NO140926B - PROCEDURE FOR OXIDIZATION OF IRON (II) SULPHATE IN AQUATIC SULFURIC ACID SOLUTION TO IRON (III) SULPHATE - Google Patents
PROCEDURE FOR OXIDIZATION OF IRON (II) SULPHATE IN AQUATIC SULFURIC ACID SOLUTION TO IRON (III) SULPHATE Download PDFInfo
- Publication number
- NO140926B NO140926B NO762363A NO762363A NO140926B NO 140926 B NO140926 B NO 140926B NO 762363 A NO762363 A NO 762363A NO 762363 A NO762363 A NO 762363A NO 140926 B NO140926 B NO 140926B
- Authority
- NO
- Norway
- Prior art keywords
- iron
- solution
- sulphate
- sulfuric acid
- oxygen
- Prior art date
Links
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 title claims description 24
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 title claims description 11
- 238000000034 method Methods 0.000 title claims description 10
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 title claims description 4
- 238000007254 oxidation reaction Methods 0.000 title description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 20
- 239000000243 solution Substances 0.000 claims description 16
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 10
- 229910052742 iron Inorganic materials 0.000 claims description 9
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 8
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 239000007789 gas Substances 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 229910000359 iron(II) sulfate Inorganic materials 0.000 claims description 5
- 239000003054 catalyst Substances 0.000 claims description 4
- 230000001590 oxidative effect Effects 0.000 claims description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000013401 experimental design Methods 0.000 claims 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 claims 1
- 239000010413 mother solution Substances 0.000 claims 1
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 5
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical class [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 3
- 229910021577 Iron(II) chloride Inorganic materials 0.000 description 2
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 2
- 238000003776 cleavage reaction Methods 0.000 description 2
- BUACSMWVFUNQET-UHFFFAOYSA-H dialuminum;trisulfate;hydrate Chemical compound O.[Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O BUACSMWVFUNQET-UHFFFAOYSA-H 0.000 description 2
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000012452 mother liquor Substances 0.000 description 2
- 230000007017 scission Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- -1 iron (III) ions Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 description 1
- 229910052939 potassium sulfate Inorganic materials 0.000 description 1
- 239000001120 potassium sulphate Substances 0.000 description 1
- 235000011151 potassium sulphates Nutrition 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/14—Sulfates
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Catalysts (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Treating Waste Gases (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Compounds Of Iron (AREA)
Description
Foreliggende oppfinnelse angår oksydering av jern som foreligger The present invention relates to the oxidation of existing iron
i form av jern(II)sulfat i en vandig løsning med innhold av store mengder fri svovelsyre og eventuelt aluminiumsulfat. in the form of iron (II) sulphate in an aqueous solution containing large amounts of free sulfuric acid and possibly aluminum sulphate.
Jern(II)-salter anses vanligvis å være lett å oksydere i nærvær Iron(II) salts are generally considered to be easily oxidized in the presence
av vann, således at de lett kan omformes til jern(III)-salter. of water, so that they can easily be transformed into iron(III) salts.
På den annen side er disse salter forholdsvis godt løsbare i løs-ninger av ovenfor angitt type som inneholder betraktelige mengder av fri svovelsyre. On the other hand, these salts are relatively well soluble in solutions of the above type which contain considerable amounts of free sulfuric acid.
Den takt hvormed jern(II)sulfat i vandig løsning kan oksyderes er imidlertid vesentlig nedsatt hvis løsningen også inneholder klo-rider eller sulfater (encyclopedia of Chemical Technology, bind 8, side 64, utgave 19 52. Kirk & Othmer, The interscience Encyclopedia Inc. New York). However, the rate at which iron(II) sulfate in aqueous solution can be oxidized is significantly reduced if the solution also contains chlorides or sulfates (encyclopedia of Chemical Technology, volume 8, page 64, issue 19 52. Kirk & Othmer, The interscience Encyclopedia Inc .New York).
I den nye "Traite de Chimie Minerale, bind XVIII, sidene 10 og 81, Masson & Cie., Paris, er det angitt at jern(II)sulfat i kontakt med luft og rent vann frembringer et grunnleggende jern(III)sulfat, nemlig Fe (SO^)^ • Fe2^3 samt svovelsyre, men også at nærvær av et overskudd av svovelsyre hindrer jern(II)sulfat fra å bli hydro-lysert (hydrolyse ville føre til dannelse av et lett oksyderbart sulfat Fe2- (S04)2 OH). In the new "Traite de Chimie Minerale, Volume XVIII, pages 10 and 81, Masson & Cie., Paris, it is stated that iron (II) sulphate in contact with air and pure water produces a basic iron (III) sulphate, viz. Fe (SO^)^ • Fe2^3 as well as sulfuric acid, but also that the presence of an excess of sulfuric acid prevents iron (II) sulphate from being hydrolysed (hydrolysis would lead to the formation of an easily oxidizable sulphate Fe2- (S04) 2 OH).
Hvis en vandig løsning med innhold av 400 g/l H2S04 og 7,2 g/l FeO bringes i intim kontakt med oksygen ved 70°C, vil faktisk 94% av det foreliggende jerninnhold fremdeles befinne seg i jern(Il)-tilstand en time senere, og 91% vil fremdeles være i denne tilstand etter to timer. Nærvær av andre sulfater i løs-ningen vil bare sinke oksyderingen ytterligere. If an aqueous solution containing 400 g/l H2S04 and 7.2 g/l FeO is brought into intimate contact with oxygen at 70°C, in fact 94% of the iron content present will still be in the ferrous state a hour later, and 91% will still be in this state after two hours. The presence of other sulphates in the solution will only slow down the oxidation further.
En industriell prosess for oksydering av jern(II) til jern(III) kan ikke utføres på grunnlag av en sådan langsom reaksjon, og den nettopp nevnte fremgangsmåte for oksydering av en løsning som inneholder jern(II)sulfat, fri svovelsyre og eventuelt andre sulfater ved hjelp av lufttilførsel kan ikke betraktes som en indutriell prosess. An industrial process for oxidizing iron (II) to iron (III) cannot be carried out on the basis of such a slow reaction, and the just-mentioned method for oxidizing a solution containing iron (II) sulfate, free sulfuric acid and possibly other sulfates using air supply cannot be considered an industrial process.
I forbindelse med foreliggende oppfinnelse er det gjort den over-raskende oppdagelse at oksydering av det foreliggende jern(II)-sulfat i en vandig løsning som også inneholder betraktelig eller til og med store mengder av fri svovelsyre, samt eventuelt en stor andel av aluminiumsulfat og muligens også mindre mengder av forskjellige ytterligere sulfater, særlig alkaliske sulfater, vil kunne finne sted meget raskt hvis løsningen også inneholder saltsyre, selv om dette er en reduserende forbindelse. In connection with the present invention, the surprising discovery has been made that oxidation of the present iron (II) sulfate in an aqueous solution which also contains considerable or even large amounts of free sulfuric acid, as well as possibly a large proportion of aluminum sulfate and possibly also smaller amounts of various additional sulfates, especially alkaline sulfates, will be able to take place very quickly if the solution also contains hydrochloric acid, even if this is a reducing compound.
Oppfinnelsen gjelder således en fremgangsmåte for oksydering av jern(II)sulfat oppløst i en vandig løsning som inneholder 250 - 600 g/l svovelsyre, til jern(lll)sulfat ved hjelp av en oksygenholdig gass og en katalysator, idet fremgangsmåtens særtrekk i henhold til oppfinnelsen består i at løsningen tilsettes saltsyre som katalysator i en mengde på 60 - 250 g/l og deretter bringes i intim kontakt med den oksygenholdige gass. The invention thus relates to a method for oxidizing iron (II) sulphate dissolved in an aqueous solution containing 250 - 600 g/l sulfuric acid to iron (II) sulphate with the aid of an oxygen-containing gas and a catalyst, the special features of the method according to the invention consists in the solution adding hydrochloric acid as a catalyst in an amount of 60 - 250 g/l and then bringing it into intimate contact with the oxygen-containing gas.
Ved uttrykket "en oksygenholdig gass" forstås her rent oksygen, ozon eller gassblandinger med vesentlig innhold av oksygen, f.eks. luft. The expression "an oxygen-containing gas" here means pure oxygen, ozone or gas mixtures with a significant content of oxygen, e.g. air.
Temperaturen for den reaksjon som finner sted er ikke kritisk. Det foretrekkes imidlertid å arbeide ved moderate eller lave temperaturer, f.eks. mellom romtemperatur og omkring 50°C, hvor løsbarheten av HCl i svovelsyreløsninger er forhøyet. The temperature of the reaction taking place is not critical. However, it is preferred to work at moderate or low temperatures, e.g. between room temperature and around 50°C, where the solubility of HCl in sulfuric acid solutions is increased.
Reaksjonen kan utføres kontinuerlig eller diskontinuerlig og oksyderingen av jern finner sted meget raskt. I tilfeller hvor den løsning som skal behandles, inneholder aluminiumsulfat som kan være gjenstand for dobbelt spaltning, f.eks. ved reaksjonen: The reaction can be carried out continuously or discontinuously and the oxidation of iron takes place very quickly. In cases where the solution to be treated contains aluminum sulphate which may be subject to double cleavage, e.g. by the reaction:
ledsaget av krystallisasjon av heksahydrert aluminiumklorid, må accompanied by crystallization of hexahydrated aluminum chloride, must
den tilførte mengde saltsyre overskride den mengde som er påkrevet for dobbelt spalting i sådan grad at den frembragte væske vil inne-holde fra 60 - 250 g/l HCl. the added amount of hydrochloric acid exceeds the amount required for double cleavage to such an extent that the liquid produced will contain from 60 - 250 g/l HCl.
En sådan fremgangsmåte kan f.eks. benyttes i en prosess hvor en aluminiumholdig substans med innhold av jern som i det minste del-vis befinner seg i jern(II)-tilstand, reagerer med svovelsyre ute' noen oksydering før denne reaksjon, og danner en svovelholdig løs-ning som hovedsakelig inneholder aluminiumsulfat og jern(II)sulfat. ^. Hvis en sådan løsning behandles for å oppnå utfelling av aluminiumklorid, vil det utfelte materiale bli forurenset av jern(Hj-eller jern(III)-ioner som er nærværende i modervæsken, samt eventuelt også av jern(II)klorid som utfelles samtidig som aluminiumklorid. Selv om størstedelen av det jern som er nærværende i modervæsken kan elimineres ved gjentatte vaskeprosesser, vil dette ikke kunne fjerne den utfelte jern(II)klorid. Forurensning med jern(II)-salter kan unngås hvis vedkommende jern(II)-salt oksyderes til løselig jern(III)-salt, en prosess som lett kan utføres ved hjelp av oppfinnelsens fremgangsmåte. Such a method can e.g. is used in a process where an aluminum-containing substance containing iron, which is at least partially in the iron (II) state, reacts with sulfuric acid without any oxidation before this reaction, and forms a sulfur-containing solution which mainly contains aluminum sulfate and iron(II) sulfate. ^. If such a solution is treated to achieve precipitation of aluminum chloride, the precipitated material will be contaminated by iron (Hj) or iron (III) ions which are present in the mother liquor, and possibly also by iron (II) chloride which is precipitated at the same time as aluminum chloride . Although most of the iron present in the mother liquor can be eliminated by repeated washing processes, this will not be able to remove the precipitated iron(II) chloride. Contamination with iron(II) salts can be avoided if the iron(II) salt in question is oxidized to soluble iron(III) salt, a process which can be easily carried out by means of the method of the invention.
Fremgangsmåten i henhold til foreliggende oppfinnelse gjør det The method according to the present invention does that
mulig å oppnå påfølgende fjerning av jernet i form av dobbelt jern(III)sulfat og kaliumsulfat. possible to achieve subsequent removal of the iron in the form of double iron(III) sulphate and potassium sulphate.
Claims (1)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7521556A FR2317231A1 (en) | 1975-07-09 | 1975-07-09 | PROCESS FOR OXIDIZING FERROUS SULPHATE IN AQUEOUS SULFURIC SOLUTION |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| NO762363L NO762363L (en) | 1977-01-11 |
| NO140926B true NO140926B (en) | 1979-09-03 |
| NO140926C NO140926C (en) | 1979-12-12 |
Family
ID=9157717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO762363A NO140926C (en) | 1975-07-09 | 1976-07-07 | PROCEDURE FOR OXIDIZATION OF IRON (II) SULPHATE IN AQUATIC SULFURIC ACID SOLUTION TO IRON (III) SULPHATE |
Country Status (17)
| Country | Link |
|---|---|
| JP (1) | JPS529697A (en) |
| AU (1) | AU501423B2 (en) |
| BE (1) | BE843925A (en) |
| BR (1) | BR7604434A (en) |
| CA (1) | CA1078137A (en) |
| CH (1) | CH615650A5 (en) |
| DE (1) | DE2630628C3 (en) |
| ES (1) | ES449665A1 (en) |
| FR (1) | FR2317231A1 (en) |
| GB (1) | GB1486759A (en) |
| IL (1) | IL49977A (en) |
| IT (1) | IT1064884B (en) |
| LU (1) | LU75327A1 (en) |
| NL (1) | NL181986C (en) |
| NO (1) | NO140926C (en) |
| SE (1) | SE412576B (en) |
| ZA (1) | ZA764043B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE433843B (en) * | 1982-11-01 | 1984-06-18 | Boliden Ab | PROCEDURE FOR PREPARING A WATER PURIFICATION CHEMICAL |
| JPS648116A (en) * | 1987-06-26 | 1989-01-12 | Toa Gosei Chem Ind | Manufacture of locking screw |
| US5266297A (en) * | 1989-01-20 | 1993-11-30 | Sugita Wire Mfg. Co., Ltd. | Liquid oxidizing method and apparatus |
| JPH02191541A (en) * | 1989-01-20 | 1990-07-27 | Sugita Seisen Kojo:Kk | Oxidation of liquid and equipment thereof |
| JPH0739961U (en) * | 1993-12-28 | 1995-07-18 | タナカプリコート株式会社 | Anti-loosening agent applicator |
| CN112934919B (en) * | 2021-02-05 | 2022-07-01 | 云南大地丰源环保有限公司 | Method for treating waste anhydrous aluminum chloride |
-
1975
- 1975-07-09 FR FR7521556A patent/FR2317231A1/en active Granted
-
1976
- 1976-07-05 SE SE7607679A patent/SE412576B/en not_active IP Right Cessation
- 1976-07-05 CA CA256,249A patent/CA1078137A/en not_active Expired
- 1976-07-06 AU AU15624/76A patent/AU501423B2/en not_active Expired
- 1976-07-06 JP JP51079551A patent/JPS529697A/en active Granted
- 1976-07-06 GB GB28087/76A patent/GB1486759A/en not_active Expired
- 1976-07-06 IL IL49977A patent/IL49977A/en unknown
- 1976-07-07 BR BR4434/76A patent/BR7604434A/en unknown
- 1976-07-07 ZA ZA764043A patent/ZA764043B/en unknown
- 1976-07-07 CH CH869376A patent/CH615650A5/en not_active IP Right Cessation
- 1976-07-07 NO NO762363A patent/NO140926C/en unknown
- 1976-07-07 DE DE2630628A patent/DE2630628C3/en not_active Expired
- 1976-07-07 NL NLAANVRAGE7607523,A patent/NL181986C/en not_active IP Right Cessation
- 1976-07-08 BE BE168752A patent/BE843925A/en not_active IP Right Cessation
- 1976-07-08 ES ES449665A patent/ES449665A1/en not_active Expired
- 1976-07-08 IT IT25131/76A patent/IT1064884B/en active
- 1976-07-08 LU LU75327A patent/LU75327A1/xx unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CH615650A5 (en) | 1980-02-15 |
| JPS5329679B2 (en) | 1978-08-22 |
| LU75327A1 (en) | 1977-04-01 |
| NL181986C (en) | 1987-12-16 |
| AU501423B2 (en) | 1979-06-21 |
| IL49977A (en) | 1979-01-31 |
| NO140926C (en) | 1979-12-12 |
| DE2630628C3 (en) | 1978-10-26 |
| SE7607679L (en) | 1977-01-10 |
| BE843925A (en) | 1976-11-03 |
| AU1562476A (en) | 1978-01-12 |
| IT1064884B (en) | 1985-02-25 |
| CA1078137A (en) | 1980-05-27 |
| NL181986B (en) | 1987-07-16 |
| NL7607523A (en) | 1977-01-11 |
| JPS529697A (en) | 1977-01-25 |
| GB1486759A (en) | 1977-09-21 |
| DE2630628A1 (en) | 1977-01-13 |
| FR2317231B1 (en) | 1977-12-16 |
| ZA764043B (en) | 1977-08-31 |
| DE2630628B2 (en) | 1978-03-02 |
| BR7604434A (en) | 1978-01-31 |
| ES449665A1 (en) | 1977-07-01 |
| IL49977A0 (en) | 1976-09-30 |
| FR2317231A1 (en) | 1977-02-04 |
| SE412576B (en) | 1980-03-10 |
| NO762363L (en) | 1977-01-11 |
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