. No. 6,323,371.

(4) In an embodiment, the borane complex is of the formula
L.BR.sub.aH.sub.3-a
wherein L is ammonia (NH.sub.3), hydrazine (N.sub.2H.sub.4), an organic amine, a thioether, an organic phosphine, or a heterocycle as further described below; each R is independently the same or different, and is a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein two R form a ring with the boron atom; and a is 0 to 2. Preferably the ring is a 4- to 6-membered ring optionally containing one or two nitrogen or oxygen ring members. Preferably each R is independently a C.sub.1-4 alkyl group, a C.sub.3-6 cycloalkyl group, or a C.sub.6 aromatic group, and a is 0 to 2.

(5) When L is ammonia (NH.sub.3), the borane complex is of the formula
H.sub.3N.BR.sub.aH.sub.3-a
wherein R is as defined above, and a is 0 to 2. In some embodiments L is ammonia and a is zero, such that the borane complex is of the formula H.sub.3N.BH.sub.3, i.e., NBH.sub.6. In some embodiments a is 1 or 2, and R is as defined above, or preferably each R is independently a C.sub.1-6 alkyl group, a C.sub.3-6 cycloalkyl group, or a C.sub.6 aromatic group, optionally wherein two R form a ring with the boron atom; and more preferably each R is the same, for example the same C.sub.1-3 alkyl group.

(6) When the organic amine is selected as L, exemplary organic amines are a C.sub.1-24 amine, preferably a C.sub.1-24 amine of the formula:

(7) ##STR00001##
wherein each R.sup.1 is independently the same or different, and is hydrogen, provided that not all R.sup.1 are hydrogen; or a C.sub.1-8 hydrocarbyl group, optionally wherein any two R.sup.1 form a ring with the nitrogen atom. In some embodiments each R.sup.1 is independently hydrogen, a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-18 aromatic group, or a C.sub.3-15 heteroaromatic group, or any two R.sup.1 together form a C.sub.2-6 ring with the nitrogen atom that can optionally have 1 or 2 heteroatoms as ring members, and provided that not all R.sup.1 are hydrogen. Preferably in some embodiments each R.sup.1 is independently hydrogen or a C.sub.1-6 alkyl group, most preferably hydrogen or a C.sub.1-2 alkyl group, again provided that not all R.sup.1 are hydrogen. Preferably in other embodiments, two R.sup.1 are joined to form a 5- or 6-membered ring with the nitrogen, optionally further containing a nitrogen or oxygen atom as a ring member.

(8) When the thioether is selected as L, examples of thioethers include a C.sub.2-20 thioether, preferably a C.sub.2-20 thioether of the formula:

(9) ##STR00002##
wherein each R.sup.2 is independently the same or different, and is a C.sub.1-10 hydrocarbyl group. In some embodiments, each R.sup.2 is independently a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group. Preferably each R.sup.2 is independently a C.sub.1-6 alkyl group, most preferably a C.sub.1-2 alkyl group.

(10) Where the organic phosphine is selected as L, suitable organic phosphines include an organic phosphine substituted with three C.sub.1-12 hydrocarbyl groups, preferably an organic phosphine of the formula:

(11) ##STR00003##
wherein each R.sup.3 is independently the same or different, and is a C.sub.1-12 hydrocarbyl group. In some embodiments each R.sup.3 is independently a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group. Preferably each R.sup.3 is independently a C.sub.1-6 alkyl group or C.sub.6 aromatic group, most preferably a C.sub.1-4 alkyl group or C.sub.6 aromatic group.

(12) When the heterocycle is selected as L, examples of heterocycles are a C.sub.3-18 heterocycle. In some embodiments, the heterocycle is a C.sub.3-18 aliphatic heterocycle, or a C.sub.3-18 aromatic heterocycle. Examples of C.sub.3-18 aliphatic heterocycles are a C.sub.3-18 aliphatic heterocycle with 3 to 12 ring members wherein 1 to 10, or 1 to 8, or 1 to 6, or 1 to 4 ring members are each independently the same or different, and are a nitrogen, oxygen, phosphorus, silicon, or sulfur. In some embodiments the heterocycle is a C.sub.3-12 aliphatic heterocycle with 3 to 8 ring members wherein 1 to 6, or 1 to 5, or 1 to 4, or 1 to 3 ring members are each independently the same or different, and are a nitrogen, oxygen, or sulfur. Preferably the heterocycle is a C.sub.3-12 aliphatic heterocycle with 5 to 7 ring members wherein 1 or 2 ring members are each independently the same or different, and are a nitrogen, oxygen, or sulfur. In some embodiments the heterocycle is an aliphatic heterocycle of the formulas

(13) ##STR00004##
wherein each R.sup.4 is independently the same or different, and is a C.sub.1-6 alkyl group, a C.sub.1-6 alkoxy group, a halogen, nitrile, or nitro group, R.sup.5 is hydrogen or a C.sub.1-6 alkyl group; e is 0 to 4, preferably 0; f is 0 to 3, preferably 0; n is 1 to 2, and m is 1 to 2, preferably 2.

(14) Most preferably, the aliphatic heterocycle is of the formula

(15) ##STR00005##
Aliphatic heterocycles of these formulas are commonly known as tetrahydrofuran or morpholine.

(16) Exemplary C.sub.3-18 aromatic heterocycles include a C.sub.3-18 aromatic heterocycle with 1 to 3 rings and 5 to 14 ring members wherein 1 to 10, or 1 to 6, or 1 to 4 ring members are each nitrogen, oxygen, or sulfur; preferably a C.sub.3-18 aromatic heterocycle with 1 or 2 rings and 5 to 10 ring members wherein 1, 2, or 3 ring members are each independently the same or different, and are a nitrogen, oxygen, or sulfur, more preferably a C.sub.3-18 aromatic heterocycle with 1 ring and 5 or 6 ring members wherein 1, 2, 3 ring members are each independently the same or different, and are a nitrogen, oxygen, or sulfur, most preferably an aromatic heterocycle of the formula

(17) ##STR00006##
wherein each R.sup.6 is independently the same or different, and is a C.sub.1-12 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, more preferably a C.sub.1-6 alkyl group, and f is 0 to 5.

(18) Most preferably, the C.sub.3-18 aromatic heterocycles include pyridine, i.e. f is 0.

(19) In an embodiment, the borane complex is of the formula
(G.sup.+c).sub.x(B.sub.yH.sub.z).sup.xc
wherein G is an ammonium ion, a quaternary ammonium ion, a tertiary sulfonium ion, or a quaternary organic phosphonium ion, c is 1 to 3, x is 1 to 2, y is 2 to 20, and z is 4 to 14.

(20) In other embodiments, the borane complex is of the formula

(21) ##STR00007##
wherein each R.sup.7 is independently the same or different and is a C.sub.1-8 alkyl or a C.sub.1-8 alkoxy.

(22) In some preferred embodiments, the borane complex is of the formula (R.sup.1).sub.3N.BRH.sub.2, wherein each R.sup.1 is as defined above, and is specifically a hydrogen, a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, or two R.sup.1 are joined to form a 5- or 6-membered ring optionally having a nitrogen or oxygen in the ring; and R is as defined above, and is specifically a C.sub.1-12 alkyl group or a C.sub.3-8 cycloalkyl group.

(23) In other preferred embodiments, the borane complex is of the formula (R.sup.1).sub.3N.B R.sub.2H, wherein each R.sup.1 is as defined above, preferably wherein each R.sup.1 is independently the same or different, and is hydrogen, a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group provided that provided that not all R.sup.1 are hydrogen or two R.sup.1 are joined to form a 5- or 6-membered ring optionally having a nitrogen or oxygen in the ring; and each R.sup.8 is independently the same or different, and is as described above, preferably a C.sub.1-12 alkyl group or a C.sub.3-8 cycloalkyl group.

(24) Specific borane complexes include a borane-ammonia of the formula H.sub.3N.BH.sub.3, i.e. NBH.sub.6, borane-dimethylamine, borane-trimethyl amine, borane-triethyl amine, borane-tetrahydrofuran, borane-morpholine, borane-pyridine, or a combination comprising any one or more of the foregoing.

(25) Many of the above-described complexes are commercially available. Also, methods for the manufacture of the above-described complexes are known. For example, borane ammonia can be prepared from an alkali metal borohydride and ammonium salts, e.g., sodium borohydride and ammonium chloride, or by reacting diethyl ether-borane with ammonia. A process for the synthesis of ammonia borane is described in, for example, U.S. Pat. No. 7,897,129. Alkylaminoboranes can be obtained by reaction of an alkali metal borohydride with an alkylammonium salts. Other boranes are described, for example, in Staubitz, A. et al., Chemical Reviews, Vol. 110, No. 7, pp. 4023-78 (2010), and references cited therein; and in Brown, H. C. et al., Organic Syntheses via Boranes, John Wiley & Sons (1975) and references cited therein; and in Brunel J. M. et al., Coordination Chemistry Reviews, Vols. 178-180, Part 1 pp. 665-698 (1998) and references cited therein.

(26) The alkanolamine compositions can have any level of color before treatment with a borane complex, including low, very low, or no color before treatment with the borane complex. As described in more detail below, treatment of alkanolamine compositions having low, very, low, or no color can be to prevent color formation over time. For convenience, any alkanolamine composition treated with a borane complex as described herein can be referred to as a color-reduced alkanolamine composition.

(27) Contacting the alkanolamines with the borane complex can be at a temperature from 20 C. to 250 C., preferably 20 C. to 150 C., more preferably 20 C. to 90 C., more preferably still 20 C. to 45 C., or 20 C. to 30 C. Lower temperatures (e.g., 20 C. to 30 C. are preferred to prevent side reactions that can cause color. Contacting can generally be for a selected period of time, for example, 10 minutes to 50 hours, preferably 30 minutes to 30 hours, more preferably 1 hour to 24 hours. Contacting can be by mixing of the alkanolamine and the borane complex, during or after the contacting. It is to be understood that the borane complex is generally not subsequently quenched or removed from the alkanolamine, such that the above contacting temperatures and times may simply be for an initial period before the alkanolamine is further processed, for example transported or packaged for storage or transportation.

(28) For the purpose of contacting, the borane complex is used neat or in solution. When used in solution, the borane complex is dissolved in a solvent before contacting to form a solution. Examples of the solvent are water and alcohol to form an aqueous or alcoholic solution, preferably an aqueous solution, a C.sub.1-3 alcoholic solution, more preferably a C.sub.1-2 alcoholic solution. In these solutions, the concentration of the borane complex is 1 to 30 weight percent (wt %), based on total weight of the solution, preferably 1 to 20 wt %, more preferably 1 to 20 wt %, even more preferably 1 to 10 wt %.

(29) When contacting the alkanolamine with the borane complex, the borane complex is generally present in an amount effective to reduce color. For example, the concentration of the borane complex can be from 1 to 5,000 ppm (where ppm denotes parts per million by weight based on the weight of the alkanolamine), preferably 5 to 2,000 ppm, more preferably 5 to 1,000 ppm, more preferably still 5 to 500 ppm.

(30) Contacting the alkanolamines with the borane complex reduces any initial color, e.g., color bodies and color contaminants, present in the alkanolamines before such contact, and provides the color-reduced alkanolamine compositions herein. The inventors hereof have advantageously found that such initial color is reduced during or after contacting to the extent that the resultant alkanolamine compositions are colorless or near colorless. Without wishing to be bound by any specific theory, borane is believed to be liberated during contacting and acts as a reducing agent, of any color bodies or contaminants that cause color bodies present in the alkanolamines.

(31) The color-reduced alkanolamine compositions produced by the methods described herein, for example reduced-color triethanolamine compositions, can have significantly reduced or low color. For example, the Hazen color, specifically the Platinum-Cobalt Color Value as determined according to Test Method ASTM D1209 (PtCo color value) can be less than 50, and preferably less than 30. It has surprisingly been found that the PtCo color value can be 0 to 20.

(32) Further advantageously, the color-reduced alkanolamine compositions produced by these methods, specifically reduced-color triethanolamine compositions, can maintain these very low color values over extended periods. The borane complexes can thus prevent color increases over time. For example, the color-reduced alkanolamine compositions produced by the methods described herein, specifically color-reduced triethanolamine compositions, when stored at room temperature (e.g., 20 C. to 25 C.) for a period of six months to one year, or one to two years, or one to three years, or one year to six years, following the contacting, can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20. In some embodiments, the color-reduced alkanolamine compositions can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20, after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting when protected from light. Storage as used herein includes periods where the compositions are not in active use, for example where the compositions are transported. Protected from light can mean that the compositions are stored under conditions where visible light is excluded for at least 90% of the time during storage.

(33) In other embodiments, the color-reduced alkanolamine compositions produced by the methods described herein, specifically color-reduced triethanolamine compositions, can have a PtCo color value that does not increase by more than 40%, preferably more than 30%, more preferably more than 20% when stored at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting. In some embodiments, the color-reduced alkanolamine compositions produced by the methods described herein, specifically color-reduced triethanolamine compositions, can have a PtCo color value that does not increase by more than 40%, preferably more than 30%, more preferably more than 20% when stored at room temperature (e.g., 20 C. to 25 C.) for a period for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, when protected from light.

(34) The alkanolamine compositions produced by these methods are also color-stable at elevated temperatures. Thus, the color-reduced alkanolamine compositions produced by the methods described herein, specifically color-reduced triethanolamine compositions, when stored at 30 C. to 50 C., or 40 to 50 C., or 45 C., for a period of one month to three years, or one month to two years, or three months to one year, or four to eight months following the contacting, can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20. In some embodiments, the color-reduced alkanolamine compositions can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20, after storage at 30 C. to 50 C., or 40 C. to 50 C., or 45 C., for a period of one month to three years, or one month to two years, or three months to one year, or 4 to 8 months following the contacting when protected from light. In some embodiments, the color-reduced alkanolamine compositions produced by the methods described herein, specifically color-reduced triethanolamine compositions, can have a PtCo color value that does not increase by more than 40%, preferably more than 30%, more preferably more than 20% when stored at 30 C. to 50 C., or 40 C. to 50 C., or 45 C., for a period of one month to three years, or one month to two years, or three months to one year, or 4 to 8 months when protected from light.

(35) As mentioned above, an advantage of this method is that the alkanolamine compositions do not require subsequent purification or processing after being contacted with the borane complex. Residual boron levels in the color-reduced compositions can accordingly be 0.1 to 5000 ppm of residual boron, preferably 5 to 2,000 ppm, more preferably 5 to 500 ppm, or 1 to 100 ppm. The term residual boron encompasses boron in any form, for example in elemental form, as the complex, or in combination with one or more boron complex reaction products. The term residual boron further includes any boron present in the alkanolamine compositions before or after addition of the boron complex, and may thus be higher than the amount of boron added as the complex.

(36) Accordingly, color-reduced alkanolamine compositions comprising an alkanolamine and 0.1 to 5000 ppm of residual boron, preferably 5 to 2,000 ppm of residual boron, more preferably 5 to 500 ppm of residual boron, can have a PtCo color value of less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value can be 0 to 20. In some embodiments, color-reduced triethanolamine compositions comprising triethanolamine and 0.1 to 5,000 ppm of residual boron, preferably 5 to 2,000 ppm of residual boron, more preferably 5 to 500 ppm of residual boron, can have a PtCo color value of less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value of the color-reduced triethanolamine composition comprising residual boron can be 0 to 20.

(37) In still other embodiments, unreacted (residual) boron complex can remain in the color-reduced compositions. Accordingly, color-reduced alkanolamine compositions comprising an alkanolamine and 0.1 to 4,900 ppm of residual boron complex, or 0.1 to 3,000 ppm of residual boron complex, or 0.1 to 1,000 ppm of residual boron complex, or 0.1 to 500 ppm of residual boron complex can have a PtCo color value of less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value can be 0 to 20. In some embodiments, color-reduced triethanolamine compositions comprising triethanolamine and 0.1 to 4,990 ppm of residual boron complex, or 0.1 to 3,000 ppm of residual boron complex, or 0.1 to 1,000 ppm of residual boron complex, or 0.1 to 500 ppm of residual boron complex, can have a PtCo color value of less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value of the color-reduced triethanolamine composition comprising residual boron complex can be 0 to 20.

(38) The color-reduced alkanolamine compositions can maintain these very low color values over extended time. For example the color-reduced alkanolamine compositions comprising an alkanolamine and 0.1 to 5000 ppm of residual boron, or 5 to 2,000 ppm of residual boron, or 5 to 500 ppm of residual boron, after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting, can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20. The color-reduced alkanolamine compositions can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20 after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, when the compositions are protected from light.

(39) In some embodiments, color-reduced triethanolamine compositions comprising triethanolamine and 0.1 to 5000 ppm of residual boron, preferably 5 to 2,000 ppm of residual boron, more preferably 5 to 500 ppm of residual boron, after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting, can have a PtCo color value less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value of the color-reduced triethanolamine composition comprising residual boron can be 0 to 20 for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following contacting. The color-reduced triethanolamine compositions can have PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20 after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years after contacting when the compositions are protected from light.

(40) In some embodiments where the compositions contain residual boron complex, the color-reduced alkanolamine compositions can maintain these very low color values over extended time. For example the color-reduced alkanolamine compositions comprising an alkanolamine and 0.1 to 4,500 ppm of residual boron complex, or 1 to 2,000 ppm of residual boron complex, or 5 to 1,000 ppm of residual boron complex, after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting, can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20. The color-reduced alkanolamine compositions can have a PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20 after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years when the compositions are protected from light.

(41) In some embodiments, color-reduced triethanolamine compositions comprising triethanolamine and 0.1 to 4,990 ppm of residual boron complex, or 0.1 to 3,000 ppm of residual boron complex, or 0.1 to 1,000 ppm of residual boron complex, or 0.1 to 500 ppm of residual boron complex, after storage at room temperature (e.g., 20 C. to 25 C.) for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following the contacting, can have a PtCo color value less than 50, and preferably less than 30. In a preferred embodiment, the PtCo color value of the color-reduced triethanolamine composition comprising residual boron complex can be 0 to 20 for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, following contacting. The color-reduced triethanolamine compositions can have PtCo color value of less than 50, preferably less than 30, more preferably 0 to 20 after storage at room temperature (e.g., 20 C. to 25 C.) when the compositions are protected from light.

(42) The reduced-color alkanolamine compositions can include water. For example, water can be present in the compositions in an amount of less than 10 weight percent (wt. %), preferably less than 5 wt. %, more preferably less than 3 wt. %, even more preferably less than 1 wt. %, even more preferably still less than 0.5 wt. %, based on the total weight of the reduced-color alkanolamine composition.

(43) The alkanolamine compositions can be used for example as emulsifiers, surfactants, solvents, co-solvents, pH adjusting agents, or buffering agents, as well as in any other known uses, in a wide variety of applications. Such applications include household goods, cement production, cosmetics, medicine, printing, chemical manufacturing (e.g., as a solvent, catalyst, or reactant, and electroless plating. Some products that can include the alkanolamines include liquid laundry detergents, dishwashing liquids, general cleaners, hand cleaners, polishes, metalworking fluids, paints, shaving cream, and printing inks.

(44) The following Examples are provided for illustrative purposes only and are not to be construed as limiting in any manner.

EXAMPLES

(45) Color determination was carried out on a Lico 690 Colorimeter from Koehler Instrument Company in accordance with the PtCo test method as described in ASTM D1209 (2011). Results are reported as PtCo Color Values.

Example 1

(46) Color Stability of a Color-Reduced Triethanolamine Composition

(47) Triethanolamine (1000 g, Sigma Aldrich, 99% purity) having a PtCo Color Value of 23 is mixed with a borane-ammonia complex (100 mg, obtained from Sigma Aldrich, 95% purity). The mixture is vigorously shaken to allow the borane-ammonia complex to distribute homogenously in the triethanolamine Over a period of 6 hours the mixture clears. A sample is taken for color analysis, and found to have a PtCo Color Value that was calculated to be less than 15 after 2 years at room temperature (20-25 C.).

Example 2

(48) A sample of triethanolamine (TEA) with a borane-ammonia complex was stored in an oven at 45 C. for six months. The sample was removed, cooled, and found to have a PtCo Color Value of 20. According to Van't Hoff's law, chemical reaction rates double to quadruple for every 10 degrees Celsius increase in temperature. It is therefore calculated that if TEA with borane complex was stored at room temperature (25 C.), its color index would be less than 20 for as long as 6 years (if reaction rate quadrupled every 10 C. increase).

(49) The methods and compositions are further illustrated by the following embodiments.

(50) Embodiment 1: A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with a color-reducing amount of a borane complex effective to provide an alkanolamine composition having a Platinum-Cobalt Color Value, Test Method ASTM D1209, of less than 50, preferably less than 30, more preferably 0 to 20.

(51) Embodiment 2: The method of embodiment 1, wherein the alkanolamine is a mono(C.sub.1-10 alkanol)amine, a di(C.sub.1-10 alkanol)amine, a tri(C.sub.1-10 alkanol)amine, an N(C.sub.1-10 alkyl) di(C.sub.2-4 alkanol)amine, an N,N-di(C.sub.1-10 alkyl) (C.sub.2-4 alkanol)amine, an N(C.sub.1-10 alkanol)pyrrolidine, N(C.sub.1-10 alkanol)imidazolidine, an N(C.sub.1-10 alkanol)piperidine, an N(C.sub.1-10 alkanol)piperazine or a combination comprising at least one of the foregoing; preferably monoethanolamine, diethanolamine, methyldiethanolamine, isopropanolamine, diisopropanolamine, (2-hydroxyethyl)piperazine, or a combination comprising at least one of the foregoing.

(52) Embodiment 3: The method of embodiment 1, wherein the alkanolamine is a tri(C.sub.1-10 alkanol)amine, preferably triethanolamine.

(53) Embodiment 4: The method of any one or more of embodiments 1 to 3, wherein: the borane complex is of the formula L.BR.sub.aH.sub.3-a wherein L is ammonia, hydrazine, an organic amine, a thioether, an organic phosphine, or a heterocycle, each R is independently a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein any two R form a ring with the boron atom; and a is 0 to 2; the borane complex is of the formula (G.sup.+c).sub.x(B.sub.yH.sub.z).sup.xc, wherein G is an ammonium ion, a quaternary ammonium ion, a tertiary sulfonium ion, or a quaternary organic phosphonium ion, c is 1 to 3, x is 1 to 2, y is 2 to 20, and z is 4 to 14; or the borane complex is of the formula

(54) ##STR00008##
wherein each R.sup.7 is independently a C.sub.1-8 alkyl or a C.sub.1-8 alkoxy.

(55) Embodiment 5: The method of any one or more of embodiments 1 to 4, wherein: the borane complex is of the formula L.BH.sub.3, wherein L is ammonia or a C.sub.1-24 organic amine, an organic phosphine substituted with three C.sub.1-12 hydrocarbyl groups, a C.sub.3-18 heterocycle, or a C.sub.2-20 thioether; or the borane complex is of the formula H.sub.3N.BR.sub.aH.sub.3-a, wherein a is 1 or 2, and each R is independently the same or different, and is a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein two R form a ring with the boron atom, preferably wherein each R is independently a C.sub.1-6 alkyl group, a C.sub.3-6 cycloalkyl group, or a C.sub.6 aromatic group.

(56) Embodiment 6: The method of embodiment 5, wherein L is ammonia or a C.sub.1-24 amine of the formula (R.sup.1).sub.3N wherein each R.sup.1 is independently hydrogen or a C.sub.1-8 hydrocarbyl group, optionally wherein any two R.sup.1 form a ring with the nitrogen atom, and provided that not all R.sup.1 are hydrogen; or hydrogen, a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-18 aromatic group, or a C.sub.3-15 heteroaromatic group, or any two R.sup.1 together form a C.sub.2-6 ring with the nitrogen atom that can optionally have 1 or 2 heteroatoms as ring members, and provided that not all R.sup.1 are hydrogen, more preferably hydrogen or a C.sub.1-6 alkyl group, or two R.sup.1 are joined to form a 5- or 6-membered ring with the nitrogen, optionally further containing a nitrogen or oxygen atom as a ring member, and provided that not all R.sup.1 are hydrogen; most preferably hydrogen or a C.sub.1-2 alkyl group, or two R.sup.1 are joined to form a morpholine, and provided that not all R.sup.1 are hydrogen.

(57) Embodiment 7: The method of embodiment 5, wherein L is an organic phosphine of the formula (R.sup.3).sub.3P, wherein each R.sup.3 is independently a C.sub.1-12 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, more preferably a C.sub.1-6 alkyl group or C.sub.6 aromatic group, most preferably a C.sub.1-4 alkyl group or C.sub.6 aromatic group.

(58) Embodiment 8: The method of embodiment 5, wherein L is a C.sub.2-20 thioether of the formula (R.sup.2).sub.2S wherein each R.sup.2 is independently a C.sub.1-10 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, more preferably a C.sub.1-6 alkyl group, most preferably a C.sub.1-2 alkyl group.

(59) Embodiment 9: The method of embodiment 5, wherein L is a C.sub.3-18 aliphatic heterocycle with 3 to 12 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, phosphorus, silicon, or sulfur; preferably a C.sub.3-12 aliphatic heterocycle with 3 to 8 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur, more preferably a C.sub.3-12 aliphatic heterocycle with 5 to 7 ring members wherein 1 or 2 ring members are each independently nitrogen, oxygen, or sulfur, still more preferably an aliphatic heterocycle of the formulas

(60) ##STR00009##
wherein each R.sup.4 is independently a C.sub.1-6 alkyl group, a C.sub.1-6 alkoxy group, a halogen, nitrile, or nitro group, R.sup.5 is hydrogen or a C.sub.1-6 alkyl group, e is 0 to 4, preferably 0, f is 0 to 3, preferably 0, n is 1 to 2, and m is 1 to 2, preferably 2; most preferably an aliphatic heterocycle of the formulas

(61) ##STR00010##

(62) Embodiment 10: The method of embodiment 5, wherein L is a C.sub.3-18 aromatic heterocycle with 1 to 3 rings and 5 to 14 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur; preferably a C.sub.3-18 aromatic heterocycle with 1 or 2 rings and 5 to 10 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur, more preferably a C.sub.3-18 aromatic heterocycle with 1 ring and 5 or 6 ring members wherein 1, 2, 3 ring members are each independently nitrogen, oxygen, or sulfur, most preferably an aromatic heterocycle of the formula

(63) ##STR00011##
wherein each R.sup.6 is independently a C.sub.1-12 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, more preferably a C.sub.1-6 alkyl group, and f is 0 to 5;

(64) most preferably wherein L is pyridine.

(65) Embodiment 11: The method of embodiment 5, wherein L is ammonia, dimethylamine, trimethylamine, triethylamine, tetrahydrofuran, morpholine, or pyridine.

(66) Embodiment 12: The method of any one or more of embodiments 1 to 11, wherein contacting is with 1 to 5,000 ppm by weight of the borane complex, or 5 to 2,000 ppm, or 5 to 1,000 ppm, based on the weight of the alkanolamine.

(67) Embodiment 13: The method of any one or more of embodiments 1 to 12, wherein the borane complex is dissolved in a solvent before contacting, preferably an aqueous or alcoholic solvent, preferably an aqueous or a C.sub.1-2 alcoholic solvent.

(68) Embodiment 14: The method of embodiment 13, wherein the concentration of the borane complex in the solvent is 1 to 30 wt %, based on total weight of the components, preferably 1 to 20 wt %, more preferably 1 to 20 wt %, even more preferably 1 to 10 wt %.

(69) Embodiment 15: The method of any one or more of embodiments 1 to 14, further comprising mixing the alkanolamine and the borane complex during or after the contacting.

(70) Embodiment 16: The method of any one or more of embodiments 1 to 15, wherein the contacting is at 20 C. to 250 C., preferably 20 C. to 40 C., more preferably 20 C. to 30 C.; and for 10 minutes to 50 hours.

(71) Embodiment 17: The method of any one or more of embodiments 1 to 16, wherein the Platinum-Cobalt Color Value, Test Method ASTM D1209, does not increase by more than 40%, preferably more than 30%, or more preferably more than 20% for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, after storage at room temperature.

(72) Embodiment 18: The method of any one or more of embodiments 1 to 17, wherein the Platinum-Cobalt Color Value, Test Method ASTM D1209, does not increase by more than 40%, preferably more than 30%, more preferably more than 20% for a period of one month to three years, or one month to two years, or three months to one year, or 4 to 8 months after storage at 45 C.

(73) Embodiment 19: A color-reduced alkanolamine composition, the composition comprising: triethanolamine and an effective color-reducing amount of a borane complex, wherein the composition has a Platinum-Cobalt Color Value, Test Method ASTM D1209, of less than 50, preferably less than 30, more preferably 0 to less than or equal to 20.

(74) Embodiment 20: The composition of embodiment 19, wherein the alkanolamine is a mono(C.sub.1-10 alkanol)amine, a di(C.sub.1-10 alkanol)amine, a tri(C.sub.1-10 alkanol)amine, an N(C.sub.1-10 alkyl) di(C.sub.2-4 alkanol)amine, an N,N-di(C.sub.1-10 alkyl) (C.sub.2-4 alkanol)amine, or a combination comprising at least one of the foregoing; preferably monoethanolamine, diethanolamine, methyldiethanolamine, isopropanolamine, diisopropanolamine, (2-hydroxyethyl)piperazine, or a combination comprising at least one of the foregoing.

(75) Embodiment 21: The composition of any one or more of embodiments 19 to 20, wherein the alkanolamine is a tri(C.sub.1-10 alkanol)amine, preferably triethanolamine.

(76) Embodiment 22: The composition of any one or more of embodiments 19 to 21, wherein: the borane complex is of the formula L.BR.sub.aH.sub.3-a, wherein L is ammonia, hydrazine, an organic amine, a thioether, an organic phosphine, or a heterocycle; each R is independently is a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein any two R form a ring with the boron atom; and a is 0 to 2; the borane complex is of the formula (G.sup.+c).sub.x(B.sub.yH.sub.z).sup.xc, wherein G is an ammonium ion, a quaternary ammonium ion, a tertiary sulfonium ion, or a quaternary organic phosphonium ion, c is 1 to 3, x is 1 to 2, y is 2 to 20, and z is 4 to 14; or the borane complex is of the formula

(77) ##STR00012##
wherein each R.sup.7 is independently a C.sub.1-8 alkyl or a C.sub.1-8 alkoxy.

(78) Embodiment 23: The composition of any one or more of embodiments 19 to 22, wherein: the borane complex is of the formula LBH.sub.3 wherein each L is independently ammonia or a C.sub.1-24 organic amine, an organic phosphine substituted with three C.sub.1-12 hydrocarbyl groups, a C.sub.3-18 heterocycle, or a C.sub.2-20 thioether; or; or the borane complex is of the formula H.sub.3N.BR.sub.aH.sub.3-a, wherein a is 1 or 2, and each R is independently the same or different, and is a C.sub.1-12 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, optionally wherein two R form a ring with the boron atom, preferably wherein each R is independently a C.sub.1-6 alkyl group, a C.sub.3-6 cycloalkyl group, or a C.sub.6 aromatic group.

(79) Embodiment 24: The composition of embodiment 23, wherein L is ammonia or a C.sub.1-24 amine of the formula (R.sup.1).sub.3N, wherein each R.sup.1 is the independently hydrogen or a C.sub.1-8 hydrocarbyl group, optionally wherein any two R.sup.1 form a ring with the nitrogen atom, and provided that not all R.sup.1 are hydrogen, or hydrogen, a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-18 aromatic group, or a C.sub.3-15 heteroaromatic group, or any two R.sup.1 together form a C.sub.2-6 ring with the nitrogen atom that can optionally have 1 or 2 heteroatoms as ring members, and provided that not all R.sup.1 are hydrogen, more preferably hydrogen or a C.sub.1-6 alkyl group, two R.sup.1 are joined to form a 5- or 6-membered ring with the nitrogen, optionally further containing a nitrogen or oxygen atom as a ring member, and provided that not all R.sup.1 are hydrogen most preferably hydrogen or a C.sub.1-2 alkyl group, or two R.sup.1 are joined to form a morpholine, and provided that not all R.sup.1 are hydrogen.

(80) Embodiment 25: The composition of embodiment 23, wherein L is an organic phosphine of the formula (R.sup.3).sub.3P,

(81) wherein each R.sup.3 is independently a C.sub.1-12 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, more preferably a C.sub.1-6 alkyl group or C.sub.6 aromatic group, most preferably a C.sub.1-4 alkyl group or C.sub.6 aromatic group.

(82) Embodiment 26: The composition of embodiment 23, wherein L is a C.sub.2-20 thioether of the formula (R.sup.2).sub.3S, wherein each R.sup.2 is independently a C.sub.1-10 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, a C.sub.3-7 heterocycloalkyl group, a C.sub.6-10 aromatic group, or a C.sub.3-15 heteroaromatic group, more preferably a C.sub.1-6 alkyl group, most preferably a C.sub.1-2 alkyl group.

(83) Embodiment 27: The composition of embodiment 23, wherein L is a C.sub.3-18 aliphatic heterocycle with 3 to 12 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, phosphorus, silicon, or sulfur; preferably a C.sub.3-12 aliphatic heterocycle with 3 to 8 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur, more preferably a C.sub.3-12 aliphatic heterocycle with 5 to 7 ring members wherein 1 or 2 ring members are each independently nitrogen, oxygen, or sulfur, still more preferably an aliphatic heterocycle of the formulas

(84) ##STR00013##
wherein each R.sup.5 is independently a C.sub.1-6 alkyl group, a C.sub.1-6 alkoxy group, a halogen, nitrile, or nitro group, R.sup.6 is hydrogen or a C.sub.1-6 alkyl group, e is 0 to 4, preferably 0, f is 0 to 3, preferably n0 is 1 to 2, and m is 1 to 2, preferably 2; most preferably an aliphatic heterocycle of the formulas

(85) ##STR00014##

(86) Embodiment 28: The composition of embodiment 23, wherein L is a C.sub.3-18 aromatic heterocycle with 1 to 3 rings and 5 to 14 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur; preferably a C.sub.3-18 aromatic heterocycle with 1 or 2 rings and 5 to 10 ring members wherein 1, 2, or 3 ring members are each independently nitrogen, oxygen, or sulfur, more preferably a C.sub.3-18 aromatic heterocycle with 1 ring and 5 or 6 ring members wherein 1, 2, 3 ring members are each independently nitrogen, oxygen, or sulfur, most preferably an aromatic heterocycle of the formula

(87) ##STR00015##
wherein each R.sup.6 is independently a C.sub.1-12 hydrocarbyl group, preferably a C.sub.1-8 alkyl group, a C.sub.3-8 cycloalkyl group, or a C.sub.6-10 aromatic group, more preferably a C.sub.1-6 alkyl group, and f is 0 to 5; most preferably wherein L is pyridine.

(88) Embodiment 29: The composition of embodiment 23, wherein L is ammonia, dimethylamine, trimethylamine, triethylamine, tetrahydrofuran, morpholine, or pyridine.

(89) Embodiment 30: The composition of any one or more of embodiments 19 to 29, comprising 1 to 5,000 ppm by weight of the boron complex, preferably 5 to 2,000 ppm, or more preferably 5 to 1,000 ppm, based on the parts by weight of the triethanolamine

(90) Embodiment 31: The composition of any one or more of embodiments 19 to 30, comprising less than 5 wt % of water, preferably less than 1 wt % of water, based on the total weight of the triethanolamine.

(91) Embodiment 32: The composition of any one or more of embodiments 19 to 31, wherein the Platinum-Cobalt Color Value, Test Method ASTM D1209, does not increase by more than 40%, preferably more than 30%, more preferably more than 20% for a period of six months to eight years, or one to eight years, or two to eight years, or three to seven years, or four to six years, after storage at room temperature.

(92) Embodiment 33: The composition of any one or more of embodiments 19 to 32, wherein the Platinum-Cobalt Color Value, Test Method ASTM D1209, does not increase by more than 40%, preferably more than 30%, more preferably more than 20% for a period of one month to three years, or one month to two years, or three months to one year, or 4 to 8 months, after storage at 45 C.

(93) In general, the methods and compositions can alternatively comprise, consist of, or consist essentially of, any appropriate steps or components herein disclosed. The methods or compositions can additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any steps, components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and/or objectives described herein.

(94) The singular forms a, an, and the include plural referents unless the context clearly dictates otherwise. Or means and/or. The endpoints of all ranges directed to the same component or property are inclusive and independently combinable. Disclosure of a narrower range or more specific group in addition to a broader range is not a disclaimer of the broader range or larger group. Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs. A combination is inclusive of blends, mixtures, alloys, reaction products, and the like.

(95) All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in the incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.

(96) As used herein, the term hydrocarbyl includes groups containing carbon, hydrogen, and optionally one or more heteroatoms (e.g., 1, 2, 3, or 4 atoms such as halogen, O, N, S, P, or Si). Alkyl means a branched or straight chain, saturated, monovalent hydrocarbon group, e.g., methyl, ethyl, i-propyl, and n-butyl. Alkylene means a straight or branched chain, saturated, divalent hydrocarbon group (e.g., methylene (CH.sub.2) or propylene ((CH.sub.2).sub.3)). Alkenyl and alkenylene mean a monovalent or divalent, respectively, straight or branched chain hydrocarbon group having at least one carbon-carbon double bond (e.g., ethenyl (HCCH.sub.2) or propenylene (HC(CH.sub.3)CH.sub.2). Alkynyl means a straight or branched chain, monovalent hydrocarbon group having at least one carbon-carbon triple bond (e.g., ethynyl). Alkoxy means an alkyl group linked via an oxygen (i.e., alkyl-O), for example methoxy, ethoxy, and sec-butyloxy. Cycloalkyl and cycloalkylene mean a monovalent and divalent cyclic hydrocarbon group, respectively, of the formula C.sub.nH.sub.2n-x and C.sub.nH.sub.2n-2x.sup. wherein x is the number of cyclization(s). Aryl means a monovalent, monocyclic or polycyclic, aromatic group (e.g., phenyl or naphthyl). Arylene means a divalent, monocyclic or polycyclic, aromatic group (e.g., phenylene or naphthylene). The prefix halo means a group or compound including one more halogen (F, Cl, Br, or I) substituents, which can be the same or different. The prefix hetero means a group or compound that includes at least one ring member that is a heteroatom (e.g., 1, 2, or 3) heteroatoms, wherein each heteroatom is independently the same or different and is N, O, S, or P.

(97) Substituted means that the compound or group is substituted with at least one (e.g., 1, 2, 3, or 4) substituents instead of hydrogen, where each substituent is independently the same or different and is nitro (NO.sub.2), cyano (CN), hydroxy (OH), halogen, thiol (SH), thiocyano (SCN), C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, C.sub.1-6 haloalkyl, C.sub.1-9 alkoxy, C.sub.1-6 haloalkoxy, C.sub.3-12 cycloalkyl, C.sub.5-18 cycloalkenyl, C.sub.6-12 aryl, C.sub.7-13 arylalkylene (e.g, benzyl), C.sub.7-12 alkylarylene (e.g, toluyl), C.sub.4-12 heterocycloalkyl, C.sub.3-12 heteroaryl, C.sub.1-6 alkyl sulfonyl (S(O).sub.2-alkyl), C.sub.6-12 arylsulfonyl (S(O).sub.2-aryl), or tosyl (CH.sub.3C.sub.6H.sub.4SO.sub.2), provided that the substituted atom's normal valence is not exceeded, and that the substitution does not significantly adversely affect the manufacture, stability, or desired property of the compound. When a compound is substituted, the indicated number of carbon atoms is the total number of carbon atoms in the group, including those of the substituent(s).

(98) While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof.