PROCESS FOR MANUFACTURING A SUBSTITUTED CYCLOHEXANECARBONITRILE

Abstract

A process for manufacturing a substituted cyclohexanecarbonitrile said process comprising the following steps: —reacting the corresponding substituted cyclohexanecarboxylic acid with thionyl chloride to make the corresponding acyl chloride; and simultaneously or subsequently —reacting the chloride with sulfonamide in sulfolane as solvent to make the substituted cyclohexanecarbonitrile.

Claims

1-15. (canceled)

16. A process for manufacturing a substituted cyclohexanecarbonitrile said process comprising the following steps: reacting the corresponding substituted cyclohexanecarboxylic acid with thionyl chloride to make the corresponding acyl chloride; and simultaneously or subsequently reacting the chloride with sulfonamide in sulfolane as solvent to make the substituted cyclohexanecarbonitrile.

17. The process according to claim 16, wherein the substituted cyclohexanecarboxylic acid is obtained by hydrogenating one of the corresponding substituted cyclohexenecarboxylic acids with hydrogen gas in the presence of a hydrogenation catalyst.

18. The process according to claim 17, wherein the catalyst is PtO2 and wherein the hydrogenation takes place in glacial acetic acid as solvent.

19. The process according to claim 17, wherein the substituted cyclohexenecarboxylic acid is obtained by cyclization of the corresponding linear acid in the presence of a catalyst.

20. The process according to claim 19, wherein the linear acid is geranic acid, the catalyst is phosphoric acid in toluene and the resulting substituted cyclohexanecarbonitrile is 2,2,6-trimethylcyclohexanecarbonitrile (C10A).

21. The process according to claim 17, wherein the substituted cyclohexenecarboxylic acid is obtained by a Diels-Alder reaction between a conjugated diene and an unsaturated carboxylic acid in the presence of a Lewis acid catalyst.

22. The process according to claim 21, wherein: the conjugated diene is 2,4-dimethylpenta-1,3-diene, the unsaturated carboxylic acid is methacrylic acid, the Lewis acid catalyst is BoB(Ac)4, THF is used as solvent and the resulting substituted cyclohexanecarbonitrile is 1,2,2,4-tetramethylcyclohexylcarbonitrile (C11B) eventually comprising its 1,3,3,5 isomer; or the conjugated diene is 2,4-dimethylpenta-1,3-diene, the unsaturated carboxylic acid is crotonic acid, the Lewis acid catalyst is BoB(Ac)4, THF is used as solvent and the desired resulting substituted cyclohexanecarbonitrile is 2,2,4,6-tetramethylcyclohexylcarbonitrile (C11C) eventually comprising its 2,3,3,5 isomer; or the conjugated diene is 2,3-dimethylbuta-1,3-diene, the unsaturated carboxylic acid is tiglic acid, the Lewis acid catalyst is BoB(Ac)4, THF is used as solvent and the resulting substituted cyclohexanecarbonitrile is one of the stereoisomers of 1,2,4,5-tetramethylcyclohexanecarbonitrile (C11D); or the conjugated diene is 2,3-dimethylbuta-1,3-diene, the unsaturated carboxylic acid is angelic acid, the Lewis acid catalyst is BoB(Ac)4, THF is used as solvent and the resulting substituted cyclohexanecarbonitrile is another stereoisomer of 1,2,4,5-tetramethylcyclohexenecarbonitrile (C11E); or the conjugated diene is 2,4-dimethylpenta-1,3-diene, the unsaturated carboxylic acid is tiglic acid, the Lewis acid catalyst is BoB(Ac)4, THF is used as solvent and the resulting substituted cyclohexenecarbonitrile is 1,2,3,3,5-pentamethylcyclohexanecarbonitrile (C12A).

23. The process according to claim 16, wherein the substituted cyclohexanecarboxylic acid is obtained by hydrolysing the corresponding substituted cyclohexane ester, which substituted cyclohexane ester is obtained by hydrogenating the corresponding substituted cyclohexene ester with hydrogen gas in the presence of a hydrogenation catalyst.

24. The process according to claim 23, wherein the substituted cyclohexane ester is ethyl 2,2,5,6-tetramethylcyclohexanecarboxylate, the substituted cyclohexene ester is ethyl 2,3,6,6-tetramethylcyclohex-2-enecarboxylate and the resulting substituted cyclohexanecarbonitrile is 2,2,5,6-tetramethylcyclohexanecarbonitrile (C11A).

25. The process according to claim 24, wherein the ethyl 2,3,6,6-tetramethylcyclohex-2-enecarboxylate is been obtained through the following reaction steps: a second order nucleophilic substitution reaction (SN2) on ethyl 3-oxo-2-methylbutanoate (so called 2-methylacetoacetate) with 1-chloro-3-methyl-2-butene in alkaline medium and the subsequent decarboxylation of the alpha-ketoacid to afford the compound 3,6-dimethylhept-5-en-2-one; a Horner-Wadsworth-Emmons (HWE) reaction on the obtained 3,6-dimethylhept-5-en-2-one with triethylphosphonoacetate and sodium hydride to form the corresponding ester ethyl 3,4,7-trimethylocta-2,6-dienoate; the cyclization of ethyl 3,4,7-trimethylocta-2,6-dienoate with a Lewis acid catalyst or with phosphoric acid in toluene to obtain ethyl 2,3,6,6-tetramethylcyclohex-2-enecarboxylate.

26. A substituted cyclohexanecarbonitriles obtainable by a process according to claim 16.

27. A substituted cyclohexanecarbonitrile having the formula C11A, C11B, C11C, C11D, C11E or C12A.

28. A process for manufacturing an aqueous hydrogen peroxide solution comprising the following steps: hydrogenating a working solution which comprises an alkylanthraquinone and/or tetrahydroalkylanthraquinone and a mixture of a non-polar organic solvent and a polar organic solvent; oxidizing the hydrogenated working solution to produce hydrogen peroxide; and isolating the hydrogen peroxide, wherein the polar organic solvent is the substituted cyclohexanecarbonitrile according to claim 26.

29. The process according to 28, said process having a production capacity of hydrogen peroxide of up to 100 kilo tons per year.

30. The process according to claim 28, said process being operated in a plant located at an industrial end user site.

Description

EXAMPLE 1: SYNTHESIS OF 2,2,6-TRIMETHYLCYCLOHEXANECARBONITRILE (C10A)

[0057] Step 1

[0058] To a 6 L double-jacketed reactor equipped with mechanical stirring, a condenser linked to nitrogen arrival, temperature probe and additional funnel were added toluene (3 L, 3 vol), geranic acid (1 Kg, 1030 mL, 5.05 mol, 1 eq.) and more toluene (1 L, 1 vol). The yellow solution was heated to 110° C. then H3PO4 (85% purity, 103.7 mL, 174.7 g, 1.52 mol, 0.3 eq) was added. The orange brown solution was then stirred at 110° C. for 6 h (NMR monitoring). The reaction mixture was cooled down to 20° C., and neutralized with brine solution (2 L containing 376 g of NaCl). After neutralization and decantation, the organic phase was washed with water (1 L), concentrated under reduced pressure to afford the final product as a white solid. In some cases, if there was too much starting material left, a slurry in hexane (2 vol) at rt (room temperature) followed by filtration gave the pure desired product as a white solid

[0059] 832 g of a white solid corresponding to the cyclohexenecarboxylic acid intermediate with a NMR purity (α, α, α-trifluorotoluene as internal standard) of 74% were obtained.

[0060] Step 2

[0061] In a 1 L double jacketed stainless steel hydrogenator equipped with H.sub.2 and N2 entry, a mechanical stirring and a condenser were added cyclohexene carboxylic acid intermediate (230 g, 1.35 mol, 1 eq.), PtO2 (3.11 g, 0.014 mol, 0.01 eq.) and acetic acid (604 g, 575 mL, 2.5 vol.). The reaction mixture was stirred at rt, and Continuous H2 flow (1 bar) was sent to the reactor for 1h. The mixture was then heated to 50° C. for one more hour. The reaction mixture was then cooled to 20° C. and concentrated under vacuum to afford the desired product as colorless oil which crystallized to white solid with time.

[0062] 240 g of colorless oil which crystallized to white solid with time, corresponding to cyclohexane carboxylic acid intermediate with a NMR purity (trifluorotoluene as standard) of 88.8% were obtained.

[0063] Step 3

[0064] In a 3 L double jacketed reactor under nitrogen equipped with a mechanical stirring, an introduction pump and a condenser connected to a scrubber filled with NaOH 15%, cyclohexane carboxylic acid intermediate (500.60 g, 2.94 mol, 1 eq.) was added. The product was heated to 50° C. then SOCl2 (371 g, 227 mL, 3.08 mol, 1.05 eq.) was added dropwise by the pump over one hour, while HCl is degazed and trapped by the scrubber. The reaction mixture was stirred at 80° C. for one hour, and then heated to 130° C. while sulfolan (568 g, 450 mL, 0.9 vol.) was added to the mixture. In parallel, in another 1 L double jacketed reactor, a solution of sulfamide (342 g, 3.52 mol, 1.2 eq.) in sulfolane (1388 g, 1100 mL, 2.2 vol.) was prepared and heated at 50° C. This solution is then added dropwise via an addition pump to the reaction mixture at 130° C. over one hour. The mixture was stirred at 130° C. for 2h then cooled to 20° C. and quenched with NaOH 20% solution (764 g, 3.82 mol, 1.3 eq.). In a 6 L reactor the mixture was diluted with water (750 g) and extracted three times with a mixture hexane/MTBE 3/2 (3*1000 mL). The combined organic phases were washed with water three times (3*1400 g) and concentrated under vacuum to afford a dark orange liquid (388 g, 83.9% yield). The crudes of three cyanation batches were purified together by vacuum distillation (90° C., 10 mbar) to afford the pure desired product.

[0065] 830 g of a colorless liquid corresponding to the C10A solvent (2,2,6-trimethylcyclohexanecarbonitrile (C10A)) with a GC purity (area) superior to 99% with its isomers were obtained.

EXAMPLE 2: SYNTHESIS OF 2,2,5,6-TETRAMETHYLCYCLOHEXANE-1-CARBONITRILE (C11A)

[0066] Step 1

[0067] In a 10 L reactor, 2-methylacetoacetate (3.2 mol: 455 g) is diluted in absolute ethanol (3.5 L) before adding sodium ethanolate (1.05 equivalents: 224 g) over a period of 30 minutes under an inert atmosphere. The reaction medium is then stirred mechanically for 1 h at 25° C. before being cooled to −10° C. A solution of 1-chloro-3-methyl-2-butene (1.05 equivalents: 104.5 g) diluted in 1 L of absolute ethanol is added. The reaction medium is brought to ambient temperature and is stirred overnight. The reaction medium is filtered through celite and concentrated under reduced pressure, yielding ethyl 2-acetyl-2,5-dimethylhex-4-enoate, isolated in the form of a yellow oil (yield: quantitative).

[0068] Step 2

[0069] In a 10 L reactor, 47% aqueous potassium hydroxide solution (2 L) is diluted with water (2 L) and ethanol (2 L). Ethyl 2-acetyl-2,5-dimethylhex-4-enoate (2.8 mol: 600 g) is added, and the reaction mixture is refluxed for 6 h. After cooling, the reaction medium is diluted with cyclohexane (2 L) and an 18% sodium chloride solution (2 L) is added. The aqueous phase is extracted with cyclohexane (2 L), and the combined organic phases are successively washed with a solution of 18% NaCl (2 L), a solution of 3.5% HCl (500 mL) to reach a pH of 7 dried over magnesium sulphate, filtered and concentrated under reduced pressure. The crude reaction product is finally purified by distillation under reduced pressure (15 bar, 65° C.), resulting in isolated 3,6-dimethylhept-5-en-2-one in the form of a colorless oil (yield over 2 steps: 60%).

[0070] Step 3

[0071] In a 10 L reactor, triethylphosphonoacetate (1.1 equivalents: 423 g) is diluted in THF (3.5 L). The solution is cooled to −10° C. before adding 60% NaH diluted in oil (1.2 equivalents: 83 g) over a period of 30 minutes. A solution of 3,6-dimethylhept-5-en-2-one 1 (1.7 mol: 240 g) diluted in THF (300 mL) is added and the reaction medium is brought to room temperature and mechanically stirred overnight. A solution of 18% NaCl (2 L) and cyclohexane (2 L) is added to the reaction medium. The aqueous phase is extracted with cyclohexane (1 L), and the combined organic phases are successively washed with 18% NaCl solution, dried over magnesium sulfate, filtered and concentrated under reduced pressure. The crude reaction medium is finally purified by flash chromatography on silica gel (eluent: cyclohexane/MTBE 100%.fwdarw.93-7%) to produce, after evaporation under reduced pressure, (Z/E) ethyl 3,4,7-trimethylocta-2,6-dienoate which is isolated as a yellow oil (yield: 84%); the product has been characterized by proton NMR

[0072] Step 4

[0073] In a 10 L reactor, boron trifluoride etherate (1.27 equivalents: 416 g) is diluted in toluene (3 L). A solution of ethyl (Z/E) ethyl 3,4,7-trimethylocta-2,6-dienoate (2.3 mol: 486 g) diluted in toluene (1 L) is added. The reaction medium is heated at 50° C. for 2 h before being quenched with iced water in another 101 reactor. Toluene (500 ml) used to clean the first reactor is added to the reaction medium. A solution of 18% NaCl (500 mL) and MTBE (500 mL) is added to make the reaction medium less turbid, as well as toluene (500 mL). The aqueous phase is separated, and the organic phase is washed with 18% NaCl solution (1.5 L). The combined aqueous phases are extracted with MTBE (500 mL), and the combined organic phases are successively washed with 26% NaCl solution (3 L), dried over magnesium sulfate, filtered and concentrated under reduced pressure. The crude reaction product is finally purified by distillation under reduced pressure (3 mbar, 75-77° C.), yielding ethyl 2,3,6,6-tetramethylcyclohex-2-ene-1-carboxylate isolated in the form of a colorless oil (yield: 91%); the product has been characterized by proton NMR and mass spectrometry.

[0074] Step 5

[0075] In a 1 L autoclave, platinum dioxide (0.04 equivalents: 5 g) is added to ethyl 2,3,6,6-tetramethylcyclohex-2-ene-1-carboxylate (0.52 mol: 110 g) diluted in acetic acid (500 mL). The reaction medium is put under a constant pressure of 11 bar H2 for 8 h, filtered and concentrated under reduced pressure. The solution is then diluted in MTBE (150 mL) and successively washed with water (50 mL), a 26% NaCl solution (2×50 mL), dried over magnesium sulfate and concentrated under reduced pressure to yield ethyl 2,5,6-tetramethylcyclohexane-1-carb oxylate isolated as a colorless oil (yield: 93%); the product has been characterized by proton NMR.

[0076] Step 6

[0077] In a 1 L autoclave, potassium hydroxide (5.2 equivalents: 185.5 g) is added to a solution of ethyl 2,2,5,6-tetramethylcyclohexane-1-carboxylate (0.64 mol: 135 g) diluted in methanol (400 mL). The reaction medium is heated to 175° C. (˜14 bar) and stirred for 6h30. The reaction medium is concentrated under reduced pressure before dissolving the sodium hydroxide in water (75 ml). Iced water is added to the medium and acidified by adding 36% HCl. The aqueous phase is extracted with ethyl acetate (2×250 mL), and the combined organic phases are successively washed with 26% NaCl solution (100 mL), dried over magnesium sulphate and concentrated under reduced pressure, resulting in 2,2,5,6-tetramethylcyclohexane-1-carboxylic acid isolated as a yellow oil (yield: 97%); the product has been characterized by proton IR spectroscopy and mass spectrometry

[0078] Step 7

[0079] In a 1 L flask, thionyl chloride (1.24 equivalents: 187.6 g) is added to 2,2,5,6-tetramethylcyclohexanecarboxylic acid (1.27 mol: 234 g).). The reaction medium, equipped with a scrubber, is stirred for one hour before being refluxed for another hour. After cooling, the reaction medium is concentrated under reduced pressure to evaporate the excess thionyl chloride. The crude reaction medium is finally purified by distillation under reduced pressure (145 mbar, 163° C.) resulting in 2,2,5,6-tetramethylcyclohexanecarbamoyl chloride isolated in the form of a colorless oil (yield: 90%); the product has been characterized by proton NMR and mass spectrometry

[0080] Step 8

[0081] In a 1 L flask, the sulfonamide (1.2 equivalents: 85.5 g) is added to the 2,2,5,6-tetramethylcyclohexane-1-carbonyl chloride (0.74 mol: 150 g) diluted in the sulfolane (400 mL) under an inert atmosphere. The reaction medium is heated at 180° C. with mechanical stirring for 3 h before being quenched with 0.7 M sodium hydroxide (3.5 L) and brine (26% sodium chloride solution) (300 ml) is added. The aqueous phase is extracted with hexane-MTBE (3:2) (5×500 ml), and the combined organic phases are successively washed with water (4×1 L), dried over magnesium sulphate and concentrated under reduced pressure. The crude reaction medium is finally purified by distillation under reduced pressure (7 mbar, 86-87° C.), resulting in the isolated 2,2,5,6-tetramethylcyclohexane-1-carbonitrile C11A in the form of a colorless oil (yield: 87.degree. %). the product has been characterized by proton NMR and mass spectrometry

EXAMPLE 3: SYNTHESIS OF 2,2,5,6-TETRAMETHYLCYCLOHEXANECARBONITRILE (C11A)

[0082] Steps 1 to 6 are identical to those of Example 2 but steps 7 and 8 have been regrouped in a single one pot synthesis as follows:

[0083] In a 1 L flask, thionyl chloride (1.24 equivalents: 187.6 g) is added to 2,2,5,6-tetramethylcyclohexane-1-carboxylic acid (1.27 mol: 234 g).). The reaction medium, equipped with a scrubber, is stirred for one hour before being heated.

[0084] Then dilution with sulfolane (same concentration as in Example 2), introduction of sulfamide (same amount as in Example 2) and performing all reaction steps exactly as in Example 2. After concentration of the reaction medium, a liquid with a mass balance of 84% molar is obtained and its structure was confirmed by NMR analysis.

EXAMPLE 4: SYNTHESIS OF 1,2,2,4-TETRAMETHYLCYCLOHEXANECARBONITRILE (C11B)

[0085] Step 1: Diels-Alder Reaction

[0086] In a three-necked flask equipped with a mechanical stirrer and a condenser, 50 g of BoB(Ac)4 (182 mmol) and 147 g of methacrylic acid (1.7 mol) were introduced.

[0087] After dissolution, the medium was diluted with 600 ml of dry THF and 150 g of 2,4-dimethyl-1,3-pentadiene (1.56 mol) were added. The whole was heated at 60° C. during 16h and then, the solvent was evaporated under vacuum.

[0088] 500 ml of water were added to hydrolyze the catalyst (BoB(Ac)4), and then the aqueous phase was extracted with ethyl acetate (4×200 ml).

[0089] The organic phase was washed with 20 ml of a NaCl solution (26%) and then dried over magnesium sulfate and concentrated under vacuum.

[0090] 240 g of solid were obtained.

[0091] This solid was dissolved/suspended in 1 L of petroleum ether and brought to reflux.

[0092] Then it was allowed to cool to room temperature, and placed at 5° C. overnight to finish crystallization.

[0093] It was then filtered to obtain 170 g of 1,2,2,4-tetramethylcyclohex-3-enecarboxylic acid and its 1,3,3,5 isomer (in ratio 3/1) as proved by NMR analysis.

[0094] Step 2: Hydrogenation

[0095] In a 2 L jacketed reactor, 165 g of the 1,2,2,4-tetramethylcyclohex-3-enecarboxylic acid (0.9 moles) were introduced and then diluted with 800 ml of glacial acetic acid.

[0096] 10 g of platinum oxide were added and nitrogen was circulated to purge the atmosphere.

[0097] A slight overpressure (100 mbar) of H2 was then applied while stirring at 1500 RMP and monitoring the H2 consumption with a mass flow meter.

[0098] After 1.5h hydrogen consumption was no longer observed and thus the reactor was purged with nitrogen for 15 min.

[0099] The reaction medium was then filtered, the solvent evaporated, and the filter residue dissolved in 750 ml of ethyl acetate, the organic phase washed with 250 ml of water and 2×250 ml of 26% NaCl.

[0100] After drying, 158 g of oil was obtained, which was found to be 1,2,2,4-tetramethylcyclohexyl carboxylic acid and its 1,3,3,5 isomer (in ratio 3/1) by NMR analysis (no purification necessary).

[0101] Step 3: Chlorination

[0102] In a three-necked 1 L flask equipped with a thermocouple, a condenser and under an inert atmosphere, 150 g of 1,2,2,4-tetramethylcyclohexanecarboxylic acid were introduced and 1.2 equivalents (1.03 mol) of thionyl chloride were added. (143 g).

[0103] At the outlet of the condenser, a guard vessel under nitrogen followed by a trap (15% NaOH) was placed with stirring to trap the HCl released.

[0104] After a few minutes, an endotherm was observed (medium at 5° C.) with significant degassing.

[0105] The medium was then heated at about 75° C. (reflux of thionyl chloride) until slight reflux for one hour.

[0106] The product obtained was first distilled at atmospheric pressure to remove the remaining thionyl chloride, then the chloride(s) were isolated at 141° C./60 mbar. 151 g of slightly yellow liquid was obtained (yield 86% in 1,2,2,4- and 1,3,3,5-tetramethylcyclohexanecarbonyl chloride).

[0107] Step 4: Cyanation

[0108] In a two-necked 2 L flask with mechanical stirring and under an inert atmosphere, 125 g of sulfonamide (1.3 moles) were introduced.

[0109] Then, it was diluted with 1 L of sulfolane previously melted at 40° C.

[0110] 200 g of 1,2,2,4- and 1,3,3,5-tetramethylcyclohexanecarbonyl chloride (˜1 mole) were added while stirring for 30 min.

[0111] It was then heated at 140° C. for 4h (conversion followed by GC).

[0112] The medium was cooled and then poured into a solution of NaOH 100 g/5 L of water.

[0113] The organic phase was extracted in 4×1 of a cyclohexane/MTBE mixture (2/1).

[0114] The organic phases were combined, washed with 3×500 ml of water and 500 ml of 26% NaCl.

[0115] The crude reaction medium was dried over sulfate magnesium before being concentrated to give an oil (170 g) before distillation.

[0116] Distillation at 77-79° C./5 mBar gave 160 g of 1,2,2,4-tetramethylcyclohexanecarbonitrile (C11B) and its 1,3,3,5 isomer.

EXAMPLE 5: SOLUBILITY TESTS OF HYDROGENATED QUINONES IN DIFFERENT SOLVENT MIXTURES

[0117] The determination of the QH solubility was performed on synthetic EQ/ETQ working solutions. These quinones mixed in the tested solvents have been hydrogenated to a fixed level and cooled down successively to 3 different temperatures before the measurement (min. 3 hours to stabilize the system between each measurement). The conditions applied for these tests were:

TABLE-US-00001 EQ concentration 100 g/kg ETQ concentration 140 g/kg Polar solvent variable (*) Level of hydrogenation 10.8 Nl H2/kg WS (~116 g of QH/kg of WS or a TL (Test Level) of 16.3 g of H2O2/kg of WS (=maximum theoretical value of TL if all QH dissolved)) Temperature of 75° C. hydrogenation Temperatures of indicated in Table 1 as temperature precipitation at which QH is measured

[0118] (*) the polar solvents tested were sextate, decanenitrile, 2,2,6-trimethylcyclohexanecarbonitrile (C10A), 2,2,5,6-tetramethylcyclohexanecarbonitrile (C11A) and 1,2,2,4-tetramethylcyclohexylcarbonitrile (C11B). They were used in mixture with S-150 in the ratios indicated in Table 1, Table 1-2, Table 2 and FIG. 1 attached, which also shows the results obtained. In this Figure, Kb stands for the weight partition coefficient of hydrogen peroxide between the water and the working solution (mixture of quinones and organic solvents). It is calculated using the following formula:

Kb=(g H2O2/kg aqueous phase)/(g H2O2/kg organic phase)

[0119] The Tables and FIG. 1 demonstrate the very high potential of cyclohexanecarbonitrile structures versus linear nitriles like decanenitrile, and especially of solvents C11A and C11B which when used in a ratio of 77% and 70% respectively, even lead to complete solubility of the QH at 60° C. (and hence, to a TL of 16.3 as calculated above).

[0120] The maximum solubility of a hydrogenated quinone (QH) in a solvent mixture is directly correlated with the productivity of the working solution. The higher is the QH solubility, the higher will be the theoretical quantity of hydrogen peroxide achievable per kg of WS (Productivity). These theoretical values, designated by the terms “Test level (gH2O2/kg of WS) measured at . . . ” in Table 1, were calculated as follows:

[0121] 1 mole (240 g) ETQH (which actually is the QH in our Examples) per kg of WS will produce 1 mole (34 g) of H.sub.2O.sub.2 per kg of WS. Hence, the test level in our Examples equals: 34*QH/240.

[0122] Again, the values obtained with 2,2,6-trimethylcyclohexanecarbonitrile (C10A) are much higher (almost the double in fact) than with sextate or a linear nitrile like decanenitrile, and with solvent C11A, they even reach the absolute maximum theoretical value.

[0123] Table 2 attached also shows that solvents C11A and C11B are less soluble in H.sub.2O.sub.2 than solvent C10A (as indicated by the lower level of TOC in the H.sub.2O.sub.2 obtained), and hence allow reaching a higher purity level of the H2O2.

TABLE-US-00002 TABLE 1 2,2,6-trimethyl- 2,2,6-trimethyl- Methylcyclohexyl cyclohexane- cyclohexane- acetate Decanenitrile carbonitrile carbonitrile Solvant Sextate (40%) Decanenitrile (65%) 3MCH-CN (60%) 3MCH-CN (50%) Mass ratio of polar solvent in solvent % 40 35 60 50 Mass ratio of S150 in solvent % 60 65 40 50 Kb of the solvents mix 176 171 171 247 Approx density of polar solvents at amb T° (kg/l) 0.94 0.83 0.89 0.89 QH (g/kg) measured at . . . 50° C. 55° C. 60° C. 52 62.2 110 73.9 65° C. 60.8 71.5 full soluble 80.3 70° C. 68 78.6 full soluble full soluble Test level (gH2O2/kg) measured at . . . 50° C. 55° C. 60° C. 7.4 8.8 15.6 10.5 65° C. 8.6 10.1 full soluble 11.4 70° C. 9.6 11.1 full soluble full soluble 2,3,6,6-tetramethyl- 2,3,6,6-tetramethyl- cyclohexane- cyclohexane- carbonitrile carbonitrile Solvant 4MCH-CN (77%) 4MCH-CN (50%) Mass ratio of polar solvent in solvent % 77 50 Mass ratio of S150 in solvent % 23 50 Kb of the solvents mix 176 300 Approx density of polar solvents at amb T° (kg/l) 0.895 0.895 QH (g/kg) measured at . . . 50° C. 84.2 54.4 55° C. 90.5 60.4 60° C. full soluble 69.1 65° C. full soluble 75.9 70° C. full soluble 104.5 Test level (gH2O2/kg) measured at . . . 50° C. 11.9 7.7 55° C. 12.8 8.6 60° C. full soluble 9.8 65° C. full soluble 10.8 70° C. full soluble 14.8

TABLE-US-00003 TABLE 1-2 1,2,2,4 1,2,2,4 tetramethylcyclo tetramethylcyclo hexancarbonitrile hexancarbonitrile Solvant (C11B) (C11B) Mass ratio of polar % 70 52 solvent Mass ratio of S150 % 30 48 Partition coefficient of 176 300 solvent Kb QH (g/kg) measured 55° C. 109.4 66.6 at . . . 60° C. full soluble 76.4 65° C. full soluble 106.6 70° C. full soluble full soluble Test level (gH2O2/kg) 55° C. 15.5 9.4 measured at . . . 60° C. full soluble 10.8 65° C. full soluble 15.1 70° C. full soluble full soluble

TABLE-US-00004 TABLE 2 2,2,6-trimethylcyclohexane- 2,2,5,6-tetramethylcyclohexane- 1,2,2,4-tetramethylcyclohexane- carbonitrile (C10A) carbonitrile (C11A) carbonitrile (C11B) C10H17N C11H19N C11H19N Polar Solvesso H2O2 in TOC in H2O2 in TOC in H2O2 in TOC in solvent 150 OP H2O2 OP H2O2 OP H2O2 (%) (%) (g/kg) Kb Kc (ppm) (g/kg) Kb Kc (ppm) (g/kg) Kb Kc (ppm) 30 70 0.9821 538 928 0.919 575 281 40 60 1.466 360 1042 1.271 416 268 1.632 333 308 50 50 2.135 247 1248 0 0 269 2.487 217 328 60 40 3.08 171 1456 2.332 238 274 3.167 171 280 70 30 3.871 136 1684 2.786 199 291 3.805 142 290