EP0627020A1 - Procede electrochimique de preparation d'acide glyoxylique. - Google Patents

Procede electrochimique de preparation d'acide glyoxylique.

Info

Publication number
EP0627020A1
EP0627020A1 EP93917417A EP93917417A EP0627020A1 EP 0627020 A1 EP0627020 A1 EP 0627020A1 EP 93917417 A EP93917417 A EP 93917417A EP 93917417 A EP93917417 A EP 93917417A EP 0627020 A1 EP0627020 A1 EP 0627020A1
Authority
EP
European Patent Office
Prior art keywords
mol
electrolysis
acid
cathode
metals
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.)
Granted
Application number
EP93917417A
Other languages
German (de)
English (en)
Other versions
EP0627020B1 (fr
Inventor
Bernd Scharbert
Stephen Dapperheld
Pierre Babusiaux
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoechst AG
Original Assignee
Hoechst AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE4205423A external-priority patent/DE4205423C1/de
Priority claimed from DE4217336A external-priority patent/DE4217336C2/de
Application filed by Hoechst AG filed Critical Hoechst AG
Publication of EP0627020A1 publication Critical patent/EP0627020A1/fr
Application granted granted Critical
Publication of EP0627020B1 publication Critical patent/EP0627020B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/20—Processes
    • C25B3/25—Reduction

Definitions

  • the present invention relates to a process for the production of glyoxylic acid by electrochemical reduction of oxalic acid.
  • Glyoxylic acid is an important intermediate for the production of technically relevant compounds and can be produced either by a controlled oxidation of glyoxal or by an electrochemical reduction of oxalic acid.
  • electrochemical reduction of oxalic acid to glyoxylic acid has long been known and is generally carried out in aqueous, acidic medium, at low temperature, on electrodes with high hydrogen overvoltage, for example on electrodes made of lead, cadmium or mercury, with or without the addition of mineral acids and in the presence an ion exchange membrane carried out (DE-AS 163 842, 292 866, 458 438).
  • the object of the present invention is to provide a process for the electrochemical reduction of oxalic acid to glyoxylic acid which avoids the disadvantages mentioned above, in particular has a high selectivity, reaches the lowest possible oxalic acid concentration at the end of the electrolysis and a cathode with a high one Long-term stability used.
  • the cathode should be from a technically well available or material to be processed without problems.
  • Selectivity is understood to mean the ratio of the amount of glyoxylic acid produced to the total amount of products formed during the electrolysis, namely glyoxylic acid plus by-products, for example glycolic acid, acetic acid and formic acid.
  • the object was achieved in that the electrochemical reduction of oxalic acid on cathodes which consist of carbon or at least 50% by weight of at least one of the metals Cu, Ti, Zr, V, Nb, Ta, Fe, Co, Ni, Zn , AI, Sn and Cr are carried out and the electrolyte is or contains salts of metals with a hydrogen overvoltage of at least 0.25 V at a current density of 2500 A / m 2 .
  • the present invention thus relates to a process for the preparation of glyoxylic acid by electrochemical reduction of oxalic acid in aqueous solution in divided or undivided electrolysis cells, characterized in that the cathode is made of carbon or at least 50% by weight of at least one of the metals Cu, Ti , Zr, V, Nb, Ta, Fe, Co, Ni, Zn, Al, Sn and Cr and the aqueous electrolysis solution in the undivided cells or in the cathode compartment of the divided cells also contains at least one salt of metals with a hydrogen overvoltage of at least 0, 25 V, preferably at least 0.40 V, based on a current density of 2500 A / m 2 , contains.
  • All materials which are at least 50% by weight, preferably at least 80% by weight, in particular at least 93% by weight, of one or more of the metals Cu, Ti, Zr, are suitable as cathodes for the process according to the invention.
  • V, Nb, Ta, Fe, Co, Ni, Zn, Al, Sn and Cr, preferably Fe, Co, Ni, Cr, Cu and Ti exist, or all carbon electrode materials, for example electrode graphites, impregnated graphite materials, carbon felts and also glassy carbon.
  • the above-mentioned metallic materials can also be alloys of two or more of the above-mentioned metals, preferably Fe, Co, Ni, Cr, Cu and Ti.
  • Cathodes made of at least 80% by weight, preferably 93 to 96% by weight, of an alloy of two or more metals mentioned above and 0 to 20% by weight, preferably 4 to 7% by weight , from any other metal, preferably Mn, Ti, Mo or a combination thereof, and 0 to 3% by weight, preferably 0 to 1.2% by weight, of a non-metal, preferably C, Si, P , S or a combination of navon.
  • the advantage of using the cathode materials according to the invention is that technically available, inexpensive or easily processable materials can be used. Stainless steel or graphite is particularly preferred.
  • stainless chrome-nickel steels with material numbers 1.4301, 1.4305, 1.4306, 1.4310, 1.4401, 1.4404, 1.4435, 1.4541, 1.4550, 1.4571, 1.4580, 1.4583, 1.4828, 1.4841 and 1.4845 can be used whose compositions are given in percent by weight in the table below.
  • the rest is iron.
  • the method according to the invention is carried out in undivided or preferably in divided cells.
  • the usual diaphragms made of polymers or other organic or inorganic materials, such as glass or ceramics, which are stable in the aqueous electrolysis solution, are used to divide the cells into anode and cathode compartments.
  • Ion exchange membranes in particular cation exchange membranes made of polymers, preferably polymers having carboxyl and / or sulfonic acid groups, are preferably used.
  • the use of stable anion exchange membranes is also possible.
  • the electrolysis can be carried out in all customary electrolysis cells, such as, for example, in beaker or plate and frame cells or cells with fixed bed or fluidized bed electrodes. Both the monopolar and the bipolar circuit of the electrodes can be used.
  • All materials on which the corresponding anode reactions take place can be used as anode material.
  • lead, lead dioxide on lead or other carriers, platinum, metal oxides on titanium, for example titanium dioxide doped with noble metal oxides such as platinum oxide, are suitable for the development of oxygen from dilute sulfuric acid.
  • carbon or titanium dioxide on titanium doped with noble metal oxides are used, for example, for the development of chlorine from aqueous alkali metal chloride solutions.
  • Aqueous mineral acids or solutions of their salts such as, for example, dilute sulfuric or phosphoric acid, dilute or concentrated hydrochloric acid, sodium sulfate or sodium chloride solutions, can be used as the anolyte liquids.
  • the aqueous electrolysis solution in the undivided cell or in the cathode compartment in the divided cell contains the oxalic acid to be electrolyzed in a concentration expediently between about 0.1 mol of oxalic acid per liter of solution and the saturation concentration of oxalic acid in the aqueous electrolysis solution at the electrolysis temperature used.
  • Salts of metals with a hydrogen overvoltage of at least 0.25 V are added to the aqueous electrolysis solution in the undivided cell or in the cathode space of the divided cell.
  • the salts of Cu, Ag, Au, Zn, Cd, -, Hg, Sn, Pb, TI, Ti, Zr, Bi, V, Ta, Cr, Ce, Co or Ni are mainly suitable as salts , preferably the salts of Pb, Sn, Bi, Zn, Cd and Cr, particularly preferably the salts of Pb.
  • the preferred anions of these salts are chloride, sulfate, nitrate or acetate.
  • the salts can be added directly or, for. B. by adding oxides,
  • the salt concentration of the aqueous electrolysis solution in the undivided cell or in the cathode space of the divided cell is expediently set to 10 "7 to 10% by weight, preferably to 10 " 6 to 0.1% by weight, in particular 10 * 5 to 0, 04 wt .-%, each based on the total amount of the aqueous electrolysis solution, adjusted.
  • a salt concentration of 10 "6 to 10% by weight preferably 10 " 5 to 10 "1 % by weight, in particular 10 " 4 to 4 x 10 "2 % by weight, is expedient.
  • metal salts can also be used which form poorly soluble metal oxalates after addition to the aqueous electrolysis solution, for example the oxalates of Cu, Ag, Au, Zn, Cd, Sn, Pb, Ti, Zr, V, Ta, Ce and Co.
  • the added metal ions from the product solution can be removed very easily by filtration after the electrolysis to the saturation concentration.
  • the addition of the salts mentioned can be dispensed with if the above-mentioned metal ions increase in the above-mentioned concentration ranges Start of electrolysis are present in the aqueous electrolyte solution of the undivided cell or in the cathode compartment of the divided cell. It should be noted that the added metal ions must not be present as a metallic alloy component with more than 20% by weight in the cathode material. In this case, the addition of the salts mentioned is necessary in the concentration ranges mentioned above.
  • the presence of the above-mentioned metal ions in the above-mentioned concentration ranges at the beginning of the electrolysis is always to be expected even without the addition of the salts if, after an interruption in operation, for example after a trial in a batch process, a new trial with new catholyte liquid is started without the cathode is changed. In the event of a longer interruption, the cathode can be kept under protective current and the catholyte under inert gas.
  • an electrolysis 10 "7 to 10 wt .-%, preferably 10 " 5 to 0.1 wt .-%, mineral acid such as phosphoric acid, hydrochloric acid, sulfuric acid or nitric acid or organic acids, for example trifluoroacetic acid, formic acid or acetic acid, in the Catholyte fluid can be added.
  • the current density of the method according to the invention is advantageously between 10 and 10,000 A / m 2 , preferably 100 to 5000 A / m 2 , in the case of a carbon cathode between 10 and 5000 A / m 2 , preferably 100 to 4000 A / m 2 .
  • the cell voltage of the method according to the invention is dependent on the current density and is expediently between 1 V and 20 V, preferably between 1 V and 10 V, based on an electrode spacing of 3 mm.
  • the electrolysis temperature can range from - 20 ° C to + 40 ° C. Surprisingly, it was found that at electrolysis temperatures below + 18 ° C, even at oxyacid concentrations less than 1.5 wt .-%, the formation of glycolic acid as a by-product may be less than 1.5 mol% compared to the glyoxylic acid formed. The proportion of glycolic acid increases at higher temperatures.
  • the electrolysis temperature is therefore preferably between + 10 ° C and + 30 ° C, in particular between + 10 ° C and + 18 ° C.
  • the catholyte flow rate of the process according to the invention is between 1 and 10,000, preferably 50 and 2000, in particular 100 and 1000, liters per hour.
  • the product solution is worked up using customary methods.
  • the electrochemical reduction is stopped when a certain turnover has been reached.
  • the resulting glyoxylic acid is separated from any oxalic acid still present in accordance with the prior art mentioned above.
  • the oxalic acid can be selectively fixed to ion exchange resins and the aqueous oxalic acid-free solution can be concentrated in order to obtain a commercial 50% by weight glyoxylic acid.
  • the glyoxylic acid is continuously extracted from the reaction mixture by customary methods and the corresponding equivalent proportion of fresh oxalic acid is added simultaneously.
  • the reaction by-products in particular glycolic acid, acetic acid and formic acid, are not or not completely separated from the glyoxylic acid by these methods. It is therefore important to achieve high selectivity in the process in order to avoid complex cleaning processes.
  • the process according to the invention is characterized in that the proportion of the sum of by-products can be kept very low. It is between 0 and 5 mol%, preferably below 3 mol%, in particular below 2 mol%, relative to the glyoxylic acid.
  • the selectivity of the process according to the invention is all the more remarkable in that, even at a low final concentration of oxalic acid, ie in the range from 0.1 to 0.2 mol of oxalic acid per liter of electrolysis solution, the proportion of by-products is preferably below 3 mol%, based on glyoxylic acid. lies.
  • Another advantage of the method according to the invention is the long-term stability of the cathodes used in comparison to the lead cathodes which have been customary to date.
  • a divided circulation cell which is constructed as follows:
  • Circulation cell with 0.02 m 2 electrode area, electrode spacing 3 mm.
  • A) Cathode stainless steel, material No. 1.4571 (according to DIN 17440), unless otherwise noted.
  • Anode Dimensionally stable anode for oxygen development based on iridium oxide on titanium
  • Cation exchange membrane 2-layer membrane made from copolymers of perfluorosulfonylethoxy vinyl ether + tetrafluoroethylene. On the cathode side there is a layer with the equivalent weight 1300, on the anode side one with the equivalent weight 1100, for example ® Naf ⁇ on 324 from DuPont;
  • Anolyte 2 normal sulfuric acid
  • Example 3 Connection attempt to Example 2
  • Example 5 Connection test to electrolysis according to example 4 electrolysis conditions as example 1
  • Example 6 as example 4, but using a stainless steel cathode with material no. 1.4541 (according to DIN 17 440).
  • Example 7 as example 4, but using a copper cathode with the short name SF-CuF20
  • Anode Dimensionally stable anode for oxygen development based on iridium oxide on titanium
  • Cation exchange membrane 2-layer membrane made from copolymers of perfluorosulfonylethoxy vinyl ether + tetrafluoroethylene. On the cathode side there is a layer with the equivalent weight 1300, on the anode side one with the equivalent weight 1100, for example ® Nafion 324 from DuPont;
  • the quantitative analysis of the components was carried out by means of HPLC, the chemical yield is defined as the amount of glyoxylic acid produced, based on the amount of oxalic acid consumed.
  • the current yield relates to the amount of glyoxylic acid produced.
  • the selectivity has already been defined above.
  • Example 1 The procedure was as in Example 1, except that no lead salt was added, but the electrolysis cell was kept between the electrolysis under protective current and the catholyte under inert gas. The immediately preceding electrolysis was the electrolysis carried out according to Example 1.
  • This example demonstrates the achievement of a high glyoxylic acid concentration at a low oxalic acid concentration while maintaining the high selectivity.
  • the electrolysis time was 10395 Ah without intermediate treatment of the electrochemical cell.
  • the example illustrates that the high selectivity is maintained at an oxalic acid concentration of less than 0.2 mol / l. Chemical yield and current yield are somewhat lower than at higher oxalic acid concentrations.
  • the cathode was rinsed with 10% nitric acid at about 25 ° C for at least 30 minutes. Electrolysis conditions as example 5.
  • the amount of hydrogen developed cathodically was as follows: a) 26 I, b) 5.5 I, c) 12 I, d) 6.1 I, e). 19 I.
  • Example shows that the side reaction of the cathodic hydrogen evolution is suppressed when the metal salts are metered in.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)

Abstract

Un procédé permet de préparer de l'acide glyoxylique par réduction électrochimique d'acide oxalique dans une solution aqueuse dans des cellules d'électrolyse subdivisées ou non. La cathode se compose de carbone ou d'au moins 50 % en poids d'au moins un des métaux Cu, Ti, Zr, V, Nb, Ta, Fe, Co, Ni, Zn, Al, Sn et Cr. La solution aqueuse d'électrolyse dans les cellules non subdivisées ou dans la chambre à cathode des cellules subdivisées contient en outre au moins un sel de métaux ayant une surtension d'hydrogène d'au moins 0,25 V par rapport à une densité de courant de 2500 A/m2. L'avantage de ce procédé est qu'il permet d'utiliser comme matériau cathodique des matériaux techniquement disponibles et économiques, notamment des aciers inoxydables au nickel-chrome ou le graphite.
EP93917417A 1992-02-22 1993-02-02 Procede electrochimique de preparation d'acide glyoxylique Expired - Lifetime EP0627020B1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE4205423 1992-02-22
DE4205423A DE4205423C1 (de) 1992-02-22 1992-02-22 Elektrochemisches Verfahren zur Herstellung von Glyoxylsäure
DE4217336 1992-05-26
DE4217336A DE4217336C2 (de) 1992-05-26 1992-05-26 Elektrochemisches Verfahren zur Herstellung von Glyoxylsäure
PCT/EP1993/000232 WO1993017151A1 (fr) 1992-02-22 1993-02-02 Procede electrochimique de preparation d'acide glyoxylique

Publications (2)

Publication Number Publication Date
EP0627020A1 true EP0627020A1 (fr) 1994-12-07
EP0627020B1 EP0627020B1 (fr) 1996-05-22

Family

ID=25912082

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93917417A Expired - Lifetime EP0627020B1 (fr) 1992-02-22 1993-02-02 Procede electrochimique de preparation d'acide glyoxylique

Country Status (8)

Country Link
US (1) US5474658A (fr)
EP (1) EP0627020B1 (fr)
JP (1) JPH07501854A (fr)
AT (1) ATE138425T1 (fr)
BR (1) BR9305923A (fr)
CA (1) CA2130552A1 (fr)
DE (1) DE59302695D1 (fr)
WO (1) WO1993017151A1 (fr)

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JP2934605B2 (ja) * 1995-08-24 1999-08-16 株式会社日本触媒 α−オキソカルボン酸エステルの製造方法およびそれに用いる触媒
CN101125473B (zh) * 2001-06-06 2012-07-18 新日本制铁株式会社 热浸镀锌薄钢板和热浸镀锌层扩散处理薄钢板及制造方法
US8313634B2 (en) 2009-01-29 2012-11-20 Princeton University Conversion of carbon dioxide to organic products
US20110114502A1 (en) * 2009-12-21 2011-05-19 Emily Barton Cole Reducing carbon dioxide to products
US8500987B2 (en) 2010-03-19 2013-08-06 Liquid Light, Inc. Purification of carbon dioxide from a mixture of gases
US8721866B2 (en) 2010-03-19 2014-05-13 Liquid Light, Inc. Electrochemical production of synthesis gas from carbon dioxide
US8845877B2 (en) 2010-03-19 2014-09-30 Liquid Light, Inc. Heterocycle catalyzed electrochemical process
US8845878B2 (en) 2010-07-29 2014-09-30 Liquid Light, Inc. Reducing carbon dioxide to products
US8568581B2 (en) 2010-11-30 2013-10-29 Liquid Light, Inc. Heterocycle catalyzed carbonylation and hydroformylation with carbon dioxide
US8961774B2 (en) 2010-11-30 2015-02-24 Liquid Light, Inc. Electrochemical production of butanol from carbon dioxide and water
US9090976B2 (en) 2010-12-30 2015-07-28 The Trustees Of Princeton University Advanced aromatic amine heterocyclic catalysts for carbon dioxide reduction
US20130105304A1 (en) 2012-07-26 2013-05-02 Liquid Light, Inc. System and High Surface Area Electrodes for the Electrochemical Reduction of Carbon Dioxide
US9175407B2 (en) 2012-07-26 2015-11-03 Liquid Light, Inc. Integrated process for producing carboxylic acids from carbon dioxide
WO2014100828A1 (fr) * 2012-12-21 2014-06-26 Liquid Light, Inc. Procédé et système de production d'acide oxalique, et produits de la réduction de l'acide oxalique
US8641885B2 (en) 2012-07-26 2014-02-04 Liquid Light, Inc. Multiphase electrochemical reduction of CO2
US8692019B2 (en) 2012-07-26 2014-04-08 Liquid Light, Inc. Electrochemical co-production of chemicals utilizing a halide salt
US10329676B2 (en) 2012-07-26 2019-06-25 Avantium Knowledge Centre B.V. Method and system for electrochemical reduction of carbon dioxide employing a gas diffusion electrode
US9267212B2 (en) 2012-07-26 2016-02-23 Liquid Light, Inc. Method and system for production of oxalic acid and oxalic acid reduction products
US9873951B2 (en) 2012-09-14 2018-01-23 Avantium Knowledge Centre B.V. High pressure electrochemical cell and process for the electrochemical reduction of carbon dioxide
CN110438523B (zh) * 2019-09-05 2021-12-03 南京大学 一种以重水为氘源的无催化剂电化学氘代方法
CN114807988B (zh) * 2022-04-22 2024-06-25 万华化学集团股份有限公司 一种用于电解淀粉合成双醛淀粉的电极材料及其制备方法和一种双醛淀粉的电化学制备方法

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FR2587039B1 (fr) * 1985-09-10 1990-06-08 Hoechst France Procede de fabrication d'oxyde glyoxylique par reduction electrochimique d'acide oxalique
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DE3704915A1 (de) * 1987-02-17 1988-08-25 Hoechst Ag Elektrochemisches verfahren zum austausch von halogenatomen in einer organischen verbindung
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Also Published As

Publication number Publication date
DE59302695D1 (de) 1996-06-27
JPH07501854A (ja) 1995-02-23
US5474658A (en) 1995-12-12
EP0627020B1 (fr) 1996-05-22
ATE138425T1 (de) 1996-06-15
CA2130552A1 (fr) 1993-08-23
WO1993017151A1 (fr) 1993-09-02
BR9305923A (pt) 1997-08-26

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