FR2791968A1 - Process for the on-site production of ultra-pure hydrogen peroxide for the electronics industry, involves the use of an organometallic complex of cobalt and the reduction of oxygen in an acidic medium - Google Patents

Abstract

The hydrogen peroxide is obtained by the oxidation of a cobalt (II) complex in an acidic medium, the organic ligand being a polyazabicylo(6,6,6)eicosane and the installation being on-site and coupled with an additional purification unit if necessary. The process comprises the stages : (a) reduction of dioxygen in an acid medium with an organometallic complex on an inert support which is capable of being oxidized; and (b) separation of the oxidized complex obtained from the formed hydrogen peroxide by solid/liquid extraction; An Independent claim is also included for the installation by which the process is carried out.

Description

This patent application relates to a novel method of

  preparation of hydrogen peroxide. Today, the most common

  widely used, is a chemical process based on the oxidation of anthraquinone (Walton JH, J. Am Chem Soc. (1932), 54, 3228; Filson GW et al., US 2,059,569), commonly referred to as "AO method. ". This synthesis is carried out according to the following reaction scheme: OH OH X catalyst -R

+ 02 - <+ H202

  The alkyl anthraquinone solution, generally 2-ethyl anthraquinone, is hydrogenated in the presence of a catalyst (Pd on Al 2 O 3) in a water-immiscible organic solvent. The hydroquinone obtained is then oxidized by the dioxygen of the air to a mixture of hydroxy hydroperoxides, which are decomposed into hydrogen peroxide and the starting alkyl anthraquinone.

  which is recycled. The hydrogen peroxide formed is separated from the gold phase

  by extraction with water, the concentration of H2O2 being able to reach

  47% by weight; the aqueous solution is concentrated by distillation in order to obtain

  the various business solutions. The main disadvantages of this method are related to its hazards, the regeneration of the solution and the high costs of operation and maintenance of the process. Attempts have been made to replace the catalytic hydrogenation of anthraquinone by chemical reduction on sodium amalgam (Lynn S. et al., GB 1, 154,096 and US 3,351,104), or

  more recently by electrochemical reduction (Keita B. et al., J. Electro

  nal. Chem. 1983, 145, 431-437; Schmid lin-Houissoud, A. Thesis of the Univer-

  Geneva, 1997). However, none of these methods are industrial

  satisfactory. Also known are processes for the production of

  hydrogen oxide electrochemically. The first of them is

  on the electrolysis of sulfuric acid (Meindinger A., Ann Chem Chem Pharm Lieb.

  1853, 88, 57; Bunsen R. W., Pogg. Ann. 1854, 91, 621; Berthelot, M.CR 1878, 86, 71). Another is based on the reduction of the two-electron dioxygen (Pascal P., in New Treaty of Mineral Chemistry, Masson et Cie: 1960 Vol Volume XIII, 469-596, Tarasevich M. et al, in Comprehensive Treatise of Electrochemistry, Plenum Press: New York, 1983, Vol 7, Divisek J. et al, J.

  Electroanal. Chem. 1975, 65, 603), is carried out in an acidic medium (Dam.

  Janovic A. et al., J. Electrochem. Soc. 1967, 114, 466-472 and J. Electroanal.

  Chem. 1967, 15, 163-172; Genshaw M.A. et al. J. Electroanal. Chem. 1967, 163-172; Taylor R. J. et al., J. Electroanal. Chem. 1975, 64, 85-94.and J. Electroanal. Chem. 1975, 64, 95-105; Otsuka K. et al, Electrochim. Acta 1990, 319-322) or in a basic medium (Paliteiro et al., J. Electroanal Chem., 1987, 233, 147-159, Morcos I. et al., Electrochim Acta 1970, 15, 953-975; ZW et al., Proc., Electrochem Soc., 1984, 84, 158-178;

  ai, Pure Appl. Chem. 1957, 7, 69-76; Kalu E. E. et al. J. Appl. Electrochem.

  1990, 20, 932-940; Oloman C. et al., J. Appl. Electrochem. 1979, 9, 117123; Stucki S. CH 4,455,203 1984; Kornienko G. V. and ai, Russian J. Appl. Chem. 1996, 69, 229-231; Tatapudi P. et al., J. Electrochem. Soc. 1993, 140, 55-57; Taylor R. J. et al., J. Electroanal. Chem. 1975, 64, 63-84). Although in the middle

  the most promising results have been obtained, the instability of hydrogen peroxide (Duke FRJ Phys Chem 1961, 65, 304) and the delicate nature of its extraction have not made it possible to transpose the results30 observed in the laboratory, on an industrial scale. Finally, if the production of

  Hydrogen oxide by electrocatalysis appears more and more efficient, the fragility of the various electrodes used remains, to date, a poorly controlled parameter (Deronzier AJ, Chem Phys Phys Phys Chim Biol 1996, 93, 611- 619;

  Vork F.T.A., Electrochim. Acta 1990, 35, 135; Degrand C. J., Electroanal.

  Chem. 1984, 169, 259-268; Grangaard D.H., US 3,454,477 1969; Kang C. et al., J. Electroanal. Chem. 1996, 413, 165-174). Given the increasing applications of hydrogen peroxide, particularly in the field of the electronics industry, it is interesting to be able to produce hydrogen peroxide

  directly on its place of use. However, because of the costs of

  In fact, the installation of a production unit operating with the anthraquinone process is not profitable for an annual production of less than 20 000 tonnes and it also has several major drawbacks, such as environmental degradation. reaction and safety issues. The Applicant has therefore sought another method of manufacturing hydrogen peroxide, which can be implemented on site, with low maintenance costs, while leading to a solution of high purity hydrogen peroxide. She found that a process for the production of

  hydrogen peroxide by chemical means, using organomechanical complexes

  the problems mentioned above. It is

  why the subject of the invention is a process for the preparation of hydrogen peroxide

  which comprises the following steps:

  a) a step of reducing the dioxygen in an acid medium with a compound

  supported organometallic plexe capable of being oxidized, and b) a step of separating the supported organometallic complex and

  resulting from step a) and hydrogen peroxide, by

lide / liquid.

  The implementation of step a) requires the use of complexes

  ganometallic compounds whose metal cation is likely to oxidize in half

  acidic site, into a metal cation having a higher degree of oxidation.

  The implementation of step b) requires that the organomechanical complex

  The aqueous solution is adsorbed on an inert solid matrix and then reduced to form the active complex. As an inert carrier, there may be mentioned, for example, resins

  cationic resins, such as DOWEXTM resin (50WX2-400),

  killed from a polystyrene skeleton functionalized with sulfonic groups. The reduction is carried out by passing an aqueous solution containing a chemical reductant such as sodium tetrahydroboride (NaBH4). After washing the material with water, it is brought into contact with a solution

  aqueous acid containing oxygen, thus causing the formation and ex-

  simultaneous pulling of hydrogen peroxide. A water immiscible solution can be used to oxygenate the organometallic complex; the water

  formed oxygen is then extracted by a small amount of water.

  thode makes it possible to obtain more concentrated solutions of hydrogen peroxide.

gene.

  According to a first particular embodiment of the present invention, the

  The organometallic plex implemented in step a) is a complex of cobalt in the oxidation state (+11). In this case, the formation of hydrogen peroxide in step a) results from the activation of the oxygen by the cobalt ion of the immobilized organometallic complex involved, according to the following reaction: 2 [LCo] 2 + O 2 + 2H +> 2 [LCo] 3+ + H202

  A molecule of oxygen reacts in an acidic medium with two molecules.

  cobalt active complex (+11), to release a molecule of hydrogen peroxide and two molecules of cobalt complex in the oxidation state

(111).

  According to a second particular embodiment of the present invention, the organic ligand of the organometallic complex is a polyazamacrocycle, and more particularly a polyazabicyclo [6.6.6] eicosane, such as, for example, 1,3,6,8,10,13, 16,19-octaazabicyclo [6.6.6] eicosane (or sepulecrate) or its mono- or poly-substituted derivatives on one of the ring atoms, or 3,6,10,13,16,19-hexaazabicyclo [6.6.6 ] eicosane, or its mono or poly substituted derivatives on one of the ring atoms. By way of non-limiting examples of organometallic complexes, mention may be made of those described in the publications

  following: Sargeson A.M., Pure Appl. Chem. 1984, 56, 1603-1619; Botto-

  mley G.A. et al., J. Chem. 1994, 47, 143-179; Geue R. J. et al., J. Am. Chem. Soc. 1984, 106, 5478-5488; Creaser I. I. et al., J. Am. Chem. Soc. 1984, 106, 5729-5731, and in particular the complexes of formulas (1), (2) and (3) below:

N CH <R

  (HNH NHIN N, H NH Ni NHNH CZtco2C) Co2 + C Co2 + 9

NH NH N H NHNHN

l (N '' lCH RJ

(1) (2) (3)

  The following publications can also be cited: Behm C.A. et al., J. Chem. Soc., Chem. Common 1993, 1844-1846 and. Austr. J. Chem. 1995, 48, 1009-1030, in which sarcophagine complexes are described.

  substituted by long carbon chains [compounds of formula (3)].

  According to a particular variant of the process which is the subject of the present invention,

  The immobilized cobalt (+111) complex resulting from steps a) and b) is reduced to a cobalt (+11) complex. The formation of the active complex of cobalt (+11) can result from a reduction, either chemical or electrochemical, of the cobalt complex in the oxidation state (+111). According to a particular mode

  of the process as described above, it therefore comprises the three

following weights:

  a) a step of producing hydrogen peroxide chemically

than,

  b) a step of separating the formed hydrogen peroxide and the

oxidized plex, and

  c) a step of regenerating the active complex by chemical reduction;

  that, which is then reused in step a).

  Figure 1 illustrates the reaction cycle described above.

  According to another aspect of the present invention, the subject of the present invention is a plant for producing hydrogen peroxide using the method as described above. Such an installation comprises: an oxygenation compartment in which the hydrogen peroxide production reaction is carried out, an extraction compartment in which the hydrogen peroxide and the oxidized organometallic complex are separated, and

  a regeneration compartment in which the regeneration is carried out

  ration of the initial supported organometallic complex.

  The present invention also relates to an ultra pure hydrogen peroxide production plant, characterized in that it comprises downstream of

  the unit for producing hydrogen peroxide as defined above

  a purification unit for hydrogen peroxide, and especially

  an installation, as defined above, characterized in that

  that it is located on the site of use of the solution of hydrogen peroxide

  gene thus produced and if necessary thus purified, and more particularly on

  a production site of electronic components. As a purification plant

  for example, those employing one of the processes described in international publications WO 98/54085, WO 98/54086,

WO 98/54087 and WO 98/54088.

  The following examples illustrate the invention without limiting it.

  A-Synthesis and Main Characteristics of Complexes A-1- Principle a) Complex [(Sep) Co] CI3

  The method of synthesis used is a modification of that

  in the following publications: Creaser I. I. et al., J. Am. Chem. Soc. 1977, 99, 3181-3182 and. J. Am. Chem. Soc. 1982, 104, 6016-6025. Perchlorate ions are no longer used and purification of the complex is done without the use of ion exchange resin. The complex is isolated by simple precipitation in ethanolic medium, with a yield of 79%. The compound Co (Sep) 3+ is therefore synthesized very easily and in large quantities from the triethylenediamine complex of cobalt (III) in the presence of ammonia and formaldehyde according to the following reaction:

H2 H2 H2 (

N N N NH NH.

C CN ND HCHO, NH3 CN (Co3 N)

N N NH NH NH

H2H2 H2

  b) Fixing the complex on a solid support The [(Sep) Co] C13 complex is fixed by simple contact with a solution

  containing it, with a DOWEXM (50WX2-400) sulfonic resin.

  The chemical reaction involved is represented by the following equation: R 3 SO 3 H + [(Sep) Co] Cl 3> [(Sep) Co] CI 3 (R-SO 3 H) 3

  A material comprising 1.17 mmoles per gram of complex is obtained.

  The material obtained is stable since the desorption of the organomechanical complex

  only by means of a solution of hydrochloric acid

  concentrated to a minimum of 3 mol. I- '.

  c) Chemical reduction of the complex [(Sep) Co13 + After fixing the cobalt complex (III) on the solid support, it is reduced by passing over the material, an aqueous solution containing excess% of sodium tetrahydroboride. Immediate discolouration of the material is observed, which is then washed with water to remove traces of the reducing agent A-2-Procedures a) Synthesis of (Sep) CoCI3

N 73+

Nil NH

NHNHNH

(Co), 3CI '

NH NH NH

  To a suspension containing 23 g (0.31 mol) of lithium carbonate and 18.2 g (0.05 mol) of triethylenediamine cobalt (III) chloride complex in 125 ml of water are added simultaneously, drop by drop. , 166 ml (2.5 mol) of ammonia (27% solution in water) diluted in 380 ml of water and

  563 ml (7.5 mol) of formaldehyde (37% solution in water). After 2 hours

  At room temperature, the mixture is filtered and the pH of the filtrate is adjusted to 2 by addition of concentrated hydrochloric acid. The solution is then extended with 4 liters of ethanol and the mixture is then kept at 5 ° C. for 24 hours. After filtration, the precipitate obtained is dissolved in a minimum of water at 60 ° C., then 300 ml of acetone are rapidly added with vigorous stirring. The expected compound is isolated by filtration with a yield

of78% (m = 17.6g).

  1 H NMR (D 2 O) b (DPPm): 3.1 (m, 12H, N-CH 2 -CH 2 -N); 4.0 (dd, 12H,

N-CH2-N).

  1H NMR (D 2 O) δ (ppm): 56.04; 69.63.

  Centesimal analysis for CoC12H3oN8CI_3:

  Calculated: C% 31.9; H, 6.7; N% 24.8.

found: C% 31.6; H% 6.9; N% 24.7.

  b) Fixation of the Complex on a DowexM 50 X2-400 Resin An aqueous solution of 0.1 Mole / I [(Sep) Co] CI3 is eluted on a Dowex ™ 50 X2-400 cationic resin until saturation. After washing with water and then with ethanol, the orange powder obtained is dried under reduced pressure. The material analysis highlights a concentration of 1.17

mmoles of complex per gram.

  A-3-Electrochemical Characteristics a) Oxidation-reduction Potential The cyclic voltammogram of the complex [(Sep) Co] 3+ in KCl (0.1 mol.1 ') is shown in FIG. 2 (solvent: water + 0.2 mol. KCI working electrode: glassy carbon, v = 100mV.s- '). It consists of a single reversible wave at -0.574 V, attributable to the oxidation-reduction of the [(Sep) Co] 3+ '[(Sep) Co] 2+ couple. After several successive cycles, the intensity of the signals, whose ratio ij / ic is equal to 1, remains unchanged, showing that the pair [(Sep) Co] 3I / [(Sep) Co] 2+ is totally reversible. The nature of the associated anion

  complex and the pH of the solution have little influence on the

  electronic properties of the complex and modify very little

  cative the redox potential of the pair [(Sep) Co] 3 + / [(Sep) Co] 2+.

  b) Stability of the Sepulchrate Complex A stability study of the Sepulchrate complex was carried out; we

  notes that this compound has exceptional stability since

  this degradation is noticeable in a very acidic medium (HCI 12 M) or very low

  (pH> 12). Only the formation of a hydroxylamine function has been demonstrated when the complex is brought into the presence of concentrated hydrogen peroxide in a strongly basic medium. However, this evolution is not problematic, since it takes place only in conditions far from

  those which are implemented in the process.

  c) Physicochemical data of complex [(SeP) CoCl3 Solvent UV-visible E112 (LCO (III) / LCo (II)) (V vs. ECS) (nm) [H (mole · l.cm3 ')] HCl (1 mol.l ') 344 (116); 474 (106) -0.589 (d) Activation of dioxyene with the Co (Sep) 2+ complex in aqueous phase The reduction of dioxygen into hydrogen peroxide by the cobalt (II) complex is carried out in a two-fold mechanism main stages (1) and (2)

  and one of whose intermediates is a molecule of hydrogen superoxide.

  Since step (2) is much faster, the excess of oxygen in the reaction medium is therefore not an annoying parameter. In addition, the reaction between the hydrogen peroxide formed and the cobalt complex molecules in the +11 oxidation state which have not yet reacted with the oxygen proves to be a secondary reaction for the process. It is therefore necessary to have a report

  [02] / [H202] as high as possible to minimize this parasitic reaction.

  [LCo] 2+ + 02 + H +> [LCo] 3+ + HO2 (1) [LCo] 2+ + HO2 + H +> [LCo] 3+ + H202 (2) 2 [LCo] 2+ + H202> 2 [LCO] 3+ + 2 OH (3) A-4-Summary Table of Results

  Solid phase - CoCI3 complex (Sep) adsorbed on DOWEX 50X2 resin

  - Grafting rate: 1.7 mmol of complex per gram of material Liquid phase - aqueous solution of HCl (0.1 mol / l) saturated with oxygen

([02] = 1.3 mmol / l).

  Regeneration of - Instant chemical reduction by passage of a solution

aqueous NaBH4 complex.

  Stability of the material - Solid inert (complex unchanged after 5 cycles) solid Results - Yield greater than 75% when the dioxygen contribution

is enough.

  It has the advantage of a stable material thode fast cycle (formation and extraction of instantaneous and simultaneous H202, rapid regeneration)

  During the test carried out, it was possible to verify that the aqueous solution of

  hydrogen oxide obtained by the process which is the subject of the present invention

  contained any of the metal impurities contaminating the solutions

  according to the anthraquinone method, namely in particular the aluminum ions

  minium, tin or iron. This process therefore makes it possible to limit the number and the

  subsequent purification steps.

Claims (9)

  A process for the preparation of hydrogen peroxide comprising the following steps: a) a step of reducing the dioxygen in an acid medium with an organometallic complex supported on an inert material, capable of being oxidized, and   b) a step of separation of the oxy-organometallic complex   resulting from step a) and hydrogen peroxide by lide / liquid.   2. The method as defined in claim 1, wherein the   organometallic plex implemented in step a) is a complex of cobalt in the oxidation state (+11)   3. Method as defined in one of claims 1 or 2, in which   the organic ligand of the organometallic complex is a polyazamide   macrocycle, and more particularly a polyaza-bicylo [6.6.6] eicosane.   4. The process as defined in claim 3, wherein the ligand   organic organometallic complex is 1,3,6,8,10,13,16,19 octaaza-   bicyclo [6.6.6] eicosane (or sepulcrate).   5. Method as defined in one of claims 2 to 4, in   which the cobalt complex (+111) resulting from steps a) and b), is reduced in cobalt complex (+11).   6. A process as defined in one of claims 1 to 5, characterized   in that it comprises the following three steps: a) a step of producing hydrogen peroxide by chemical means, b) a step of separating the formed hydrogen peroxide and the oxidized complex, and   (c) a step of regeneration by chemical reduction, of   active plex, which is then reused in step a).   7. Hydrogen Peroxide Production Facility for Implementation   method as defined in one of claims 1 to 6, characterized by in that it includes:   an oxygenation compartment in which the reaction is carried out   action of production of hydrogen peroxide,   - an extraction compartment in which are separated the   hydrogen oxide and the oxidized organometallic complex, and a regeneration compartment in which the   regeneration of the initial supported organometallic complex.   8. Installation as defined in claim 7, characterized in that it furthermore a purification unit for hydrogen peroxide, situated   downstream of the production unit of said peroxide.   9. Installation as defined in one of claims 7 or 8,   characterized in that it is located on the site of use of the solution of hydrogen peroxide thus produced and, if necessary, thus purified, and more   in particular, on a production site of electronic components.