WO1997011032A1 - Process for the preparation of manganese sulphide - Google Patents

Process for the preparation of manganese sulphide Download PDF

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Publication number
WO1997011032A1
WO1997011032A1 PCT/SE1996/001165 SE9601165W WO9711032A1 WO 1997011032 A1 WO1997011032 A1 WO 1997011032A1 SE 9601165 W SE9601165 W SE 9601165W WO 9711032 A1 WO9711032 A1 WO 9711032A1
Authority
WO
WIPO (PCT)
Prior art keywords
reduction
process according
carried out
manganese
carbon monoxide
Prior art date
Application number
PCT/SE1996/001165
Other languages
French (fr)
Inventor
Ulf Engström
Johan Arvidsson
Original Assignee
Höganäs Ab
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 Höganäs Ab filed Critical Höganäs Ab
Priority to DK96932117T priority Critical patent/DK0851841T3/en
Priority to PL96325869A priority patent/PL183820B1/en
Priority to BR9610516A priority patent/BR9610516A/en
Priority to AT96932117T priority patent/ATE199367T1/en
Priority to DE69611924T priority patent/DE69611924T2/en
Priority to JP51264597A priority patent/JP3929071B2/en
Priority to EP96932117A priority patent/EP0851841B1/en
Priority to AU71022/96A priority patent/AU694893B2/en
Priority to CA002232592A priority patent/CA2232592C/en
Publication of WO1997011032A1 publication Critical patent/WO1997011032A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G45/00—Compounds of manganese
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G1/00—Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general
    • C01G1/12—Sulfides

Definitions

  • the present invention concerns a process for the preparation of a manganese sulphide. More specifically, the present invention concerns a reduction process for the preparation of manganese sulphide from manganese sulphate at an elevated temperature.
  • MnS manganese sul ⁇ phide
  • the US patent 4 676 970 discloses a process for the preparation of MnS by melting manganese and sulphur. More specifically this patent discloses a process, according to which an aqueous manganese sulphate solu ⁇ tion is subjected to electrolysis for the preparation of manganese metal, which in particle form is mixed with particulate sulphur. In the obtained mixture, a chemical reaction is initiated by adding eg aluminium and barium peroxide. A very pure MnS product can be obtained if highly pure starting materials are used. Furthermore the patent teaches that it would not be possible to produce MnS on a large scale for commercial purposes by thermal reduction of manganese sulphate due to sulphur pollution and low purity.
  • the JP application 62-288116 discloses a process for the preparation of MnS, whereby an Mn compound such as e.g. MnS0 4 is heated to a temperature between 350 and 700°C in H 2 S atmosphere.
  • Another process for the produc- tion of MnS disclosed in this application concerns the burning of manganese oxide or metallic manganese in car ⁇ bon disulphide atmosphere.
  • the Japanese patent applica ⁇ tion also discloses a method wherein an excess amount of aqueous ammonia is added in the boiling state to an aqueous manganese (II) solution containing potassium oxalate and hydrogen sulphide gas.
  • an MnS product having the required machinability-improving properties can be prepared by thermal reducion of manganese sul ⁇ phate in a process suitable for large-scale commercial production. From an industrial point of view, this process offers important advantages including the possi ⁇ bility to use inexpensive starting materials and avail ⁇ able equipment. Furthermore, the electrolysis step, which is necessary according to the known process, is eliminated. The purity of the obtained product is suffi- cient for industrial purposes and a remarkably pure product can be obtained even without highly pure start ⁇ ing materials as required in the known process.
  • the reduction agent can be selected among a wide variety of known re ⁇ duction agents.
  • the reduction agent is se ⁇ lected from the group consisting of pit coal, charcoal, lignite, gaseous hydrogen, carbon monoxide, since the environmentally accepted products, carbon dioxide or wa ⁇ ter, are then obtained as by-products.
  • the reduction is pre ⁇ ferably carried out in a reducing atmosphere.
  • the process according to the invention is defined in the appended claims.
  • the dry method includes heating manganese sulphate in the presence of a gaseous reduction agent, such as hydrogen gas or carbon monoxide, at a temperature of at least 700°C, preferably at least 750°C and more spe ⁇ cifically at least 800°C.
  • a gaseous reduction agent such as hydrogen gas or carbon monoxide
  • This method is preferably car ⁇ ried out in a fluidized bed, wherein the manganese sul- phate is in the form of agglomerates having a particle size below 10 mm.
  • this process is prefer ⁇ ably carried out in a shaft furnace and sulphur dioxide can be added in order to increase the yield of manganese sulphide.
  • An alternative dry method is mixing particu- late manganese sulphate with particulate carbon in the form of e g pit coal or charcoal at a temperature of at least 700°C, preferably at least 750°C and more spe ⁇ cifically at least 800°C, whereby the particle size of manganese sulphate should preferably be less than 1 mm and the particle size of the carbon should preferably be less than about 5 mm.
  • the wet method can be carried out by mixing par ⁇ ticulate manganese sulphate, particulate coal having a mean particle size of less than about 5 mm, and water, heating the obtained slurry to a temperature of at least 700°C during a period sufficient for allowing essen ⁇ tially complete reduction of manganese sulphate to man ⁇ ganese sulphide.
  • this method is also carried out in a reducing atmosphere such as a carbon monoxide containing atmosphere.
  • the process according to the invention provides an industrially attractive alternative as the starting ma ⁇ terials are inexpensive and readily available.
  • Manganese sulphate is widely used as a fertiliser and the reduc- tion agents are also commonly used and inexpensive, which contributes to the low cost of the process.
  • An additional advantage is that the process can be carried out in conventional equipment, e.g. furnaces, such as belt furnaces and tunnel kilns optionally simultaneously with the other processes conventionally carried out in such equipment.
  • the MnS product obtained according to the present process may include up to 25% by weight of MnO. Quite unexpectedly, it has been found, and this is well docu ⁇ mented, that this relatively high percentage of MnO does not negatively influence the machinability-improving properties.
  • the content of MnO can improve the machinability as compared with a purer MnS product, i.e. a product containing 1% by weight or less of impurities/by- products.
  • a purer MnS product i.e. a product containing 1% by weight or less of impurities/by- products.
  • the product according to the invention can include up to 2 % by weight of C and preferably between 0.5 and 1.5 % by weight of C.
  • Example 1 The invention is further illustrated by the follow ⁇ ing examples: Example 1
  • nS0 IH2O Manganese sulphate obtained from SVERA AB, Sweden, was mixed with 15% particulate charcoal (particle size about 1 mm) and packed in cylindrical SiC-capsules with coke in the center and surrounding the mixture.
  • Each capsule was capable of containing 26 kg of mixture and 9 capsules were simultaneously introduced into the tunnel kiln. The capsules were heated for 36 minutes at a maximum temperature of 1150 - 1180°C. The resulting sponge cakes were crushed, ground and sieved to 45 ⁇ m (325 mesh), leaving a material consisting of MnS having a purity of 98 %. Further refining through grinding and drying is possible.
  • Example 2 Example 2
  • Carbon was added in different forms, such as charcoal, coke or black coal.
  • the resulting MnS/MnO ratio depended strongly upon the type of carbon selected. Experiments carried out at 850°C showed, that charcoal gives the highest MnS content.
  • a slurry was formed by mixing 340 kg of particulate manganese sulphate, 80 kg of particulate carbon in the form of lignite and 80 kg of water.
  • the slurry was pumped into capsules as in example 1 and the capsules were introduced into a tunnel kiln having an atmosphere essentially consisting of carbon monoxide and carbon di ⁇ oxide.
  • the temperature of the kiln was 1150 - 1180°C. All the products prepared according to the above examples had a machinability index of the same magnitude as the MnS product prepared according to the US patent 4 676 970.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Glass Compositions (AREA)
  • Pigments, Carbon Blacks, Or Wood Stains (AREA)

Abstract

The present invention concerns the preparation of a manganese sulphide by heating of particulate or agglomerate manganese sulphate to a temperature of at least 700 °C in the presence of at least one reduction agent.

Description

PROCESS FOR THE PREPARATION OF MANGANESE SULPHIDE
The present invention concerns a process for the preparation of a manganese sulphide. More specifically, the present invention concerns a reduction process for the preparation of manganese sulphide from manganese sulphate at an elevated temperature.
In the field of powder metallurgy manganese sul¬ phide (MnS) has found increasing utility as an additive for improving the machinability of sintered parts. As the market for PM products is expanding, the need for industrially applicable, cost effective and environmen¬ tally acceptable processes is obvious.
The US patent 4 676 970 discloses a process for the preparation of MnS by melting manganese and sulphur. More specifically this patent discloses a process, according to which an aqueous manganese sulphate solu¬ tion is subjected to electrolysis for the preparation of manganese metal, which in particle form is mixed with particulate sulphur. In the obtained mixture, a chemical reaction is initiated by adding eg aluminium and barium peroxide. A very pure MnS product can be obtained if highly pure starting materials are used. Furthermore the patent teaches that it would not be possible to produce MnS on a large scale for commercial purposes by thermal reduction of manganese sulphate due to sulphur pollution and low purity.
The JP application 62-288116 discloses a process for the preparation of MnS, whereby an Mn compound such as e.g. MnS04 is heated to a temperature between 350 and 700°C in H2S atmosphere. Another process for the produc- tion of MnS disclosed in this application concerns the burning of manganese oxide or metallic manganese in car¬ bon disulphide atmosphere. The Japanese patent applica¬ tion also discloses a method wherein an excess amount of aqueous ammonia is added in the boiling state to an aqueous manganese (II) solution containing potassium oxalate and hydrogen sulphide gas.
In accordance with the present invention, it has unexpectedly, and in contrast to the teaching in the above-mentioned patent, been found that an MnS product having the required machinability-improving properties can be prepared by thermal reducion of manganese sul¬ phate in a process suitable for large-scale commercial production. From an industrial point of view, this process offers important advantages including the possi¬ bility to use inexpensive starting materials and avail¬ able equipment. Furthermore, the electrolysis step, which is necessary according to the known process, is eliminated. The purity of the obtained product is suffi- cient for industrial purposes and a remarkably pure product can be obtained even without highly pure start¬ ing materials as required in the known process.
A thorough and extensive study has shown that the thermal reduction can be carried out both as a dry and as a wet process and that satisfactory results can be obtained in many different ways. Thus, the reduction agent can be selected among a wide variety of known re¬ duction agents. Preferably, the reduction agent is se¬ lected from the group consisting of pit coal, charcoal, lignite, gaseous hydrogen, carbon monoxide, since the environmentally accepted products, carbon dioxide or wa¬ ter, are then obtained as by-products. When a solid car¬ bonaceous reduction agent is used the reduction is pre¬ ferably carried out in a reducing atmosphere. By opti- mizing the reaction parameters, a small and environ-men¬ tally acceptable amount of polluting sulphur containing by-products is obtained.
The process according to the invention is defined in the appended claims. The dry method includes heating manganese sulphate in the presence of a gaseous reduction agent, such as hydrogen gas or carbon monoxide, at a temperature of at least 700°C, preferably at least 750°C and more spe¬ cifically at least 800°C. This method is preferably car¬ ried out in a fluidized bed, wherein the manganese sul- phate is in the form of agglomerates having a particle size below 10 mm. Commercially this process is prefer¬ ably carried out in a shaft furnace and sulphur dioxide can be added in order to increase the yield of manganese sulphide. An alternative dry method is mixing particu- late manganese sulphate with particulate carbon in the form of e g pit coal or charcoal at a temperature of at least 700°C, preferably at least 750°C and more spe¬ cifically at least 800°C, whereby the particle size of manganese sulphate should preferably be less than 1 mm and the particle size of the carbon should preferably be less than about 5 mm.
The wet method can be carried out by mixing par¬ ticulate manganese sulphate, particulate coal having a mean particle size of less than about 5 mm, and water, heating the obtained slurry to a temperature of at least 700°C during a period sufficient for allowing essen¬ tially complete reduction of manganese sulphate to man¬ ganese sulphide. Preferably, this method is also carried out in a reducing atmosphere such as a carbon monoxide containing atmosphere.
The process according to the invention provides an industrially attractive alternative as the starting ma¬ terials are inexpensive and readily available. Manganese sulphate is widely used as a fertiliser and the reduc- tion agents are also commonly used and inexpensive, which contributes to the low cost of the process. An additional advantage is that the process can be carried out in conventional equipment, e.g. furnaces, such as belt furnaces and tunnel kilns optionally simultaneously with the other processes conventionally carried out in such equipment. The MnS product obtained according to the present process may include up to 25% by weight of MnO. Quite unexpectedly, it has been found, and this is well docu¬ mented, that this relatively high percentage of MnO does not negatively influence the machinability-improving properties. It has actually been found that in certain cases the content of MnO can improve the machinability as compared with a purer MnS product, i.e. a product containing 1% by weight or less of impurities/by- products. In addition to MnO the product according to the invention can include up to 2 % by weight of C and preferably between 0.5 and 1.5 % by weight of C. By using a stoichiometrical excess of the reduction agent, the amount of MnO can be reduced, and as can be seen from the following examples a highly pure (98 %) MnS product can be obtained even without highly purified starting materials.
The invention is further illustrated by the follow¬ ing examples: Example 1
Manganese sulphate ( nS0 IH2O) obtained from SVERA AB, Sweden, was mixed with 15% particulate charcoal (particle size about 1 mm) and packed in cylindrical SiC-capsules with coke in the center and surrounding the mixture. Each capsule was capable of containing 26 kg of mixture and 9 capsules were simultaneously introduced into the tunnel kiln. The capsules were heated for 36 minutes at a maximum temperature of 1150 - 1180°C. The resulting sponge cakes were crushed, ground and sieved to 45 μm (325 mesh), leaving a material consisting of MnS having a purity of 98 %. Further refining through grinding and drying is possible. Example 2
The following experiments were performed as dry processes at reduction temperatures between 700 and 900°C. a. MnS04 + 2S → MnS + 2S0 b. nS0 + 2C → MnS + 2C02 c. MnS04 + 4H2→ MnS + 4H20
Carbon was added in different forms, such as charcoal, coke or black coal. The resulting MnS/MnO ratio depended strongly upon the type of carbon selected. Experiments carried out at 850°C showed, that charcoal gives the highest MnS content.
Reducing agent MnS/MnO ratio charcoal 90/10 black coal 72/28 coke 32/68 The experiments were carried out without any excess of reducing agent.
All experiments were carried out with 5 minutes of pre¬ heating, a period of 15 minutes of heating to the reduc¬ tion temperature and a period of 60 minutes at the re- duction temperature. Exemple 3
A slurry was formed by mixing 340 kg of particulate manganese sulphate, 80 kg of particulate carbon in the form of lignite and 80 kg of water. The slurry was pumped into capsules as in example 1 and the capsules were introduced into a tunnel kiln having an atmosphere essentially consisting of carbon monoxide and carbon di¬ oxide. The temperature of the kiln was 1150 - 1180°C. All the products prepared according to the above examples had a machinability index of the same magnitude as the MnS product prepared according to the US patent 4 676 970.

Claims

1. Process for the preparation of an manganese sulphide, c h a r a c t e r i s e d by heating particu¬ late or agglomerate manganese sulphate to a temperature of at least 700°C, preferably at least 750°C, in the presence of a at least one reduction agent.
2. Process according to claim 1, c h a r a c t e ¬ r i s e d in that the reduction is carried out in the presence of a reduction agent selected from the group consisting of pit coal, charcoal, lignite, gaseous hydrogen and carbon monoxide.
3. Process according to claim l or 2, c h a r a c ¬ t e r i s e d in that the reduction is carried out as a dry process.
4. Process according to claim 3, c h a r a c t e - r i s e d in that the reduction agent is gaseous hydro¬ gen and/or carbon monoxide and that the manganese sul¬ phate is present in the form of agglomerates.
5. Process according to claim 4, c h a r a c t e ¬ r i s e d in that the reduction is carried out in a shaft furnace.
6. Process according to claim l or 2 c h a r a c - t e r i s e d in that the reduction is carried out as a wet process.
7. Process according to claim 6, c h a r a c - t e r i s e d in that the reduction agent is a solid, particulate, carbonaceous reducing agent, which is mixed with particulate manganese sulphate and water, that the obtained slurry is heated to a temperature of at least 700°C, preferably at least 750°C, for a period sufficient for allowing an essentially complete reduc¬ tion of the manganese sulphate.
8. Process according to claim 7, c h a r a c t e ¬ r i s e d in that the reduction is carried out at a tem¬ perature of at least 1100°C in a reducing atmosphere.
9. Process according to claim 8, c h a r a c t e ¬ r i s e d in that the reduction is carried out at a tem¬ perature of 1100 to 1180°C in an atmosphere essentially consisting of carbon monoxide and carbon dioxide.
10. Process according to any of the claims 6 to 9 c h a r a c t e r i s e d in that the process is car¬ ried out in a tunnel kiln.
PCT/SE1996/001165 1995-09-22 1996-09-20 Process for the preparation of manganese sulphide WO1997011032A1 (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
DK96932117T DK0851841T3 (en) 1995-09-22 1996-09-20 Method of production of manganese sulphide
PL96325869A PL183820B1 (en) 1995-09-22 1996-09-20 Method of obtaining manganese sulphide
BR9610516A BR9610516A (en) 1995-09-22 1996-09-20 Process for the preparation of manganese sulfide
AT96932117T ATE199367T1 (en) 1995-09-22 1996-09-20 METHOD FOR PRODUCING MANGANESE SULFIDE
DE69611924T DE69611924T2 (en) 1995-09-22 1996-09-20 METHOD FOR PRODUCING MANGANESULFIDE
JP51264597A JP3929071B2 (en) 1995-09-22 1996-09-20 Method for producing manganese sulfide
EP96932117A EP0851841B1 (en) 1995-09-22 1996-09-20 Process for the preparation of manganese sulphide
AU71022/96A AU694893B2 (en) 1995-09-22 1996-09-20 Process for the preparation of manganese sulphide
CA002232592A CA2232592C (en) 1995-09-22 1996-09-20 Process for the preparation of manganese sulphide

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9503322A SE9503322D0 (en) 1995-09-22 1995-09-22 Process for the preraton of manganese sulphide
SE9503322-1 1995-09-22

Publications (1)

Publication Number Publication Date
WO1997011032A1 true WO1997011032A1 (en) 1997-03-27

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1996/001165 WO1997011032A1 (en) 1995-09-22 1996-09-20 Process for the preparation of manganese sulphide

Country Status (15)

Country Link
EP (1) EP0851841B1 (en)
JP (1) JP3929071B2 (en)
KR (1) KR100444740B1 (en)
CN (1) CN1084713C (en)
AT (1) ATE199367T1 (en)
AU (1) AU694893B2 (en)
BR (1) BR9610516A (en)
CA (1) CA2232592C (en)
DE (1) DE69611924T2 (en)
DK (1) DK0851841T3 (en)
ES (1) ES2154836T3 (en)
MX (1) MX9802289A (en)
PL (1) PL183820B1 (en)
SE (1) SE9503322D0 (en)
WO (1) WO1997011032A1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101665270B (en) * 2009-09-27 2011-08-31 武汉理工大学 Preparation method of manganese sulfide nano-rod
CN102583555A (en) * 2012-03-07 2012-07-18 陕西科技大学 Preparation method of stable state octahedron alpha-MnS microcrystal
CN107275577B (en) * 2017-06-27 2019-08-27 吉林大学 A kind of flexible electrode material and its preparation method and application
CN110474050B (en) * 2019-09-04 2021-01-05 湖南理工学院 Preparation method of doped carbon/manganese sulfide composite material
KR102235364B1 (en) 2020-10-19 2021-04-02 서경환 Process for Synthesizing of Manganese Sulfide using Electrolytic Manganese Flake and Elemental Sulfur Powder

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4676970A (en) * 1985-05-14 1987-06-30 Elkem Metals Company Method for producing metal sulfide and the product produced therefrom

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US467970A (en) * 1892-02-02 Automatic fire-extinguisher
JPS62288116A (en) * 1986-06-03 1987-12-15 Mitsui Mining & Smelting Co Ltd Production of manganese (ii) sulfide powder

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4676970A (en) * 1985-05-14 1987-06-30 Elkem Metals Company Method for producing metal sulfide and the product produced therefrom

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Vol. 12, No. 181, C-499; & JP,A,62 288 116 (MITSUI MINING & SMELTING CO LTD), 15 December 1987. *

Also Published As

Publication number Publication date
JPH11511432A (en) 1999-10-05
DK0851841T3 (en) 2001-03-26
KR100444740B1 (en) 2004-10-14
ES2154836T3 (en) 2001-04-16
CA2232592A1 (en) 1997-03-27
DE69611924D1 (en) 2001-04-05
PL325869A1 (en) 1998-08-17
JP3929071B2 (en) 2007-06-13
CN1200103A (en) 1998-11-25
CA2232592C (en) 2007-02-20
AU694893B2 (en) 1998-07-30
EP0851841B1 (en) 2001-02-28
PL183820B1 (en) 2002-07-31
EP0851841A1 (en) 1998-07-08
DE69611924T2 (en) 2001-06-21
ATE199367T1 (en) 2001-03-15
BR9610516A (en) 1999-03-30
KR19990063612A (en) 1999-07-26
SE9503322D0 (en) 1995-09-22
CN1084713C (en) 2002-05-15
AU7102296A (en) 1997-04-09
MX9802289A (en) 1998-08-30

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