[go: up one dir, main page]

WO1990007590A1 - Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique - Google Patents

Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique Download PDF

Info

Publication number
WO1990007590A1
WO1990007590A1 PCT/GB1989/000009 GB8900009W WO9007590A1 WO 1990007590 A1 WO1990007590 A1 WO 1990007590A1 GB 8900009 W GB8900009 W GB 8900009W WO 9007590 A1 WO9007590 A1 WO 9007590A1
Authority
WO
WIPO (PCT)
Prior art keywords
powder
liquid
carrier liquid
slurry
recovered
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.)
Ceased
Application number
PCT/GB1989/000009
Other languages
English (en)
Inventor
Stephen Heavens
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.)
Chloride Silent Power Ltd
Original Assignee
Chloride Silent Power Ltd
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 Chloride Silent Power Ltd filed Critical Chloride Silent Power Ltd
Priority to PCT/GB1989/000009 priority Critical patent/WO1990007590A1/fr
Priority to CA002018384A priority patent/CA2018384A1/fr
Publication of WO1990007590A1 publication Critical patent/WO1990007590A1/fr
Priority to BG092787A priority patent/BG92787A/bg
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D13/00—Electrophoretic coating characterised by the process
    • C25D13/22—Servicing or operating apparatus or multistep processes
    • C25D13/24—Regeneration of process liquids
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D13/00—Electrophoretic coating characterised by the process
    • C25D13/02—Electrophoretic coating characterised by the process with inorganic material

Definitions

  • This invention relates to a method o.f recycling organic liquids and method of manufacturing articles by electrophoretic deposition.
  • a suspension of electrically charged particles in a carrier liquid hereinafter referred to as a slurry
  • a carrier liquid hereinafter referred to as a slurry
  • One of the electrodes serves as a mandrel to which the particles are attracted and pressed to form an article.
  • Electrophoretic deposition processes are well known for use for a variety of purposes, one such purpose being the manufacture of the beta alumina electrolyte cup as used in sodium-sulphur electrochemical cells.
  • a liquid medium is used for suspending the particles, that is the beta alumina particles, to be deposited, and it is desirable for such liquid medium to be either cheap so that re-use is not necessary, or reclaimable for re-use to save expenditure.
  • an organic liquid medium can be reclaimed after use in an electrophoretic deposition process simply by allowing or causing the used suspension to separate into solid and liquid phases and then decanting off the supernatant liquid.
  • Drying of the supernatent liquid can then be effected by passage through a molecular sieve.
  • Reference to this method may be found in the article by Robert W. Powers in the Am. Ceram. Soc. Bull., 65[9] 1270-77 (1986) entitled "Ceramic Aspects of
  • Beta Alumina by Electrophoretic Deposition. Drying is required since the presence of water in the reclaimed organic liquid beyond about 0.03% will seriously affect any electrophoretic deposition process carried out using the reclaimed liquid by reversing the charge on the particles suspended therein.
  • One of the particular problems faced when using beta alumina is that the particles require negative charging. The prescence of even very small quantities of water is therefore a problem since the beta alumina is extremely hydroscopic and any hydrogen ions will of course disrupt the charge status.
  • a method of reclaiming an organic liquid used as the suspending medium in an electrophoretic deposition process comprises the steps of separately de-ionising the used liquid and then removing water from the de-ionised liquid. Consequently, the invention is predicated on the appreciation of the deficiencies in previous approaches to recycling organic liquids.
  • de-ionising is effected by distillation, which can be carried out using a conventional single-stage Liebig condenser or solvent recovery plant. It has been found that the distilled liquid then has a conductivity close to that of the original liquid.
  • the step of removing water from the distilled liquid can be carried out by passing the distilled liquid through a molecular sieve.
  • Molecular sieves can be used not only to remove water but also to reduce the conductivity of an organic liquid passed therethrough. However, if used to reduce the conductivity it is necessary for the used organic liquid to be exposed to the sieves for a long time, say two to three weeks, and such extended use of the sieves reduces their efficiency. Further, while such sieves can be regenerated by heating to remove absorbed water, the removal of, for example, absorbed ions is very difficult and the sieves become saturated and inefficient.
  • the molecular sieves are used only to remove absorbed water, and thus can be regenerated by heating and used many times while remaining efficient.
  • the choice of organic liquid is made from a group of organic liquids each having suitable values of properties such as dielectric constant, electrical conductivity, toxicity, flammability, cost and odour.
  • the essential property is that the dielectric constant should fall within the range of 10-20.
  • a yl alcohol is a preferred organic liquid for use for electrophoretic deposition processes since it has particularly acceptable values of these variables.
  • a further problem associated with known techniques of electrophoretic deposition is that when a concentrated slurry is used to manufacture a thin walled article the yield is low because only a small fraction of the powder in the slurry is deposited on the mandrel, the remainder being discarded in the residual slurry remaining after deposition is completed.
  • a method of manufacturing articles by electrophoretic deposition comprising passing a slurry of particles in a carrier liquid between a pair of electrodes, one of which serves as a mandrel on which the particles are deposited to form an article, further comprises separating at least some of the residual slurry, which is slurry which has passed between the electrodes, into recovered powder and recoved carrier liquid and recycling the recovered carrier liquid by the steps of de-ionising and then drying the de-ionised carrier liquid to provide fresh carrier liquid and then adding a powder of particles to the fresh carrier liquid to provide fresh slurry.
  • the added powder may be recovered powder, fresh powder, or a combination of the two.
  • the particles of the powder are preferably given the requisite charge by providing a further step of ionic adsorption.
  • the mixture may preferably be milled to provide the requisite charging. Milling is continued for a time determined to provide an optimum mean particle size.
  • the charging techniques may be interchanged.
  • fresh slurry may also be added to unseparated residual slurry in the ratio of between 1:3 and 3:1, the mixture then being passed between the electrodes for further deposition.
  • the fresh slurry is conveniently made up from recycled carrier liquid.
  • the residual slurry is mixed with fresh slurry in the ratio of 1:1.
  • the method to be described is used for the manufacture of beta alumina bodies as used as solid electrolyte bodies in sodium-sulphur electrochemical cells.
  • raw beta alumina powder 1 is suspended, after treatment 2, in an organic carrier liquid 3, such as amyl alcohol which has been dried using molecular sieves 4, to form a fresh slurry 5.
  • organic carrier liquid 3 such as amyl alcohol which has been dried using molecular sieves 4.
  • Molecular sieves work by allowing internal adsorption of water molecules within the pore structure, the minimum projected cross section of the carrier liquid molecule being greater than the pore size so that the carrier liquid molecule is excluded.
  • amyl alcohol as the carrier liquid
  • a pore size of 0.4 nm has been used. It will be appreciated that the specific choice of sieve pore size will therefore depend on the choice of organic carrier liquid.
  • the slurry is then milled as at 6 to obtain the necessary charging and particle size for the powder, and is then fed to an electrophoretic deposition cell 7 for deposition
  • residual slurry 9 from the cell 7 is returned to the mill 6 for mixing with fresh slurry for supply to the cell 7, the ratio of residual slurry to fresh slurry in the mixture being 1:3 to 3:1.
  • Other residual slurry is separated as at 10 by gravity or centrifugal separation, into recovered powder 11 and recovered carrier liquid 12 components.
  • Recovered carrier liquid is distilled as at 13 and the condensate, free of ionic impurities, is then returned to the molecular sieves 4 for reuse.
  • Recovered powder 11 is dryed as at 14 and de-agglomerated as at 15 before being reused for the preparation of fresh slurry 5.
  • the recovered powder drying stage 14 can be a two-stage operation, these being a first relatively low temperature stage during which carrier liquid is removed, and a second relatively high temperature stage during which water is removed. Further water removal has been found necessary in practice when using powder material of extreme hydroscopicity, such as beta alumina.
  • the recovered powder, after drying can be used in the ratio of 1:3 to 3:1 with fresh powder for fresh slurry preparation. When recovered powder is used as fresh slurry preparation the time of milling at 6 is reduced in order to compensate for the relatively small particle size of the recovered powder .
  • the fresh suspension can be de-gassed as by vacuum or ultrasonic agitation before being fed to the cell 7 in order to further reduce the possibility of the presence of gas bubbles in the article deposited in the cell 7.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Electrostatic Separation (AREA)
  • Separation Of Solids By Using Liquids Or Pneumatic Power (AREA)

Abstract

Les liquides organiques porteurs utilisés en dépôt électrophorétique doivent être recyclés pour des raisons économiques et de sauvegarde de l'environnement. Cette invention concerne le recyclage par les étapes séparées de désionisation et de séchage du liquide porteur afin de produire du liquide porteur neuf.
PCT/GB1989/000009 1989-01-06 1989-01-06 Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique Ceased WO1990007590A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
PCT/GB1989/000009 WO1990007590A1 (fr) 1989-01-06 1989-01-06 Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique
CA002018384A CA2018384A1 (fr) 1989-01-06 1990-06-06 Methode de recyclage de liquides organiques et methode de fabrication d'articles grace a l'electrodeposition par electrophorese
BG092787A BG92787A (bg) 1989-01-06 1990-09-04 Метод за рециклиране на органични течности и метод за производство на изделия чрез електрофорезно отлагане

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/GB1989/000009 WO1990007590A1 (fr) 1989-01-06 1989-01-06 Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique

Publications (1)

Publication Number Publication Date
WO1990007590A1 true WO1990007590A1 (fr) 1990-07-12

Family

ID=10649515

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1989/000009 Ceased WO1990007590A1 (fr) 1989-01-06 1989-01-06 Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique

Country Status (3)

Country Link
BG (1) BG92787A (fr)
CA (1) CA2018384A1 (fr)
WO (1) WO1990007590A1 (fr)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3067120A (en) * 1960-09-02 1962-12-04 Pearlstein Fred Addition agents for improving electrophoretic deposition of aluminum from organic suspensions
GB979948A (en) * 1961-11-15 1965-01-06 British Iron Steel Research Improvements in or relating to the formation of metal coatings by electrophoretic deposition

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3067120A (en) * 1960-09-02 1962-12-04 Pearlstein Fred Addition agents for improving electrophoretic deposition of aluminum from organic suspensions
GB979948A (en) * 1961-11-15 1965-01-06 British Iron Steel Research Improvements in or relating to the formation of metal coatings by electrophoretic deposition

Also Published As

Publication number Publication date
CA2018384A1 (fr) 1991-12-06
BG92787A (bg) 1993-12-24

Similar Documents

Publication Publication Date Title
US9614261B2 (en) Process for recycling electrode materials from lithium-ion batteries
US4048038A (en) Electroflocculation cell
KR101051207B1 (ko) 희토류 금속 산화물을 기반으로 하는 ｌｃｄ 및 ｐｄｐ 유리패널용 재생 무기 연마재 및 이를 제조하기 위한 무기 연마재 폐슬러지 재생 방법
WO2000001519A1 (fr) Procede de separation, de regeneration et de reutilisation d'un glycol a base de coulis use
WO2011078219A1 (fr) Procédé de récupération de poudre comprenant du silicium purifié
WO2024083107A1 (fr) Procédé et dispositif de broyage et de recyclage par voie humide pour batterie au lithium-ion usagée
EP0761603A1 (fr) Procédé et dispositif pour le traitement des eaux usées au cours du polissage de semi-conducteurs
US5298133A (en) Method of recycling organic liquids and a method of manufacturing articles by electrophoretic deposition
CN1234913C (zh) 生产过硫酸钠的方法
US3794250A (en) Process and system for recovering carbon
WO1990007590A1 (fr) Procede de recyclage de liquides organiques et procede de fabrication d'articles par depot electrophoretique
KR101188313B1 (ko) 태양전지용 웨이퍼 제조시 발생되는 폐슬러지 재생방법 및 재생시스템
US4525181A (en) Process for the removal of impurities in reacted alumina
CN106299521A (zh) 一种铅酸蓄电池淋酸废铅泥直接循环回收利用的方法
WO2025097411A1 (fr) Procédé de séparation et de recyclage de batteries usagées
CN115259485B (zh) 一种锂电池电解液生产废水处理及资源回收方法
KR20250143745A (ko) 폐리튬이온전지의 전극으로부터 블랙 매스를 분리하기 위한 방법 및 시스템
CN120129984A (zh) 用于回收碱金属蓄电池的方法及蓄电池处理系统
CN113373461B (zh) 一种同槽电解生产电池级二氧化锰的工艺及设备
US3051636A (en) Electrolytic preparation of cadmium salts
US3804824A (en) Process for purifying organic azo pigments by centrifugation of an agglomerate of the pigment and an organic liquid from an aqueous slurry
US2547231A (en) Electroosmotic isolation of streptomycin
US6863828B2 (en) Process for separation and recovery of polyethylene glycol (PEG) from spent aquesous two-phase systems
Sunderland Electrokinetic dewatering and thickening. III. Electrokinetic cells and their application to a range of materials
KR100626252B1 (ko) 와이어 소 연마제의 재생공정

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): BG