WO1988007975A1 - Procede pour diminuer les impuretes dans les lessives dans le procede bayer - Google Patents
Procede pour diminuer les impuretes dans les lessives dans le procede bayer Download PDFInfo
- Publication number
- WO1988007975A1 WO1988007975A1 PCT/CH1988/000076 CH8800076W WO8807975A1 WO 1988007975 A1 WO1988007975 A1 WO 1988007975A1 CH 8800076 W CH8800076 W CH 8800076W WO 8807975 A1 WO8807975 A1 WO 8807975A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- alkali
- membrane
- anion
- electrodialysis
- bayer process
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000004131 Bayer process Methods 0.000 title claims abstract description 21
- 239000012535 impurity Substances 0.000 title abstract description 22
- 239000012528 membrane Substances 0.000 claims abstract description 25
- 238000000909 electrodialysis Methods 0.000 claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 claims abstract description 7
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims abstract description 6
- 239000003513 alkali Substances 0.000 claims description 22
- 150000001450 anions Chemical class 0.000 claims description 8
- 150000001768 cations Chemical class 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 239000000356 contaminant Substances 0.000 claims description 6
- 238000005406 washing Methods 0.000 claims description 4
- 238000004140 cleaning Methods 0.000 claims description 3
- 125000000129 anionic group Chemical group 0.000 claims description 2
- 229960005486 vaccine Drugs 0.000 claims description 2
- 150000002500 ions Chemical class 0.000 claims 2
- 239000000654 additive Substances 0.000 abstract description 2
- 238000004886 process control Methods 0.000 abstract description 2
- 229910021502 aluminium hydroxide Inorganic materials 0.000 abstract 1
- 230000015572 biosynthetic process Effects 0.000 abstract 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 36
- 235000011121 sodium hydroxide Nutrition 0.000 description 16
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 229940039748 oxalate Drugs 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 230000002411 adverse Effects 0.000 description 3
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 3
- 229910001570 bauxite Inorganic materials 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- 239000004021 humic acid Substances 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 2
- 229940043430 calcium compound Drugs 0.000 description 2
- 150000001674 calcium compounds Chemical class 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 238000005868 electrolysis reaction Methods 0.000 description 2
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 239000005708 Sodium hypochlorite Substances 0.000 description 1
- 150000001553 barium compounds Chemical class 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 150000004673 fluoride salts Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005185 salting out Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 1
- ZNCPFRVNHGOPAG-UHFFFAOYSA-L sodium oxalate Chemical compound [Na+].[Na+].[O-]C(=O)C([O-])=O ZNCPFRVNHGOPAG-UHFFFAOYSA-L 0.000 description 1
- 229940039790 sodium oxalate Drugs 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- LSGOVYNHVSXFFJ-UHFFFAOYSA-N vanadate(3-) Chemical class [O-][V]([O-])([O-])=O LSGOVYNHVSXFFJ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/42—Electrodialysis; Electro-osmosis ; Electro-ultrafiltration; Membrane capacitive deionization
- B01D61/44—Ion-selective electrodialysis
- B01D61/445—Ion-selective electrodialysis with bipolar membranes; Water splitting
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
- C01F7/46—Purification of aluminium oxide, aluminium hydroxide or aluminates
- C01F7/47—Purification of aluminium oxide, aluminium hydroxide or aluminates of aluminates, e.g. removal of compounds of Si, Fe, Ga or of organic compounds from Bayer process liquors
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
- C01F7/46—Purification of aluminium oxide, aluminium hydroxide or aluminates
- C01F7/47—Purification of aluminium oxide, aluminium hydroxide or aluminates of aluminates, e.g. removal of compounds of Si, Fe, Ga or of organic compounds from Bayer process liquors
- C01F7/473—Removal of organic compounds, e.g. sodium oxalate
Definitions
- the invention relates to a process for reducing the dissolved inorganic and organic impurities in aqueous alkalis in the Bayer process for the production of aluminum hydroxide.
- the raw materials used in the Bayer process essentially bauxite and caustic soda, contain organic and inorganic undesirable substances which are introduced into the Bayer process in particular during the dissolution of the bauxite and subsequently in a variety of ways affect this adversely.
- the substances are acidic compounds such as Chlorides, phosphates, sulfates, vanadates, fluorides and / or organic salts or acids, in particular oxalates and humic acids.
- the impurities accumulate at various points up to critical values, provided they are not removed from the process.
- Process-related as well as economic problems are associated with the impurities. Cumulatively enriched, since they are obtained in the form of sodium salts, they lead to a reduction in the causticity and the proportion of free lye, which has the consequence that the lye productivity and thus the process economy decrease.
- the process control is hindered by deposits of the undesirable substances on tanks, pipes, heat exchangers and other devices, so that cleaning steps have to be carried out in order to restore the intended production output. Under certain circumstances, the cleaning steps can be quite complex, for example by rinsing acid must be carried out when the deposits reach layer thicknesses that can only be removed inadequately by mechanical means or the deposits are in inadequate places.
- the process economy is further reduced by the impurities in that they increase the alkali viscosity and thus the pump costs increase.
- the settling process of the hydroxide and its separation is negatively influenced.
- the inventors have therefore set themselves the task of presenting a process which is suitable for economically reducing the inorganic and organic dissolved impurities in aqueous alkalis in the Bayer process for the production of aluminum hydroxide and their concentrations in such a manner to keep low limits that they have practically no influence on the Bayer process.
- the object is achieved by a process in which the lye of an electrodialysis using at least one anion-selective and / or at least one cation-permeable membrane and at least one bipolar, water-dissociating membrane to form an alkali lye component, which is the Circulation liquor of the Bayer process is added and subjected to an impurity component which is removed from the process and discarded.
- the contamination level nente essentially contains the anionic acid residues of the contaminants from the contaminated alkali.
- the invention is based on the use of a bipolar membrane in the electrodialysis of the alkali metal hydroxide solution from the Bayer process.
- the generally written reaction takes place
- MX + H2O HX + MOH, where M is alkali and X is the acid residue.
- the salt thus forms as impurity and water, which is dissociated by the bipolar electrode.
- Alkali alkali and the corresponding acid, by the in the corresponding Ze . II areas react by the selective membranes enriched cations or anions with the dissociation products of the water. For example, the following reactions can take place individually or simultaneously:
- FIG. 1 the division of a contaminated lye stream in a cleaned caustic solution and a stream with impurities
- FIGS. 2 to 6 different arrangements of electrodialysis cells
- FIG. 7 the use of the electrodialysis cell (s) in the Bayer process cycle.
- the alkali lye stream P v loaded with impurities and originating from the Bayer process is electrodialysis using at least one anion and / or at least one cation permeable membrane and at least one bipolar membrane to dissociate the water qualified membrane subjected.
- a lye stream P r which is depleted of impurities and a separate current V which contains the impurities are obtained.
- FIGS. 2 to 6 show examples of possible arrangements of electrodialysis units according to the invention. Furthermore, arrows indicate by way of example and schematically in which cell areas the contaminated alkali hydroxide solution P v can be introduced and from which cell areas corresponding reaction products P r , V can be taken or where the / the current (s) of the cleaned ones Alkali P r and the current (s) of the impurities V occur.
- FIG. 7 shows in a highly simplified version the circulation of the lye in the Bayer process and the use of electrodialysis E-
- electrodialysis can also be used in other places of the circulatory process.
- the aforementioned locations are particularly preferred, since the necessary equipment can be installed at these points without significant operational changes and, on the other hand, the lye to be cleaned is diluted, which benefits the life of the membranes.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Inorganic Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Water Supply & Treatment (AREA)
- Urology & Nephrology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Pour diminuer les impuretés solubles minérales et organiques présentes dans les lessives aqueuses dans le procédé Bayer de préparation d'hydroxyde d'aluminium, on utilise des additifs qui nécessitent des procédés coûteux et l'emploi d'une quantité élevée de lessive, ce qui entraîne des coûts de production élevés et ne donne pas dans tous les cas un produit de bonne qualité. Ces inconvénients peuvent être évités en soumettant la lessive impure Pv à une électrodialyse pour laquelle on utilise au moins une membrane à perméabilité sélective anionique et/ou cationique et au moins une membrane bipolaire apte à dissocier l'eau, avec formation d'un composant de lessive alcaline Pr, qui sera rajouté à la lessive dans le processus Bayer, et d'un composant impur VB qui sera éliminé.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| BR888806904A BR8806904A (pt) | 1987-04-15 | 1988-04-11 | Processo para diminuicao de impurezas em lixivias em processo bayer |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH1468/87-0 | 1987-04-15 | ||
| CH146887 | 1987-04-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1988007975A1 true WO1988007975A1 (fr) | 1988-10-20 |
Family
ID=4211189
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/CH1988/000076 WO1988007975A1 (fr) | 1987-04-15 | 1988-04-11 | Procede pour diminuer les impuretes dans les lessives dans le procede bayer |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0309509A1 (fr) |
| CN (1) | CN88102321A (fr) |
| AU (1) | AU610158B2 (fr) |
| BR (1) | BR8806904A (fr) |
| ES (1) | ES2006407A6 (fr) |
| GR (1) | GR880100210A (fr) |
| HU (1) | HUT52005A (fr) |
| WO (1) | WO1988007975A1 (fr) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0310553A1 (fr) * | 1987-10-01 | 1989-04-05 | Alusuisse-Lonza Services Ag | Procédé pour diminuer les impuretés dans des lessives lors du procédé Bayer |
| WO1990006167A1 (fr) * | 1988-12-01 | 1990-06-14 | Allied-Signal Inc. | Procede de purification de bases a partir de materiaux comprenant une base et un sel |
| WO1990012637A3 (fr) * | 1989-03-15 | 1991-01-10 | Pulp Paper Res Inst | Procede d'hydrofractionnement electrodialytique pour le traitement d'electrolytes aqueux |
| US5135626A (en) * | 1988-12-01 | 1992-08-04 | Allied-Signal Inc. | Method for purification of bases from materials comprising base and salt |
| FR2729305A1 (fr) * | 1995-01-18 | 1996-07-19 | Atochem Elf Sa | Regeneration d'acides organiques forts par des membranes bipolaires |
| EP0792896A3 (fr) * | 1996-02-10 | 1998-02-25 | Hüls Aktiengesellschaft | Procédé pour la séparation de lessive de résines de condensation |
| EP0834345A2 (fr) * | 1996-10-03 | 1998-04-08 | Sachem, Inc. | Procédé de purification électrochimique de composés hydroxydes |
| EP0834346A2 (fr) * | 1996-10-03 | 1998-04-08 | Sachem, Inc. | Procédé de purification de composés hydroxydes |
| WO2000034224A1 (fr) * | 1998-12-07 | 2000-06-15 | Basf Aktiengesellschaft | Procedes pour la production ou la purification d'hydroxydes d'onium par electrodialyse |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104016388B (zh) * | 2014-06-12 | 2016-03-30 | 合肥工业大学 | 一种氧化铝生产中碱性料液的分离方法 |
| CN110510714A (zh) * | 2019-08-26 | 2019-11-29 | 北京廷润膜技术开发股份有限公司 | 一种电渗析装置和利用电渗析装置分离碱和盐的方法 |
| CN113044863B (zh) * | 2021-04-25 | 2022-06-21 | 百色学院 | 一种提高氧化铝生产中种分分解率的方法 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4219396A (en) * | 1979-08-03 | 1980-08-26 | Allied Chemical Corporation | Electrodialytic process |
| US4238305A (en) * | 1979-10-29 | 1980-12-09 | Allied Chemical Corporation | Electrodialytic process for the conversion of impure soda values to sodium hydroxide and carbon dioxide |
| US4592817A (en) * | 1984-12-03 | 1986-06-03 | Allied Corporation | Electrodialytic water splitting process for gaseous products |
-
1988
- 1988-03-31 GR GR880100210A patent/GR880100210A/el unknown
- 1988-04-11 EP EP88902782A patent/EP0309509A1/fr not_active Withdrawn
- 1988-04-11 WO PCT/CH1988/000076 patent/WO1988007975A1/fr not_active Application Discontinuation
- 1988-04-11 BR BR888806904A patent/BR8806904A/pt unknown
- 1988-04-11 HU HU882861A patent/HUT52005A/hu unknown
- 1988-04-11 AU AU15433/88A patent/AU610158B2/en not_active Ceased
- 1988-04-13 ES ES8801134A patent/ES2006407A6/es not_active Expired
- 1988-04-15 CN CN198888102321A patent/CN88102321A/zh active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4219396A (en) * | 1979-08-03 | 1980-08-26 | Allied Chemical Corporation | Electrodialytic process |
| US4238305A (en) * | 1979-10-29 | 1980-12-09 | Allied Chemical Corporation | Electrodialytic process for the conversion of impure soda values to sodium hydroxide and carbon dioxide |
| US4592817A (en) * | 1984-12-03 | 1986-06-03 | Allied Corporation | Electrodialytic water splitting process for gaseous products |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0310553A1 (fr) * | 1987-10-01 | 1989-04-05 | Alusuisse-Lonza Services Ag | Procédé pour diminuer les impuretés dans des lessives lors du procédé Bayer |
| WO1990006167A1 (fr) * | 1988-12-01 | 1990-06-14 | Allied-Signal Inc. | Procede de purification de bases a partir de materiaux comprenant une base et un sel |
| US5135626A (en) * | 1988-12-01 | 1992-08-04 | Allied-Signal Inc. | Method for purification of bases from materials comprising base and salt |
| AU632521B2 (en) * | 1988-12-01 | 1993-01-07 | Graver Water Systems, Inc. | Method for purification of bases from materials comprising base and salt |
| WO1990012637A3 (fr) * | 1989-03-15 | 1991-01-10 | Pulp Paper Res Inst | Procede d'hydrofractionnement electrodialytique pour le traitement d'electrolytes aqueux |
| US5993629A (en) * | 1995-01-18 | 1999-11-30 | Elf Atochem S.A. | Regenerating of acids, particularly of strong organic acids, using bipolar membranes |
| WO1996022154A3 (fr) * | 1995-01-18 | 1996-10-10 | Atochem Elf Sa | Regeneration d'acides, notamment d'acides organiques forts, par des membranes bipolaires |
| FR2729305A1 (fr) * | 1995-01-18 | 1996-07-19 | Atochem Elf Sa | Regeneration d'acides organiques forts par des membranes bipolaires |
| EP0792896A3 (fr) * | 1996-02-10 | 1998-02-25 | Hüls Aktiengesellschaft | Procédé pour la séparation de lessive de résines de condensation |
| EP0834345A2 (fr) * | 1996-10-03 | 1998-04-08 | Sachem, Inc. | Procédé de purification électrochimique de composés hydroxydes |
| EP0834346A2 (fr) * | 1996-10-03 | 1998-04-08 | Sachem, Inc. | Procédé de purification de composés hydroxydes |
| EP0834346A3 (fr) * | 1996-10-03 | 1998-11-11 | Sachem, Inc. | Procédé de purification de composés hydroxydes |
| EP0834345A3 (fr) * | 1996-10-03 | 1998-11-11 | Sachem, Inc. | Procédé de purification électrochimique de composés hydroxydes |
| WO2000034224A1 (fr) * | 1998-12-07 | 2000-06-15 | Basf Aktiengesellschaft | Procedes pour la production ou la purification d'hydroxydes d'onium par electrodialyse |
| US6527932B1 (en) | 1998-12-07 | 2003-03-04 | Basf Aktiengesellschaft | Methods for producing or purifying onium hydroxides by means of electrodialysis |
| CN100339355C (zh) * | 1998-12-07 | 2007-09-26 | Basf公司 | 以电渗析制备或纯化的氢氧化物的方法 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN88102321A (zh) | 1988-11-02 |
| ES2006407A6 (es) | 1989-04-16 |
| GR880100210A (el) | 1989-01-31 |
| EP0309509A1 (fr) | 1989-04-05 |
| HUT52005A (en) | 1990-06-28 |
| AU1543388A (en) | 1988-11-04 |
| AU610158B2 (en) | 1991-05-16 |
| BR8806904A (pt) | 1989-10-31 |
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