Classifications

• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
  • A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
  • A62D3/30—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents
  • A62D3/32—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents by treatment in molten chemical reagent, e.g. salts or metals
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
  • A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
  • A62D2101/20—Organic substances
  • A62D2101/22—Organic substances containing halogen

Definitions

• the present invention relates to a process for destroying chlorinated organic products and more particularly aromatic products and polychlorinated biphenyls.
• dielectric liquids contain chlorinated organic products and after a certain period of operation degrade and must be replaced. We can sometimes regenerate them totally or partially. We often have to destroy some of these liquids.
• chlorinated aromatics such as hexachlorobenzene
• PCBs polychlorinated biphenyls
• PCB polychlorinated biphenyls
• European patent EP 170 714 describes the destruction of PCBs by reaction with molten aluminum or an aluminum-based eutectic, the reaction takes place above 382 ° C.
• the Japanese article extracted from NIPPON KAGAKUKAISHI 1977 (9 ) pages 1407 to 1409 describes the partial destruction of PCBs in an AICIs-NaCI-KCI mixture between 400 and 500 ° C.
• the present invention is a process for destroying chlorinated organic products having more than 2 carbon atoms, characterized in that these products are brought into contact with a bath of at least one chloroaluminate, so that the initial concentration of organic products chlorinated in the bath is 4000 ppm or less and preferably 2000 ppm or less.
• chloroaluminates or their mixtures can be used.
• potassium, lithium, sodium, calcium, strontium or ammonium chloroaluminates can be used.
• chloroaluminate is called any mixture of anhydrous aluminum chloride and one or more metal chlorides.
• Sodium chloroaluminate which is preferably used, denotes a mixture of aluminum chloride and sodium chloride in any proportions and not only the equimolecular mixture.
• Sodium chloroaluminate can also contain lithium and / or potassium chloride. We can therefore have any mixture of aluminum chloride, sodium chloride and lithium chloride which is called sodium and lithium chloroaluminate.
• the sodium chloroaluminate contains at least 50 mol% of aluminum chloride and has a melting point of less than 200 ° C.
• the invention is concerned with all chlorinated organic products having more than 2 carbon atoms but it is especially useful for aliphatic, cyclic, mono- or polycyclic, heterocyclic aromatics.
• the invention relates very particularly to perchlorinated aliphatic products and among aromatic products, polychlorinated biphenyls.
• These products can be in any form. They can in particular be in a solid phase, for example absorbed on activated carbon.
• the process according to the invention consists in bringing the chlorinated product into contact with the chloroaluminate bath.
• concentration of chlorinated products is 4000 ppm or less and preferably less than 2000 ppm. This adjustment can for example be obtained by diluting the chlorinated products, advantageously using the same mixture as the chloroaluminate bath.
• the chlorinated product When the chlorinated product is in a solid phase, this solid phase can be poured into the preferably stirred chloroaluminate bath. Care is taken to maintain the molten bath possibly by heating. The same is done if the chlorinated products are in a liquid phase.
• the chlorinated products that one seeks to destroy are in a gas phase alone or in admixture with light chlorinated products and / or carrier gases.
• it may be a gas resulting from combustion, so there is nitrogen containing carbon dioxide, carbon monoxide, chlorine products and possibly oxygen. But it can be any gas mixture taken in any process.
• the chlorinated products are in an anhydrous phase.
• the gas containing the chlorinated products can be dried by contact with an absorbent, for example alumina or glycol.
• this gas phase containing the chlorinated products to be destroyed is brought into contact with the chloroaluminate by any means of bringing a liquid phase into contact with a gas phase. It can be a column with trays or packed. It is also possible in a stirred chloroaluminate tank to introduce the gaseous phase by means of a dip pipe or by a pipe arriving from the bottom of the tank.
• the various chlorinated organic products can be distributed between the liquid and vapor phases of the chloroaluminate bath. The same goes for the products that accompany these chlorinated products. Or can use a tray or packed column to ensure continuous circulation and stirring of the liquid and gas phases and good contact of gaseous products with the chloroalumi bath nate. One can also operate with a cascade of agitated reactors. The chlorinated organic products are kept in contact with the chloroaluminate bath for the time necessary for their destruction. The residence time can vary within wide limits but is generally between a few minutes and a few hours.
• chloroaluminate is liquid
• the chloroaluminate bath can also be purged periodically to avoid the accumulation of insoluble products or products which cannot remain in suspension in the bath. In this purge there is also no trace of chlorinated organic products. We therefore observe the disappearance of the chlorinated products that we sought to destroy.
• one or more powdered metals chosen from reducing metals such as, for example, aluminum or zinc are added to the chloroaluminate bath.
• reducing metals such as, for example, aluminum or zinc
• a powder whose average particle size is less than 500 ! lm. If metals are used, the chlorinated organic products are completely eliminated as before but with a much higher speed, of the order of several times to several tens of times the previous speed.
• metal powder or metals
• chloride is formed by taking chlorine from chlorinated organic products during their destruction.
• metal powder or metals
• aluminum powder up to 5 or 10% by weight of aluminum powder can be placed in the chloroaluminate bath.
• the destruction speed of the chlorinated products increases with the quantity of aluminum powder and with the temperature of the chloroaluminate bath. It is preferred to stir the bath so that the metal powder is well dispersed in the bath.
• the metal chloride (s) which have been produced can mix with the chloroaluminate bath and partition between the liquid and gas phases. If necessary, metal chlorides can be removed from the gas phase by treating it with a hydroxide, such as sodium hydroxide or potassium hydroxide.
• the product is heated to 200 ° C., stirred, then 0.2 g of hexachlorobenzene and 0.1 g of decachlorobiphenyl are introduced. After 1 hour at 200 ° C., the molten bath is swept for 15 minutes at a flow rate of 50 l / h of N 2 , which is washed in a bubbler containing 100 ml of hexane.
• the chlorinated organic compounds are assayed by gas chromatography in the final bath as well as in hexane.

Landscapes

• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
• Dental Preparations (AREA)
• Developing Agents For Electrophotography (AREA)
• Luminescent Compositions (AREA)
• Fire-Extinguishing Compositions (AREA)
• Manufacturing Of Magnetic Record Carriers (AREA)
• Paper (AREA)
• Photoreceptors In Electrophotography (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
• Processing Of Solid Wastes (AREA)
• Food Preservation Except Freezing, Refrigeration, And Drying (AREA)
• Glass Compositions (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9347122

Family Applications (1)

Country Status (17)

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Family Cites Families (3)

• 1987
  • 1987-01-21 FR FR8700669A patent/FR2609652B1/fr not_active Expired - Lifetime
• 1988
  • 1988-01-12 NO NO880104A patent/NO174088C/no unknown
  • 1988-01-13 CA CA000556427A patent/CA1333404C/fr not_active Expired - Fee Related
  • 1988-01-14 DE DE8888400074T patent/DE3860064D1/de not_active Expired - Fee Related
  • 1988-01-14 ES ES88400074T patent/ES2014508B3/es not_active Expired - Lifetime
  • 1988-01-14 AT AT88400074T patent/ATE51531T1/de not_active IP Right Cessation
  • 1988-01-14 EP EP88400074A patent/EP0277858B1/fr not_active Expired - Lifetime
  • 1988-01-19 IN IN34/MAS/88A patent/IN170563B/en unknown
  • 1988-01-19 JP JP63009439A patent/JPS63192468A/ja active Pending
  • 1988-01-19 NZ NZ223232A patent/NZ223232A/en unknown
  • 1988-01-20 CN CN88100299A patent/CN1012142B/zh not_active Expired
  • 1988-01-20 AU AU10621/88A patent/AU610552B2/en not_active Ceased
  • 1988-01-20 IE IE13788A patent/IE60535B1/en not_active IP Right Cessation
  • 1988-01-20 DK DK023288A patent/DK166432B1/da not_active IP Right Cessation
  • 1988-01-20 FI FI880241A patent/FI880241A7/fi not_active Application Discontinuation
  • 1988-01-20 PT PT86577A patent/PT86577B/pt unknown
• 1990
  • 1990-04-18 GR GR90400235T patent/GR3000437T3/el unknown

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