CA1302048C - Process for the preparation of pure magnesium-oxide, especially suitablefor the preparation of fireproof objects - Google Patents
Process for the preparation of pure magnesium-oxide, especially suitablefor the preparation of fireproof objectsInfo
- Publication number
- CA1302048C CA1302048C CA000570534A CA570534A CA1302048C CA 1302048 C CA1302048 C CA 1302048C CA 000570534 A CA000570534 A CA 000570534A CA 570534 A CA570534 A CA 570534A CA 1302048 C CA1302048 C CA 1302048C
- Authority
- CA
- Canada
- Prior art keywords
- reaction mixture
- serpentine
- addition
- crude
- magnesium oxide
- 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.)
- Expired - Fee Related
Links
Classifications
-
- 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
- C01F5/00—Compounds of magnesium
- C01F5/26—Magnesium halides
- C01F5/30—Chlorides
-
- 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
- C01F5/00—Compounds of magnesium
- C01F5/02—Magnesia
- C01F5/06—Magnesia by thermal decomposition of magnesium compounds
- C01F5/10—Magnesia by thermal decomposition of magnesium compounds by thermal decomposition of magnesium chloride with water vapour
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
Abstract
ABSTRACT
A process for producing magnesium oxide is provided.
The process comprises reacting a starting material with hydrochloric acid to form a reaction mixture. After removal of residues from the reaction mixture, crude serpentine is added thereto forming precipitated contaminants. The precipitated contaminants are removed from the reaction mixture after which the reaction mixture is subjected to thermal decomposition thereby producing magnesium oxide and hydrogen chloride. The magnesium oxide and hydrogen chloride are subsequently separated and recovered. Suitable starting materials are selected from magnesium silicates and magnesium hydrosilicates. The process may be used to prepare relatively pure yields of magnesium oxide.
A process for producing magnesium oxide is provided.
The process comprises reacting a starting material with hydrochloric acid to form a reaction mixture. After removal of residues from the reaction mixture, crude serpentine is added thereto forming precipitated contaminants. The precipitated contaminants are removed from the reaction mixture after which the reaction mixture is subjected to thermal decomposition thereby producing magnesium oxide and hydrogen chloride. The magnesium oxide and hydrogen chloride are subsequently separated and recovered. Suitable starting materials are selected from magnesium silicates and magnesium hydrosilicates. The process may be used to prepare relatively pure yields of magnesium oxide.
Description
~3~
In one of its aspects the present invention relates to a p~ocsss for the preparation of pure magnesium oxide. In another of its aspects the present invention relates to the preparation of refractorY products .
U.S. Patent 2,398,493 teaches -the addition of calcined serpeniine to a magnesium chloride slurry produced by hydrochloric acid decomposition of serpen-tine as the precipitating agent for contaminants. However, this process has the disadvantage that the silicic acid portion of the serpentine is converted, by calcination, into a form which is more easily dissolved or suspended in the magnesium chloride slurry. The result of this is that during subsequent separation o the residue or precipitates, a larger proportion of silicic acid remair.s in the magnesium chloride brine and the S102 content in the end product is therefore higher. Further, this increased amount of amorphous or dissolved silicic acid in the magnesium chloride slurry means that the Fe(OH)3~ and other hydroxide precipitates, which arise during subsequent precipitation are more slimy a~d therefore difficult to filter. Still fur-ther, a considerable amount of energy is also required to calcine serpentine.
In process known heretofore, the compound generally used to increase the pH of the mixture and thereby precipitate the sesquioxide contaminents is magnesium oxide, usually in the form of caustic calcined magnesia. Serpentine and other similar starting materials usually have a high content of iron, sesquioxides and other contaminents. Accordingly, large amounts of precipitating compounds (eg. calcined magnesia) are usually ..
.. ;
.
~3`~
required to precipitate these undesirable compounds. Ths cost of the required amount of these precipitating compounds makes these known processes economically unattractive.
It is an object of the present invention to obviate or mitigate the above-mentioned disadvantages.
Acaordingly, the present invention provides a process for producing magnesium oxide which comprises:
(I) reacting a material selected from magnesium silicates and magneslum hydrosilicates with hydrochloric acid to form a reaction mixture;
(II) removing residue thereby formed from the reaction mixture;
(III) adding crude serpentine to the reaction mixture thereby forming precipitated comtaminants;
(IV) removing ths precipitated contaminants from the reaction mixture, (V) sub;ecting the reaction to thermal decomposition thereby producing magnesium oxida and hydrogen chloride; and (VI) separating and recovering the magnesium oxide and hydrogen ahloride.
Suitable starting materials for use in the process of the present invention include: the so-called ultra ma*itic rocks of the peridotote, dunite and harzburgite groups and the like, the transformation products thereof (which are usually known as serpentine or serpentinite), weathered products of the above-mentioned rocks, half- and by-products arising during the processing thereof, and industrial by-products and waste-products of similar composition having an MgO content of at lsast 15% by weight. For the purposes of the present invention, thsse suitable materials are embodied by the terms "serpentine" and "crude serpentine".
After decomposition of the starting silicate material with hydrochloric acid and removal of the residue therefrom, crude serpentine is added to the reaction mixture thereby increasing the pH of the reaction mixture. This results in the precipitation of oxides of iron and aluminum. It is preferable to use finely ground crude serpentine having a grain-size of less than about 1 mm, more preferably less than about O.l mm. The addition of crude serpentine as a precipitating agent ensures complete precipitation of aluminum and extensive precipitation of trivalent iron in the pH range below about 5.
If trivalent iron is present in the starting material, it may be removed upon transformation into "precipitabla"
bivalent iron. This may be accomplished by introducing air and/or another oxidizing agent into the reaction mixture under agitation and prior to the addition of the crude serpentine.
Non-limiting examples of suitable oxidizing agents include chlorine and hydrogen peroxide. If bivalent manganese is present in the starting material it may be removed upon transormation into quadravalent manganese. This may be accomplished by the addition of air and/or another o~idizing agent into the reaation mixture under agitation and prior to the addition of the crude serpentine. Accordingly, it is possible to simultaneously ~3~
transform bivalent iron and manganese into their quadravalent, "precipitable" analogs.
The addition of crude serpentine to the reaction mi~ture to precipitate contaminants may be carried out in a continuous or bulk manner.
An advantage of the process disclosed herein is that the starting material need only be broken up - i.e. no other pretreatment (such as calcining) is required.
Upon addition of the crude serpentine to the reaction mixture the pH of the reaction mixture inltially lncreases rapidly to about 4 whereby oxidation of bivalent iron to trivalent iron is favoured under these relatively acidic conditions. This in turn results in the rapid precipitation of contaminants. Subsequently, as a result o the oxidation of Fe to Fe3~, the pH value of the reaction mixture decreases slightly and then rises again. However, the pH value of the reaction mixture remains below about 5 during the precipitatlon of the con-taminants.
In a preferred embodiment, the crude serpentine is added to the reaction mixture in an amount of from about a 1.5-to about a 2.5-fold excess of the stoichiometric amount required.
For the purposes of the present invention, tha "stoichiometric amount required" is defined as the amount of crude serpentine comprising an MgO content which suffices to neutralize the acidity of the reaction mixture. The acidity of the reaction mixture is determined by the amount of free HCl present in the acidic reaction mixture and by the amount of reaction mixture in ~3~Z~
the oxidic contaminants accessible to precipita-tion. In this regard, both the oxidic contaminants which are present in the reaction mixture prior to the addition of the crude serpentine and the oxidic contaminants which are added to the reaction mixture with the crude serpentine acting as the precipitating agent, must be takan into account.
Preferably it is desirable -to maintain the temperature of the reaction mix-ture at a temperature of at least about 80C
during the addition o~ the crude serpentine.
In another preferred embodiment of the prasent invention, a pH-increasing substance is added to the reaction mixture after the addition of the crude serpentine. The addition of such a substance serves to favour the precipitation of any iron, manganese, nickel, sesguioxides and other contaminants which might remain in the reaction mixture aftex addition of the crude serpentine. Examples of suitable pH-increasing substanoes include caustic ma~nesia and flue dust (ie. a material resulting from the calcination of magnesite contalning residues of non-decomposed magnesia or magnesium carbonate). More preferably when flue dust is used as the pH-increasing substance, it is preferred to use the flue dust produced during calcination of magnesium carbonate.
When caustic magnesia is used as a pH-increasing substance in the process disclosed herein, it is preferable that the reaction mixture have a pH value of about 5 during the addition of the crude serpentine and a p~ value of from about 6 to about 7 after the addition of the caustic magnesia. The addition of the crude serpentine to the reaction mixture is continued onl~ until most of the hydroxides of iron and aluminum ~ `' ~3C~Z~9LE3 have been precipitated. Typically, precipitation which occurs by addition of crude serpentine to the reaction mixture may la~t for about four hours following which precipi-tation which occurs by addition of a pH-increasing substance to the reaction mixture may last for anothar two hours. Embodiments of the present inventio~ will now be illustrated by the following non-limiting examples.
Example 1 1730 kg of crude serpentine, containing 728 kg of MgO, 122 kg of Fe2O3, 4.66 kg of NiO and 5 kg pf CaO, were decomposed with 7330 kg of hydrochloria acid containing 1330 kg o Cl-. Abollt 710 kg of undissolved residues were separated from the reaction mixture, leaving about 8350 kg of a relatively clear reaction mixture. This clear reaction mixture, containing 713 kg of MgO, 113 kg of Fe2O3, 4.6 kg of NiO, 1330 kg of Cl- and 1.8 kg of CaO, was mixed with 674 kg of crude serpentine having a grain-size less than about 0.1 mm as the precipitating agent. During addition of the crude sexpentine, air was introduced, under intensive stirring, into the r~action mixture and the temperature maintained at a temperature above about 80C. The pH value increased to about 4 and precipitation was completed in a few hours. Ths precipitated materlal, together with the undissolved portion of the crude serpentine added as the precipitating a~ent, was separated, a filter-cake weighing 823 kg being obtained. The filter-caks contained 225 kg of MgO, 157 kg of Fe2O3, 1 kg of NiO
and 1~4 kg of CaO. The remaining reaction mixture contained 748 kg of MgO, 0.08 kg of Fe203, 5.15 kg of NiO, 1324 ky of Cl- and 3 ~3~ 4~
kg of CaO. Accordingly, the process disclosed herein was useful in producing a relatively pure yield of magnesium o~ide.
Example 2 1585 kg of crude serpentine, containing 667 kg of MgO~ 112 kg of Fe203, 4.27 kg of NiO and 4.59 kg of CaO, were decomposed with 6746 kg of hydrochloric acid ~ontaining 1220 kg of C1-.
About 625 kg of undissolved residue were separated from the reaction mixture, leaving about 7706 kg of relatively clear reaction mixture. Thus clear reaction mixture, containing 643 kg of MgO, 104 kg of Fe203, 4.20 kg of NiO, 1220 kg of Cl- and 1.8 kg of CaO, was mixed with 597 kg o* crude serpentine having a grain-size of less than about 0.1 mm as the precipitating agent.
During addition of the crude serpentine, air was introduced, under intensive stirring, into the reaction mixture and the temperature was maintained at above about 80C. The pH value increased to a value of about 4 during the reaction time o~ about 4 hours. 98 ky of flue dust was then added to the reaction mixture which resulted in the pH increasing quickly to a value of about 6.8. The said flue dust contained 82 kg of MgO, 5.20 kg of Fe2 3 and 2.60 kg of CaO. The precipitation was allowed to occur for an additional hour. The precipitated material was then separated together with the undissolved crude serpentine and caustic magnesia, resulting in a filter-cake weighing 830 kg and containing 255 kg of MgO, 145 kg of Fe203, 1.85 kg of CaO and 4.27 kg of NiO. The remaining reaction mixture ~7571 kg) contained 721 kg of MgO, <0.01 kg of Fe203, 4.25 kg of CaO, <0.01 kg of NiO and 1210 kg of Cl-.
..~ ~
In one of its aspects the present invention relates to a p~ocsss for the preparation of pure magnesium oxide. In another of its aspects the present invention relates to the preparation of refractorY products .
U.S. Patent 2,398,493 teaches -the addition of calcined serpeniine to a magnesium chloride slurry produced by hydrochloric acid decomposition of serpen-tine as the precipitating agent for contaminants. However, this process has the disadvantage that the silicic acid portion of the serpentine is converted, by calcination, into a form which is more easily dissolved or suspended in the magnesium chloride slurry. The result of this is that during subsequent separation o the residue or precipitates, a larger proportion of silicic acid remair.s in the magnesium chloride brine and the S102 content in the end product is therefore higher. Further, this increased amount of amorphous or dissolved silicic acid in the magnesium chloride slurry means that the Fe(OH)3~ and other hydroxide precipitates, which arise during subsequent precipitation are more slimy a~d therefore difficult to filter. Still fur-ther, a considerable amount of energy is also required to calcine serpentine.
In process known heretofore, the compound generally used to increase the pH of the mixture and thereby precipitate the sesquioxide contaminents is magnesium oxide, usually in the form of caustic calcined magnesia. Serpentine and other similar starting materials usually have a high content of iron, sesquioxides and other contaminents. Accordingly, large amounts of precipitating compounds (eg. calcined magnesia) are usually ..
.. ;
.
~3`~
required to precipitate these undesirable compounds. Ths cost of the required amount of these precipitating compounds makes these known processes economically unattractive.
It is an object of the present invention to obviate or mitigate the above-mentioned disadvantages.
Acaordingly, the present invention provides a process for producing magnesium oxide which comprises:
(I) reacting a material selected from magnesium silicates and magneslum hydrosilicates with hydrochloric acid to form a reaction mixture;
(II) removing residue thereby formed from the reaction mixture;
(III) adding crude serpentine to the reaction mixture thereby forming precipitated comtaminants;
(IV) removing ths precipitated contaminants from the reaction mixture, (V) sub;ecting the reaction to thermal decomposition thereby producing magnesium oxida and hydrogen chloride; and (VI) separating and recovering the magnesium oxide and hydrogen ahloride.
Suitable starting materials for use in the process of the present invention include: the so-called ultra ma*itic rocks of the peridotote, dunite and harzburgite groups and the like, the transformation products thereof (which are usually known as serpentine or serpentinite), weathered products of the above-mentioned rocks, half- and by-products arising during the processing thereof, and industrial by-products and waste-products of similar composition having an MgO content of at lsast 15% by weight. For the purposes of the present invention, thsse suitable materials are embodied by the terms "serpentine" and "crude serpentine".
After decomposition of the starting silicate material with hydrochloric acid and removal of the residue therefrom, crude serpentine is added to the reaction mixture thereby increasing the pH of the reaction mixture. This results in the precipitation of oxides of iron and aluminum. It is preferable to use finely ground crude serpentine having a grain-size of less than about 1 mm, more preferably less than about O.l mm. The addition of crude serpentine as a precipitating agent ensures complete precipitation of aluminum and extensive precipitation of trivalent iron in the pH range below about 5.
If trivalent iron is present in the starting material, it may be removed upon transformation into "precipitabla"
bivalent iron. This may be accomplished by introducing air and/or another oxidizing agent into the reaction mixture under agitation and prior to the addition of the crude serpentine.
Non-limiting examples of suitable oxidizing agents include chlorine and hydrogen peroxide. If bivalent manganese is present in the starting material it may be removed upon transormation into quadravalent manganese. This may be accomplished by the addition of air and/or another o~idizing agent into the reaation mixture under agitation and prior to the addition of the crude serpentine. Accordingly, it is possible to simultaneously ~3~
transform bivalent iron and manganese into their quadravalent, "precipitable" analogs.
The addition of crude serpentine to the reaction mi~ture to precipitate contaminants may be carried out in a continuous or bulk manner.
An advantage of the process disclosed herein is that the starting material need only be broken up - i.e. no other pretreatment (such as calcining) is required.
Upon addition of the crude serpentine to the reaction mixture the pH of the reaction mixture inltially lncreases rapidly to about 4 whereby oxidation of bivalent iron to trivalent iron is favoured under these relatively acidic conditions. This in turn results in the rapid precipitation of contaminants. Subsequently, as a result o the oxidation of Fe to Fe3~, the pH value of the reaction mixture decreases slightly and then rises again. However, the pH value of the reaction mixture remains below about 5 during the precipitatlon of the con-taminants.
In a preferred embodiment, the crude serpentine is added to the reaction mixture in an amount of from about a 1.5-to about a 2.5-fold excess of the stoichiometric amount required.
For the purposes of the present invention, tha "stoichiometric amount required" is defined as the amount of crude serpentine comprising an MgO content which suffices to neutralize the acidity of the reaction mixture. The acidity of the reaction mixture is determined by the amount of free HCl present in the acidic reaction mixture and by the amount of reaction mixture in ~3~Z~
the oxidic contaminants accessible to precipita-tion. In this regard, both the oxidic contaminants which are present in the reaction mixture prior to the addition of the crude serpentine and the oxidic contaminants which are added to the reaction mixture with the crude serpentine acting as the precipitating agent, must be takan into account.
Preferably it is desirable -to maintain the temperature of the reaction mix-ture at a temperature of at least about 80C
during the addition o~ the crude serpentine.
In another preferred embodiment of the prasent invention, a pH-increasing substance is added to the reaction mixture after the addition of the crude serpentine. The addition of such a substance serves to favour the precipitation of any iron, manganese, nickel, sesguioxides and other contaminants which might remain in the reaction mixture aftex addition of the crude serpentine. Examples of suitable pH-increasing substanoes include caustic ma~nesia and flue dust (ie. a material resulting from the calcination of magnesite contalning residues of non-decomposed magnesia or magnesium carbonate). More preferably when flue dust is used as the pH-increasing substance, it is preferred to use the flue dust produced during calcination of magnesium carbonate.
When caustic magnesia is used as a pH-increasing substance in the process disclosed herein, it is preferable that the reaction mixture have a pH value of about 5 during the addition of the crude serpentine and a p~ value of from about 6 to about 7 after the addition of the caustic magnesia. The addition of the crude serpentine to the reaction mixture is continued onl~ until most of the hydroxides of iron and aluminum ~ `' ~3C~Z~9LE3 have been precipitated. Typically, precipitation which occurs by addition of crude serpentine to the reaction mixture may la~t for about four hours following which precipi-tation which occurs by addition of a pH-increasing substance to the reaction mixture may last for anothar two hours. Embodiments of the present inventio~ will now be illustrated by the following non-limiting examples.
Example 1 1730 kg of crude serpentine, containing 728 kg of MgO, 122 kg of Fe2O3, 4.66 kg of NiO and 5 kg pf CaO, were decomposed with 7330 kg of hydrochloria acid containing 1330 kg o Cl-. Abollt 710 kg of undissolved residues were separated from the reaction mixture, leaving about 8350 kg of a relatively clear reaction mixture. This clear reaction mixture, containing 713 kg of MgO, 113 kg of Fe2O3, 4.6 kg of NiO, 1330 kg of Cl- and 1.8 kg of CaO, was mixed with 674 kg of crude serpentine having a grain-size less than about 0.1 mm as the precipitating agent. During addition of the crude sexpentine, air was introduced, under intensive stirring, into the r~action mixture and the temperature maintained at a temperature above about 80C. The pH value increased to about 4 and precipitation was completed in a few hours. Ths precipitated materlal, together with the undissolved portion of the crude serpentine added as the precipitating a~ent, was separated, a filter-cake weighing 823 kg being obtained. The filter-caks contained 225 kg of MgO, 157 kg of Fe2O3, 1 kg of NiO
and 1~4 kg of CaO. The remaining reaction mixture contained 748 kg of MgO, 0.08 kg of Fe203, 5.15 kg of NiO, 1324 ky of Cl- and 3 ~3~ 4~
kg of CaO. Accordingly, the process disclosed herein was useful in producing a relatively pure yield of magnesium o~ide.
Example 2 1585 kg of crude serpentine, containing 667 kg of MgO~ 112 kg of Fe203, 4.27 kg of NiO and 4.59 kg of CaO, were decomposed with 6746 kg of hydrochloric acid ~ontaining 1220 kg of C1-.
About 625 kg of undissolved residue were separated from the reaction mixture, leaving about 7706 kg of relatively clear reaction mixture. Thus clear reaction mixture, containing 643 kg of MgO, 104 kg of Fe203, 4.20 kg of NiO, 1220 kg of Cl- and 1.8 kg of CaO, was mixed with 597 kg o* crude serpentine having a grain-size of less than about 0.1 mm as the precipitating agent.
During addition of the crude serpentine, air was introduced, under intensive stirring, into the reaction mixture and the temperature was maintained at above about 80C. The pH value increased to a value of about 4 during the reaction time o~ about 4 hours. 98 ky of flue dust was then added to the reaction mixture which resulted in the pH increasing quickly to a value of about 6.8. The said flue dust contained 82 kg of MgO, 5.20 kg of Fe2 3 and 2.60 kg of CaO. The precipitation was allowed to occur for an additional hour. The precipitated material was then separated together with the undissolved crude serpentine and caustic magnesia, resulting in a filter-cake weighing 830 kg and containing 255 kg of MgO, 145 kg of Fe203, 1.85 kg of CaO and 4.27 kg of NiO. The remaining reaction mixture ~7571 kg) contained 721 kg of MgO, <0.01 kg of Fe203, 4.25 kg of CaO, <0.01 kg of NiO and 1210 kg of Cl-.
..~ ~
Claims (11)
1. A process for producing magnesium oxide which comprises:
(i) reacting a material selected from magnesium silicates and magnesium hydrosilicates with hydrochloric acid to form a reaction mixture;
(ii) removing residue thereby formed from the reaction mixture;
(iii) adding crude serpentine to the reaction mixture thereby forming precipitated contaminants;
(iv) removing the precipitated contaminants from the reaction mixture;
(v) subjecting the reaction mixture to thermal decomposition thereby producing magnesium oxide and hydrogen chloride; and (vi) separating and recovering the magnesium oxide and hydrogen chloride.
(i) reacting a material selected from magnesium silicates and magnesium hydrosilicates with hydrochloric acid to form a reaction mixture;
(ii) removing residue thereby formed from the reaction mixture;
(iii) adding crude serpentine to the reaction mixture thereby forming precipitated contaminants;
(iv) removing the precipitated contaminants from the reaction mixture;
(v) subjecting the reaction mixture to thermal decomposition thereby producing magnesium oxide and hydrogen chloride; and (vi) separating and recovering the magnesium oxide and hydrogen chloride.
2. The process of claim 1, wherein said material is selected from the group comprising olivine, serpentine and garnierite.
3. The process of claim 1, wherein said thermal decomposition comprises spray calcination.
4. The process of claim 1, wherein an oxidizing agent is added to the reaction mixture with agitation prior to the addition of said crude serpentine.
5. The process of claim 4, wherein said oxidizing agent is air.
6. The process of claim 1, wherein the temperature of the reaction mixture is above about 80°C during the addition of said crude serpentine.
7. The process of claims 1, 4 or 6, wherein said crude serpentine is added to the reaction mixture in an amount of from about a 1.5- to about a 2.5-fold excess of the stoichiometric amount required.
8. The process of claim 1, wherein a pH-increasing substance is added to the reaction mixture after the addition of said crude serpentine.
9. The process of claim 8, wherein said pH increasing substance is caustic magnesia.
10. The process of claim 8, wherein said pH-increasing substance is flue-dust.
11. The process of claim 9, wherein the reaction mixture has a pH value of about 5 during the addition of said crude serpentine and a pH value of from about 6 to about 7 after the addition of said caustic magnesia.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ATA1621/87 | 1987-06-26 | ||
| AT0162187A AT388392B (en) | 1987-06-26 | 1987-06-26 | METHOD FOR THE PRODUCTION OF PURE MAGNESIUM OXIDE, IN PARTICULAR FOR THE PRODUCTION OF REFRACTORY-RESISTANT PRODUCTS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1302048C true CA1302048C (en) | 1992-06-02 |
Family
ID=3517376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000570534A Expired - Fee Related CA1302048C (en) | 1987-06-26 | 1988-06-27 | Process for the preparation of pure magnesium-oxide, especially suitablefor the preparation of fireproof objects |
Country Status (18)
| Country | Link |
|---|---|
| US (1) | US4944928A (en) |
| EP (2) | EP0297088A1 (en) |
| JP (1) | JPH02500836A (en) |
| AT (2) | AT388392B (en) |
| AU (1) | AU601864B2 (en) |
| BR (1) | BR8807108A (en) |
| CA (1) | CA1302048C (en) |
| DE (1) | DE3864667D1 (en) |
| ES (1) | ES2025338B3 (en) |
| FI (1) | FI890904A0 (en) |
| GR (1) | GR3002641T3 (en) |
| HU (1) | HU204731B (en) |
| NO (1) | NO890763L (en) |
| RU (1) | RU1828450C (en) |
| TR (1) | TR25368A (en) |
| WO (1) | WO1988010236A1 (en) |
| YU (1) | YU46338B (en) |
| ZA (1) | ZA884488B (en) |
Families Citing this family (37)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT392774B (en) * | 1989-05-05 | 1991-06-10 | Veitscher Magnesitwerke Ag | FINE POWDERED MAGNESIUM HYDROXIDE AND METHOD FOR THE PRODUCTION THEREOF |
| US5286285A (en) * | 1989-05-05 | 1994-02-15 | Veitscher Magnesitwerke-Actien-Gesellschaft | Finely powdery magnesium hydroxide and a process for preparing thereof |
| NO167648C (en) * | 1989-06-09 | 1991-11-27 | Norsk Hydro As | PROCEDURE FOR MAGNESIUM CHLORIDE PREPARATION. |
| US5968081A (en) * | 1996-05-15 | 1999-10-19 | Pacesetter, Inc. | System and method for providing improved fallback response in a dual-chamber cardiac pacemaker |
| GB9611708D0 (en) * | 1996-06-05 | 1996-08-07 | Pretorius Leon E | Co-production of calcium carbonate and magnesium oxide |
| US5980854A (en) * | 1998-09-23 | 1999-11-09 | Noranda, Inc. | Method for the production of a magnesium chloride solution |
| US7212860B2 (en) | 1999-05-21 | 2007-05-01 | Cardiac Pacemakers, Inc. | Apparatus and method for pacing mode switching during atrial tachyarrhythmias |
| US7181278B2 (en) | 1999-05-21 | 2007-02-20 | Cardiac Pacemakers, Inc. | Apparatus and method for ventricular rate regularization |
| US6501988B2 (en) * | 2000-12-26 | 2002-12-31 | Cardiac Pacemakers Inc. | Apparatus and method for ventricular rate regularization with biventricular sensing |
| US8064997B2 (en) | 1999-05-21 | 2011-11-22 | Cardiac Pacemakers, Inc. | Method and apparatus for treating irregular ventricular contractions such as during atrial arrhythmia |
| US7062325B1 (en) | 1999-05-21 | 2006-06-13 | Cardiac Pacemakers Inc | Method and apparatus for treating irregular ventricular contractions such as during atrial arrhythmia |
| US6395242B1 (en) * | 1999-10-01 | 2002-05-28 | Noranda Inc. | Production of zinc oxide from complex sulfide concentrates using chloride processing |
| KR20000049740A (en) * | 2000-04-26 | 2000-08-05 | 김철우 | Making process of magnesia powder by spray roasting method |
| US7239914B2 (en) * | 2000-05-13 | 2007-07-03 | Cardiac Pacemakers, Inc. | Rate smoothing control |
| US7039461B1 (en) | 2000-05-13 | 2006-05-02 | Cardiac Pacemakers, Inc. | Cardiac pacing system for prevention of ventricular fibrillation and ventricular tachycardia episode |
| US6501987B1 (en) | 2000-05-26 | 2002-12-31 | Cardiac Pacemakers, Inc. | Rate smoothing control |
| US8512220B2 (en) | 2000-05-26 | 2013-08-20 | Cardiac Pacemakers, Inc. | Rate smoothing control |
| US6424865B1 (en) | 2000-07-13 | 2002-07-23 | Cardiac Pacemakers, Inc. | Ventricular conduction delay trending system and method |
| US6795734B2 (en) | 2000-12-26 | 2004-09-21 | Cardiac Pacemakers, Inc. | Method and apparatus for display of ventricular electrograms |
| US20020087198A1 (en) * | 2000-12-29 | 2002-07-04 | Kramer Andrew P. | Apparatus and method for ventricular rate regularization |
| US6957100B2 (en) | 2000-12-26 | 2005-10-18 | Cardiac Pacemakers, Inc. | Method and system for display of cardiac event intervals in a resynchronization pacemaker |
| US6480742B2 (en) * | 2000-12-26 | 2002-11-12 | Cardiac Pacemakers, Inc. | Pace counter isolation for cardiac resynchronization pacing |
| CA2548225A1 (en) * | 2003-05-16 | 2004-11-16 | Jaguar Nickel Inc. | A process for the recovery of value metals from material containing base metal oxides |
| CA2478516C (en) * | 2003-09-30 | 2007-12-11 | Jaguar Nickel Inc. | A process for the recovery of value metals from base metal sulfide ores |
| WO2005098062A1 (en) * | 2004-04-05 | 2005-10-20 | Hovhannes Hovhannisyan | Waste-free hydrometallurgical extraction of magnesium and other metals from rock formations of varying olivine content |
| NO20042644D0 (en) * | 2004-06-23 | 2004-06-23 | Cod Technologies As | Procedure for full utilization of olivine ingredients |
| EP1785396A1 (en) * | 2005-11-09 | 2007-05-16 | Nederlandse Organisatie voor Toegepast-Natuuurwetenschappelijk Onderzoek TNO | Process for preparing a metal hydroxide |
| US20070217981A1 (en) * | 2006-03-15 | 2007-09-20 | Van Essendelft Dirk T | Processes and systems for the sequestration of carbon dioxide utilizing effluent streams |
| JP5438687B2 (en) | 2007-12-13 | 2014-03-12 | カーディアック ペースメイカーズ， インコーポレイテッド | A system that provides unipolar detection vectors |
| JP2011525885A (en) | 2008-06-26 | 2011-09-29 | ノヴァセム リミテッド | Binder composition |
| CN101870473B (en) * | 2010-05-27 | 2012-05-02 | 浙江省地矿科技有限公司 | Comprehensive utilization method of peridotite |
| WO2012028418A1 (en) | 2010-09-02 | 2012-03-08 | Novacem Limited | Integrated process for producing compositions containing magnesium |
| CN107986304B (en) * | 2017-12-27 | 2020-02-07 | 鞍钢实业微细铝粉有限公司 | Preparation process of nano magnesium oxide |
| CN111285628B (en) * | 2020-02-17 | 2021-09-03 | 王选福 | Comprehensive utilization method of low-grade magnesite |
| CN113735146A (en) * | 2021-08-13 | 2021-12-03 | 广东邦普循环科技有限公司 | Method for recycling magnesium oxide from nickel-iron slag |
| WO2023135193A1 (en) | 2022-01-12 | 2023-07-20 | Red Stone Gmbh | Method for producing an aggregate, and aggregate |
| EP4298057A1 (en) | 2022-01-12 | 2024-01-03 | red stone GmbH | Sequestration of co2 |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2398493A (en) * | 1944-02-04 | 1946-04-16 | Int Minerals & Chem Corp | Production of magnesium chloride from serpentine |
| US2549798A (en) * | 1947-01-17 | 1951-04-24 | Edwin A Gee | Production of magnesium chloride from magnesium silicate ore |
| US3980753A (en) * | 1970-02-20 | 1976-09-14 | Veitscher Magnesitwerke-Aktiengesellschaft | Industrial process of preparing magnesia of high purity |
| AT319188B (en) * | 1970-02-20 | 1974-12-10 | Veitscher Magnesitwerke Ag | Process for the industrial production of high-purity magnesium oxide |
| DE2137573A1 (en) * | 1971-07-27 | 1973-02-08 | Oesterr Amerikan Magnesit | Dressing magnesium cpds |
| AT347403B (en) * | 1975-11-20 | 1978-12-27 | Veitscher Magnesitwerke Ag | METHOD FOR THE LARGE ENGINEERING OF MAGNESIUM OXIDE HIGH PURITY |
| AT357138B (en) * | 1978-05-08 | 1980-06-25 | Veitscher Magnesitwerke Ag | METHOD FOR THE LARGE ENGINEERING OF MAGNESIUM OXIDE HIGH PURITY |
| US4200618A (en) * | 1979-02-28 | 1980-04-29 | Engelhard Minerals & Chemicals Corporation | Preparation of magnesium chloride |
| IN151044B (en) * | 1980-04-30 | 1983-02-12 | Dalmia Inst Scient Ind Res | |
| AT367376B (en) * | 1979-12-06 | 1982-06-25 | Veitscher Magnesitwerke Ag | METHOD FOR SEPARATING IRON, ALUMINUM AND MANGANE IMPURITIES FROM SALT ACID MAGNESIUM CHLORIDE SOLUTIONS |
| DE3481413D1 (en) * | 1984-11-27 | 1990-04-05 | Sulzer Ag | METHOD FOR PRODUCING HIGH PURITY MAGNESIUM OXIDE. |
-
1987
- 1987-06-26 AT AT0162187A patent/AT388392B/en not_active IP Right Cessation
-
1988
- 1988-06-23 ZA ZA884488A patent/ZA884488B/en unknown
- 1988-06-23 ES ES88905572T patent/ES2025338B3/en not_active Expired - Lifetime
- 1988-06-23 DE DE8888905572T patent/DE3864667D1/en not_active Expired - Fee Related
- 1988-06-23 HU HU8942A patent/HU204731B/en not_active IP Right Cessation
- 1988-06-23 AT AT88905572T patent/ATE66902T1/en not_active IP Right Cessation
- 1988-06-23 WO PCT/AT1988/000048 patent/WO1988010236A1/en active IP Right Grant
- 1988-06-23 US US07/342,503 patent/US4944928A/en not_active Expired - Fee Related
- 1988-06-23 EP EP88890165A patent/EP0297088A1/en active Pending
- 1988-06-23 AU AU19583/88A patent/AU601864B2/en not_active Ceased
- 1988-06-23 EP EP88905572A patent/EP0319560B1/en not_active Expired - Lifetime
- 1988-06-23 BR BR888807108A patent/BR8807108A/en not_active Application Discontinuation
- 1988-06-23 JP JP63505214A patent/JPH02500836A/en active Granted
- 1988-06-23 YU YU122188A patent/YU46338B/en unknown
- 1988-06-24 TR TR88/0455A patent/TR25368A/en unknown
- 1988-06-27 CA CA000570534A patent/CA1302048C/en not_active Expired - Fee Related
-
1989
- 1989-02-22 NO NO89890763A patent/NO890763L/en unknown
- 1989-02-24 RU SU894613535A patent/RU1828450C/en active
- 1989-02-24 FI FI890904A patent/FI890904A0/en not_active IP Right Cessation
-
1991
- 1991-09-05 GR GR91401181T patent/GR3002641T3/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| TR25368A (en) | 1993-01-08 |
| DE3864667D1 (en) | 1991-10-10 |
| US4944928A (en) | 1990-07-31 |
| ZA884488B (en) | 1989-03-29 |
| NO890763D0 (en) | 1989-02-22 |
| AU1958388A (en) | 1989-01-19 |
| YU46338B (en) | 1993-05-28 |
| WO1988010236A1 (en) | 1988-12-29 |
| GR3002641T3 (en) | 1993-01-25 |
| EP0319560A1 (en) | 1989-06-14 |
| ATA162187A (en) | 1988-11-15 |
| EP0319560B1 (en) | 1991-09-04 |
| YU122188A (en) | 1989-10-31 |
| ATE66902T1 (en) | 1991-09-15 |
| JPH0555448B2 (en) | 1993-08-17 |
| FI890904A (en) | 1989-02-24 |
| JPH02500836A (en) | 1990-03-22 |
| RU1828450C (en) | 1993-07-15 |
| AU601864B2 (en) | 1990-09-20 |
| AT388392B (en) | 1989-06-12 |
| ES2025338B3 (en) | 1992-03-16 |
| HU204731B (en) | 1992-02-28 |
| EP0297088A1 (en) | 1988-12-28 |
| NO890763L (en) | 1989-02-22 |
| BR8807108A (en) | 1989-10-31 |
| FI890904A0 (en) | 1989-02-24 |
| HUT52740A (en) | 1990-08-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1302048C (en) | Process for the preparation of pure magnesium-oxide, especially suitablefor the preparation of fireproof objects | |
| EP1097247B1 (en) | A method for isolation and production of magnesium based products | |
| US4298379A (en) | Production of high purity and high surface area magnesium oxide | |
| US3980753A (en) | Industrial process of preparing magnesia of high purity | |
| CA1191698A (en) | Treatment of aluminous materials | |
| US20210354992A1 (en) | Production of fine grain magnesium oxide and fibrous amorphous silica from serpentinite mine tailings | |
| US4265864A (en) | Process for treating bauxite or similar raw material | |
| US4033778A (en) | Process for making magnesia | |
| CA1144341A (en) | Process for the separation of ferrous, aluminous and manganous contaminations from hydrochloric magnesium chloride solutions | |
| US4200618A (en) | Preparation of magnesium chloride | |
| KR102112572B1 (en) | Preparation of magnesium hydroxide powder from magnesite ore, and magnesium hydroxide powder obtained therefrom | |
| US3240561A (en) | Production of alumina | |
| EP0662158A1 (en) | Zirconium extraction | |
| CN103537475B (en) | With the method for comprehensive utilization of rear basic refractory | |
| KR100536261B1 (en) | Recovery method of alumina by using sulphuric acid leaching method from molten incinerator slag of sewage sludge | |
| WO1983000142A1 (en) | Magnesium oxide production | |
| JPS60500812A (en) | Magnesium oxide production | |
| Aglietti et al. | Alumina extraction from northeastern red soils of Argentina | |
| Aglietti et al. | Acid process for the extraction of aluminium from argentine weathered basalts | |
| JPS5939370B2 (en) | Production method of chromia-alumina oxide | |
| JPH08175817A (en) | Calcium aluminate hydrate and production of calcium hydroxide by using the hydrate | |
| NZ212318A (en) | Producing metallurgical grade alumina from aluminous material | |
| GB2156793A (en) | Magnesium oxide production | |
| AU2486492A (en) | Zirconium extraction | |
| JPH0348150B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |