FR2800291A1 - COMPOSITION AND PROCESS FOR THE DESTRUCTION OF ORGANOPHOSPHORUS AND / OR ORGANOSULFUR POLLUTANTS - Google Patents

Abstract

The invention concerns the use of an acid selected among the C2-C4 percarboxylic acids for decontaminating materials soiled by organophosphorous and/or organosulphurous compounds. The percarboxylic acid is in particular in the form of an anhydrous or substantially anhydrous organic solution of said percarboxylic acid, such as is obtained by reacting an aqueous hydrogen peroxide solution with the corresponding carboxylic acid miscible in water, in the presence of a catalyst and an organic solvent optionally the one whereby water has been continuously eliminated from the reaction medium by azeotropic distillation.

Description

i

  COMPOSITION AND METHOD FOR THE DESTRUCTION OF POLLUTANTS

  ORGANOPHOSPHORUS AND / OR ORGANO-SULFUR

  The present invention relates to the decontamination of fragile materials contaminated with toxic agents such as organophosphorus compounds and organosulfur compounds without causing significant degradation of said materials. It relates in particular to a new decontamination agent as well as to a composition and a method for destroying these organophosphorus pollutants and / or

organosulfur.

  The invention applies more particularly to the treatment of fragile materials contaminated with organophosphorus compounds, such as organophosphates, amidophosphates, organoamidophosphates, phosphorothionates, phosphonothionates and phosphonoamidothionates used in the field of agriculture as insecticides and pesticides , as well as by organosulfur compounds of the RS-R 'type, R and R' representing in particular hydrocarbon radicals and

  halogenated hydrocarbon radicals.

  Among the most well-known organophosphorus compounds, compounds such as O, O-diethyl-O-p-nitrophenyl phosphate (Paraoxon), O, O-diethyl-O-pnitrophenyl

  phosphonothioate (Parathion) and O, O-diethyl-

  O- (2-isopropyl-4-methyl-6-pyrimidyl) -phosphorothioate (Diazinon) play a big role in agriculture as

insecticides or as pesticides.

  Furthermore, toxic organosulfur compounds, such as 2-dichloro-2'-2'-diethyl sulfide or 2-phenyl-2-chlorodiethyl sulfide are also very aggressive chemical agents whose stability allows them to persist on a ground contaminated for several years,

  without experiencing a significant decrease in toxicity.

  It is therefore important to be able to have, in the case of intentional or accidental use of such compounds, a decontaminating composition capable of being able to decontaminate the materials quickly and effectively.

  contaminated with toxic agents.

  The most effective compositions currently available in the decontamination technique are solutions of sodium hydroxide in aqueous medium or in methylglycol in the presence of amine, or of calcium hypochlorite; however, such solutions are corrosive to fragile materials and in particular alloys

of light metals.

  It is well known that nucleophilic compounds are effective products for eliminating toxic agents from the organophosphate and organosulfur series. Thus, the hydroxyl anion in a strongly medium

  basic is able to neutralize these toxic agents.

  However, the efficiency obtained is accompanied by a strong

  aggressiveness towards the materials to be decontaminated.

  Another way is to use peroxygenated compounds such as hydrogen peroxide, tert-butyl hydroperoxide, perborates and peracids, in an environment that is not very basic, or even close to neutrality.

  their properties both nucleophilic and oxidizing.

  The various peroxygen compounds are used in solutions containing surfactants of the quaternary ammonium type, improving the contact between the peroxygen reagent and the toxic agent during decontamination. The peroxides currently proposed in the decontamination of materials soiled with the various families of toxic agents, in particular Paraoxon and sulfur compounds, are in the form of aqueous solutions of linear peracids with a long carbon chain, pH included between 6 and 8, or aqueous solutions based on industrial peracids such as magnesium monoperoxyphthalate or phthalimidoperhexanoic acid, these peracids

  being, in both cases, associated with surfactants

  active, in particular of the quaternary ammonium salt type.

  However, the first peracids are not commercially available and exhibit poor stability and solubility, and the second peracids, although commercially available, are in solid form at room temperature, exhibit poor stability at high temperature and do not are not easy to handle

for their implementation.

  There therefore remains a real need to be able to have decontaminating solutions with greater stability and easier handling than the aforementioned peracids, in order to allow total destruction and

  instant toxic agents on fragile materials.

  The Applicant has now discovered that C2 to C4 percarboxylic acids allow

achieve the desired result.

  The present invention therefore firstly relates to the use of an acid chosen from C2 to C4 percarboxylic acids in the decontamination of materials soiled with organophosphorus and / or organosulfur compounds. Advantageously, the percarboxylic acid used is in the form of an anhydrous or substantially anhydrous organic solution of said percarboxylic acid, as it was obtained by reaction of an aqueous solution of hydrogen peroxide with the corresponding carboxylic acid miscible with water, in the presence of a catalyst and an organic solvent, including one which has enabled continuous elimination by azeotropic distillation of water from the reaction medium. Such a preparation process and improved embodiments thereof are described in French patent applications Nos. 2,464,947 and 2,519,634 and in the European patent application.

EP-A-454,397.

  Such anhydrous or substantially anhydrous solutions are water-soluble liquids, which allows easier implementation of decontaminating solutions. The preferred percarboxylic acid is the acid

  perpropionic, due to its very high stability.

  In particular, the anhydrous or substantially anhydrous organic solution of perpropionic acid which can be used comprises perpropionic acid, as product, propionic acid as unreacted reagent, ethyl propionate as solvent, hydrogen peroxide as unreacted reagent, sulfuric acid or boric acid as catalyst, and dipicolinic acid as stabilizer of the peracid solution produced. The present invention also relates to a composition which can be used for the decontamination of materials soiled with organophosphorus and / or organosulfur compounds, this composition being characterized by the fact that it consists of an aqueous solution based on

  of at least one C2 to C4 percarboxylic acid.

  The percarboxylic acid (s), in particular perpropionic acid, have advantageously been introduced into said composition in the form of an anhydrous or substantially anhydrous organic solution of said acid

  percarboxylic, as indicated above.

  The percarboxylic acid (s) are present in the aqueous solution at a concentration for example of

3.78 x 10-4 at 0.15 mol / l.

  Furthermore, preferably, the aqueous solution is buffered at a pH between 7 and 10, in particular at a pH between 9 and 10. In general, the buffers

  usable are commercial solutions of pH 7 to 10.

  For example, pH 9 is obtained from an aqueous solution containing a mixture of boric acid (0.05 mole / l), potassium chloride (0.05 mole / l) and

  sodium hydroxide (0.022 mole / l).

  In accordance with a particularly preferred embodiment of the invention, the aqueous decontaminating composition also comprises at least one agent

cationic surfactant.

  The cationic surfactant (s) are advantageously of the quaternary ammonium type, being in particular represented by the formula (I): R1 R2 je_ e

R2 - N - R4 X (I)

  1 3 R in which: - Ri, R2 and R3, identical or different, each represent a C1-C4 alkyl group or a C1-C4 hydroxyalkyl group; - R4 represents a benzyl group or a linear or branched C11-C18 alkyl group; and - X represents a halogen or a hydroxyl radical, or by the formula (II): R

I

  CH2-CH2-N-CH2-CH2-N-CH2-CH2 xi (II) in which: - R represents a linear C16 alkyl group; and

- X1 represents a halogen.

  Examples of surfactants are: - cetyl trimethyl ammonium bromide; - cetyl trimethyl ammonium chloride; - cetyl dimethyl hydroxy-2 ethyl ammonium bromide; - cetyl methyl bis (2-hydroxyethyl) ammonium bromide; - benzyl trimethyl ammonium bromide; and - cetyl diaza-1,4-bicyclo [2.2.2] octyl ammonium bromide. These surfactants are known and, for the most part, commercially available. They can be prepared by the methods described by C.A. Bunton et al., J. Am. Chem. Soc., 95, 2912 (1973) and by L. Horner et al.,

  Phosphorus and Sulfur, 11, 339 (1981).

  The surfactant (s) are present in the aqueous decontaminating composition, in particular at

  10-3 to 0.1 mole per liter of composition.

  The present invention also relates to a process for decontaminating materials soiled with organophosphorus and / or organosulfur compounds, characterized in that the composition as defined above is applied to the soiled material, by spraying, spraying or simple washing, or soaking said soiled material in a tank containing the composition

as defined above.

  The molar ratio of C2 to C4 percarboxylic acid with respect to the pollutant is generally from 5 to 10 for organophosphorus pollutants (hydrolysis to phosphate) or from 3 to 5 for organosulfur pollutants (oxidation to sulfone). Contaminated fragile materials include electronic circuits (resin, electronic components, soldering), light alloys, polymers (poly (methyl methacrylate)), etc. These materials have been polluted by deposition of the toxic on the surface:

  therefore decontamination in heterogeneous phase.

  The tests carried out show a high efficiency of the compositions of the invention for the decontamination of toxic agents, such as Paraoxon

  and 2-phenyl-2'-chlorodiethyl sulfide.

  The use of the composition containing C2 to C4 percarboxylic acid, in particular perpropionic acid, in combination with the surfactant of the quaternary ammonium type allows practically instantaneous degradation of the toxic compounds.

  organophosphorus and organosulfur.

  The major advantages of the invention are that the composition exhibits excellent stability over time at high temperatures, unlike conventional compositions based on peracids, and that the C2 to C4 percarboxylic acid is in the form of a liquid soluble in water, which has an advantage during the use of the composition and which makes it possible to obtain the degradation of the abovementioned toxic agents, in particular the total degradation of the 2phenyl-2'-chlorodiethyl sulfide in its non-toxic sulfone form, which is not the case with the other organic peracids which are only available in solid form and which have a low solubility in the aqueous phase. The following Examples illustrate the present invention without, however, limiting its scope. In these Examples, the percentages are by weight unless otherwise indicated. EXAMPLE 1 Degradation of O, Odiethyl-Op-nitrophenyl phosphate (Paraoxon) An anhydrous solution of perpropionic acid was used having the following composition: Perpropionic acid ....... 17.1% Propionic acid .... ...... 22.2% Ethyl propionate ........ 59.5% Hydrogen peroxide ............... 1% Sulfuric acid ... ........ 0.05% Dipicolinic acid ........ 0.08% which had been prepared according to the method described in French patent application FR-A-2,519,634 but with the

ethyl propionate as solvent.

  Various organic solutions buffered at pH 9 or 10 were prepared from the above-mentioned anhydrous solution alone or with various surfactants (as reported in Table 1 below), the perpropionic acid being at the concentration of 3.78 x 10-4 mole / l and the agents

  surfactants, at a concentration of 10-3 mol / l.

  These different solutions were made to act on C on the Paraoxon at the concentration of

3.78 x 10-5 mole / liter.

  The degradation of Paraoxon was monitored at 25 ° C. according to a technique using UV-visible spectrometry at the wavelength of 402 nm,

  corresponding to the maximum absorption of the p-nitro- ion

  phenate released. The half-reaction times (in seconds) are

  shown in Table 1 below.

Table 1

  Time of surfactant half reaction (s) pH 9 pH 10

417,280

  Cetyl trimethyl ammonium bromide 170 135 Cetyl dimethyl 2hydroxyethyl ammonium bromide 156 145 Cetyl methyl bis (2-hydroxy ethyl) ammonium bromide 160 114 Cetyl diazo-1,4-bicyclo bromide [2.2.2] octyl ammonium 270 145 cetyl trimethyl ammonium 114 125 Benzyl trimethyl ammonium bromide 325 265 These results show that the destruction of Paraoxon by solutions of perpropionic acid is

  a quick and efficient response. In the presence of tensio-

  active of the quaternary ammonium type, the destruction rates of Paraoxon are high and quite

remarkable.

  EXAMPLE 2 Degradation of 2-phenyl-2'-sulfide

  chlorodiethyl The same anhydrous acid solution was used

perpropionic as in Example 1.

  Various aqueous solutions buffered to pH 7 or 9 were prepared from the above-mentioned anhydrous solution alone or with the surfactant cetyl trimethyl ammonium chloride, perpropionic acid being at the

  concentration of 15 x 10-2 mole / liter and the surfactant

  active, at a concentration of 10-3 mol / l.

  These different solutions were made to act at 25 ° C. on 2phenyl-2'-chlorodiethyl sulfide with

concentration of 5 x 10-2 mole / 1.

  The progress of the chemical destruction reaction of 2phenyl-2'-chlorodiethyl sulfide is determined by an analysis by gas chromatography, consisting of taking samples over time, analyzed by chromatography after addition of a

  mineral reducer (sodium thiosulfate).

  The half-reaction times (in seconds) are

  shown in Table 2 below.

  Table 2 Half-reaction time Surfactant (s) pH 7 pH 9

-_ 25 45

  Cetyl trimethyl chloride <15 <15 ammonium Benzyl trimethyl bromide 24 31 ammonium Table 2 indicates that the destruction of 2-phenyl-2'-chlorodiethyl sulfide by perpropionic acid takes place quickly, thus confirming the exceptional properties of perpropionic acid in the

  decontamination of toxic agents.

  The various examples above thus demonstrate the effectiveness of the decontaminating solutions of the present invention in the destruction of the various classes of toxic organophosphorus and organosulfur compounds.

Claims (13)

  1 - Use of an acid chosen from C2 to C4 percarboxylic acids in the decontamination of materials soiled with organophosphorus and / or organosulfur compounds. 2 - Use according to claim 1, characterized in that the percarboxylic acid is in the form of an anhydrous or substantially anhydrous organic solution of said percarboxylic acid, as it was obtained by reaction of an aqueous solution of hydrogen peroxide with the corresponding carboxylic acid miscible with water, in the presence of a catalyst and an organic solvent including optionally that which has allowed the continuous elimination by azeotropic distillation of water from the reaction medium.   3 - Use according to one of claims 1   and 2, characterized in that the percarboxylic acid is perpropionic acid.   4 - Use according to claims 2 and 3   taken simultaneously, characterized in that the anhydrous or substantially anhydrous organic solution of perpropionic acid comprises perpropionic acid, as product, propionic acid as unreacted reagent, ethyl propionate as solvent , hydrogen peroxide as unreacted reagent, sulfuric acid or boric acid as catalyst, and dipicolinic acid as solution stabilizer peracid manufactured.   - Composition usable for the decontamination of materials soiled with organophosphorus and / or organosulfur compounds, characterized in that it consists of an aqueous solution based on at least one C2 to C4 percarboxylic acid.   6 - Composition according to claim 5, characterized in that the percarboxylic acid (s) have been introduced into the composition in the form of an anhydrous or substantially anhydrous organic solution of said percarboxylic acid, as it was obtained by reaction d '' an aqueous solution of hydrogen peroxide with the corresponding carboxylic acid miscible with water, in the presence of a catalyst and an organic solvent including optionally that which has allowed the continuous elimination by azeotropic distillation of water from the reaction medium.   7 - Composition according to one of claims 5   and 6, characterized in that the percarboxylic acid is perpropionic acid.   8 - Composition according to Claims 6 and 7   taken simultaneously, characterized in that the percarboxylic acid has been introduced into the composition in the form of an anhydrous or substantially anhydrous organic solution, comprising perpropionic acid, as product, propionic acid as reagent n ' unreacted ethyl propionate as solvent, hydrogen peroxide as unreacted reagent, sulfuric or boric acid as catalyst, and dipicolinic acid as solution stabilizer peracid manufactured.   9 - Composition according to one of claims 5   to 8, characterized in that the percarboxylic acid (s) are present in the aqueous solution to   a concentration of 3.78 x 10-4 at 0.15 mol / l.   - Composition according to one of claims 5   to 9, characterized in that the aqueous solution is   buffered at a pH between 7 and 10.   11 - Composition according to claim 10, characterized in that the aqueous solution is   buffered at a pH between 9 and 10.   12 - Composition according to one of claims 5   to 11, characterized in that it also includes   minus a cationic surfactant.   13 - Composition according to claim 12, characterized in that the cationic surfactant (s) are of the quaternary ammonium type, being in particular represented by the formula (I): Ri le e R2 - N - R4 X (I) R   in which: - R1, R2 and R3, identical or different, each represent a C1-C4 alkyl group or a C1-C4 hydroxyalkyl group; - R4 represents a benzyl group or a linear or branched C1-C18 alkyl group; and - X represents a halogen or a hydroxyl radical, or by the formula (II): R CH2 -CH2-N-CH2-CH2-N-CH2-CH2 x (II) l 2l- -   in which: - R represents a linear C16 alkyl group; and - X1 represents a halogen.   14 - Composition according to claim 13, characterized in that the surfactant (s) are chosen from: - cetyl trimethyl ammonium bromide; - cetyl trimethyl ammonium chloride; - cetyl dimethyl hydroxy-2 ethyl ammonium bromide; - cetyl methyl bis (2-hydroxyethyl) ammonium bromide; - benzyl trimethyl ammonium bromide; and - cetyl diaza-1,4-bicyclo [2.2.2] octyl ammonium bromide.   15 - Composition according to one of claims 12   to 14, characterized in that the surfactant (s) are present at a rate of 10-3 to 0.1 mole per liter decomposition.   16 - Process for decontamination of materials soiled with organophosphorus and / or organosulfur compounds, characterized in that the composition as defined in one is applied to the soiled material   of claims 5 to 15, by spraying, spraying or   simple washing, or soaking said soiled material in a tank containing the composition such as   defined in one of claims 5 to 15.