CA1206741A - Process for producing non-aqueous hydrogen peroxide solutions - Google Patents
Process for producing non-aqueous hydrogen peroxide solutionsInfo
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- CA1206741A CA1206741A CA000449245A CA449245A CA1206741A CA 1206741 A CA1206741 A CA 1206741A CA 000449245 A CA000449245 A CA 000449245A CA 449245 A CA449245 A CA 449245A CA 1206741 A CA1206741 A CA 1206741A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B15/00—Peroxides; Peroxyhydrates; Peroxyacids or salts thereof; Superoxides; Ozonides
- C01B15/01—Hydrogen peroxide
- C01B15/013—Separation; Purification; Concentration
- C01B15/017—Anhydrous hydrogen peroxide; Anhydrous solutions or gaseous mixtures containing hydrogen peroxide
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Abstract
ABSTRACT OF THE DISCLOSURE
The production of hydrogen peroxide solutions extremely low in water in higher boiling solvents by mixing hydrogen perox-ide solutions in solvents whose azeotrope boiling points with wa-ter lie below the boiling point of hydrogen peroxide with higher boiling solvents which at best form azeotropes with water whose boiling points lie close to or above the boiling point of hydrg-gen peroxide. The mixture is then freed from water and from the lower boiling solvents by distillation. An in situ method for producing the above mixture is described.
The production of hydrogen peroxide solutions extremely low in water in higher boiling solvents by mixing hydrogen perox-ide solutions in solvents whose azeotrope boiling points with wa-ter lie below the boiling point of hydrogen peroxide with higher boiling solvents which at best form azeotropes with water whose boiling points lie close to or above the boiling point of hydrg-gen peroxide. The mixture is then freed from water and from the lower boiling solvents by distillation. An in situ method for producing the above mixture is described.
Description
6 ~
The present invention relates to a process for producing non-acqueous hydrogen peroxide solutions.
It is known that the water content of hydrogen peroxide solutions causes pxoblems in many reactions, for example, in oxi-dations or epoxidations (see, for example, Org. Reactions 7, 395 (1953).
Quite some time ago attempts were made to use correspon-ding organic solutions instead of pure aqueous solutions of hydro-gen peroxide.
However, difficulties were encountered in the production of these solutions. Aqueous solutions of hydrogen peroxide were usually used as the starting material for producing organic hydro-- gen peroxide solutions and either they were only mixed with the desired organic compound and subsequently dehydrated by distilla-tion or the aqueous solutions were extracted with the organic compound and, when required dehydrated.
In both cases orsanic solutions of hydrogen peroxide were actually obtained but their water content always was at approximatQly 1% by weight or higher (see, for example, German 20 Patents Nos. 2,038,319 and 2,038,320, US Patent No. 3 743 706 and British Patent No. 931,11g).
According to the processes of the German Patent Nos.
The present invention relates to a process for producing non-acqueous hydrogen peroxide solutions.
It is known that the water content of hydrogen peroxide solutions causes pxoblems in many reactions, for example, in oxi-dations or epoxidations (see, for example, Org. Reactions 7, 395 (1953).
Quite some time ago attempts were made to use correspon-ding organic solutions instead of pure aqueous solutions of hydro-gen peroxide.
However, difficulties were encountered in the production of these solutions. Aqueous solutions of hydrogen peroxide were usually used as the starting material for producing organic hydro-- gen peroxide solutions and either they were only mixed with the desired organic compound and subsequently dehydrated by distilla-tion or the aqueous solutions were extracted with the organic compound and, when required dehydrated.
In both cases orsanic solutions of hydrogen peroxide were actually obtained but their water content always was at approximatQly 1% by weight or higher (see, for example, German 20 Patents Nos. 2,038,319 and 2,038,320, US Patent No. 3 743 706 and British Patent No. 931,11g).
According to the processes of the German Patent Nos.
2,038,319 and 2,038,320 attempts were made to remove the water present in the organic solutions by distillation at reduced pres-sure or followed by azeotropic distillation with an additional entraining agent.
In the process of US Patent No. 3,743,706 the extracting agent itself was to be used as the entraining agent. However, details are lacking.
Also in British Patent No. 931,119 the participant in the mixture was used for azeotropically distilling off the water. How-ever, in the production of organic hydrogen peroxide solutions ~2~6~
from aqueous solutions a further s~bstantial disadvantage became evident in addition to the frequently two high water content.
During the removal of the water at the pressures applied in that case a specific percentage of hydrogen peroxide was en-trained with the distillate; i.e., between 0.5 and 0.6% by weight in the simulation test. Moreover, further losses due to decompo-sition were incurred at the bottom.
In the processes of German Patents Nos. 2,038,319 and 2,038,320 organic phosphorus compounds and heterocylic nitrogen compounds were us~d and in the processes of British Patent No.
931,119 and US Patent No. 3,743,706 aliphatic or cycloaliphatic esters were used. While in US Patent No. 3,743,706 no data on carrying out an azeotropic distillation are provided, in the pro-cesses of the other three patents pressure far below 100 mbars.
are used (see the examples).
In fact in the two German patents a pressure range is ~uite generally mentioned; it was below 400 mbars. However in the simulation of the process with triethyl phosphate and N-methyl pyrrolidone at pressures of 400 and 100 m bars respectively hydro-20 gen peroxide in amounts of 0.28 and 0.6% by weight and 0.26 and 0.8% by weight was found in the distillate, in both cases relative to the distillate. Furthermore, an additional loss of hydrogen peroxide was incurred, i.e., 7.5 and 4.1% by weight and 4.7 and
In the process of US Patent No. 3,743,706 the extracting agent itself was to be used as the entraining agent. However, details are lacking.
Also in British Patent No. 931,119 the participant in the mixture was used for azeotropically distilling off the water. How-ever, in the production of organic hydrogen peroxide solutions ~2~6~
from aqueous solutions a further s~bstantial disadvantage became evident in addition to the frequently two high water content.
During the removal of the water at the pressures applied in that case a specific percentage of hydrogen peroxide was en-trained with the distillate; i.e., between 0.5 and 0.6% by weight in the simulation test. Moreover, further losses due to decompo-sition were incurred at the bottom.
In the processes of German Patents Nos. 2,038,319 and 2,038,320 organic phosphorus compounds and heterocylic nitrogen compounds were us~d and in the processes of British Patent No.
931,119 and US Patent No. 3,743,706 aliphatic or cycloaliphatic esters were used. While in US Patent No. 3,743,706 no data on carrying out an azeotropic distillation are provided, in the pro-cesses of the other three patents pressure far below 100 mbars.
are used (see the examples).
In fact in the two German patents a pressure range is ~uite generally mentioned; it was below 400 mbars. However in the simulation of the process with triethyl phosphate and N-methyl pyrrolidone at pressures of 400 and 100 m bars respectively hydro-20 gen peroxide in amounts of 0.28 and 0.6% by weight and 0.26 and 0.8% by weight was found in the distillate, in both cases relative to the distillate. Furthermore, an additional loss of hydrogen peroxide was incurred, i.e., 7.5 and 4.1% by weight and 4.7 and
3.9~ by weight, relative to the hydrogen peroxide used. On adding up the amount of hydrogen peroxide removed with the distillate and the amount lost due to decomposition the total losses at a distilla-tion at 400 and 100 m bars respectively were at least 7 to 8% by weight of hydrogen peroxide used. However, when the distillation is carried out at substantially lower pressures, i.e., far below 100 m bars, then it is clear tha-t substantially higher amounts of hydrogen peroxide are in the distillate which can exceed one per-cent by wei~ht, relative to the distillate. However, at these ~2~t7~
pJeSsures which are assumed to be preferred the examples are carried out (see loc. cit.).
According to the prior art i-t seemed, therefore, that drying by distallation of organic hydrogen peroxide solutions produced with a solvent whose own boiling point or the boiling point of possible azeo-tropes is closed to or above the boiling point of hydrogen peroxide necessarily results in substantial losses of hydrogen peroxide when operating on a large industrial scale.
However, not only was the loss of -the hydrogen per-oxide a substantial disadvantage but the fact that the residues from distillation were not anhydrous by any means was another disadvantage.
Thus, for example, the phosphorus-organic solutions had residual wa-ter contents of between 0.97 and 9.5% by weight.
However, -these solutions are not really suitable for, e.g., hydroxylation processes. Even in the only example of the German Patent No. 2,038,320 the water con-tent was 11.4% by weight in -the organic phase.
It has also been proposed to produce practically anhydrous organic solutions of hydrogen peroxide by mixing them with carboxylic acid in such a way that the aqueous hydrogen peroxide solutions are brought into contact with a]kyl or cycloalkyl esters of saturated aliphatic carboxylic esters having a to-tal of 4 to 8 carbon atoms and forming azeotropes with water and that -the azeo-tropic dehydra-tion is carried out at pressures of between 160 and 1000 mbars, see applicant's German Offlegungsschrift No. 3,225,307 published January 12, 1984.
~674~
Organic solutions of hydrogen peroxide whose water content lies below 0.5% by weight are obtained in this manner.
Furthermore, practically no losses of hydrogen peroxide used are incurrent in their produc-tion.
~lowever, this process is restricted to the carboxylic - 3a -.~
:~2~
esters mentioned above, but it would be desirable to also have a process for producing similarly anhydrous .solutions of hydrogen peroxide in higher boiling organic solvents.
It has now been found that anhydrous solutions of hydro-gen peroxide in higher boiling organic solvents can be produced practically without loss of hydrogen peroxide used by producing solutions of hydrogen peroxide in higher boiling solvents having a water content of up to 1~ by weight, preferably below 0.5% by weight by mixing solutions of hydrogen peroxide in organic solv-ents forming one or several azeotropes with water whose boilingpoints lie below the boiling point of hydrogen peroxide, relative to standard pressure, with higher boiling organic solvents which form no azeotropes with water or only azeotropes which boil close to or above the boiling point of hydrogen peroxide, relative to standard pressure, and that the starting solutions of hydrogen peroxide in the solvents forming azeotropes with water whose azeotrope boiling points lie below the boiling point of hydrogen peroxide, relative to standard pressure, can also be formed while directly mixing aqueous hydrogen peroxide solutions with those azeotrope-forming solvents and the higher boiling solvents, where-upon the entire solvent which forms azeotropes with water whose azeotrope boiling lies below the boiling point of hydrogen perox-ide distilled off and an anhydrous solution of hydrogen peroxide in the corresponding higher boiling solvent is obtained.
By higher boiling organic solvents which form no azeo-tropes with water or only azeotropes whose boiling points at standard pressure are close to or above the boiling point of hydro-gen peroxide are meant on the one hand phosphorus compounds having the formula ~2~7~
Rl--(X)m~ (Z) p ( )n R2 wherein X, ~ and Z represent an 0-atom, or an N-(Cl-C8)-alkyl group or an N-(C4-C7)-cycloalkyl group, n, m and p represent the number 0 or 1 and Rl, R2 and R3 represent straight-chain or bran-ched Cl-C~-alkyl or C4-C6-cycloalkyl radicals which can be sub-stitu-ted, when required, by halogen, hydroxyl, Cl-C4-alkoxy, CN
or phenyl groups.
Primarily trialkyl phosphates with Cl-C8 groups, pre-ferably triethyl phosphate, are suitable ~or producing the organic solutions of hydrogen peroxide according to the present invention.
Even aromatie carboxylic esters having the structural formula R
R2 ~ C00 Rl wherein R represents the grouping CH3, C2H5, n-C3H7, i C3H7, 20 n-C4Hg, i-C4Cg, tert. C4Hg, see. C4Hg, R2 and R3 represent sub-stituents whieh are inert with respect to hydrogen peroxide such as H, Cl, F, alkyl such as Rl, CH30, C2H50, C00 R~R4=Rl) and R2 and R3 ean be in any position relative to C00 R grouping, are excellently suitable for the present invention. Thus, particularly phthalic esters, preferably phthalic diethyl ester, have been found to be very favourable.
Furthermore, carboxylic amides or lactams having the general formula (C 2)n C~O
R
wherein R represents a straight-ehain or branched Cl-C4-alkyl 6~d9L~
radical which can be substituted when required by halogen, hydr-oxyl or Cl-C3-alkyl radicals and n represents the number 2 to 5.
Very good results were attained here with N-alkyl pyrro-lidones with Cl-C4-alkyl groups, particularly with N-methyl pyrr-olidone.
It has also been found that tetra substituted ureas having the following formula can be used:
R~ / R
N - C - N
R4/ \ R2 wherein Rl, R2, ~3 and R4 represent Cl-C6-alkyl groups, ureas in which Rl, R2, R3 and R4 are identical to each other being prefer-ably used.
Tetramethyl, tetraethyl and tetrabutyl ureas have been found to be very good higher boiling solvents.
Hydrogen peroxide can be present in aqueous solutions of any concentration. Solutions containing from 3 to 90~ by weight of hydrogen peroxide, perferably from 30 to 85~ by weight, are best suited.
Conventional stabilizers, for example, those mentioned in ULLMANN, Enzyklopadie der technischen Chemie, Vol. 17, 4th Edition, page 709, can be used as stabilizers for hydrogen perox-ide.
Ethers such as dioxane, diisopropyl ether or methyl-tert.-butyl ether as well as dichloro methane and C5-C8-aliphatic hdyro-carbons are useful as organic solvents which form one or several azeotropes with water whose boiling points are below the boiling point of hydrogen peroxide at standard pressure.
However, preferred solvents of this type are alkyl or cycloalkyl esters of satruated aliphatic carboxylic acids which 6 _ ~6~
have a total of 4 to 8 carbon atoms, primarily acetic-n-propyl ester or acetic-i-propyl ester or acetic ethyl ester and also dichloro methane. The concentration of hydrogen peroxide in the aliphatic carboxylic esters is, for example, 3 to 60~ by weight.
In these low-boiling solvents hydrogen peroxide can be used in the dissolved form or, as described hereinbefore, the aqueous hydrogen peroxide solution is mixed with the low-boiling solvent and the high~boiling solvent, whereupon the azeotrope-forming low-boiling solvent is distilled off toge-ther with the water.
When the hydrogen peroxide is used as a solution in the low-boiling solvents described above, these solutions have a water content of maximally 1~ by weight, preferably below 0.5~ by weight.
The lower hoiling solvent is distilled off together with the possibly introduced water as the corresponding azeotrope at a pressure from 50 to 1000 mbars.
In each case the pressures to be used especially in this range vary with the higher boiling solvent applied.
The amount of the lower boiling solvent must be at least so rated that the water introduced, when required, can be distilled off as azeotrope with this solvent so that a solution of hydrogen peroxide can be obtained in the higher boiling solvent containing up to 1~ by weight, preferably below 0.5~ by weight of water.
This can easily be determined by a preliminary test.
Apart from using aqueous hydrogen peroxide solutions this possibly present water can also be entrained by the higher boiling solvent itself. Thus, when using organic hydrogen perox-ide solutions the higher boiling solvent need not be anhydrous.
The advantage of the process according to the present invention also lies in that the solutions according to the present invention, in the case that their water content should have increased by de-composition of the hydrogen peroxide can be azeotropically dehydrated again by a correspondingly dosed addition of the lower boiling sol~ent.
The hydrogen peroxide solution and the solvent are usu-ally mixed in mixing kettles preferably provided with stirring equipm~nt.
` The process according to the present invention can be carried out in conventional evaporators and distilling apparatuses, as for example, tower packing columns and tray columns.
Any material which is inert with respect to hydrogen peroxide, as for example, glass, enamel, aluminium, passivated refined steel, specific plastics, is a suitable material.
The advance in the art of the process according to the present invention lies in the safety of obtaining hydrogen perox-ide solutions in solvents which have higher boiling points than those of hydrogen peroxide but have a wa-ter content of only up to 1~ by weight, preferably even below 0.5% by weight. Furthermore, during the production of these solutions practically no loss of hydrogen peroxide applied is incurred~
The advantages also are the decisive differences as com-pared with the processes of DE-AS Nos. 2,462l957 and 2,462,900 in which hydrogen peroxide is jointly distilled off with the phenols or phenol ethers to be reacted from a mixture containing as the third component a solvent for hydrogen peroxide which has a boil-ing point higher than that of the phenol or phenol ethers. Accor-ding to the examples and according to DE-AS No. 2,410,742 and DE-AS No. 2,419,758 from which the above Auslegeschriften have been divided, preferred third components are trioctyl phosphates.
It is not described how the hydrogen peroxide solutions to be applied are produced in trioctyl phosphates. Therefore, it must be assumed that these solutions were produced in a manner 3Q ana logous to that described in German Patent No. 20 38 319 and, therefore, must have comparably high residual water contents. Of course, this residual water also changes into the vapour phase.
pJeSsures which are assumed to be preferred the examples are carried out (see loc. cit.).
According to the prior art i-t seemed, therefore, that drying by distallation of organic hydrogen peroxide solutions produced with a solvent whose own boiling point or the boiling point of possible azeo-tropes is closed to or above the boiling point of hydrogen peroxide necessarily results in substantial losses of hydrogen peroxide when operating on a large industrial scale.
However, not only was the loss of -the hydrogen per-oxide a substantial disadvantage but the fact that the residues from distillation were not anhydrous by any means was another disadvantage.
Thus, for example, the phosphorus-organic solutions had residual wa-ter contents of between 0.97 and 9.5% by weight.
However, -these solutions are not really suitable for, e.g., hydroxylation processes. Even in the only example of the German Patent No. 2,038,320 the water con-tent was 11.4% by weight in -the organic phase.
It has also been proposed to produce practically anhydrous organic solutions of hydrogen peroxide by mixing them with carboxylic acid in such a way that the aqueous hydrogen peroxide solutions are brought into contact with a]kyl or cycloalkyl esters of saturated aliphatic carboxylic esters having a to-tal of 4 to 8 carbon atoms and forming azeotropes with water and that -the azeo-tropic dehydra-tion is carried out at pressures of between 160 and 1000 mbars, see applicant's German Offlegungsschrift No. 3,225,307 published January 12, 1984.
~674~
Organic solutions of hydrogen peroxide whose water content lies below 0.5% by weight are obtained in this manner.
Furthermore, practically no losses of hydrogen peroxide used are incurrent in their produc-tion.
~lowever, this process is restricted to the carboxylic - 3a -.~
:~2~
esters mentioned above, but it would be desirable to also have a process for producing similarly anhydrous .solutions of hydrogen peroxide in higher boiling organic solvents.
It has now been found that anhydrous solutions of hydro-gen peroxide in higher boiling organic solvents can be produced practically without loss of hydrogen peroxide used by producing solutions of hydrogen peroxide in higher boiling solvents having a water content of up to 1~ by weight, preferably below 0.5% by weight by mixing solutions of hydrogen peroxide in organic solv-ents forming one or several azeotropes with water whose boilingpoints lie below the boiling point of hydrogen peroxide, relative to standard pressure, with higher boiling organic solvents which form no azeotropes with water or only azeotropes which boil close to or above the boiling point of hydrogen peroxide, relative to standard pressure, and that the starting solutions of hydrogen peroxide in the solvents forming azeotropes with water whose azeotrope boiling points lie below the boiling point of hydrogen peroxide, relative to standard pressure, can also be formed while directly mixing aqueous hydrogen peroxide solutions with those azeotrope-forming solvents and the higher boiling solvents, where-upon the entire solvent which forms azeotropes with water whose azeotrope boiling lies below the boiling point of hydrogen perox-ide distilled off and an anhydrous solution of hydrogen peroxide in the corresponding higher boiling solvent is obtained.
By higher boiling organic solvents which form no azeo-tropes with water or only azeotropes whose boiling points at standard pressure are close to or above the boiling point of hydro-gen peroxide are meant on the one hand phosphorus compounds having the formula ~2~7~
Rl--(X)m~ (Z) p ( )n R2 wherein X, ~ and Z represent an 0-atom, or an N-(Cl-C8)-alkyl group or an N-(C4-C7)-cycloalkyl group, n, m and p represent the number 0 or 1 and Rl, R2 and R3 represent straight-chain or bran-ched Cl-C~-alkyl or C4-C6-cycloalkyl radicals which can be sub-stitu-ted, when required, by halogen, hydroxyl, Cl-C4-alkoxy, CN
or phenyl groups.
Primarily trialkyl phosphates with Cl-C8 groups, pre-ferably triethyl phosphate, are suitable ~or producing the organic solutions of hydrogen peroxide according to the present invention.
Even aromatie carboxylic esters having the structural formula R
R2 ~ C00 Rl wherein R represents the grouping CH3, C2H5, n-C3H7, i C3H7, 20 n-C4Hg, i-C4Cg, tert. C4Hg, see. C4Hg, R2 and R3 represent sub-stituents whieh are inert with respect to hydrogen peroxide such as H, Cl, F, alkyl such as Rl, CH30, C2H50, C00 R~R4=Rl) and R2 and R3 ean be in any position relative to C00 R grouping, are excellently suitable for the present invention. Thus, particularly phthalic esters, preferably phthalic diethyl ester, have been found to be very favourable.
Furthermore, carboxylic amides or lactams having the general formula (C 2)n C~O
R
wherein R represents a straight-ehain or branched Cl-C4-alkyl 6~d9L~
radical which can be substituted when required by halogen, hydr-oxyl or Cl-C3-alkyl radicals and n represents the number 2 to 5.
Very good results were attained here with N-alkyl pyrro-lidones with Cl-C4-alkyl groups, particularly with N-methyl pyrr-olidone.
It has also been found that tetra substituted ureas having the following formula can be used:
R~ / R
N - C - N
R4/ \ R2 wherein Rl, R2, ~3 and R4 represent Cl-C6-alkyl groups, ureas in which Rl, R2, R3 and R4 are identical to each other being prefer-ably used.
Tetramethyl, tetraethyl and tetrabutyl ureas have been found to be very good higher boiling solvents.
Hydrogen peroxide can be present in aqueous solutions of any concentration. Solutions containing from 3 to 90~ by weight of hydrogen peroxide, perferably from 30 to 85~ by weight, are best suited.
Conventional stabilizers, for example, those mentioned in ULLMANN, Enzyklopadie der technischen Chemie, Vol. 17, 4th Edition, page 709, can be used as stabilizers for hydrogen perox-ide.
Ethers such as dioxane, diisopropyl ether or methyl-tert.-butyl ether as well as dichloro methane and C5-C8-aliphatic hdyro-carbons are useful as organic solvents which form one or several azeotropes with water whose boiling points are below the boiling point of hydrogen peroxide at standard pressure.
However, preferred solvents of this type are alkyl or cycloalkyl esters of satruated aliphatic carboxylic acids which 6 _ ~6~
have a total of 4 to 8 carbon atoms, primarily acetic-n-propyl ester or acetic-i-propyl ester or acetic ethyl ester and also dichloro methane. The concentration of hydrogen peroxide in the aliphatic carboxylic esters is, for example, 3 to 60~ by weight.
In these low-boiling solvents hydrogen peroxide can be used in the dissolved form or, as described hereinbefore, the aqueous hydrogen peroxide solution is mixed with the low-boiling solvent and the high~boiling solvent, whereupon the azeotrope-forming low-boiling solvent is distilled off toge-ther with the water.
When the hydrogen peroxide is used as a solution in the low-boiling solvents described above, these solutions have a water content of maximally 1~ by weight, preferably below 0.5~ by weight.
The lower hoiling solvent is distilled off together with the possibly introduced water as the corresponding azeotrope at a pressure from 50 to 1000 mbars.
In each case the pressures to be used especially in this range vary with the higher boiling solvent applied.
The amount of the lower boiling solvent must be at least so rated that the water introduced, when required, can be distilled off as azeotrope with this solvent so that a solution of hydrogen peroxide can be obtained in the higher boiling solvent containing up to 1~ by weight, preferably below 0.5~ by weight of water.
This can easily be determined by a preliminary test.
Apart from using aqueous hydrogen peroxide solutions this possibly present water can also be entrained by the higher boiling solvent itself. Thus, when using organic hydrogen perox-ide solutions the higher boiling solvent need not be anhydrous.
The advantage of the process according to the present invention also lies in that the solutions according to the present invention, in the case that their water content should have increased by de-composition of the hydrogen peroxide can be azeotropically dehydrated again by a correspondingly dosed addition of the lower boiling sol~ent.
The hydrogen peroxide solution and the solvent are usu-ally mixed in mixing kettles preferably provided with stirring equipm~nt.
` The process according to the present invention can be carried out in conventional evaporators and distilling apparatuses, as for example, tower packing columns and tray columns.
Any material which is inert with respect to hydrogen peroxide, as for example, glass, enamel, aluminium, passivated refined steel, specific plastics, is a suitable material.
The advance in the art of the process according to the present invention lies in the safety of obtaining hydrogen perox-ide solutions in solvents which have higher boiling points than those of hydrogen peroxide but have a wa-ter content of only up to 1~ by weight, preferably even below 0.5% by weight. Furthermore, during the production of these solutions practically no loss of hydrogen peroxide applied is incurred~
The advantages also are the decisive differences as com-pared with the processes of DE-AS Nos. 2,462l957 and 2,462,900 in which hydrogen peroxide is jointly distilled off with the phenols or phenol ethers to be reacted from a mixture containing as the third component a solvent for hydrogen peroxide which has a boil-ing point higher than that of the phenol or phenol ethers. Accor-ding to the examples and according to DE-AS No. 2,410,742 and DE-AS No. 2,419,758 from which the above Auslegeschriften have been divided, preferred third components are trioctyl phosphates.
It is not described how the hydrogen peroxide solutions to be applied are produced in trioctyl phosphates. Therefore, it must be assumed that these solutions were produced in a manner 3Q ana logous to that described in German Patent No. 20 38 319 and, therefore, must have comparably high residual water contents. Of course, this residual water also changes into the vapour phase.
4~1~
Furthermore, the production of the anhydrous solutions of hydrogen peroxide in phenols or phenol ethers according to DE-AS Nos. 2,462,957 and 2,462,990 requires a high expenditure of energy because of the total evaporation of the phenol component together with the hydrogen peroxide.
At the same time safety problems are encountered due to the common presence of hydorgen peroxide and of the organic compo-nents in the vapour phase, quite apart from the losses of hydrogen peroxide due to the distillation.
As compared therewith, the process according to the pre-sent invention produces the anhydrous solutions which are obtained as a bottom product and not as a top product without any lower boiling entraining agent.
The present invention will be described by way of the following Examples.
Example _ 420O0 g of triethyl phosphate are added to 421 g of a 42.74% by weight solution of hydrogen peroxide in acetic-isopropyl ester (= 179.9 g of H2O2) having a residual water content of 0.03 by weight. 240.3 g of acetic isopropyl ester having a content of 0.01% by weight of H2O2 are distilled off at a vacuum of between 250 and 350 mbars. The bottom temperature lies betwPen 75 and 77C
and the top temperature reaches a maximal value of 48C. At the bottom there remains 600 g of a 29.91~ by weight anhydrous solution of H2O2 in triethyl phosphate. A residual water content can no longer be detected (smaller than 0.01~ by weight) as measured af~er the production.
Example 2 400.0 g of phthalic diethyl ester are added to 250.0 g of an anhydrous solution of H2O2 in acetic-isopropyl ester contain-ing 44.10~ by weight of hydrogen peroxide and having a residual water content of 0.03% by weight. 138.7 g of acetic-isopropyl 9 _ ester are distilled off via a column at a vacuum of 100 to 50 mbars.
I'he bottom temperature increases from an initial value of 55C to 73.5C. The top temperature reaches a maximal value of 29 C.
508.5 g of a 21.5% by weight anhydrous solution of hydrogen perox-ide in phthalic diethyl ester remains at the bottom. A residual water content can no longer be detected (lower than 0.01% by weight), measured as in Example 1.
Example 3 350 g of N-methyl pyrro]idone-2 are added to 363.0 g of anhydrous solution of H2O2 in acetic-isopropyl ester containing 42.74% by weight of and having a residual water content of 0.03% by weight. 207.3 g of acetic-isopropyl ester are distil-led off via a column at a vacuum of 400 to 350 mbars. The acetic-isopropyl ester has an H2O2 content of 0.05% by weight.
The bottom temperature increases from an initial value of 71 to 76C and the top temperature reaches a maximal value of 53C. 507.0 g of a 30.5% by weight solution of hydrogen peroxide in N-methyl pyrrolidone remains at the bottom. A residual water content is no longer detectable (lower than 0.01% by weight), measured as in Example 1.
Example 4 250.0 g of acetic isopropyl ester and 257.0 g of a 70%
by weight aqueous H2O2 solution (corresponding to 179.9 g of H2O2) are added to 420.0 g of N-methyl pyrrolidone-2. At a vacuum of 350 to 370 mbars and top temperatures of 52 to 56 C, 77.0 g of H2O2 are distilled off via a water separator. The H2O2 content of the distilled ~l2O is 0.05% by weight. The residual acetic-isopropyl ester (249.6 g) is then distilled off at 200 to 250 mbars.
The H2O2 content of the ester is < 0.01% by weight. 608.0 g of a 30 29.6% by weight anhydrous solution of H2O2 in N-methyl pyrrolidone-2 remains at the bottomO The residual water content is 0.01% by weight, measured as in Example 1.
67~
Example 5 395.0 g of a 45.6% by weight anhydrous solution of hyd-rogen peroxide in acetic isopropyl ester (- 180.1 g of H2O2 (100%)) with a residual water content of 0.03~ by weight are added to 420.0 g of tetramethyl urea. At a pressure of 260-170 mbars 213.6 g acetic-isopropyl ester are distilled off via a column. The acetic-isopropyl ester has a hydrogen peroxide content of O.lg by weight.
The bottom temperature increases from an initial value fo 68 C to 74C and the top temperature reaches a maximal value of 46C. 598.2 g of a 29.98~ by weight anhydrous solution of hydrogen peroxide in tetramethyl urea remain at the bottom. A residual water content is no longer detectable (lower than 0.01% by weight) - measured as in Example 1.
o~arison Example for Example 5 449.7 g of a newly distilled tetramethyl urea are added to a solution of 190.8 g of hydrogen peroxide in 84.8 g of water (= a 69.22% by weight aqueous hydrogen peroxide solution). At a vacuum of 65 to 25 mbars 104.03 g of a 15.3~ by weight aqueous H2O2 solution (= 88.0 g of H2O) are distilled off via a column.
The bottom temperature increases from an initial value of 60C to 77.5C and the top temperature reaches a maximum value of 53C.
616.0 g of a 26.23% by weight solution of H~O2 in tetramethyl urea are obtained as the residue.
(The comparison example was not produced by means of the process accordiny to the present invention).
Furthermore, the production of the anhydrous solutions of hydrogen peroxide in phenols or phenol ethers according to DE-AS Nos. 2,462,957 and 2,462,990 requires a high expenditure of energy because of the total evaporation of the phenol component together with the hydrogen peroxide.
At the same time safety problems are encountered due to the common presence of hydorgen peroxide and of the organic compo-nents in the vapour phase, quite apart from the losses of hydrogen peroxide due to the distillation.
As compared therewith, the process according to the pre-sent invention produces the anhydrous solutions which are obtained as a bottom product and not as a top product without any lower boiling entraining agent.
The present invention will be described by way of the following Examples.
Example _ 420O0 g of triethyl phosphate are added to 421 g of a 42.74% by weight solution of hydrogen peroxide in acetic-isopropyl ester (= 179.9 g of H2O2) having a residual water content of 0.03 by weight. 240.3 g of acetic isopropyl ester having a content of 0.01% by weight of H2O2 are distilled off at a vacuum of between 250 and 350 mbars. The bottom temperature lies betwPen 75 and 77C
and the top temperature reaches a maximal value of 48C. At the bottom there remains 600 g of a 29.91~ by weight anhydrous solution of H2O2 in triethyl phosphate. A residual water content can no longer be detected (smaller than 0.01~ by weight) as measured af~er the production.
Example 2 400.0 g of phthalic diethyl ester are added to 250.0 g of an anhydrous solution of H2O2 in acetic-isopropyl ester contain-ing 44.10~ by weight of hydrogen peroxide and having a residual water content of 0.03% by weight. 138.7 g of acetic-isopropyl 9 _ ester are distilled off via a column at a vacuum of 100 to 50 mbars.
I'he bottom temperature increases from an initial value of 55C to 73.5C. The top temperature reaches a maximal value of 29 C.
508.5 g of a 21.5% by weight anhydrous solution of hydrogen perox-ide in phthalic diethyl ester remains at the bottom. A residual water content can no longer be detected (lower than 0.01% by weight), measured as in Example 1.
Example 3 350 g of N-methyl pyrro]idone-2 are added to 363.0 g of anhydrous solution of H2O2 in acetic-isopropyl ester containing 42.74% by weight of and having a residual water content of 0.03% by weight. 207.3 g of acetic-isopropyl ester are distil-led off via a column at a vacuum of 400 to 350 mbars. The acetic-isopropyl ester has an H2O2 content of 0.05% by weight.
The bottom temperature increases from an initial value of 71 to 76C and the top temperature reaches a maximal value of 53C. 507.0 g of a 30.5% by weight solution of hydrogen peroxide in N-methyl pyrrolidone remains at the bottom. A residual water content is no longer detectable (lower than 0.01% by weight), measured as in Example 1.
Example 4 250.0 g of acetic isopropyl ester and 257.0 g of a 70%
by weight aqueous H2O2 solution (corresponding to 179.9 g of H2O2) are added to 420.0 g of N-methyl pyrrolidone-2. At a vacuum of 350 to 370 mbars and top temperatures of 52 to 56 C, 77.0 g of H2O2 are distilled off via a water separator. The H2O2 content of the distilled ~l2O is 0.05% by weight. The residual acetic-isopropyl ester (249.6 g) is then distilled off at 200 to 250 mbars.
The H2O2 content of the ester is < 0.01% by weight. 608.0 g of a 30 29.6% by weight anhydrous solution of H2O2 in N-methyl pyrrolidone-2 remains at the bottomO The residual water content is 0.01% by weight, measured as in Example 1.
67~
Example 5 395.0 g of a 45.6% by weight anhydrous solution of hyd-rogen peroxide in acetic isopropyl ester (- 180.1 g of H2O2 (100%)) with a residual water content of 0.03~ by weight are added to 420.0 g of tetramethyl urea. At a pressure of 260-170 mbars 213.6 g acetic-isopropyl ester are distilled off via a column. The acetic-isopropyl ester has a hydrogen peroxide content of O.lg by weight.
The bottom temperature increases from an initial value fo 68 C to 74C and the top temperature reaches a maximal value of 46C. 598.2 g of a 29.98~ by weight anhydrous solution of hydrogen peroxide in tetramethyl urea remain at the bottom. A residual water content is no longer detectable (lower than 0.01% by weight) - measured as in Example 1.
o~arison Example for Example 5 449.7 g of a newly distilled tetramethyl urea are added to a solution of 190.8 g of hydrogen peroxide in 84.8 g of water (= a 69.22% by weight aqueous hydrogen peroxide solution). At a vacuum of 65 to 25 mbars 104.03 g of a 15.3~ by weight aqueous H2O2 solution (= 88.0 g of H2O) are distilled off via a column.
The bottom temperature increases from an initial value of 60C to 77.5C and the top temperature reaches a maximum value of 53C.
616.0 g of a 26.23% by weight solution of H~O2 in tetramethyl urea are obtained as the residue.
(The comparison example was not produced by means of the process accordiny to the present invention).
Claims (36)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for producing anhydrous solutions of hy-drogen peroxide in higher boiling organic solvents, in which solu-tions of hydrogen peroxide in higher boiling solvents having a water content of up to 1% by weight produced by mixing solutions of hydrogen peroxide in solvents forming one or several azeotropes with water whose boiling points lie below the boiling point of hydrogen peroxide, relative to standard pressure, with higher boiling organic solvents which form no azeotropes with water or only azeotropes which boil close to or above the boiling point of hydrogen peroxide, relative to standard pressure, and the starting solutions of hydrogen peroxide in the solvents forming azeotropes with water whose azeotrope boiling points lie below the boiling of hydrogen peroxide, relative to standard pressure, can also be formed while directly mixing aqueous hydrogen peroxide solutions with these azetrope-forming solvents and the higher boiling solvents, whereupon the entire solvent forming azeotropes with water whose azeotrope boiling point lies below the boiling point of hydrogen peroxide is distilled off and an anhydrous solution of hydrogen peroxide in the corresponding higher boiling solvent is obtained.
2. A process according to claim 1, in which solutions of hydrogen peroxide in organic solvents which form one or several azeotropes whose boiling points lie below the boiling point of hydrogen peroxide and have a water content of up to 1% by weight are used.
3. A process according to claim 2, in which the content of water is below 0.5%.
4. A process according to claim 1, 2 or 3, in which hydrogen peroxide solutions in alkyl or cycloalkyl esters of satura-ted aliphatic carboxylic acids having a total of 4 to 8 carbon atoms are used.
5. A process according to claim 1, 2 or 3, in which hydrogen peroxide solutions in acetic-n-propyl ester or acetic-i-propyl ester are used.
6. A process according to claim 1, in which as the higher boiling solvent there are used phosphorus compounds having the formula wherein X, Y and Z represent an O atom or an N-(Cl-C8)-alkyl group or an N-(C4-C7)-cycloalkyl group, n, m and p represent the number 0 or 1 and Rl, R2 and R3 represent straight-chain or branched Cl-C8-alkyl or C4-C6-cycloalkyl radicals which can be substituted by halogen, hydroxyl, Cl-C4-alkoxy, CN or phenyl groups.
7. A process according to claim 6, in which a trialkyl phosphate with Cl-C8 alkyl groups is used as the higher boiling point solvent.
8. A process according to claim 7, in which the phos-phate is triethyl phosphate.
9. A process according to claim 1, in which esters of aromatic carboxylic acids according to the structural formula are used as higher boiling solvents; in which Rl represents the grouping CH3, C2H5, n-C3H7, i-C3H7, n-C4H9, i-C4H7, tert. C4H9, sec. C4H9, R2 and R3 represent substituents which are inert with respect to hydrogen peroxide and R2 and R3 can be in any position relative to the COO Rl grouping.
10. A process according to claim 7, in which R3 and R4 are selected from H, Cl, F, alkyl, CH3O, C2H5O, and COO R4 where R4 = Rl.
11. A process according to claim 9, in which the alkyl group is selected from those representing Rl.
12. A process according to claim 9, in which phthalic diethyl ester is used as the higher boiling solvent.
13. A process according to claim 1, in which carboxylic amides or lactams having the general formula are used as the higher boiling solvent, in which R represents a straight-chain or branched Cl-C4-alkyl radical which can be sub-stituted by halogen, hydroxyl or Cl-C3-alkyl radicals and n re-presents the number 2 to 5.
14. A process according to claim 13, in which N-alkyl pyrrolidones containing Cl-C4-alkyl groups, are used.
15. A process according to claim 13, in which N-methyl pyrrolidone is used.
16. A process according to claim 1, in which tetra sub-stituted ureas having the formula are used as higher boiling solvents; in which Rl, R2, R3 and R4 represent Cl-C6-alkyl groups.
17. A process according to claim 16, in which Rl, R2, R3 and R4 are identical to each other.
18. A process according to claim 16, in which tetramethyl tetraethyl or tetrabutyl urea are used as the higher boiling sol-vent.
19. A process according to claim 1, 2 or 3, in which the solvent which forms azeotropes with water and whose azeotrope boiling points lie below the boiling point of hydrogen peroxide, relative to standard pressure, is distilled off together with any introduced water as the corresponding azeotrope from the mixture with hydrogen peroxide and the higher boiling solvent under a pressure of 50 to 100 mbars.
20. A process according to claim 1, 2 or 3, in which using aqueous hydrogen peroxide solutions the azeotrope-forming solvent is added in an amount such that the water is completely removed by azeotrope formation.
21. Hydrogen peroxide solutions in phosphorus compounds having the formula wherein X, Y and Z represent an O atom or an N-(Cl-C8)-alkyl group or an N-(C4-C7)-cycloalkyl group, n, m and p represent the number 0 and 1 and Rl, R2 and R3 represent straight-chain or branched Cl-C8-alkyl or C4-C6-cycloalkyl radicals which can be substituted by halogen, hydroxyl groups, Cl-C4-alkoxy, CN or phenyl groups, having a water content of up to 1% by weight.
22. A solution according to claim 21, in which the water content is below 0.5% by weight.
23. Hydrogen peroxide solutions according to claim 21 in trialkyl phosphates containing Cl-C8-alkyl groups, having a water content of up to 1% by weight.
24. A solution according to claim 23, in which the water content is below 0.5% by weight.
25. A solution according to claim 23 or 24 in triethyl phosphate.
26. Hydrogen peroxide solutions in esters or aromatic carboxylic acids having the formula wherein Rl represents the grouping CH3, C2H5, n-C3H7, i-C3H7, n-C4Hg, i-C4H9, tert. C4H9, sec. C4H9, R2 and R3 represent substituents which are inert with respect to hydrogen and R2 and R3 can be in any position relative to the COO Rl grouping, with a water content of up to 1% by weight.
27. A solution according to claim 26, in which the water content is below 0.5% by weight.
28. A solution according to claim 26 or 27, in which R2 and R3 are selected from H, Cl, F, CH3, C2H5 and COO Rl where Rl is as in claim 26.
29. Hydrogen peroxide solutions in carboxylic amides or lactams having the formula wherein R represents a straight-chain or branched Cl-C4 alkyl radical which can be substituted by hydroxyl or Cl-C3-alkyl radi-cals and n represents the number 2 to 5, with a water content of up to 1% by weight.
30. A solution according to claim 29, in which the water content is below 0.5% by weight.
31. Hydrogen peroxide solutions according to claim 29 or 30 in N-alkyl pyrrolidines, containing Cl-C4 alkyl groups.
32. A solution according to claim 29 or 30 in N-methyl-pyrrolidine.
33. Hydrogen peroxide solutions in tetra substituted ureas having the formula wherein Rl, R2, R3 and R4 represent Cl-C6-alkyl groups, ureas, with a water content of up to 1% by weight.
34. A solution according to claim 33, in which the water content is below 0.5% by weight.
35. A solution according to claim 33 or 34, in which Rl, R2, R3 and R4 are identical.
36. Hydrogen peroxide solutions according to claim 33 or 34 in tetramethyl, tetraethyl or tetrabutyl urea.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19833308740 DE3308740A1 (en) | 1983-03-11 | 1983-03-11 | METHOD FOR PRODUCING NON-AQUEOUS HYDROGEN PEROXIDE SOLUTIONS |
| DEP3308740.7 | 1983-03-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1206741A true CA1206741A (en) | 1986-07-02 |
Family
ID=6193221
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000449245A Expired CA1206741A (en) | 1983-03-11 | 1984-03-09 | Process for producing non-aqueous hydrogen peroxide solutions |
Country Status (9)
| Country | Link |
|---|---|
| EP (1) | EP0121660B1 (en) |
| JP (1) | JPS59169906A (en) |
| AT (1) | ATE33615T1 (en) |
| BR (1) | BR8400946A (en) |
| CA (1) | CA1206741A (en) |
| DE (2) | DE3308740A1 (en) |
| ES (1) | ES529731A0 (en) |
| FI (1) | FI72299C (en) |
| IL (1) | IL71040A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| LU85789A1 (en) * | 1985-02-26 | 1986-09-02 | Oreal | USE IN THE THERAPEUTIC AND COSMETIC FIELDS OF AN ANHYDROUS SOLUTION OF HYDROGEN PEROXIDE |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1262982B (en) * | 1966-03-02 | 1968-03-14 | Bayer Ag | Hydrogen peroxide solutions in liquid esters |
| DE2038320C3 (en) * | 1970-08-01 | 1981-05-07 | Bayer Ag, 5090 Leverkusen | Non-aqueous hydrogen peroxide solutions |
| DE2038319C3 (en) * | 1970-08-01 | 1980-09-04 | Bayer Ag, 5090 Leverkusen | Non-aqueous hydrogen peroxide solutions |
| DE3225307A1 (en) * | 1982-07-07 | 1984-01-12 | Degussa Ag, 6000 Frankfurt | METHOD FOR PRODUCING WATER-FREE, ORGANIC HYDROGEN PEROXIDE SOLUTIONS |
-
1983
- 1983-03-11 DE DE19833308740 patent/DE3308740A1/en active Granted
-
1984
- 1984-01-27 AT AT84100839T patent/ATE33615T1/en not_active IP Right Cessation
- 1984-01-27 EP EP84100839A patent/EP0121660B1/en not_active Expired
- 1984-01-27 DE DE8484100839T patent/DE3470515D1/en not_active Expired
- 1984-02-15 ES ES529731A patent/ES529731A0/en active Granted
- 1984-02-20 FI FI840691A patent/FI72299C/en not_active IP Right Cessation
- 1984-02-22 IL IL71040A patent/IL71040A/en unknown
- 1984-02-29 BR BR8400946A patent/BR8400946A/en not_active IP Right Cessation
- 1984-03-09 CA CA000449245A patent/CA1206741A/en not_active Expired
- 1984-03-09 JP JP59044224A patent/JPS59169906A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| ATE33615T1 (en) | 1988-05-15 |
| DE3308740A1 (en) | 1984-09-13 |
| ES8502659A1 (en) | 1985-01-16 |
| JPS59169906A (en) | 1984-09-26 |
| FI72299B (en) | 1987-01-30 |
| IL71040A (en) | 1987-08-31 |
| FI840691A (en) | 1984-09-12 |
| DE3470515D1 (en) | 1988-05-26 |
| FI840691A0 (en) | 1984-02-20 |
| IL71040A0 (en) | 1984-05-31 |
| EP0121660B1 (en) | 1988-04-20 |
| ES529731A0 (en) | 1985-01-16 |
| EP0121660A1 (en) | 1984-10-17 |
| BR8400946A (en) | 1984-10-16 |
| DE3308740C2 (en) | 1987-11-05 |
| FI72299C (en) | 1987-05-11 |
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