WO1997000979A1 - Diaphragm element for an electrolytic filter press assembly - Google Patents

Diaphragm element for an electrolytic filter press assembly Download PDF

Info

Publication number
WO1997000979A1
WO1997000979A1 PCT/NO1996/000152 NO9600152W WO9700979A1 WO 1997000979 A1 WO1997000979 A1 WO 1997000979A1 NO 9600152 W NO9600152 W NO 9600152W WO 9700979 A1 WO9700979 A1 WO 9700979A1
Authority
WO
WIPO (PCT)
Prior art keywords
frame
diaphragm
sealing
elements
bolts
Prior art date
Application number
PCT/NO1996/000152
Other languages
French (fr)
Inventor
Pietro D'erasmo
Roger Mareno Lysfjord
Original Assignee
Norsk Hydro A.S
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
Application filed by Norsk Hydro A.S filed Critical Norsk Hydro A.S
Priority to US08/981,409 priority Critical patent/US5919344A/en
Priority to JP50375597A priority patent/JP3768240B2/en
Priority to EA199800082A priority patent/EA000134B1/en
Priority to CA2225410A priority patent/CA2225410C/en
Priority to EP96922291A priority patent/EP0833963B1/en
Priority to BR9608661A priority patent/BR9608661A/en
Priority to DE69601797T priority patent/DE69601797T2/en
Priority to AU63209/96A priority patent/AU6320996A/en
Publication of WO1997000979A1 publication Critical patent/WO1997000979A1/en

Links

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
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • C25B9/70—Assemblies comprising two or more cells
    • C25B9/73—Assemblies comprising two or more cells of the filter-press type

Definitions

  • the present invention relates to diaphragm elements in an electrolytic filter press assembly comprising anode and cathode compartments separated by diaphragms.
  • Said diaphragm elements comprise a frame, openings for flow of gas and liquids respectively, diaphragm secured to the frame, sealing means and insulating means.
  • the electrolytic filter press assembly is primarily used for production of hydrogen and oxygen from brines, usually aqueous alkali hydroxide solutions. Similar cells are used for production of chlorine from sodium chloride solutions. Such cells can comprise steel frames or frames made of plastic materials. One advantage by using steel frames is that they are rigid and large filter press assemblies can then be made. However, steel frames necessitate insulation and sealing devices between the frames. Corrosion is also a problem to be dealt with. One way of dealing with the corrosion problem is nickel plating of for instance the surfaces of the diaphragm elements that are exposed to the brine or lye to be electrolyzed. But nickel plating is expensive and should be kept to a minimum.
  • Electrolyzers of the above type have been known for a long time and are described in numerous patens.
  • Norwegian patent No. 157024 there is described an electrolyzer of the filter press type for production of hydrogen and oxygen.
  • Each cell consists of bipolar electrodes separated from each other by a diaphragm element.
  • the cells are kept together between two end plates in such a way that the electrolytic cells are kept under constant pressure by longitudinal bolts between said plates.
  • channels for hydrogen and oxygen, respectively are made in the cells.
  • At the lower part of the cells are channels for circulating lye.
  • the main object of the invention was to arrive at a new diaphragm element construction comprising application of steel frames such that large rigid dimensions could be achieved and at the same time attain a construction giving a simpler construction of electrolyzers having fewer elements than the present ones.
  • Another object was to arrive at a common arrangement for sealing, electrical insulation and protection against corrosion.
  • the main problem the inventors had to solve was the corrosion of the steelparts of the diaphragm element and how new and improved sealing and insulating means could be applied without making more complicated and expensive elements.
  • the corrosion problem could be solved by conventional nickel plating of only minor parts of the diaphragm element and then covering the remaining exposed parts with a corrosion resistant material, for instance plastic or rubber material.
  • a corrosion resistant material for instance plastic or rubber material.
  • the diaphragm element also had to be electrically insulated along its circumference, the inventors started investigating the possibility of using the same material for corrosion protection, insulation and sealing. It was then found that not only could the same material be used, but by doing this it became possible to make a more simple and cheap diaphragm element. This was achieved by integrating the corrosion protecting coating of the steel parts of the element with the electrical insulation and the sealing of the diaphragm element.
  • Useful materials for making these integrated corrosion and insulating coatings were found to be vulcanizable rubber having the required electrical insulating and sealing properties.
  • the main new features of the invention comprises that the frame 1 is rigid steel covered by a flexible, vulcanizable material 6 serving as electrical insulation and simultaneously sealing and being integrated with fastening means 4 with openings 7 for bolts for securing the diaphragm 12 to the frame 1.
  • T-formed elements 2,3 form gas/liquid channels with the frame 1 and are secured to same by bolts 5 and covered by material 6 being integral with the sealing/insulating material 6 around the frame 1.
  • the diaphragm 12 is secured to element 2 by a nickel plated element 10 and to element 3 and the frame 1 by means of fastening means 4 being an integral part of the insulating/sealing material 6.
  • fastening means 4 being an integral part of the insulating/sealing material 6.
  • Figure 1 shows a front view of a diaphragm element according to the invention.
  • Figure 2 shows a cross section of the diaphragm element of fig. 1 along line A-A
  • Figure 3 shows a cross section of the frame with insulating and sealing.
  • Figure 1 shows a circular shaped diaphragm element though the shape can also be rectangular or square.
  • the outer frame of the element is a rigid steel frame 1 circumferented by an electrically insulating material 6 which also serves as sealant and is integral with fastening means 4 with openings 7 by which the diaphragm itself is fastened to means 4.
  • T-formed elements 2 and 3 are secured to the frame 1 for forming respective gas channels 8 and lye channels 9.
  • the T-formed elements 2 and 3 are kept in position by bolts 5 when the material 6 is brought onto said elements which thereby are secured gas and liquid impervious. These elements are covered by the material 6 which is vulcanized to said elements.
  • the elements 2 and 3 have respective fastening means 10, 4 by which the diaphragm itself is secured to these elements.
  • Fastening means 10 are nickel plated.
  • FIG 2 the cross section of the diaphragm element is shown along line A-A of figure 1.
  • the cross section goes right through the T-formed element 3, and the lye channel 9 can accordingly not be seen on this figure.
  • the diaphragm 12 is secured by bolts through the openings 7 to the fastening means 4 and 10.
  • the latter is nickel plated, while the former constitutes an integral part of the material circumferenting the steel frame 1.
  • the opening 13 in element 2 is a gas passage from the electrolytic cell to the gas channel 8.
  • Figure 3 is a cross section of the circular frame and shows the steel frame 1 circumferented by the insulating and sealing material 6 and the integral fastening means 4 made of the same material.
  • the opening 7 is for the bolts which shall secure the diaphragm to the fastening means 4.
  • the production costs have been substantially reduced as most of the nickel plating is substituted with vulcanization. As today's nickel plating will require expensive and large chemical baths, the production costs have been substantially reduced as most of the nickel plating is substituted with vulcanization.
  • the electrolyzer will be more compact and the advantages of using the same material for corrosion protection, electrical insulation and sealing will be of great value and simplify the material requirements for the electrolyzer.

Abstract

The present invention relates to diaphragm elements for an electrolytic filter press assembly comprising anode and cathode compartments separated with diaphragms. The diaphragm elements comprise a frame (1) which is rigid steel covered by a flexible vulcanizable material (6) serving as electrical insulation and simultaneously sealing and being integrated with fastening means (4) with openings (7) for bolts for securing the diaphragm (12) to the frame (1). T-formed elements (2, 3) form gas/liquid channels with the frame (1) and are secured to same by bolts (5) and covered by material (6) being integral with the sealing/insulating material (6) around frame (1).

Description

Diaphragm element for an electrolytic filter press assembly
The present invention relates to diaphragm elements in an electrolytic filter press assembly comprising anode and cathode compartments separated by diaphragms. Said diaphragm elements comprise a frame, openings for flow of gas and liquids respectively, diaphragm secured to the frame, sealing means and insulating means.
The electrolytic filter press assembly is primarily used for production of hydrogen and oxygen from brines, usually aqueous alkali hydroxide solutions. Similar cells are used for production of chlorine from sodium chloride solutions. Such cells can comprise steel frames or frames made of plastic materials. One advantage by using steel frames is that they are rigid and large filter press assemblies can then be made. However, steel frames necessitate insulation and sealing devices between the frames. Corrosion is also a problem to be dealt with. One way of dealing with the corrosion problem is nickel plating of for instance the surfaces of the diaphragm elements that are exposed to the brine or lye to be electrolyzed. But nickel plating is expensive and should be kept to a minimum.
Electrolyzers of the above type have been known for a long time and are described in numerous patens. In Norwegian patent No. 157024 there is described an electrolyzer of the filter press type for production of hydrogen and oxygen. Each cell consists of bipolar electrodes separated from each other by a diaphragm element. The cells are kept together between two end plates in such a way that the electrolytic cells are kept under constant pressure by longitudinal bolts between said plates. In the electrolyzer's longitudinal direction, and at its upper part channels for hydrogen and oxygen, respectively are made in the cells. At the lower part of the cells are channels for circulating lye.
From EP 0212240 A1 there is known an apparatus for electrolysis of solutions comprising bipolar elements made up of a conductive plate peripherically surrounded by an insulating frame provided with feeding and discharging channels along peripherical zones of the frame itself. Separating elements can be inserted between said bipolar elements, consisting in a porous diaphragm and an insulating frame also carrying feeding and discharging channels.
The main object of the invention was to arrive at a new diaphragm element construction comprising application of steel frames such that large rigid dimensions could be achieved and at the same time attain a construction giving a simpler construction of electrolyzers having fewer elements than the present ones.
Another object was to arrive at a common arrangement for sealing, electrical insulation and protection against corrosion.
The main problem the inventors had to solve was the corrosion of the steelparts of the diaphragm element and how new and improved sealing and insulating means could be applied without making more complicated and expensive elements. During the development of new solutions to the problem it was found that the corrosion problem could be solved by conventional nickel plating of only minor parts of the diaphragm element and then covering the remaining exposed parts with a corrosion resistant material, for instance plastic or rubber material. Keeping in mind that the diaphragm element also had to be electrically insulated along its circumference, the inventors started investigating the possibility of using the same material for corrosion protection, insulation and sealing. It was then found that not only could the same material be used, but by doing this it became possible to make a more simple and cheap diaphragm element. This was achieved by integrating the corrosion protecting coating of the steel parts of the element with the electrical insulation and the sealing of the diaphragm element.
Useful materials for making these integrated corrosion and insulating coatings were found to be vulcanizable rubber having the required electrical insulating and sealing properties.
By applying the above described principle, only minor parts had to be nickel plated and this could be performed in small nickel plating equipment. It was further found that some of the various elements of the diaphragm element did not have to be joined by welding as previously, but could simply be kept in place by the vulcanized rubber coating. Thus welding could to a great extent be substituted by vulcanization.
The main new features of the invention comprises that the frame 1 is rigid steel covered by a flexible, vulcanizable material 6 serving as electrical insulation and simultaneously sealing and being integrated with fastening means 4 with openings 7 for bolts for securing the diaphragm 12 to the frame 1.
Another special feature of the invention comprises that T-formed elements 2,3 form gas/liquid channels with the frame 1 and are secured to same by bolts 5 and covered by material 6 being integral with the sealing/insulating material 6 around the frame 1.
Preferably the diaphragm 12 is secured to element 2 by a nickel plated element 10 and to element 3 and the frame 1 by means of fastening means 4 being an integral part of the insulating/sealing material 6. The scope of the invention and its special features are as defined by the attached claims.
The invention will now be further explained in connection with the description of the drawings:
Figure 1 shows a front view of a diaphragm element according to the invention.
Figure 2 shows a cross section of the diaphragm element of fig. 1 along line A-A
Figure 3 shows a cross section of the frame with insulating and sealing.
Figure 1 shows a circular shaped diaphragm element though the shape can also be rectangular or square. The outer frame of the element is a rigid steel frame 1 circumferented by an electrically insulating material 6 which also serves as sealant and is integral with fastening means 4 with openings 7 by which the diaphragm itself is fastened to means 4. T-formed elements 2 and 3 are secured to the frame 1 for forming respective gas channels 8 and lye channels 9. The T-formed elements 2 and 3 are kept in position by bolts 5 when the material 6 is brought onto said elements which thereby are secured gas and liquid impervious. These elements are covered by the material 6 which is vulcanized to said elements. The elements 2 and 3 have respective fastening means 10, 4 by which the diaphragm itself is secured to these elements. Fastening means 10 are nickel plated.
In figure 2 the cross section of the diaphragm element is shown along line A-A of figure 1. The cross section goes right through the T-formed element 3, and the lye channel 9 can accordingly not be seen on this figure. The diaphragm 12 is secured by bolts through the openings 7 to the fastening means 4 and 10. The latter is nickel plated, while the former constitutes an integral part of the material circumferenting the steel frame 1. The opening 13 in element 2 is a gas passage from the electrolytic cell to the gas channel 8.
Figure 3 is a cross section of the circular frame and shows the steel frame 1 circumferented by the insulating and sealing material 6 and the integral fastening means 4 made of the same material. The opening 7 is for the bolts which shall secure the diaphragm to the fastening means 4.
By the present invention numerous advantages have been obtained compared with existing solutions. The production costs have been substantially reduced as most of the nickel plating is substituted with vulcanization. As today's nickel plating will require expensive and large chemical baths, the production costs have been substantially reduced as most of the nickel plating is substituted with vulcanization. The electrolyzer will be more compact and the advantages of using the same material for corrosion protection, electrical insulation and sealing will be of great value and simplify the material requirements for the electrolyzer.

Claims

Claims
1. Diaphragm elements for an electrolytic filter press assembly comprising anode and cathode compartments separated by diaphragms (12), said diaphragm elements comprising a frame (1), openings (8,9) for flow of gas and liquid, characterized in that the frame (1) is rigid steel covered by a flexible, vulcanizable material (6) serving as electrical insulation and simultaneously sealing and being integrated with fastening means (4) with openings (7) for bolts for securing the diaphragm (12) to the frame (1).
2. Diaphragm elements according to claim 1 , characterized in that
T-formed elements (2,3) forming gas/liquid channels with the frame (1) are secured to same by bolts (5) and covered by material (6) being integral with the with the sealing/insulating material (6) around the frame (1)
3. Diaphragm elements according to claim 1 , characterized in that the diaphragm (12) is secured to element (2) by a nickel plated element (10) and to element (3) and the frame (1) by means of fastening means (4) being an integral part ofthe insulating/sealing material (6).
PCT/NO1996/000152 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly WO1997000979A1 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US08/981,409 US5919344A (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly
JP50375597A JP3768240B2 (en) 1995-06-23 1996-06-19 Partition element for electrolyte filter press components
EA199800082A EA000134B1 (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly
CA2225410A CA2225410C (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly
EP96922291A EP0833963B1 (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly
BR9608661A BR9608661A (en) 1995-06-23 1996-06-19 Diaphragm components for electrolytic filter press assembly
DE69601797T DE69601797T2 (en) 1995-06-23 1996-06-19 MEMBRANE ELEMENT FOR AN ELECTROLYTIC FILTER PRESS
AU63209/96A AU6320996A (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO19952528A NO303071B1 (en) 1995-06-23 1995-06-23 Diaphragm element for filter press electrolysers
NO952528 1995-06-23

Publications (1)

Publication Number Publication Date
WO1997000979A1 true WO1997000979A1 (en) 1997-01-09

Family

ID=19898340

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1996/000152 WO1997000979A1 (en) 1995-06-23 1996-06-19 Diaphragm element for an electrolytic filter press assembly

Country Status (14)

Country Link
US (1) US5919344A (en)
EP (1) EP0833963B1 (en)
JP (1) JP3768240B2 (en)
CN (1) CN1060540C (en)
AR (1) AR002555A1 (en)
AT (1) ATE177794T1 (en)
AU (1) AU6320996A (en)
BR (1) BR9608661A (en)
CA (1) CA2225410C (en)
DE (1) DE69601797T2 (en)
EA (1) EA000134B1 (en)
NO (1) NO303071B1 (en)
WO (1) WO1997000979A1 (en)
ZA (1) ZA965162B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6554978B1 (en) 1998-10-12 2003-04-29 Vandenborre Technologies Nv High pressure electrolyzer module
US7824527B2 (en) 2003-10-30 2010-11-02 Hugo Jan Baptist Vandenborre Frame for electrolyser module and electrolyser module and electrolyser incorporating same
US8057646B2 (en) 2004-12-07 2011-11-15 Hydrogenics Corporation Electrolyser and components therefor
US9556529B2 (en) 2011-07-20 2017-01-31 New Nel Hydrogen As Electrolyser frame concept, method and use

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3955266B2 (en) * 2003-01-20 2007-08-08 株式会社ムーンスター Gasket manufacturing method and press die structure used therefor
EP1464730A1 (en) * 2003-04-04 2004-10-06 CASALE ChEMICALS S.A. Frame structure for an electrochemical reactor of the filter-press type
PL3460101T3 (en) * 2017-09-21 2020-11-16 Hymeth Aps Electrode for an electrolysis process

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1508758A (en) * 1920-02-03 1924-09-16 John P Scott Electrolytic apparatus
FR631138A (en) * 1926-05-14 1927-12-15 filter press type electrolyser element
CH312582A (en) * 1953-04-17 1956-01-31 Oerlikon Maschf Cell for electrolyzer with pre-electrodes made of perforated sheet metal

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JPS5647267B2 (en) * 1973-03-13 1981-11-09
GB1595183A (en) * 1977-03-04 1981-08-12 Ici Ltd Diaphragm cell
JPS5812836Y2 (en) * 1977-12-26 1983-03-11 鐘淵化学工業株式会社 Membrane installation equipment for alkaline chloride electrolyzer
EP0080287B1 (en) * 1981-11-24 1985-09-25 Imperial Chemical Industries Plc Electrolytic cell of the filter press type
ATE70092T1 (en) * 1984-03-29 1991-12-15 Viscobell S P A FILTER PRESS TYPE ELECTROLYSIS CELL BLOCK FOR WATER ELECTROLYSIS.
US4927509A (en) * 1986-06-04 1990-05-22 H-D Tech Inc. Bipolar electrolyzer
US4915803A (en) * 1988-09-26 1990-04-10 The Dow Chemical Company Combination seal and frame cover member for a filter press type electrolytic cell
US5064514A (en) * 1990-03-30 1991-11-12 Olin Corporation Apparatus for the production of chloric acid
GB9125597D0 (en) * 1991-12-02 1992-01-29 Ici Plc Process for production of a component part of a filter-press type structure
US5421977A (en) * 1993-06-30 1995-06-06 Eltech Systems Corporation Filter press electrolyzer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1508758A (en) * 1920-02-03 1924-09-16 John P Scott Electrolytic apparatus
FR631138A (en) * 1926-05-14 1927-12-15 filter press type electrolyser element
CH312582A (en) * 1953-04-17 1956-01-31 Oerlikon Maschf Cell for electrolyzer with pre-electrodes made of perforated sheet metal

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6554978B1 (en) 1998-10-12 2003-04-29 Vandenborre Technologies Nv High pressure electrolyzer module
US7824527B2 (en) 2003-10-30 2010-11-02 Hugo Jan Baptist Vandenborre Frame for electrolyser module and electrolyser module and electrolyser incorporating same
US8057646B2 (en) 2004-12-07 2011-11-15 Hydrogenics Corporation Electrolyser and components therefor
US9556529B2 (en) 2011-07-20 2017-01-31 New Nel Hydrogen As Electrolyser frame concept, method and use

Also Published As

Publication number Publication date
AR002555A1 (en) 1998-03-25
CN1188517A (en) 1998-07-22
EA199800082A1 (en) 1998-08-27
ZA965162B (en) 1997-02-27
ATE177794T1 (en) 1999-04-15
DE69601797T2 (en) 1999-10-14
CN1060540C (en) 2001-01-10
DE69601797D1 (en) 1999-04-22
CA2225410C (en) 2010-04-27
NO952528D0 (en) 1995-06-23
CA2225410A1 (en) 1997-01-09
EP0833963B1 (en) 1999-03-17
BR9608661A (en) 1999-05-18
EP0833963A1 (en) 1998-04-08
EA000134B1 (en) 1998-10-29
NO952528L (en) 1996-12-27
AU6320996A (en) 1997-01-22
NO303071B1 (en) 1998-05-25
JPH11507992A (en) 1999-07-13
JP3768240B2 (en) 2006-04-19
US5919344A (en) 1999-07-06

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