COMPOSITION FOR REMOVING CHEMICAL RESIDUES AND USES THEREOF

Abstract

A decontamination composition with at least one primary neutralizing agent and at least one secondary neutralizing agent, for the removal of chemical residues, to a method for employing the composition, and the use of the composition for removing residues on materials, machines, and equipment soiled with chemicals of any type, such as a corrosive product or a chemical containing fluoride ions.

Claims

1-12. (canceled)

13. A decontamination composition comprising: at least one primary neutralizing agent (a) that is a complex based on aluminum and ethylenediaminetetraacetic acid and having a pKa of >4, at least one secondary neutralizing agent (b) selected from an amphoteric agent, the two pKa values of which meet the following conditions:
(pKa1+pKa2)/2>5
7>pKa1>4
11>pKa2>7 and an agent having at least one pKa of between 7 and 11, and mixtures thereof, water, optionally a color indicator or a mixture of color indicators (c), and optionally at least one additive (d), wherein said composition is free of salts H.sub.aX.sub.b in which H is an alkali metal or alkaline earth metal, X a halogen atom, a is an integer between 1 and 2, and b is an integer between 1 and 4.

14. The composition as claimed in claim 13, wherein said primary neutralizing agent is present in an amount ranging from 0.1% to 25% by weight, preferably from 10% to 20% by weight, and more preferably from 15% to 18% by weight, relative to the total weight of the composition.

15. The composition as claimed in claim 13, wherein said secondary neutralizing agent is selected from ascorbic acid and salts thereof, hydrogen carbonate and salts thereof, creatinine, glutathione, isoguanine, adenine, an amino acid and salts thereof, such as glutamic acid, aspartic acid, arginine, lysine, ornithine, cysteine, and mixtures thereof.

16. The composition as claimed in claim 15, wherein said secondary neutralizing agent is selected from sodium glutamate, lysine, ornithine, cysteine, and L-arginine.

17. The composition as claimed in claim 13, wherein said secondary neutralizing agent is present in an amount ranging from 0.1% to 50% by weight, preferably from 1% to 20% by weight, and more preferably from 5% to 15% by weight, relative to the total weight of the composition.

18. The composition as claimed in claim 13, wherein said color indicator or said mixture of color indicators has a color-change zone at a pH of between 1 and 7, preferably between 2 and 6, and more preferably between 2.5 and 5, and a color-change zone at a pH of between 8 and 13, preferably between 8.5 and 11, and more preferably between 9 and 10.

19. The composition as claimed in claim 18, wherein the color indicator is selected from methyl red, thymol blue, ethyl orange, methyl orange, tropaeolin OO, bromophenol blue, and mixtures thereof.

20. The composition as claimed in claim 18, wherein the color indicator or mixture of color indicators is present in an amount ranging from 0% to 5% by weight, preferably ranging from 0.001% to 1% by weight, and more preferably from 0.002% to 0.5% by weight, relative to the total weight of the composition.

21. The composition as claimed in claim 13, wherein the salt H.sub.aX.sub.b is at least one compound selected from the salt NaCl, the salt KCl, the salt NaF, and the salt NaBr.

22. The composition as claimed in claim 13, wherein the composition comprises: (a) from 5 to 25%, preferably from 8 to 20%, and more preferably from 10 to 17%, of a primary neutralizing agent, (b) from 1 to 50%, preferably from 5 to 15%, and more preferably from 8 to 13%, of a secondary neutralizing agent, (c) from 0% to 5%, preferably from 0.001% to 1%, and more preferably from 0.002% to 0.5%, of a color indicator or of a mixture of color indicators, (d) water, said percentages being percentages by weight relative to the total weight of the composition.

23. A decontamination method employing the composition as defined in claim 13, comprising the following steps: (1) dispersing the composition on a surface soiled with a chemical, (2) repeating step (1) until a neutral pH is obtained, preferably until a pH of between 5.5 and 9 is obtained, and (3) optionally rinsing with water to prevent colored crystals from appearing during drying of the decontaminated surface.

24. The decontamination method as claimed in claim 23, wherein said chemical is a corrosive product or is a chemical containing fluoride ions.

25. A method for decontaminating materials, machines, or equipment soiled with a chemical, comprising applying the composition as defined in claim 13 to said materials, machines, or equipment soiled with a chemical.

26. The method as claimed in claim 26, wherein said chemical is a corrosive product or is a chemical containing fluoride ions.

Description

DESCRIPTION OF FIGURES

[0062] FIG. 1 shows a graph depicting the neutralization of 1 M NaOH and 1 M HCl with the solution from example 1.

[0063] FIG. 2 shows a graph depicting the binding of fluoride present in 5 mL of 1 M NH.sub.4F with the solution from example 1.

[0064] FIG. 3 shows a graph depicting the neutralization of 1 M NaOH and 1 M HCl with the solution from example 2.

[0065] FIG. 4 shows a graph depicting the binding of fluoride present in 5 mL of 1 M NH.sub.4F with the solution from example 2.

[0066] FIG. 5 shows a graph depicting the neutralization of 1 M NaOH and 1 M HCl with the solution from example 3.

[0067] FIG. 6 shows a graph depicting the binding of fluoride present in 5 mL of 1 M NH.sub.4F with the solution from example 3.

[0068] The invention will now be illustrated by the non-restricting examples hereinbelow.

EXAMPLES

[0069] In the examples that follow, the following commercial products are used: [0070] Sodium L-glutamate monohydrate sold by MB Biomedicals, LLC, [0071] Methyl red sold by EMD Millipore Corporation, [0072] Thymol blue sold by Alfa Aesar, [0073] L-Arginine monohydrochloride sold by Alfa Aesar, [0074] L-Lysine hydrochloride sold by ThermoFisher (Kandel) GmbH, [0075] Ethyl orange sold by Alfa Aesar, [0076] Bromophenol blue sold by EMD Millipore Corporation, [0077] Sodium hydroxide sold by VWR Chemicals, [0078] Sodium aluminate sold by Sigma Aldrich, [0079] Ethylenediaminetetraacetic acid (EDTA) sold by Merck Millipore.

Example 1

[0080] A decontamination composition 1 was prepared that comprised:

TABLE-US-00001 TABLE 1 Percent by Starting material weight (%) Neutralizing Aluminum-EDTA 16.83 agents complex having a pKa of 5.87 Sodium  8.33 glutamate monohydrate Color Methyl red  0.00036 indicators Thymol blue  0.0019 Solvent Water the remainder being composed of water

[0081] The decontamination composition 1 is free of salts H.sub.aX.sub.b as defined according to the present invention.

[0082] Neutralization Test

[0083] A neutralization test was carried out with the following liquids: 1 M sodium hydroxide (NaOH) and 1 M hydrochloric acid (HCl), using the composition prepared in example 1, according to the following procedure:

[0084] to 1 mL of 1 M sodium hydroxide (NaOH) or 1 mL of 1 M hydrochloric acid (HCl) were successively added:

[0085] 1 mL, 2 mL, 3 mL, 4 mL, 5 mL, 10 mL, 20 mL, 30 mL, 40 mL and/or 50 mL of the solution from example 1, waiting a maximum of 1 minute between each addition, and the pH was measured after each addition.

[0086] The results are presented in table 2 and depicted in FIG. 1.

TABLE-US-00002 TABLE 2 Volume of Volume of ‘example 1’ ‘example 1’ solution added to solution added to 1 mL of 1M NaOH 1 mL of 1M HCl (mL) pH (mL) pH 0 13.17 0 −0.18 1 12.81 1 3.8 2 9.81 2 5.58 3 9.48 3 6.01 4 9.28 4 6.24 5 9.12 5 6.4 10 8.63 10 6.83 20 8.17 20 7.14 30 7.94 30 7.25 40 7.85 40 7.3 50 7.78 50 7.34

[0087] Color Test

[0088] A color test was carried out with the following liquids: 1 M sodium hydroxide (NaOH) and 1 M hydrochloric acid (HCl), using the composition prepared in example 1, according to the following procedure:

[0089] into a beaker containing 20 mL of solution from example 1 are added 10 mL of 1 M sodium hydroxide (NaOH) or of 1 M hydrochloric acid (HCl). The color is observed with the naked eye.

[0090] A variation in the color of the solution from example 1 as a function of pH is observed.

[0091] The results are presented in table 3 below.

TABLE-US-00003 TABLE 3 pH Observed color 3 Red 7 Yellow 12 Blue

[0092] Binding of Fluoride Ions Test

[0093] A binding of fluoride ions test was carried out with a 1 M solution of ammonium fluoride (NH.sub.4F), using the composition prepared in example 1, according to the following procedure:

[0094] to 5 mL of a 1 M solution of ammonium fluoride (NH.sub.4F) were successively added 1 mL or 5 mL of the solution from example 1, waiting a maximum of 1 minute between each addition, and the concentration of free fluoride ions was measured continuously.

[0095] The fluoride ion concentration is measured with a PHM240 ion meter sold by the company Radiometer and an Orion™ brand electrode specific for fluoride ions sold by the company Thermo Scientific.

[0096] The results are depicted in FIG. 2.

Example 2

[0097] A decontamination composition 2 was prepared that comprised:

TABLE-US-00004 TABLE 4 Starting material Percent by weight (%) Neutralizing Aluminum-EDTA complex 16.04 agents having a pKa of 5.87 L-Arginine 12.86 monohydrochloride Color indicator Thymol blue  0.004 Solvent Water the remainder being composed of water

[0098] The decontamination composition 2 is free of salts H.sub.aX.sub.b as defined according to the present invention.

[0099] Neutralization Test

[0100] A neutralization test was carried out according to the procedure from example 1 using the composition from example 2.

[0101] The results are presented in table 5 and depicted in FIG. 3.

TABLE-US-00005 TABLE 5 Volume of Volume of ‘example 2’ ‘example 2’ solution added to solution added to 1 mL of 1M NaOH 1 mL of 1M HCl (mL) pH (mL) pH 0 13.52 0 0.25 1 9.58 1 2.48 2 9.03 2 3.65 3 8.78 3 5.12 4 8.65 4 5.56 5 8.52 5 5.78 10 8.19 10 6.31 15 8.02 20 6.68 20 7.9 30 6.84 30 776 40 6.89 40 7.67 50 6.95 50 7.59

[0102] Color Test

[0103] A color test was carried out according to the procedure from example 1 using the composition from example 2.

[0104] A variation in the color of the solution from example 2 as a function of pH is observed.

[0105] The results are presented in table 6 below.

TABLE-US-00006 TABLE 6 pH Observed color 1 Red 7 Orange 12 Blue

[0106] Binding of Fluoride Ions Test

[0107] A binding of fluoride ions test was carried out according to the procedure from example 1 using the composition from example 2.

[0108] The results are depicted in FIG. 4.

Example 3

[0109] A decontamination composition 3 was prepared that comprised:

TABLE-US-00007 TABLE 7 Starting material Percent by weight (%) Neutralizing Aluminum-EDTA complex 10.9 agents having a pKa of 5.87 L-Lysine hydrochloride 49.58 Color Ethyl orange  0.002 indicators Bromophenol blue  0.002 Solvent Water the remainder being composed of water

[0110] The decontamination composition 3 is free of salts H.sub.aX.sub.b as defined according to the present invention.

[0111] Neutralization Test

[0112] A neutralization test was carried out according to the procedure from example 1 using the composition from example 3.

[0113] The results are presented in table 8 and depicted in FIG. 5.

TABLE-US-00008 TABLE 8 Volume of Volume of ‘example 3’ ‘example 3’ solution added to solution added to 1 mL of 1M NaOH 1 mL of 1M HCl (mL) pH (mL) pH 0 13.26 0 −0.17 1 9.33 1 2.16 2 8.93 2 3.04 3 8.73 3 3.61 4 8.58 4 4.32 5 8.48 5 5.05 10 8.15 10 5.93 20 7.84 20 6.39 30 7.69 30 6.58 40 7.52 40 6.68 50 7.46 50 6.74 60 7.4 60 6.79

[0114] Color Test

[0115] A color test was carried out according to the procedure from example 1 using the composition from example 3. A variation in the color of the solution from example 3 as a function of pH is observed. The results are presented in table 9 below.

[0116] Color Test

[0117] A color test was carried out according to the procedure from example 1 using the composition from example 3.

[0118] A variation in the color of the solution from example 3 as a function of pH is observed.

[0119] The results are presented in table 9 below.

TABLE-US-00009 TABLE 9 pH Observed color 3 Orange 7 Purple 12 Gray

[0120] Binding of Fluoride Ions Test

[0121] A binding of fluoride ions test was carried out according to the procedure from example 1 using the composition from example 3.

[0122] The results are depicted in FIG. 6.

[0123] In conclusion, decontamination compositions 1 to 3 neutralize 1 M sodium hydroxide and 1 M hydrochloric acid by restoring the pH to between 5.5 and 9. This variation in pH is accompanied by a change in color.

[0124] Decontamination compositions 1 to 3 also make it possible to bind fluoride ions by restoring the concentration of free fluoride ions to an acceptable value, that is to say a value of less than 1.5 mg/L.