CA1132996A - Process for producing naphthoquinone - Google Patents
Process for producing naphthoquinoneInfo
- Publication number
- CA1132996A CA1132996A CA363,337A CA363337A CA1132996A CA 1132996 A CA1132996 A CA 1132996A CA 363337 A CA363337 A CA 363337A CA 1132996 A CA1132996 A CA 1132996A
- Authority
- CA
- Canada
- Prior art keywords
- naphthalene
- naphthoquinone
- ceric
- oxidation
- molar
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C46/00—Preparation of quinones
- C07C46/02—Preparation of quinones by oxidation giving rise to quinoid structures
- C07C46/04—Preparation of quinones by oxidation giving rise to quinoid structures of unsubstituted ring carbon atoms in six-membered aromatic rings
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C46/00—Preparation of quinones
- C07C46/10—Separation; Purification; Stabilisation; Use of additives
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A process for producing naphthoquinone. Naphtha-lene is oxidized with ceric sulphate at a temperature above the melting point of naphthalene. There is vigorous agi-tation of the reaction mixture. Sulphuric acid is present but there is no organic solvent. No prior process using cerium oxidants can achieve the same yields.
A process for producing naphthoquinone. Naphtha-lene is oxidized with ceric sulphate at a temperature above the melting point of naphthalene. There is vigorous agi-tation of the reaction mixture. Sulphuric acid is present but there is no organic solvent. No prior process using cerium oxidants can achieve the same yields.
Description
~13Z996 This invention relates to a process for producing naphthoquinone.
Naphthoquinone is a widely used organic material in the chemical process industry. It is used particularly for the production of dyestuffs and higher quinones in~
cluding tetrahydroanthraquinone and anthraquinone.
In Kir~ Othmer's Encyclopedia of Chemical Techno-logy, second edition, volume 16, page 910, it is indicated that l,4-naphthoquinone can be prepared in high yield by the action of potassium dichromate and sulphuric acid on 4-amino-naphthol hydrochloride but that the direct oxidation--of naphthalene to naphthoquinone appears to be of little value. Further, Weyker et al in U.S. Patent 2,938,913 issued May 31st, 1960 describe and claim a method for the direct oxidation of naphthalene to naphthoquinone and phthalic anhydride using a vanadium pentroxide catalyst at high temperatures and in a pressurized system. Although this process of Weyker et al, or modifications of it, are used on a commercial basis, it has the disadvantage of producing a considerable amount of phthalic acid as well as the desired 1,4-naphthoquinone.
Gorbachev and Vabel in Zhur. viz. Khim, 28, 1782 -(8) (1954) describe the oxidation of naphthalene by ceric sulphate at 40 to 70C in a one phase system containing naphthalene, acetic acid, sulphuric acid and ceric sulphate.
They showed that the rate of oxidation of naphthalene appro~imately doubled with each 10C rise in operating temperature. Also, the rate of naphthalene oxidation was approximately first order with a respect to the dissolved ceric ion concentration. Therefore, higher dissolved ceric .~ ~4..~1 ~i~
ion concentrations and higher operating temperatures resulted in more rapid conversion of naphthalene to naphthoquinone.
However, they did not develop a commercially viable naphtho-quinone production method. The naphthoquinone generated in the one phase system they describe is exposed to ceric ion and is thus further oxidized, resulting in low naphtho-quinone yields. Further, their naphthalene and naphtho-quinone concentrations were extremely low. In addition Gorbachev and Vabel did not discuss methods of separating the naphthoquinone from the cerium oxidant.
British Patent 1,192,037 to-Imperial Chemical Industries describes a method for the oxidation of naphtha-lene to naphthoquinone in a two phase system. Naphthalene is dissolved in a variety of solvents at naphthalene con-centrations between 0.05 molar and 0.26 molar to produce ahomogenous organic phase. Ceric sulphate in 4N sulphuric acid or ceric ammonium nitrate in 4N acid is used as a catalyst. Suitable cerium solutions may be prepared having concentrations of 0.01 to 0.15 molar in 4N sulphuric acid.
A more rapid reaction is obtained using the more soluble ceric ammonium nitrate in 4N nitric acid. The use of concentrated ceric ammonium nitrate in nitric acid, although having the advantage of giving a more rapid reaction - as would be expected from the results of Gorbachev and Vabel above - produces a substantial amount of unwanted l-nitro-naphthoquinone byproduct. This failing is also illustrated in ICI's Canadian patent 899,856 and British patent 1,203,434.
The above approach to naphthoquinone production with a cerium oxidant by ICI is not commercially viable as it suffers from a number of drawbacks, including:
~13Z996 1. By using an organic solvent to dissolve the naphthalene, the upper operating temperature is restricted to the boiling point of the solvent.
Naphthoquinone is a widely used organic material in the chemical process industry. It is used particularly for the production of dyestuffs and higher quinones in~
cluding tetrahydroanthraquinone and anthraquinone.
In Kir~ Othmer's Encyclopedia of Chemical Techno-logy, second edition, volume 16, page 910, it is indicated that l,4-naphthoquinone can be prepared in high yield by the action of potassium dichromate and sulphuric acid on 4-amino-naphthol hydrochloride but that the direct oxidation--of naphthalene to naphthoquinone appears to be of little value. Further, Weyker et al in U.S. Patent 2,938,913 issued May 31st, 1960 describe and claim a method for the direct oxidation of naphthalene to naphthoquinone and phthalic anhydride using a vanadium pentroxide catalyst at high temperatures and in a pressurized system. Although this process of Weyker et al, or modifications of it, are used on a commercial basis, it has the disadvantage of producing a considerable amount of phthalic acid as well as the desired 1,4-naphthoquinone.
Gorbachev and Vabel in Zhur. viz. Khim, 28, 1782 -(8) (1954) describe the oxidation of naphthalene by ceric sulphate at 40 to 70C in a one phase system containing naphthalene, acetic acid, sulphuric acid and ceric sulphate.
They showed that the rate of oxidation of naphthalene appro~imately doubled with each 10C rise in operating temperature. Also, the rate of naphthalene oxidation was approximately first order with a respect to the dissolved ceric ion concentration. Therefore, higher dissolved ceric .~ ~4..~1 ~i~
ion concentrations and higher operating temperatures resulted in more rapid conversion of naphthalene to naphthoquinone.
However, they did not develop a commercially viable naphtho-quinone production method. The naphthoquinone generated in the one phase system they describe is exposed to ceric ion and is thus further oxidized, resulting in low naphtho-quinone yields. Further, their naphthalene and naphtho-quinone concentrations were extremely low. In addition Gorbachev and Vabel did not discuss methods of separating the naphthoquinone from the cerium oxidant.
British Patent 1,192,037 to-Imperial Chemical Industries describes a method for the oxidation of naphtha-lene to naphthoquinone in a two phase system. Naphthalene is dissolved in a variety of solvents at naphthalene con-centrations between 0.05 molar and 0.26 molar to produce ahomogenous organic phase. Ceric sulphate in 4N sulphuric acid or ceric ammonium nitrate in 4N acid is used as a catalyst. Suitable cerium solutions may be prepared having concentrations of 0.01 to 0.15 molar in 4N sulphuric acid.
A more rapid reaction is obtained using the more soluble ceric ammonium nitrate in 4N nitric acid. The use of concentrated ceric ammonium nitrate in nitric acid, although having the advantage of giving a more rapid reaction - as would be expected from the results of Gorbachev and Vabel above - produces a substantial amount of unwanted l-nitro-naphthoquinone byproduct. This failing is also illustrated in ICI's Canadian patent 899,856 and British patent 1,203,434.
The above approach to naphthoquinone production with a cerium oxidant by ICI is not commercially viable as it suffers from a number of drawbacks, including:
~13Z996 1. By using an organic solvent to dissolve the naphthalene, the upper operating temperature is restricted to the boiling point of the solvent.
2. By using an organic solvent to dissolve the naphthalene a large and complicated solvent recovery system must be in-cluded in any naphthoquinone production plant. This is prohibitively expensive since a large amount of solvent would have to be removed from a small amount of naphthoquinone product and unconverted naphthalene.
3. By using an organic solvent the initial naphthalene concentration in the organic phase is limited by the solubility of naphthalene in that solvent at the given operating temperature.
4. By using an electrochemical cell contain-ing diaphragms, the maximum ceric ion content of the electrolyte is limited to the maximum solubility of the cerous sulphate salt.
5. Naphthoquinone is produced in extremely dilute concentration, for example 0.2 molar maximum even if 100% yield at 100% conversion were achieved starting with 0.2 molar naphthalene. The cost of recovering extremely dilute naphtho-uinone from a naphthalene solvent mix-ture is prohibitive on a commercial scale.
6. The operating temperature is restricted in the above patents to the range ~0 to 80C in order to restrict the formation of byproducts, for example l-nitronaph-thalene.
7. The reaction rates are slow, for example 1 to 2 hours, because reagents are very dilute and operating temperatures are relatively low. --
8. By having a very dilute naphthalene reagent mixing costs for ensuring that the aqueous ceric ion oxidant and naphthalene reagent are well dispersed are high.
9. The oxidation of naphthalene by ceric sulphate is mass transfer controlled in addition to being kinetically controlled.
The speed at which naphthalene can be converted to naphthoquinone is strongly dependent on the rate at which naphthalene molecules can make contact with ceric ion.
By using a solvent to dissolve naphthalene the ceric ion - naphthalene contact rate is restricted by the speed with which naphthalene molecules within the solvent can diffuse (mass transfer) to the solvent-ceric ion interface where they can react.
By eliminating the solvent entirely a 9~ ' much greater concentration of naphtha-lene molecules is always in direct contact with the ceric ion oxidant.
The speed of the naphthalene oxidation reaction is therefore substantially limited by the use of a solvent. In addition it is important to expose ceric ion to an excess of naphthalene molecules to prevent byproduct formation due to ceric ion reacting with other organic species e.g. naphthoquinone in the absence of naphthalene molecules. Byproduct for-mation and ceric ion wastage is substan-tially reduced by oxidizing naphthalene in the absence of a solvent even at high naphthoquinone concentrations (see Table 1) ~
The present invention seeks to overcome the -`
disadvantages in the prior art that have prevented the production of naphthoquinone by the oxidation of naphthalene using cerium oxidants. The present invention shows that naphthalene can be readily converted to naphthoquinone in very high yields and in high concentrations, higher than demonstrated by ICI or Gorbachev and Vabel, by operating at very high temperatures, for example greater than 81C, without the need for an organic solvent dur~ng the nap-hthalene oxidation and at ceric sulphate concentrations much larger than those disclosed anywhere in the prior art.
Accordingly, in one aspect the present invention is a process for producing naphthoquinone that compri~es oxidizing naphthalene with ceric sulphate at a temperature above the melting point of naphthalene with vigorous agi-tation of the reaction mixture in the presence of sulphuric acid but in the absence of any organic solvent. The mixture resulting from the oxidation may be contacted with an or-ganic solvent to extract the naphthoquinone. Alternatively, fractional sublimation may be used to separate the naph-thoquinone from the reaction mixture.
The sulphuric acid used is preferably in the range 0.5 molar to 2.0 molar.
It should also be noted that the ceric sulphate can be regenerated from the cerous sulphate produced by the oxidation of naphthalene with ceric sulphate, by reoxidizing the cerous sulphate back to the ceric sulphate state.
Techniques for this recovery are known in the art. A
particularly preferred process is described in our co-pending Canadian application Serial Number 351,645 filed May 9th, 1980. However, additional electrolytic processes may be used to regenerate the ceric ion. Ozonolysis may also be used.
The melting point of naphthalene is 80C. A
preferred temperature for carrying out the process is thus at or above about 81C, for example 81 to 85C but higher temperatures can be used. The concentration of the naphtha-lene in the reaction mixture is about 6.3 molar because theconcentration of liquid naphthalene at about 81C is 6.3 molar. The ceric sulphate concentration should be at least 0.05 molar at the start of the naphthalene oxidation, however starting ceric sulphate concentrations in excess of 0.4 molar, particularly 0.5 molar, are preferred.
_, . .
-: .
~1329~36 The following experiments illustrate the inven-tion. The results and reaction conditions are set out in Table 1.
Examples In the following examples the oxidation of naphth-alene was carried out by adding solid naphthalene to a ceric sulphate - sulphuric acid oxidant at or above 81~C. The reaction was carried out in a closed glass container and the contents were stirred vigorously with a magnetic stirrer bar for 15 minutes. The organic mixture resulting was dissolved in an organic solvent and analyzed using high pressure liquid chromatography to determine naphthalene conversion and naphthoquinone yield.
o~
~8 ~3,5 1 o o o o o ~ ~ U~
;~ o o o ,~ ~ ~ ~
~ ~ ~ In ~ I~
-B-"` - 113Z996 The oxidations were carried out in 20 minutes or less, in contrast with the one to two hours required by the prior art. This brief reaction time is due to the defined reaction conditions. By eliminating the use of a solvent the need for a solvent recovery system is eliminated and very concentrated naphthoquinone can be generated, for example about 2 molar, even at moderate naphthalene con-versions, for example 40% or less.
The present invention therefore discloses a commercially viable process for the production of naphtho quinone by the oxidation of naphthalene.
The speed at which naphthalene can be converted to naphthoquinone is strongly dependent on the rate at which naphthalene molecules can make contact with ceric ion.
By using a solvent to dissolve naphthalene the ceric ion - naphthalene contact rate is restricted by the speed with which naphthalene molecules within the solvent can diffuse (mass transfer) to the solvent-ceric ion interface where they can react.
By eliminating the solvent entirely a 9~ ' much greater concentration of naphtha-lene molecules is always in direct contact with the ceric ion oxidant.
The speed of the naphthalene oxidation reaction is therefore substantially limited by the use of a solvent. In addition it is important to expose ceric ion to an excess of naphthalene molecules to prevent byproduct formation due to ceric ion reacting with other organic species e.g. naphthoquinone in the absence of naphthalene molecules. Byproduct for-mation and ceric ion wastage is substan-tially reduced by oxidizing naphthalene in the absence of a solvent even at high naphthoquinone concentrations (see Table 1) ~
The present invention seeks to overcome the -`
disadvantages in the prior art that have prevented the production of naphthoquinone by the oxidation of naphthalene using cerium oxidants. The present invention shows that naphthalene can be readily converted to naphthoquinone in very high yields and in high concentrations, higher than demonstrated by ICI or Gorbachev and Vabel, by operating at very high temperatures, for example greater than 81C, without the need for an organic solvent dur~ng the nap-hthalene oxidation and at ceric sulphate concentrations much larger than those disclosed anywhere in the prior art.
Accordingly, in one aspect the present invention is a process for producing naphthoquinone that compri~es oxidizing naphthalene with ceric sulphate at a temperature above the melting point of naphthalene with vigorous agi-tation of the reaction mixture in the presence of sulphuric acid but in the absence of any organic solvent. The mixture resulting from the oxidation may be contacted with an or-ganic solvent to extract the naphthoquinone. Alternatively, fractional sublimation may be used to separate the naph-thoquinone from the reaction mixture.
The sulphuric acid used is preferably in the range 0.5 molar to 2.0 molar.
It should also be noted that the ceric sulphate can be regenerated from the cerous sulphate produced by the oxidation of naphthalene with ceric sulphate, by reoxidizing the cerous sulphate back to the ceric sulphate state.
Techniques for this recovery are known in the art. A
particularly preferred process is described in our co-pending Canadian application Serial Number 351,645 filed May 9th, 1980. However, additional electrolytic processes may be used to regenerate the ceric ion. Ozonolysis may also be used.
The melting point of naphthalene is 80C. A
preferred temperature for carrying out the process is thus at or above about 81C, for example 81 to 85C but higher temperatures can be used. The concentration of the naphtha-lene in the reaction mixture is about 6.3 molar because theconcentration of liquid naphthalene at about 81C is 6.3 molar. The ceric sulphate concentration should be at least 0.05 molar at the start of the naphthalene oxidation, however starting ceric sulphate concentrations in excess of 0.4 molar, particularly 0.5 molar, are preferred.
_, . .
-: .
~1329~36 The following experiments illustrate the inven-tion. The results and reaction conditions are set out in Table 1.
Examples In the following examples the oxidation of naphth-alene was carried out by adding solid naphthalene to a ceric sulphate - sulphuric acid oxidant at or above 81~C. The reaction was carried out in a closed glass container and the contents were stirred vigorously with a magnetic stirrer bar for 15 minutes. The organic mixture resulting was dissolved in an organic solvent and analyzed using high pressure liquid chromatography to determine naphthalene conversion and naphthoquinone yield.
o~
~8 ~3,5 1 o o o o o ~ ~ U~
;~ o o o ,~ ~ ~ ~
~ ~ ~ In ~ I~
-B-"` - 113Z996 The oxidations were carried out in 20 minutes or less, in contrast with the one to two hours required by the prior art. This brief reaction time is due to the defined reaction conditions. By eliminating the use of a solvent the need for a solvent recovery system is eliminated and very concentrated naphthoquinone can be generated, for example about 2 molar, even at moderate naphthalene con-versions, for example 40% or less.
The present invention therefore discloses a commercially viable process for the production of naphtho quinone by the oxidation of naphthalene.
Claims (9)
1. A process for producing naphthoquinone that comprises oxidizing naphthalene with ceric sulphate at a temperature above the melting point of naphthalene with vigorous agitation of the reaction mixture in the presence of sulphuric acid but in the absence of any organic solvent.
2. A process as claimed in claim 1 including contacting the mixture resulting from the oxidation with an organic solvent to extract the naphthoquinone.
3. A process as claimed in claim 1 including subjecting the mixture resulting from the oxidation to fractional sublimation to separate the naphthoquinone.
4. A process as claimed in claim 1 in which the sulphuric acid used is 0.5 to 2 molar.
5. A process as claimed in claim 1 in which the naphthalene, being in its molten state, is about 6.3 molar.
6. A process as claimed in claim 1 in which the ceric sulphate concentration in the starting reaction mixture is about 0.5 molar.
7. A process as claimed in claim 1 including regenerating the ceric sulphate from the cerous sulphate produced during the oxidation of the naphthalene.
8. A process as claimed in claim 7 in which the regeneration is by electrolysis or by ozonolysis.
9. A process as claimed in claim 1 in which the temperature is at or above about 81°C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA363,337A CA1132996A (en) | 1980-10-27 | 1980-10-27 | Process for producing naphthoquinone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA363,337A CA1132996A (en) | 1980-10-27 | 1980-10-27 | Process for producing naphthoquinone |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1132996A true CA1132996A (en) | 1982-10-05 |
Family
ID=4118272
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA363,337A Expired CA1132996A (en) | 1980-10-27 | 1980-10-27 | Process for producing naphthoquinone |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1132996A (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4536337A (en) * | 1983-04-11 | 1985-08-20 | Kawasaki Kasei Chemicals Ltd. | Process for the preparation of quinones |
| US4632782A (en) * | 1983-05-26 | 1986-12-30 | Kawasaki Kasei Chemicals Limited | Oxidizing an organic compound |
| US4639298A (en) * | 1986-05-05 | 1987-01-27 | W. R. Grace & Co. | Oxidation of organic compounds using ceric ions in aqueous methanesulfonic acid |
| US4647349A (en) * | 1986-05-05 | 1987-03-03 | W. R. Grace & Co. | Oxidation of organic compounds using ceric ions in aqueous trifluoromethanesulfonic acid |
| US4670108A (en) * | 1986-10-10 | 1987-06-02 | W. R. Grace & Co. | Oxidation of organic compounds using ceric methanesulfonate in an aqueous organic solution |
| US4692227A (en) * | 1986-12-01 | 1987-09-08 | W. R. Grace & Co. | Oxidation of organic compounds using thallium ions |
| US4701245A (en) * | 1986-05-05 | 1987-10-20 | W. R. Grace & Co. | Oxidation of organic compounds using a catalyzed cerium (IV) composition |
| EP0244812A1 (en) * | 1986-05-05 | 1987-11-11 | W.R. Grace & Co.-Conn. | Oxidation of organic compounds |
| US5246553A (en) * | 1992-03-05 | 1993-09-21 | Hydro-Quebec | Tetravalent titanium electrolyte and trivalent titanium reducing agent obtained thereby |
| US5250162A (en) * | 1992-01-29 | 1993-10-05 | Metallgesellschaft Ag | Method of reducing Ti(IV) to Ti(III) in acid solution |
| US5296107A (en) * | 1992-03-04 | 1994-03-22 | Hydro-Quebec | Indirect cerium medicated electrosynthesis |
| US5679235A (en) * | 1992-03-05 | 1997-10-21 | Hydro-Quebec | Titanium and cerium containing acidic electrolyte |
| US5705049A (en) * | 1992-04-07 | 1998-01-06 | Hydro-Quebec | Indirect cerium mediated electrosynthesis |
-
1980
- 1980-10-27 CA CA363,337A patent/CA1132996A/en not_active Expired
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4536337A (en) * | 1983-04-11 | 1985-08-20 | Kawasaki Kasei Chemicals Ltd. | Process for the preparation of quinones |
| US4632782A (en) * | 1983-05-26 | 1986-12-30 | Kawasaki Kasei Chemicals Limited | Oxidizing an organic compound |
| US4701245A (en) * | 1986-05-05 | 1987-10-20 | W. R. Grace & Co. | Oxidation of organic compounds using a catalyzed cerium (IV) composition |
| US4647349A (en) * | 1986-05-05 | 1987-03-03 | W. R. Grace & Co. | Oxidation of organic compounds using ceric ions in aqueous trifluoromethanesulfonic acid |
| US4639298A (en) * | 1986-05-05 | 1987-01-27 | W. R. Grace & Co. | Oxidation of organic compounds using ceric ions in aqueous methanesulfonic acid |
| EP0244812A1 (en) * | 1986-05-05 | 1987-11-11 | W.R. Grace & Co.-Conn. | Oxidation of organic compounds |
| US4670108A (en) * | 1986-10-10 | 1987-06-02 | W. R. Grace & Co. | Oxidation of organic compounds using ceric methanesulfonate in an aqueous organic solution |
| US4692227A (en) * | 1986-12-01 | 1987-09-08 | W. R. Grace & Co. | Oxidation of organic compounds using thallium ions |
| US5250162A (en) * | 1992-01-29 | 1993-10-05 | Metallgesellschaft Ag | Method of reducing Ti(IV) to Ti(III) in acid solution |
| US5296107A (en) * | 1992-03-04 | 1994-03-22 | Hydro-Quebec | Indirect cerium medicated electrosynthesis |
| US5516407A (en) * | 1992-03-04 | 1996-05-14 | Hydro Quebec | Indirect cerium mediated electrosynthesis |
| US5246553A (en) * | 1992-03-05 | 1993-09-21 | Hydro-Quebec | Tetravalent titanium electrolyte and trivalent titanium reducing agent obtained thereby |
| US5409581A (en) * | 1992-03-05 | 1995-04-25 | Hydro-Quebec | Tetravalent titanium electrolyte and trivalent titanium reducing agent obtained thereby |
| US5679235A (en) * | 1992-03-05 | 1997-10-21 | Hydro-Quebec | Titanium and cerium containing acidic electrolyte |
| US5705049A (en) * | 1992-04-07 | 1998-01-06 | Hydro-Quebec | Indirect cerium mediated electrosynthesis |
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