WO2017222396A1 - Magnesium containing compositions - Google Patents
Magnesium containing compositions Download PDFInfo
- Publication number
- WO2017222396A1 WO2017222396A1 PCT/NZ2017/050086 NZ2017050086W WO2017222396A1 WO 2017222396 A1 WO2017222396 A1 WO 2017222396A1 NZ 2017050086 W NZ2017050086 W NZ 2017050086W WO 2017222396 A1 WO2017222396 A1 WO 2017222396A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- less
- olivine
- water
- olivine particles
- particles
- Prior art date
Links
- 239000011777 magnesium Substances 0.000 title claims abstract description 39
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 229910052749 magnesium Inorganic materials 0.000 title claims abstract description 37
- 239000000203 mixture Substances 0.000 title claims abstract description 7
- 239000010450 olivine Substances 0.000 claims abstract description 171
- 229910052609 olivine Inorganic materials 0.000 claims abstract description 171
- 238000000034 method Methods 0.000 claims abstract description 117
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 99
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 claims abstract description 56
- 239000000347 magnesium hydroxide Substances 0.000 claims abstract description 53
- 229910001862 magnesium hydroxide Inorganic materials 0.000 claims abstract description 53
- 235000012254 magnesium hydroxide Nutrition 0.000 claims abstract description 52
- 238000004519 manufacturing process Methods 0.000 claims abstract description 9
- 239000002245 particle Substances 0.000 claims description 196
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 90
- 239000000377 silicon dioxide Substances 0.000 claims description 37
- 230000001186 cumulative effect Effects 0.000 claims description 25
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 24
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 22
- WYTGDNHDOZPMIW-RCBQFDQVSA-N alstonine Natural products C1=CC2=C3C=CC=CC3=NC2=C2N1C[C@H]1[C@H](C)OC=C(C(=O)OC)[C@H]1C2 WYTGDNHDOZPMIW-RCBQFDQVSA-N 0.000 claims description 22
- 239000011230 binding agent Substances 0.000 claims description 22
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 12
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims description 12
- 239000003513 alkali Substances 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 8
- 239000001569 carbon dioxide Substances 0.000 claims description 6
- 230000005587 bubbling Effects 0.000 claims description 3
- 230000001376 precipitating effect Effects 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 description 28
- 239000011541 reaction mixture Substances 0.000 description 20
- 239000000654 additive Substances 0.000 description 19
- 239000000243 solution Substances 0.000 description 16
- 230000029087 digestion Effects 0.000 description 13
- 230000008569 process Effects 0.000 description 10
- 239000000463 material Substances 0.000 description 9
- 239000007787 solid Chemical group 0.000 description 9
- 239000004568 cement Substances 0.000 description 8
- 238000009826 distribution Methods 0.000 description 8
- 239000001257 hydrogen Substances 0.000 description 8
- 229910052739 hydrogen Inorganic materials 0.000 description 8
- 230000000996 additive effect Effects 0.000 description 7
- 239000011435 rock Substances 0.000 description 7
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 6
- 238000000227 grinding Methods 0.000 description 6
- 230000000979 retarding effect Effects 0.000 description 6
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 description 5
- 239000012615 aggregate Substances 0.000 description 5
- 230000008859 change Effects 0.000 description 5
- 229910001425 magnesium ion Inorganic materials 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 239000011398 Portland cement Substances 0.000 description 4
- 230000007062 hydrolysis Effects 0.000 description 4
- 238000006460 hydrolysis reaction Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 239000006228 supernatant Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000012544 monitoring process Methods 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 239000004576 sand Substances 0.000 description 3
- 229910021487 silica fume Inorganic materials 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 238000010923 batch production Methods 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 239000004035 construction material Substances 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 150000004679 hydroxides Chemical class 0.000 description 2
- -1 hydroxycarboxy acids Chemical class 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 229910052909 inorganic silicate Inorganic materials 0.000 description 2
- 235000010755 mineral Nutrition 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000013535 sea water Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000004034 viscosity adjusting agent Substances 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical class [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 1
- 235000019738 Limestone Nutrition 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- OFOBLEOULBTSOW-UHFFFAOYSA-N Propanedioic acid Natural products OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 239000002518 antifoaming agent Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000002956 ash Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- DGVMNQYBHPSIJS-UHFFFAOYSA-N dimagnesium;2,2,6,6-tetraoxido-1,3,5,7-tetraoxa-2,4,6-trisilaspiro[3.3]heptane;hydrate Chemical compound O.[Mg+2].[Mg+2].O1[Si]([O-])([O-])O[Si]21O[Si]([O-])([O-])O2 DGVMNQYBHPSIJS-UHFFFAOYSA-N 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000011152 fibreglass Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000010881 fly ash Substances 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000010903 husk Substances 0.000 description 1
- 230000036571 hydration Effects 0.000 description 1
- 238000006703 hydration reaction Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000001095 inductively coupled plasma mass spectrometry Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000004816 latex Substances 0.000 description 1
- 229920000126 latex Polymers 0.000 description 1
- 229920005610 lignin Polymers 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 235000014380 magnesium carbonate Nutrition 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid Chemical compound OC(=O)\C=C/C(O)=O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 description 1
- 239000011976 maleic acid Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Chemical class 0.000 description 1
- 239000004005 microsphere Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000003921 particle size analysis Methods 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000008262 pumice Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000010517 secondary reaction Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 230000009974 thixotropic effect Effects 0.000 description 1
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
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
- C01F5/14—Magnesium hydroxide
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
- C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
- C01B3/06—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
- C01B33/22—Magnesium silicates
-
- 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
- C01F5/08—Magnesia by thermal decomposition of magnesium compounds by calcining magnesium hydroxide
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/08—Ferroso-ferric oxide [Fe3O4]
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/18—Waste materials; Refuse organic
- C04B18/24—Vegetable refuse, e.g. rice husks, maize-ear refuse; Cellulosic materials, e.g. paper, cork
- C04B18/248—Vegetable refuse, e.g. rice husks, maize-ear refuse; Cellulosic materials, e.g. paper, cork from specific plants, e.g. hemp fibres
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B22/00—Use of inorganic materials as active ingredients for mortars, concrete or artificial stone, e.g. accelerators, shrinkage compensating agents
- C04B22/06—Oxides, Hydroxides
- C04B22/066—Magnesia; Magnesium hydroxide
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/10—Lime cements or magnesium oxide cements
- C04B28/105—Magnesium oxide or magnesium carbonate cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/30—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing magnesium cements or similar cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B9/00—Magnesium cements or similar cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B9/00—Magnesium cements or similar cements
- C04B9/20—Manufacture, e.g. preparing the batches
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
- Y02P40/18—Carbon capture and storage [CCS]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Definitions
- the present invention generally relates to magnesium containing compositions, and their use in the production of concrete.
- MgO magnesite
- MgO is also commonly obtained from seawater.
- Mg(OH)2 derived from the seawater, is calcined at temperatures of approximately 400°C, compared to 700°C to 1000°C for MgCOs.
- Serpentine has been suggested as an alternative source of both MgO and silica. Weathering of serpentine produces both MgO and silica via a slow process occurring naturally over many years or even millennia. Hrsak et a/. (2005) state that serpentine heated to 660°C will break down to yield a mixture of free oxides of MgO and S1O2. MgO derived from serpentine is not currently commercially available.
- the present inventors have developed an alternative process for producing Mg(OH)2.
- This material may be used to produce a magnesium-based concrete.
- the process results in reduced manufacturing-related carbon dioxide emissions and lower energy consumption when compared to the production of conventional calcium-based cement.
- the invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than ⁇ .
- the temperature is 90°C or less. More preferably the temperature is 50°C or less.
- the olivine particles have a mean particle size of less than 20 ⁇ .
- the invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m 2 /kg.
- the temperature is 90°C or less. More preferably the temperature is 50°C or less.
- the olivine particles have a cumulative specific surface area of at least
- the water has a pH from 5 to 9. In some embodiments the water has a pH from 6 to 8. In some embodiments the water has a pH from 5 to 7. In some embodiments the water has a pH of 5. In some embodiments the water has a pH of 6. In some embodiments the water has a pH of 7.
- a method of the invention further produces hydrogen gas. In some embodiments a method of the invention further produces magnetite. In some embodiments a method of the invention further produces silica dioxide.
- a method of the invention further comprises precipitating the Mg(OH)2.
- the Mg(OH)2 is precipitated using an alkali solution.
- the method of the invention further comprises recovering the precipitated Mg(OH)2.
- the method of the invention further comprises dehydrating the precipitated Mg(OH)2 to produce MgO.
- the method of the invention further comprises combining the MgO obtained by a method of the invention with silica to produce a magnesium silica binder.
- the silica is amorphous.
- the silica has a similar fineness to Portland cement.
- the silica particles have a diameter of less than ⁇ , preferably less than 10 ⁇ .
- the silica particles have a surface area of 300-400m 2 /kg.
- the method of the invention further comprises combining the MgO obtained by a method of the invention with quartz to produce a magnesium silica binder.
- the quartz particles have a diameter of less than ⁇ .
- the method of the invention further comprises using the magnesium silica binder obtained by a method of the invention to produce concrete.
- the Mg(OH)2 forms a layer on the olivine particles.
- the olivine particles further comprise a layer of serpentine beneath the Mg(OH)2 layer.
- Mg(OH)2 forms a layer on serpentine particles.
- the invention provides Mg(OH)2 produced by a method of the invention.
- the invention provides a magnesium silica binder produced by a method of the invention.
- the invention relates to the use of Mg(OH)2 produced according to the invention to produce concrete.
- the invention relates to the use of a magnesium silica binder according to the invention to produce concrete.
- the invention provides a method of making concrete, comprising mixing the magnesium silica binder of the invention with aggregate and water.
- the invention provides concrete, when made by a method of the invention.
- the invention provides a concrete premix comprising the binder of the invention and aggregate, and optionally comprising additional chemical and/or mineral admixtures typically used in the production of concrete.
- additional chemical and/or mineral admixtures are selected from plasticisers, set retardants, set accelerants, viscosity modifiers, water reducing agents, and air entraining agents.
- the invention provides a method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than ⁇ .
- the invention provides a method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m 2 /kg.
- the invention provides a method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than ⁇ .
- the invention provides a method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m 2 /kg.
- the invention provides a method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than ⁇ .
- the invention provides a method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m 2 /kg.
- the invention provides a method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than ⁇ .
- the invention provides a method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
- This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
- Figure 1 shows the particle size distribution for olivine particles ground using a plate mill, a ring mill for 20 seconds, a ring mill for one minute or a horizontal rod mill, wherein the particle size is expressed as a percentage mass passing;
- Figure 2 shows an embodiment of the overall process of the invention, including the digestion of olivine, the recovery of the digestion products, and their use to make a magnesium cement;
- Figure 3 shows the pH of the reaction mixture after olivine was digested for 3 hours at 20°C and 50°C;
- Figure 4 shows the change in pH of the reaction mixture over time when olivine was digested for 168 hours at 20°C and 50°C
- Figure 5 shows the change in magnesium concentration in the reaction mixture over time when olivine was digested at 20°C and 50°C;
- Figure 6 shows the change in silica concentration in the reaction mixture over time when olivine was digested at 50°C
- Figure 7 shows the relationship between dissolved silica in the reaction mixture and pH at 20°C over time
- Figure 8 shows hydrogen concentration over time when olivine is digested at a) 20°C and b) 50°C;
- Figure 9 shows particle size distribution for olivine pa rticles ground using a plate mill, a ring mill for 20 seconds, a ring mill for one minute or a horizonta l rod mill, expressed as specific surface area (m 2 /kg) .
- Olivine occurs naturally in ultramafic basalt rock. When exposed to subsurface water and/or to the elements, the olivine is subject to alteration, a nd in particular hydrolysis. In natural environments the hydrolysis of olivine typically occurs over a range of temperatures and pressures and is commonly thought to take thousands of yea rs. The present inventors have surprisingly determined that if olivine is ground very finely the reaction can be rapid even at low temperatures.
- the invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 10% of the olivine particles have a mean particle size of less than 10 ⁇ - ⁇ .
- the invention also provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m 2 /kg.
- the solid residue may comprise one or more of serpentine, magnetite (Fe30 4 ), unreacted olivine and precipitated Mg(OH) 2 .
- the olivine suitable for use in the method of the invention includes ultramafic or mafic (e.g ., basalt) rock containing a suitable concentration of olivine.
- the olivine is preferably predominantly magnesium rich (i.e., forsteritic in character).
- the ultramafic or mafic rock contains at least 10% olivine by mass.
- the ultramafic or mafic rock contains at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, or at least 80% olivine by mass.
- the ultramafic or mafic rock contains 30%-80% olivine by mass.
- the ultramafic or mafic rock contains at least 40% olivine by mass.
- a person skilled in the art can analyse a sample of an ultramafic or mafic rock to determine the percentage by mass of olivine using, for example, X-ray diffraction.
- Olivine is mined in many locations around the world.
- the mined olivine may be subject to a preliminary processing step to reduce the size of the mined material.
- the olivine useful in the invention has an initial particle size of 20-50mm. Any suitable apparatus can be used to reduce the initial particle size of the olivine to provide the mean particle sizes or cumulative specific surface area useful in the invention.
- Suitable apparatus include, but are not limited to, a plate mill, a ring mill, a horizontal rod mill, a jet mill, a ball mill and a vertical rolling mill. The person skilled in the art will appreciate how to operate these apparatus to obtain particles that are suitable for use in the invention.
- Particle size can be determined by mass or by volume.
- mean particle size is calculated as Zxirrii, where m, is the fraction by mass at a given size Xi .
- a sample is subject to multiple analyses and the average result determined.
- suitable means for analysing particle size include, but are not limited to, laser particle size analysis, scanning electron microscope imaging and other optical techniques.
- the term "specific surface area” of particles means the area of the exterior surface of the particles. Specific surface area may be calculated by assuming that the particles are more or less spherical, and calculating the surface area based on particle size. Specific surface area may be calculated as surface area per mass, for example as surface area per kg of material.
- the term "cumulative surface area” as used herein takes into account the particle size distribution as well as individual surface area . Cumulative surface area can be calculated by adding together the specific surface area of the individual size fractions.
- the olivine particles have a mean particle size of less than ⁇ .
- the olivine particles may have a mean particle size of less than 75 ⁇ , less than 70 ⁇ - ⁇ , less than 65 ⁇ , less than ⁇ , less than 55 ⁇ , less than 50 ⁇ , less than 45 ⁇ , less than 40 ⁇ - ⁇ , less than 35 ⁇ , less than 30 ⁇ , less than 25 ⁇ , less than 20 ⁇ , less than ⁇ , less than ⁇ , less than 5 ⁇ , or less than ⁇ ⁇ .
- the olivine particles have a mean particle size of less than 40 ⁇ . Even more preferably, the olivine particles have a mean particle size of less than 20 ⁇ .
- At least 10% of the olivine particles have a mean particle size of less than ⁇ .
- at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% or at least 100% of the olivine particles have mean particle size of less than ⁇ .
- Preferably at least 20% of the olivine particles have mean particle size of less than ⁇ .
- at least 30% of the olivine particles have mean particle size of less than ⁇ .
- the olivine particles have a cumulative specific surface area of at least 18.2m 2 /kg. in some embodiments the olivine particles have a cumulative specific surface area of at least 150m 2 /kg, at least 250m 2 /kg, at least 500m 2 /kg, at least 750m 2 /kg, at least 1000m 2 /kg, at least 1250m 2 /kg, at least 1500m 2 /kg or at least 1800m 2 /kg.
- the olivine particles have a cumulative specific surface area of at least 45m 2 /kg. Even more preferably, the olivine particles have a cumulative specific surface area of at least 90m 2 /kg.
- Water is used to digest the olivine particles.
- the water has a pH of from 5 to 9.
- the water has a pH of from 6 to 8.5.
- the water has a pH of 7.
- Those persons skilled in the art can adjust the pH of the water using an appropriate acid or base.
- the pH of the water is adjusted by dissolution of carbon dioxide.
- the method comprises mixing the olivine particles with water.
- the temperature of the reaction mixture of olivine particles and water will typically be less than 200°C.
- the temperature may be less than 180°C, less than 160°C, less than 140°C, less than 120°C, less than 100°C, less than 90°C, less than 60°C, less than 40°C or less than 20°C.
- the temperature may be 50°C.
- the olivine is mixed with cold water and the reaction mixture heated to the required
- the olivine can be mixed with water that is already heated.
- the ratio of water to olivine particles is from 1000: 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is from 100 : 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is from 10 : 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is 5 : 1, 2: 1, 1 : 2, or 1 : 5. In some embodiments the ratio of water to olivine particles is 1 : 1.
- the method comprises digesting olivine particles with water at a temperature of 150°C or less, wherein the olivine particles have a mean particle size of less than ⁇ , and wherein at least 30% of the olivine particles have a mean particle size of less than 10 ⁇ - ⁇ .
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 40 ⁇ - ⁇ , and wherein at least 50% of the olivine particles have a mean particle size of less than 10 ⁇ - ⁇ .
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 40 ⁇ - ⁇ , and wherein at least 30% of the olivine particles have a mean particle size of less than ⁇ .
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 30 ⁇ , and wherein at least 30% of the olivine particles have a mean particle size of less than ⁇ .
- the method comprises digesting olivine particles with water at a temperature of 150°C or less, wherein the olivine particles have a cumulative specific surface area of at least 66 m 2 /kg.
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 103m 2 /kg.
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 78m 2 /kg.
- the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 87m 2 /kg.
- the pH of the water is preferably from 6 to 8.5. In the particular embodiments above, the ratio of water to olivine particles is preferably 2 : 1.
- the process is performed in one or more reaction vessels.
- the reaction vessel is a stainless steel or fibreglass tank. In some embodiments the size of the reaction vessel may be 20 to 100m 3 .
- the process is a batch process.
- the invention is not limited thereto and other embodiments, in which the process is a continuous process, are also contemplated.
- the reaction mixture of olivine and water may be agitated.
- agitation is the result of stirring, a bubbling system, and/or the use of a pump or filter.
- air, carbon dioxide, or a mixture thereof are bubbled through the reaction mixture of olivine and water.
- currents can be created during the digestion process by feeding a slurry of olivine and water into the bottom and/or top of the reaction vessel.
- olivine is digested with water until at least 20%, at least 50% or at least 80% of the olivine has reacted.
- One method for following progression of the digestion comprises monitoring the pH of the reaction mixture of olivine and water.
- olivine is digested with water until the pH of the reaction mixture has increased to 9.5 and then decreased by at least 0.5 pH.
- Another method for determining whether the digestion has sufficiently progressed comprises monitoring the rate at which hydrogen gas is produced.
- olivine is digested with water until the rate of hydrogen production increases less than 10%/day (or equivalent for different time steps).
- Another method for determining whether the digestion has sufficiently progressed comprises measuring the concentration of magnesium ions in the reaction mixture. In some embodiments the digestion continues for about one to about three days.
- Another method for determining whether the digestion has sufficiently progressed comprises monitoring the change in density as the reaction proceeds.
- Olivine has a density of approximately 3.3 g/cm 3 and serpentine (i.e. the hydrolysis product of olivine) has a density of approximately 2.5-2.6 g/cm 3 .
- serpentine i.e. the hydrolysis product of olivine
- this method and/or others may be applied to both a batch process and a continuous process.
- Digesting olivine with water produces Mg(OH)2 in solution in the reaction mixture.
- the Mg(OH)2 can be precipitated by any conventional means.
- the Mg(OH)2 can be precipitated using an aqueous alkali solution with a pH greater than approximately 10.4.
- Suitable alkali solutions include but are not limited to aqueous solutions of alkali metal hydroxides, for example 0.1M solutions of NaOH or KOH.
- the supernatant containing Mg(OH)2 is continuously removed from the initial reaction vessel into a second reaction vessel and reacted with an aqueous alkali solution.
- the precipitated Mg(OH)2 may then be recovered from the second reaction vessel.
- olivine and/or serpentine particles are removed from the supernatant.
- Suitable means include, but are not limited to, a filter or a settling tank.
- the recovered Mg(OH)2 is dehydrated to MgO.
- the recovered Mg(OH)2 is heated, preferably to 300°C to 400°C.
- the recovered Mg(OH)2 may be subject to mechanical processing, such as centrifugation, before being heated.
- the aqueous alkali solution can be processed to obtain alkali hydroxides and water.
- the alkali hydroxides obtained from the aqueous alkali solution may be used to maintain the pH in the second reaction vessel.
- the water obtained from the aqueous alkali solution is used to digest further olivine with the method of the invention.
- the Mg(OH)2 can be precipitated in the initial reaction vessel.
- the Mg(OH)2 may not readily be separated from the residual solid. Accordingly, if separated Mg(OH)2 is required, the Mg(OH)2 concentration in the reaction mixture should be monitored so that the supernatant can be removed before precipitation occurs.
- the pH of the primary reaction vessel is maintained below approximately 10.5.
- the pH can be kept below 10.5 by adding water to the reaction vessel.
- the solid residue produced by the method may be separated from the liquid component of the reaction mixture by, for example, filtering the reaction mixture.
- the solid residue is separated from the liquid component by vacuum filtration. Other methods of separating the solid residue of the reaction mixture from the liquid component may also be used, such as a phase separator, a hydrocyclone, extractor, or centrifuge.
- the solid residue may be separated from the liquid component by gravity settlement.
- the hydrogen gas produced by the method is collected.
- the method of the invention is carried out in a sealed reaction vessel.
- the method of the invention is carried out under reduced pressure.
- these embodiments simplify recovery of the hydrogen gas.
- the person skilled in the art can readily envisage alternative methods of recovery.
- the collected hydrogen gas may be used as an energy source either in its own right, or to supplement the energy requirements of the process.
- Serpentine and magnetite reaction products may also be recovered from the solid residue.
- the use of larger olivine particles in the method of the invention results in particles comprising a core of unreacted olivine surrounded by a layer of serpentine. In some embodiments these particles are recovered, reground and used as feedstock for the method of the invention.
- the serpentine or olivine/serpentine particles may also have a layer of Mg(OH)2.
- the magnetite reaction products may have an outer layer of Mg(OH)2.
- these particles with a layer of Mg(OH)2 may be heated to dehydrate the Mg(OH)2, leaving a MgO layer on the surface of the particle.
- the MgO obtained from the method of the invention can be combined with a finely divided amorphous silica to produce a construction material.
- the construction material is a magnesium silica binder.
- the ratio of silica to MgO is from 70: 30 to 30 : 70, preferably from 60:40 to 40 : 60.
- the silica can be from a variety of sources including but not limited to fly ash, ground granulated blast furnace slag, naturally occurring amorphous silica (pumice for example) and silica fume.
- the silica has a particle size similar to or smaller than the MgO.
- the MgO produced by the method of the invention can be used to prepare concrete.
- concrete is prepared by mixing the MgO produced by the invention with aggregate, silica, sand and water.
- the ratio of water to MgO is from 0.3 to 33 by mass. In some embodiments the ratio of water to MgO is from 1 to 3.3 by mass.
- the magnesium silica binder of the invention can be used to prepare concrete.
- the person skilled in the art is familiar with methods for making concrete from binders, and the magnesium silica binder of the invention can be used in a manner comparable to traditional Portland cement.
- the person skilled in the art will be able to select the appropriate concrete preparation method depending on the particular application and the desired result.
- concrete is prepared by mixing the magnesium silica binder of the invention with aggregate, sand and water.
- the ratio of water to magnesium silica binder is 0.1 to 10.
- the ratio of water to magnesium silica binder is 0.3 to 1.
- a concrete premix can be prepared by mixing the MgO produced by a method of the invention with aggregate, silica and sand.
- the concrete premix may further comprise a set retarding additive.
- set retarding additive refers to an additive that retards the setting of concrete.
- suitable set retarding additives include, but are not limited to, ammonium, alkali metals, alkaline earth metals, metal salts of sulfoalkylated lignins, organic acids (e.g., hydroxycarboxy acids), copolymers that comprise acrylic acid or maleic acid, and combinations thereof.
- the set retarding additive is included in the concrete premix in an amount sufficient to provide the desired set retardation.
- the person skilled in the art will be able to select the appropriate amount of the set retarding additive to include for a chosen application.
- the set retarding additive may be present in the concrete premix an amount in the range of 0.1% to 5% (by weight).
- additives may be added to the concrete premix as considered appropriate by the person skilled in the art.
- additives include, but are not limited to, viscosity modifiers, water reducing agents, air entraining agents, strength- retrogression additives, set accelerators, weighting agents, lightweight additives, gas- generating additives, mechanical property enhancing additives, lost-circulation materials, filtration-control additives, dispersants, fluid loss control additives, defoaming agents, foaming agents, oil-swellable particles, water-swellable particles, thixotropic additives, and combinations thereof.
- additives include limestone, salts, fibers, hydratable clays, microspheres, rice husk ash, elastomers, elastomeric particles, resins, latex, combinations thereof, and the like.
- ground limestone is used to bulk up the concrete premix and control particle distribution. The person skilled in the art can determine the type and amount of additive useful for a particular application and desired result.
- Figure 2 shows an embodiment of the overall reaction process.
- it shows the digestion of olivine with water in a primary reaction vessel to produce serpentine, Mg(OH)2, magnetite and hydrogen gas.
- the supernatant is mixed with an alkali solution in a secondary reaction vessel to precipitate the Mg(OH)2. The precipitated
- Mg(OH)2 is then heated to produce MgO and combined with silica for use in producing a magnesium based cement.
- Figure 2 also shows that serpentine may be recovered, and that some of the solid particles may have a layer of Mg(OH)2. The particles with a layer of Mg(OH)2 may be heated to produce a magnesium based cement.
- FIG. 2 further shows that the hydrogen gas produced by the digestion can be collected.
- the hydrogen gas may be used to provide heat for the dehydration of Mg(OH)2.
- Olivine was sourced from Dunn Mountain, New Zealand. All other chemicals and reagents were standard laboratory supplies.
- the weathering products were removed from the exterior of the olivine samples prior to grinding.
- the olivine samples were initially prepared in a jaw crusher resulting in material with a maximum particle size of less than 2 mm.
- Four samples were then ground using either a plate mill, 20 seconds in a ring mill, 1 minute in a ring mill or 8 hours in a horizontal rod mill with a load capacity of 6L.
- the olivine had to be processed in batches. The individual batches were blended to create a homogenous material for analysis. For each batch, the ring mill was charged with approximately 50g of olivine. Two sizes of 106 ⁇ and 42 ⁇ were obtained by operating the machine for 20 seconds and 1 minute respectively.
- the plate mill was set with a distance between the plates equal to approximately 0.11mm.
- the olivine was added to the hopper at a rate of approximately 1 kg per minute.
- the average particle size was approximately 152 m.
- the rod mill was charged with approximately 10 kg of olivine.
- the mill containing the steel rods rotated about the horizontal axis at a speed of approximately 30 revolutions per minute.
- the olivine was left in the rod mill for 8 hours resulting in an average fineness of approximately 41 m.
- the average particle size for the different samples is set out in Table 2.
- Mean calculated Zxirrii, where m, is the fraction by mass at a given size x
- m is the fraction by mass at a given size x
- Figure 1 The particle size distribution, expressed as a percentage mass passing, is shown in Figure 1 and appears consistent with average particle sizes presented in Table 2.
- olivine samples were prepared for each level of grinding, temperature and duration. 3g of olivine and 6 ml of de-ionized water were added to 12 ml glass bottles and sealed with a septum lid to allow for extraction and analysis of the gas. The hydration of olivine was evaluated after 3 hours, 1 day, 3 days and 7 days at temperatures of 20°C and 50°C. The gas present in the head space above the olivine and water sample was drawn off with a syringe and analysed with a gas chromatograph to determine the hydrogen, oxygen, nitrogen and carbon dioxide concentrations. A summary of the specimen test conditions is provided in Table 3.
- reaction mixture Approximately 4 ml was filtered for ICPMS analysis.
- the magnesium and silica concentrations in the reaction mixture were at a maximum 3 hours after mixing and gradually decreased over the exposure period.
- the 20°C samples consistently had higher concentrations than 50°C samples for the comparable particle size.
- the change in magnesium concentration over the exposure period is provided in Figure 5 while the pronounced decrease in silica concentration for 20°C is show in Figure 6.
- the overall production of magnesium can be inferred from the accumulation of hydrogen in the head space of the container which is shown as an increase in H2 concentration in Figure 8.
- Table 2 A summary of the average particle size data for the four levels of grinding is shown above in Table 2. It can be seen from Table 2 that there is very little difference in either the mean or median particle size for the 1 minute ring mill or 8 hour rod mill while there is a clear difference between the plate mill, 20 second ring mill and the remaining two.
- Each sample had an average particle size of 41 ⁇ .
- Each sample was added to 80 ml of either soda water (CO2 injected) or deionized (DI) water.
- the soda water was a commercially available, off the shelf product, initially pressurized to approximately 2 bar.
- the pH of the soda water was approximately 5.
- Sample Paerated contained deionized water with air continuously bubbled through at a rate of approximately 1 l/min.
- reaction vessels were un-sealed and the concentration of dissolved CO2 would be expected to decrease with time for sample P5.
- Table 4 shows the concentration of magnesium ions in solution increased for the reaction in soda water and, to a lesser extent, the aerated reaction, compared with the reaction in deionized water. The highest level of dissolved magnesium was measured for the soda water solution.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Ceramic Engineering (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Botany (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Civil Engineering (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Combustion & Propulsion (AREA)
- Manufacturing & Machinery (AREA)
- Silicates, Zeolites, And Molecular Sieves (AREA)
Abstract
Disclosed are magnesium containing compositions and their use in the production of concrete. In particular, disclosed are methods of producing Mg(OH)2 comprising digesting olivine with water.
Description
Magnesium containing compositions
TECHNICAL FIELD
The present invention generally relates to magnesium containing compositions, and their use in the production of concrete.
BACKGROUND ART
While traditional calcium-based cements are well known, the development of a magnesium binder that can compete with Portland cement is fairly recent. Wei et al. (2006) developed one of the first successful magnesium-silica pastes by combining MgO (produced at 800°C) with a microsilica (and some unspecified additives) to achieve compressive strengths comparable to those of Portland cement.
Most commercially available reactive MgO is obtained from the calcination of magnesite (MgC03) at around 700°C. MgO is also commonly obtained from seawater. Mg(OH)2, derived from the seawater, is calcined at temperatures of approximately 400°C, compared to 700°C to 1000°C for MgCOs.
Serpentine has been suggested as an alternative source of both MgO and silica. Weathering of serpentine produces both MgO and silica via a slow process occurring naturally over many years or even millennia. Hrsak et a/. (2005) state that serpentine heated to 660°C will break down to yield a mixture of free oxides of MgO and S1O2. MgO derived from serpentine is not currently commercially available.
The known art methods for producing a magnesium-based cement system can be summarized as
1. MgCOs + Heat (> 700°C)→ MgO + CO2
2. MgO + Silica + Water→ Magnesium Cement (Magnesium silicate hydrate)
3. Mg2+ + CO2 → Magnesium Cement (MgC03).
Accordingly, it is an object of the present invention to go some way to avoiding the above disadvantages; and/or to at least provide the public with a useful choice.
Other objects of the invention may become apparent from the following description which is given by way of example only.
Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date.
SUMMARY OF THE INVENTION
The present inventors have developed an alternative process for producing Mg(OH)2. This material may be used to produce a magnesium-based concrete. In some embodiments the process results in reduced manufacturing-related carbon dioxide emissions and lower energy consumption when compared to the production of conventional calcium-based cement.
In a first aspect, the invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
Preferably, the temperature is 90°C or less. More preferably the temperature is 50°C or less.
Preferably, the olivine particles have a mean particle size of less than 20μηι.
Preferably, at least 30% of the olivine particles have a mean particle size of less than ΙΟμηη. In a second aspect, the invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
Preferably, the temperature is 90°C or less. More preferably the temperature is 50°C or less.
Preferably, the olivine particles have a cumulative specific surface area of at least
150m2/kg.
Preferably, the water has a pH from 5 to 9. In some embodiments the water has a pH from 6 to 8. In some embodiments the water has a pH from 5 to 7. In some embodiments the
water has a pH of 5. In some embodiments the water has a pH of 6. In some embodiments the water has a pH of 7.
In some embodiments a method of the invention further produces hydrogen gas. In some embodiments a method of the invention further produces magnetite. In some embodiments a method of the invention further produces silica dioxide.
In some embodiments a method of the invention further comprises precipitating the Mg(OH)2. In some embodiments the Mg(OH)2 is precipitated using an alkali solution.
In some embodiments the method of the invention further comprises recovering the precipitated Mg(OH)2.
In some embodiments the method of the invention further comprises dehydrating the precipitated Mg(OH)2 to produce MgO.
In some embodiments the method of the invention further comprises combining the MgO obtained by a method of the invention with silica to produce a magnesium silica binder. In some embodiments the silica is amorphous. In some embodiments the silica has a similar fineness to Portland cement. In some embodiments the silica particles have a diameter of less than ΙΟΟμηη, preferably less than 10 μηη. In some embodiments the silica particles have a surface area of 300-400m2/kg.
In some embodiments the method of the invention further comprises combining the MgO obtained by a method of the invention with quartz to produce a magnesium silica binder. In some embodiments the quartz particles have a diameter of less than Ιμηη.
In some embodiments the method of the invention further comprises using the magnesium silica binder obtained by a method of the invention to produce concrete.
In some embodiments the Mg(OH)2 forms a layer on the olivine particles. In some embodiments the olivine particles further comprise a layer of serpentine beneath the Mg(OH)2 layer. In some embodiments Mg(OH)2 forms a layer on serpentine particles.
In a third aspect, the invention provides Mg(OH)2 produced by a method of the invention. In a fourth aspect, the invention provides a magnesium silica binder produced by a method of the invention.
In a fifth aspect, the invention relates to the use of Mg(OH)2 produced according to the invention to produce concrete.
In a sixth aspect, the invention relates to the use of a magnesium silica binder according to the invention to produce concrete.
In a seventh aspect, the invention provides a method of making concrete, comprising mixing the magnesium silica binder of the invention with aggregate and water.
In an eighth aspect, the invention provides concrete, when made by a method of the invention.
In a ninth aspect, the invention provides a concrete premix comprising the binder of the invention and aggregate, and optionally comprising additional chemical and/or mineral admixtures typically used in the production of concrete. For example, in some embodiments the additional chemical and/or mineral admixtures are selected from plasticisers, set retardants, set accelerants, viscosity modifiers, water reducing agents, and air entraining agents.
In a tenth aspect, the invention provides a method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
In an eleventh aspect, the invention provides a method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
In a twelfth aspect, the invention provides a method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
In a thirteenth aspect, the invention provides a method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
In a fourteenth aspect, the invention provides a method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
In a fifteenth aspect, the invention provides a method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
In a sixteenth aspect, the invention provides a method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
In a seventeenth aspect, the invention provides a method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
Other preferred embodiments of the tenth to seventeenth aspects of the invention incorporate features of the various preferred embodiments of the first and second aspects of the invention described herein.
This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
In addition, where features or aspects of the invention are described in terms of Markush groups, those persons skilled in the art will appreciate that the invention is also thereby described in terms of any individual member or subgroup of members of the Markush group.
As used herein "(s)" following a noun means the plural and/or singular forms of the noun. As used herein the term "and/or" means "and" or "or" or both.
The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.
It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner.
Although the present invention is broadly as defined above, those persons skilled in the art will appreciate that the invention is not limited thereto and that the invention also includes embodiments of which the following description gives examples.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described with reference to the Figures in which :
Figure 1 shows the particle size distribution for olivine particles ground using a plate mill, a ring mill for 20 seconds, a ring mill for one minute or a horizontal rod mill, wherein the particle size is expressed as a percentage mass passing;
Figure 2 shows an embodiment of the overall process of the invention, including the digestion of olivine, the recovery of the digestion products, and their use to make a magnesium cement;
Figure 3 shows the pH of the reaction mixture after olivine was digested for 3 hours at 20°C and 50°C;
Figure 4 shows the change in pH of the reaction mixture over time when olivine was digested for 168 hours at 20°C and 50°C;
Figure 5 shows the change in magnesium concentration in the reaction mixture over time when olivine was digested at 20°C and 50°C;
Figure 6 shows the change in silica concentration in the reaction mixture over time when olivine was digested at 50°C;
Figure 7 shows the relationship between dissolved silica in the reaction mixture and pH at 20°C over time;
Figure 8 shows hydrogen concentration over time when olivine is digested at a) 20°C and b) 50°C;
Figure 9 shows particle size distribution for olivine pa rticles ground using a plate mill, a ring mill for 20 seconds, a ring mill for one minute or a horizonta l rod mill, expressed as specific surface area (m2/kg) .
DETAILED DESCRIPTION OF THE INVENTION
Olivine occurs naturally in ultramafic basalt rock. When exposed to subsurface water and/or to the elements, the olivine is subject to alteration, a nd in particular hydrolysis. In natural environments the hydrolysis of olivine typically occurs over a range of temperatures and pressures and is commonly thought to take thousands of yea rs. The present inventors have surprisingly determined that if olivine is ground very finely the reaction can be rapid even at low temperatures.
The reactions occurring during the low temperature hydrolysis of olivine are summarized in Table 1.
Table 1
1 1 2 2Mg2Si04 + 3H20→ Mg3Si205(OH)4 + Mg2+ + 2(OH")
4 Mg2+ + 2(OH")→ Mg(OH)2 (or a wide va riety of
3 2
5 (oxy) hyd roxides)
6 3 7 3Fe2Si04 + 2H20→ 2Fe304 + 3Si02 + 2H2
(Mgo.88Feo. i2)2Si04 + 1.34H20 = 0.5Mg3Si2O5(OH)4 + 0.08Fe3O4 +
A
0.26Mg(OH)2 + 0.08H2
The invention provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than 10μη-ι.
The invention also provides a method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
Other products of the process may include hydrogen gas, and a solid residue. The solid residue may comprise one or more of serpentine, magnetite (Fe304), unreacted olivine and precipitated Mg(OH)2.
The olivine suitable for use in the method of the invention includes ultramafic or mafic (e.g ., basalt) rock containing a suitable concentration of olivine. In those embodiments wherein the method is directed to producing Mg(OH)2, MgO, a magnesium silica binder or concrete the olivine is preferably predominantly magnesium rich (i.e., forsteritic in character). In those embodiments wherein the method is directed to producing hydrogen gas, magnetite, silica dioxide or serpentine the person skilled in the art will appreciate that other forms of olivine may be preferred. In some embodiments the ultramafic or mafic rock contains at least 10% olivine by mass. For example, in some embodiments the ultramafic or mafic rock contains at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, or at least 80% olivine by mass. In some embodiments the ultramafic or mafic rock contains 30%-80% olivine by mass. In some embodiments the ultramafic or mafic rock contains at least 40% olivine by mass. A person skilled in the art can analyse a sample of an ultramafic or mafic rock to determine the percentage by mass of olivine using, for example, X-ray diffraction.
Olivine is mined in many locations around the world. In some embodiments the mined olivine may be subject to a preliminary processing step to reduce the size of the mined material. Accordingly, in some embodiments the olivine useful in the invention has an initial particle size of 20-50mm.
Any suitable apparatus can be used to reduce the initial particle size of the olivine to provide the mean particle sizes or cumulative specific surface area useful in the invention.
Examples of suitable apparatus include, but are not limited to, a plate mill, a ring mill, a horizontal rod mill, a jet mill, a ball mill and a vertical rolling mill. The person skilled in the art will appreciate how to operate these apparatus to obtain particles that are suitable for use in the invention.
Particle size can be determined by mass or by volume. The term "mean particle size" as used herein is calculated as Zxirrii, where m, is the fraction by mass at a given size Xi . In some embodiments a sample is subject to multiple analyses and the average result determined. Examples of suitable means for analysing particle size include, but are not limited to, laser particle size analysis, scanning electron microscope imaging and other optical techniques.
As used herein, the term "specific surface area" of particles means the area of the exterior surface of the particles. Specific surface area may be calculated by assuming that the particles are more or less spherical, and calculating the surface area based on particle size. Specific surface area may be calculated as surface area per mass, for example as surface area per kg of material. The term "cumulative surface area" as used herein takes into account the particle size distribution as well as individual surface area . Cumulative surface area can be calculated by adding together the specific surface area of the individual size fractions.
In some embodiments the olivine particles have a mean particle size of less than δθμηη. For example, the olivine particles may have a mean particle size of less than 75μηΊ, less than 70μη-ι, less than 65μηΊ, less than δθμηη, less than 55μηΊ, less than 50μηΊ, less than 45μηΊ, less than 40μη-ι, less than 35μηΊ, less than 30μηΊ, less than 25μηΊ, less than 20μηΊ, less than Ιδμηη, less than ΙΟμηη, less than 5μηΊ, or less than Ι μηη. Preferably the olivine particles have a mean particle size of less than 40μηι. Even more preferably, the olivine particles have a mean particle size of less than 20μηι.
In some embodiments at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη. For example, at least 15%, at least 20%, at least 25%, at least 30%, at least
35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% or at least 100% of the olivine particles have mean particle size of less than ΙΟμηη. Preferably at least 20% of the olivine particles have mean particle size of less than ΙΟμηη. Even more preferably, at least 30% of the olivine particles have mean particle size of less than ΙΟμηη. In some embodiments the olivine particles have a cumulative specific surface area of at least 18.2m2/kg. in some embodiments the olivine particles have a cumulative specific surface area of at least 150m2/kg, at least 250m2/kg, at least 500m2/kg, at least 750m2/kg, at least 1000m2/kg, at least 1250m2/kg, at least 1500m2/kg or at least 1800m2/kg.
Preferably the olivine particles have a cumulative specific surface area of at least 45m2/kg. Even more preferably, the olivine particles have a cumulative specific surface area of at least 90m2/kg.
Water is used to digest the olivine particles. In some embodiments the water has a pH of from 5 to 9. In some embodiments the water has a pH of from 6 to 8.5. In some embodiments the water has a pH of 7. Those persons skilled in the art can adjust the pH of the water using an appropriate acid or base. In some embodiments, the pH of the water is adjusted by dissolution of carbon dioxide.
In some embodiments the method comprises mixing the olivine particles with water. The temperature of the reaction mixture of olivine particles and water will typically be less than 200°C. For example, the temperature may be less than 180°C, less than 160°C, less than 140°C, less than 120°C, less than 100°C, less than 90°C, less than 60°C, less than 40°C or less than 20°C. In some embodiments the temperature may be 50°C. Generally, the olivine is mixed with cold water and the reaction mixture heated to the required
temperature. Alternatively, the olivine can be mixed with water that is already heated. In some embodiments the ratio of water to olivine particles is from 1000: 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is from 100 : 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is from 10 : 1 to 1 : 10. In some embodiments the ratio of water to olivine particles is 5 : 1, 2: 1, 1 : 2, or 1 : 5. In some embodiments the ratio of water to olivine particles is 1 : 1.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 150°C or less, wherein the olivine particles have a mean particle size of less than δθμηη, and wherein at least 30% of the olivine particles have a mean particle size of less than 10μη-ι.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 40μη-ι, and wherein at least 50% of the olivine particles have a mean particle size of less than 10μη-ι.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 40μη-ι, and wherein at least 30% of the olivine particles have a mean particle size of less than ΙΟμηη.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a mean particle size of less than 30μηΊ, and wherein at least 30% of the olivine particles have a mean particle size of less than ΙΟμηη.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 150°C or less, wherein the olivine particles have a cumulative specific surface area of at least 66 m2/kg.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 103m2/kg.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 78m2/kg.
In some particular embodiments the method comprises digesting olivine particles with water at a temperature of 90°C or less, wherein the olivine particles have a cumulative specific surface area of at least 87m2/kg.
In the particular embodiments above, the pH of the water is preferably from 6 to 8.5.
In the particular embodiments above, the ratio of water to olivine particles is preferably 2 : 1. In some embodiments the process is performed in one or more reaction vessels. For example, in some embodiments the reaction vessel is a stainless steel or fibreglass tank. In some embodiments the size of the reaction vessel may be 20 to 100m3.
In some embodiments the process is a batch process. However, the invention is not limited thereto and other embodiments, in which the process is a continuous process, are also contemplated.
The reaction mixture of olivine and water may be agitated. In some embodiments agitation is the result of stirring, a bubbling system, and/or the use of a pump or filter. In some embodiments air, carbon dioxide, or a mixture thereof are bubbled through the reaction mixture of olivine and water. In some embodiments currents can be created during the digestion process by feeding a slurry of olivine and water into the bottom and/or top of the reaction vessel.
In some embodiments olivine is digested with water until at least 20%, at least 50% or at least 80% of the olivine has reacted. One method for following progression of the digestion comprises monitoring the pH of the reaction mixture of olivine and water. In some embodiments olivine is digested with water until the pH of the reaction mixture has increased to 9.5 and then decreased by at least 0.5 pH. Another method for determining whether the digestion has sufficiently progressed comprises monitoring the rate at which hydrogen gas is produced. In some embodiments olivine is digested with water until the rate of hydrogen production increases less than 10%/day (or equivalent for different time steps). Another method for determining whether the digestion has sufficiently progressed comprises measuring the concentration of magnesium ions in the reaction mixture. In some embodiments the digestion continues for about one to about three days. Another method for determining whether the digestion has sufficiently progressed comprises monitoring the change in density as the reaction proceeds. Olivine has a density of approximately 3.3 g/cm3 and serpentine (i.e. the hydrolysis product of olivine) has a density of approximately 2.5-2.6 g/cm3. The person skilled in the art will appreciate that this method and/or others may be applied to both a batch process and a continuous process.
Digesting olivine with water produces Mg(OH)2 in solution in the reaction mixture. The Mg(OH)2 can be precipitated by any conventional means. For example, the Mg(OH)2 can be precipitated using an aqueous alkali solution with a pH greater than approximately 10.4. Suitable alkali solutions include but are not limited to aqueous solutions of alkali metal hydroxides, for example 0.1M solutions of NaOH or KOH. In some embodiments the supernatant containing Mg(OH)2 is continuously removed from the initial reaction vessel into a second reaction vessel and reacted with an aqueous alkali solution. The precipitated Mg(OH)2 may then be recovered from the second reaction vessel. In some embodiments olivine and/or serpentine particles are removed from the supernatant. Suitable means include, but are not limited to, a filter or a settling tank.
In some embodiments the recovered Mg(OH)2 is dehydrated to MgO. For example, in some embodiments the recovered Mg(OH)2 is heated, preferably to 300°C to 400°C. In some embodiments the recovered Mg(OH)2 may be subject to mechanical processing, such as centrifugation, before being heated. In some embodiments, after the precipitated Mg(OH)2 has been removed from the aqueous alkali solution, the aqueous alkali solution can be processed to obtain alkali hydroxides and water. In some embodiments, where a second reaction vessel is being used to precipitate the Mg(OH)2, the alkali hydroxides obtained from the aqueous alkali solution may be used to maintain the pH in the second reaction vessel. In some embodiments the water obtained from the aqueous alkali solution is used to digest further olivine with the method of the invention.
Alternatively, in some embodiments the Mg(OH)2 can be precipitated in the initial reaction vessel.
If the Mg(OH)2 precipitates in the initial reaction vessel, the Mg(OH)2 may not readily be separated from the residual solid. Accordingly, if separated Mg(OH)2 is required, the Mg(OH)2 concentration in the reaction mixture should be monitored so that the supernatant can be removed before precipitation occurs. In some embodiments the pH of the primary reaction vessel is maintained below approximately 10.5. For example, the pH can be kept below 10.5 by adding water to the reaction vessel.
The solid residue produced by the method may be separated from the liquid component of the reaction mixture by, for example, filtering the reaction mixture. In some embodiments, the solid residue is separated from the liquid component by vacuum filtration. Other methods of separating the solid residue of the reaction mixture from the liquid component may also be used, such as a phase separator, a hydrocyclone, extractor, or centrifuge. In some embodiments the solid residue may be separated from the liquid component by gravity settlement.
In some embodiments the hydrogen gas produced by the method is collected. In some embodiments the method of the invention is carried out in a sealed reaction vessel. In some embodiments the method of the invention is carried out under reduced pressure. Advantageously, these embodiments simplify recovery of the hydrogen gas. The person skilled in the art can readily envisage alternative methods of recovery. The collected hydrogen gas may be used as an energy source either in its own right, or to supplement the energy requirements of the process.
Serpentine and magnetite reaction products may also be recovered from the solid residue. In some embodiments the use of larger olivine particles in the method of the invention results in particles comprising a core of unreacted olivine surrounded by a layer of serpentine. In some embodiments these particles are recovered, reground and used as feedstock for the method of the invention.
In some embodiments, if the Mg(OH)2 precipitates in the initial reaction vessel, the serpentine or olivine/serpentine particles may also have a layer of Mg(OH)2. In some embodiments, if the Mg(OH)2 precipitates in the initial reaction vessel, the magnetite reaction products may have an outer layer of Mg(OH)2. In some embodiments these particles with a layer of Mg(OH)2 may be heated to dehydrate the Mg(OH)2, leaving a MgO layer on the surface of the particle.
In some embodiments the MgO obtained from the method of the invention can be combined with a finely divided amorphous silica to produce a construction material. In some embodiments the construction material is a magnesium silica binder. In some embodiments the ratio of silica to MgO is from 70: 30 to 30 : 70, preferably from 60:40 to 40 : 60. The silica
can be from a variety of sources including but not limited to fly ash, ground granulated blast furnace slag, naturally occurring amorphous silica (pumice for example) and silica fume. Preferably the silica has a particle size similar to or smaller than the MgO.
In some embodiments the MgO produced by the method of the invention can be used to prepare concrete. For example, in some embodiments concrete is prepared by mixing the MgO produced by the invention with aggregate, silica, sand and water. In some
embodiments the ratio of water to MgO is from 0.3 to 33 by mass. In some embodiments the ratio of water to MgO is from 1 to 3.3 by mass.
In some embodiments the magnesium silica binder of the invention can be used to prepare concrete. The person skilled in the art is familiar with methods for making concrete from binders, and the magnesium silica binder of the invention can be used in a manner comparable to traditional Portland cement. The person skilled in the art will be able to select the appropriate concrete preparation method depending on the particular application and the desired result. For example, in some embodiments concrete is prepared by mixing the magnesium silica binder of the invention with aggregate, sand and water. In some embodiments, the ratio of water to magnesium silica binder is 0.1 to 10. In some embodiments the ratio of water to magnesium silica binder is 0.3 to 1.
Alternatively, in some embodiments a concrete premix can be prepared by mixing the MgO produced by a method of the invention with aggregate, silica and sand.
In some embodiments the concrete premix may further comprise a set retarding additive. As used herein, the term "set retarding additive" refers to an additive that retards the setting of concrete. Examples of suitable set retarding additives include, but are not limited to, ammonium, alkali metals, alkaline earth metals, metal salts of sulfoalkylated lignins, organic acids (e.g., hydroxycarboxy acids), copolymers that comprise acrylic acid or maleic acid, and combinations thereof. In some embodiments the set retarding additive is included in the concrete premix in an amount sufficient to provide the desired set retardation. The person skilled in the art will be able to select the appropriate amount of the set retarding additive to include for a chosen application. For example, in some embodiments the set
retarding additive may be present in the concrete premix an amount in the range of 0.1% to 5% (by weight).
Optionally, other additional additives may be added to the concrete premix as considered appropriate by the person skilled in the art. Examples of such additives include, but are not limited to, viscosity modifiers, water reducing agents, air entraining agents, strength- retrogression additives, set accelerators, weighting agents, lightweight additives, gas- generating additives, mechanical property enhancing additives, lost-circulation materials, filtration-control additives, dispersants, fluid loss control additives, defoaming agents, foaming agents, oil-swellable particles, water-swellable particles, thixotropic additives, and combinations thereof. Specific examples of these, and other, additives include limestone, salts, fibers, hydratable clays, microspheres, rice husk ash, elastomers, elastomeric particles, resins, latex, combinations thereof, and the like. In some embodiments ground limestone is used to bulk up the concrete premix and control particle distribution. The person skilled in the art can determine the type and amount of additive useful for a particular application and desired result.
Figure 2 shows an embodiment of the overall reaction process. In particular, it shows the digestion of olivine with water in a primary reaction vessel to produce serpentine, Mg(OH)2, magnetite and hydrogen gas. In this embodiment, the supernatant is mixed with an alkali solution in a secondary reaction vessel to precipitate the Mg(OH)2. The precipitated
Mg(OH)2 is then heated to produce MgO and combined with silica for use in producing a magnesium based cement. Figure 2 also shows that serpentine may be recovered, and that some of the solid particles may have a layer of Mg(OH)2. The particles with a layer of Mg(OH)2 may be heated to produce a magnesium based cement.
Figure 2 further shows that the hydrogen gas produced by the digestion can be collected. The hydrogen gas may be used to provide heat for the dehydration of Mg(OH)2.
The following non-limiting examples are provided to illustrate the present invention and in no way limit the scope thereof.
EXAMPLES
Materials and methods
Olivine was sourced from Dunn Mountain, New Zealand. All other chemicals and reagents were standard laboratory supplies.
Sample preparation :
The weathering products were removed from the exterior of the olivine samples prior to grinding. The olivine samples were initially prepared in a jaw crusher resulting in material with a maximum particle size of less than 2 mm. Four samples were then ground using either a plate mill, 20 seconds in a ring mill, 1 minute in a ring mill or 8 hours in a horizontal rod mill with a load capacity of 6L.
Due to the limited capacity of the ring mill, approximately 50 grams, the olivine had to be processed in batches. The individual batches were blended to create a homogenous material for analysis. For each batch, the ring mill was charged with approximately 50g of olivine. Two sizes of 106 μηη and 42 μηη were obtained by operating the machine for 20 seconds and 1 minute respectively.
The plate mill was set with a distance between the plates equal to approximately 0.11mm. The olivine was added to the hopper at a rate of approximately 1 kg per minute. The average particle size was approximately 152 m.
The rod mill was charged with approximately 10 kg of olivine. The mill containing the steel rods rotated about the horizontal axis at a speed of approximately 30 revolutions per minute. The olivine was left in the rod mill for 8 hours resulting in an average fineness of approximately 41 m.
The average particle size for the different samples is set out in Table 2.
Table 2: Average particle size
Grinding Type Mean Size ( m) Median Size ( m)
Plate mill (01) 152.5 138.2
20 sec ring mill (02) 103.4 59.7
1 min ring mill (03) 44.0 19.1
8 hr rod mill (04) 41.8 19.6
Mean calculated = Zxirrii, where m, is the fraction by mass at a given size x
The particle size distribution, expressed as a percentage mass passing, is shown in Figure 1 and appears consistent with average particle sizes presented in Table 2.
Digestion of olivine to produce MqQ
Triplicate olivine samples were prepared for each level of grinding, temperature and duration. 3g of olivine and 6 ml of de-ionized water were added to 12 ml glass bottles and sealed with a septum lid to allow for extraction and analysis of the gas. The hydration of olivine was evaluated after 3 hours, 1 day, 3 days and 7 days at temperatures of 20°C and 50°C. The gas present in the head space above the olivine and water sample was drawn off with a syringe and analysed with a gas chromatograph to determine the hydrogen, oxygen, nitrogen and carbon dioxide concentrations. A summary of the specimen test conditions is provided in Table 3.
Table 3: Sample description
Approximately 4 ml of reaction mixture was filtered for ICPMS analysis.
Within 3 hours of mixing the ground olivine with water, the pH increased from
approximately 7 to at least 9.2, as shown in Figure 3. The rapid increase in pH indicates the formation of hydroxides as given in Equation 1 in Table 1. It is also evident from Figure 3 that the pH increased with the fineness of the olivine.
The pH increase did not continue over the period of the investigation but slowly decreased with further reaction times as shown in Figure 4. The system was closed to the atmosphere but some residual CO2 would have been present in the head space of each sample after
sealing. Without wishing to be bound by theory, it is thought that this residual CO2 from the air dissolved into the reaction mixture to reduce pH.
The magnesium and silica concentrations in the reaction mixture were at a maximum 3 hours after mixing and gradually decreased over the exposure period. The 20°C samples consistently had higher concentrations than 50°C samples for the comparable particle size. The change in magnesium concentration over the exposure period is provided in Figure 5 while the pronounced decrease in silica concentration for 20°C is show in Figure 6.
The relationship between dissolved silica and pH is provided in Figure 7.
The overall production of magnesium can be inferred from the accumulation of hydrogen in the head space of the container which is shown as an increase in H2 concentration in Figure 8.
The increase in temperature from 20°C to 50°C resulted in a noticeable increase in the measured hydrogen concentration and by extension the amount of MgO which would have been produced.
Analysis of Particle Size Distribution
A summary of the average particle size data for the four levels of grinding is shown above in Table 2. It can be seen from Table 2 that there is very little difference in either the mean or median particle size for the 1 minute ring mill or 8 hour rod mill while there is a clear difference between the plate mill, 20 second ring mill and the remaining two.
An examination of the hydrogen evolved from the different levels of grinding at 50°C, Figure 8b, shows a slightly different relationship. After 24 hours exposure the plate mill, 20 second ring mill, and 1 minute ring mill samples showed a similar level of reactivity as indicated by the hydrogen concentration despite very different particle size distributions. The results from the 8 hour rod mill samples are significantly different from the other samples with a hydrogen concentration approximately double that of the next highest.
Examination of the particle size distribution in Figure 9, expressed as specific surface area (m2/kg), revealed some noticeable difference between the various grinding levels.
While the average mean particle size is very similar between the 1 minute ring mill and 8 hour rod mill there is a greater quantity of very fine material for the 8 hr rod mill samples.
At 2.5 μΓη the cumulative surface area of the 8 hour rod mill samples is almost double that of the 1 minute ring mill. The difference in surface area decreases as the particle size diameter increases but even at 5 m the difference is approximately 50% and at 10 μηη 23%.
Without wishing to be bound by theory, it is thought this lower fine fraction is important for accelerating the rate of digestion.
Effect of digestion conditions
Three 4 gram samples of olivine were prepared as described above. Each sample had an average particle size of 41 μηη. Each sample was added to 80 ml of either soda water (CO2 injected) or deionized (DI) water. The soda water was a commercially available, off the shelf product, initially pressurized to approximately 2 bar. The pH of the soda water was approximately 5. Sample Paerated contained deionized water with air continuously bubbled through at a rate of approximately 1 l/min.
The reaction vessels were un-sealed and the concentration of dissolved CO2 would be expected to decrease with time for sample P5.
The reaction rates for olivine in all the solutions, based on changes in the measured pH, was fairly rapid, achieving quasi steady state pH values within approximately 1 to 10 minutes. After two hours at 20°C the solution was extracted, filtered at 0.45 μηη and stabilized with 0.03 ml of HNO3 (0. 1 M) and the magnesium concentration was measured.
Table 4: Reaction conditions and results
Solution Final pH Additional Mg Concentration
Sample starting
er 2 hrs conditions (mg/L)
condition aft
pH 5 soda
P5 6 162
water
P6 pH 6 DI water 10 21
2 hr
Paerated pH 6 DI water 8.7 48
aerated
Note: the pH values given are approximate values based on limited testing.
Table 4 shows the concentration of magnesium ions in solution increased for the reaction in soda water and, to a lesser extent, the aerated reaction, compared with the reaction in
deionized water. The highest level of dissolved magnesium was measured for the soda water solution.
References:
Hrsak, D. Malina, J. Hadzipasic, A. 2005, The Decomposition of Serpentine by Thermal Treatment, Materiali in Technologije, Vol. 39, pp. 225-227.
Wei, J. Chen, Y., Li, Y. 2006, The Reaction Mechanism between MgO and Microsilica at Room Temperature, Journal of Wuhan University of Technology, Mater. Sci. Ed., Vol. 21, No. 2, pp. 88-91.
Constantz, Laurence Clodic, Cecily Ryan, Miguel Fernandez, Kasra Farsad, Sidney Omelon, Phil Tuet, Paulo Monteiro, Jr. Gordon E. Brown, Katharine Geramita, 2010, Production of carbonate-containing compositions from material comprising metal silicates, WO
2010/006242.
Blencoe James G., Palmer Donald A., Anovitz Lawrence M., Beard James S., 2004,
Carbonation of metal silicates for long-term C02 sequestration, US 2004/0213705.
Nikolaos Vlasopoulos, Christopher Robert Cheeseman, 2009, Binder composition, WO 2009/156740.
Nikolaos Vlasopoulos, Christopher Robert Cheeseman, 2011, Binder composition, US
20110290155.
Nikolaos Vlasopoulos, 2011, Process for producing cement binder compositions containing magnesium, US 20130213273.
Amutha Rani Devaraj, Hai Xiang Lee, Diego Alfonso Martinez Velandia, Nikolaos
Vlasopoulos, 2014, Binder composition, US 20140290535. It is not the intention to limit the scope of the invention to the abovementioned examples only. As would be appreciated by a skilled person in the art, many variations are possible without departing from the scope of the invention.
Claims
1. A method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
2. A method according to claim 1, wherein the olivine particles have a mean particle size of less than 20μηι.
3. A method according to claim 1 or claim 2, wherein at least 30% of the olivine particles have a mean particle size of less than ΙΟμηη.
4. A method of producing Mg(OH)2 comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
5. A method according to claim 4, wherein the olivine particles have a cumulative specific surface area of at least 150m2/kg.
6. A method according to any one of claims 1 to 5, wherein the temperature is 90°C or less.
7. A method according to claim 6, wherein the temperature is 50°C or less.
8. A method according to any one of claims 1 to 7, wherein the water has a pH from 5 to 7.
9. A method according to any one of claims 1 to 8, wherein the water has a pH of 5.
10. A method according to any one of claims 1 to 8, wherein the water has a pH of 6.
11. A method according to any one of claims 1 to 8, wherein the water has a pH of 7.
12. A method according to any one of claims 1 to 7, wherein the water has a pH from 5 to 9.
13. A method according to any one of claims 1 to 7 and 12, wherein the water has a pH from 6 to 8.
14. A method according to any one of claims 1 to 10, wherein the water comprises dissolved carbon dioxide.
15. A method according to any one of claims 1 to 14, wherein the digesting further comprises agitating the olivine particles and water.
16. A method according to claim 15, wherein the agitating is by bubbling.
17. A method according to claim 16, wherein the agitating is by bubbling air, carbon dioxide or a mixture thereof.
18. A method according to any one of claims 1 to 17, wherein the method further produces hydrogen gas.
19. A method according to any one of claims 1 to 18, wherein the method further produces magnetite.
20. A method according to any one of claims 1 to 19, wherein the method further produces silica dioxide.
21. A method according to any one of claims 1 to 20, wherein the method further comprises precipitating the Mg(OH)2.
22. A method according to claim 21, wherein the Mg(OH)2 is precipitated using an alkali solution.
23. A method according to claim 21 or claim 22, wherein the method further comprises recovering the precipitated Mg(OH)2.
24. A method according to claim 23, wherein the method further comprises dehydrating the precipitated Mg(OH)2 to produce MgO.
25. A method according to claim 24, wherein the method further comprises combining the MgO with silica to produce a magnesium silica binder.
26. A method according to claim 25, further comprising using the magnesium silica binder to produce concrete.
27. A method according to any one of claims 1 to 20, wherein Mg(OH)2 forms a layer on the olivine particles.
28. A method according to claim 24, wherein the olivine particles further comprise a layer of serpentine beneath the Mg(OH)2 layer.
29. Mg(OH)2 produced by the method according to any one of claims 1 to 23, 27 or 28.
30. A magnesium silica binder produced by the method of claim 25.
31. Use of Mg(OH)2 according to claim 29 to produce concrete.
32. Use of a magnesium silica binder according to claim 30 to produce concrete.
33. A method of making concrete, comprising mixing the magnesium silica binder of claim 30 with aggregate and water.
34. Concrete, when made by a method of claim 26 or claim 33.
35. A concrete premix comprising the binder of claim 30 and aggregate.
36. A method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
37. A method of producing hydrogen gas comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
38. A method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
39. A method of producing magnetite comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
40. A method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of less than ΙΟΟμηη, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
41. A method of producing silica dioxide comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
42. A method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a mean particle size of
less than ΙΟΟμηι, and wherein at least 10% of the olivine particles have a mean particle size of less than ΙΟμηη.
43. A method of producing serpentine comprising digesting olivine particles with water at a temperature of 200°C or less, wherein the olivine particles have a cumulative specific surface area of at least 18.2 m2/kg.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NZ721531 | 2016-06-24 | ||
NZ72153116 | 2016-06-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2017222396A1 true WO2017222396A1 (en) | 2017-12-28 |
Family
ID=60783933
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/NZ2017/050086 WO2017222396A1 (en) | 2016-06-24 | 2017-06-23 | Magnesium containing compositions |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2017222396A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2023110102A1 (en) * | 2021-12-16 | 2023-06-22 | Ocs 2 Ug (Haftungsbeschränkt) | Reinforced magnesium silicate hydrate composite material |
WO2023118396A1 (en) * | 2021-12-23 | 2023-06-29 | Frank Bellmann | Use of alkali-sensitive aggregate for concrete production, concrete mixture, concrete and process for production thereof |
US11890572B1 (en) | 2022-09-15 | 2024-02-06 | Aspiring Materials Limited | Soda magcite composition, methods of manufacture and use in carbon dioxide (CO2) sequestration |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4983342A (en) * | 1986-01-10 | 1991-01-08 | Norsk Proco A/S | Method of making water and fire resistant building material |
US20090301352A1 (en) * | 2007-12-28 | 2009-12-10 | Constantz Brent R | Production of carbonate-containing compositions from material comprising metal silicates |
WO2010100329A1 (en) * | 2009-03-06 | 2010-09-10 | Oy Keskuslaboratorio - Centrallaboratorium Ab | Silicon compound, method for forming same, and use of same |
ES2451567B1 (en) * | 2012-09-26 | 2015-01-23 | Pasek Minerales, S.A.U. | Procedure for obtaining high purity magnesium oxide and hydroxide from dunites |
-
2017
- 2017-06-23 WO PCT/NZ2017/050086 patent/WO2017222396A1/en active Application Filing
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4983342A (en) * | 1986-01-10 | 1991-01-08 | Norsk Proco A/S | Method of making water and fire resistant building material |
US20090301352A1 (en) * | 2007-12-28 | 2009-12-10 | Constantz Brent R | Production of carbonate-containing compositions from material comprising metal silicates |
WO2010100329A1 (en) * | 2009-03-06 | 2010-09-10 | Oy Keskuslaboratorio - Centrallaboratorium Ab | Silicon compound, method for forming same, and use of same |
ES2451567B1 (en) * | 2012-09-26 | 2015-01-23 | Pasek Minerales, S.A.U. | Procedure for obtaining high purity magnesium oxide and hydroxide from dunites |
Non-Patent Citations (3)
Title |
---|
MOTTL, M. J.: "Serpentinization, Abiogenic Methane", EXTREMOPHILIC ARCHAEA WITHIN THE SEAFLOOR, January 2005 (2005-01-01), Retrieved from the Internet <URL:www.ifa.hawaii.edu/UHNAI/NAlweb/presentations/Mariana%20Foreare.pdf> * |
NEUBECK, A. ET AL.: "Olivine Alteration and H2 production in carbonate-rich, low temperature aqueous environments", PLANETARY AND SPACE SCIENCE, vol. 96, 2014, pages 51 - 61, XP029026414 * |
SLEEP, N. H. ET AL.: "H2-rich fluids from serpentinization: Geochemical and biotic implications", PNAS, vol. 101, no. 35, 2004, pages 12818 - 12823, XP055448666 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2023110102A1 (en) * | 2021-12-16 | 2023-06-22 | Ocs 2 Ug (Haftungsbeschränkt) | Reinforced magnesium silicate hydrate composite material |
WO2023118396A1 (en) * | 2021-12-23 | 2023-06-29 | Frank Bellmann | Use of alkali-sensitive aggregate for concrete production, concrete mixture, concrete and process for production thereof |
US11890572B1 (en) | 2022-09-15 | 2024-02-06 | Aspiring Materials Limited | Soda magcite composition, methods of manufacture and use in carbon dioxide (CO2) sequestration |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Tan et al. | Preparation for micro-lithium slag via wet grinding and its application as accelerator in Portland cement | |
Liu et al. | Effects of temperature and carbonation curing on the mechanical properties of steel slag-cement binding materials | |
Samarakoon et al. | Effect of soda-lime glass powder on alkali-activated binders: Rheology, strength and microstructure characterization | |
TWI478891B (en) | Expandable material and its manufacturing method | |
Wang et al. | Synergistic effects of supplementary cementitious materials in limestone and calcined clay-replaced slag cement | |
EP3452423A1 (en) | Synthetic pozzolans | |
CN109516484B (en) | Method for producing alumina by sintering carbide slurry fly ash and coal gangue | |
CN112794666B (en) | Iron tailing non-sintered ceramsite and preparation method thereof | |
Sadique et al. | A new composite cementitious material for construction | |
CN112723843B (en) | Preparation method of weak-base-excited nickel slag high-strength concrete | |
Wang et al. | Extraction of alumina from fly ash by ammonium hydrogen sulfate roasting technology | |
Wang et al. | Extraction of aluminum hydroxide from coal fly ash by pre-desilication and calcination methods | |
WO2017222396A1 (en) | Magnesium containing compositions | |
CN111302678A (en) | In-situ oxidation modified steel slag and preparation method and application thereof | |
Mejdoub et al. | The effect of prolonged mechanical activation duration on the reactivity of Portland cement: Effect of particle size and crystallinity changes | |
WO2013059799A1 (en) | Method and compositions for pozzolanic binders derived from non-ferrous smelter slags | |
US7537653B2 (en) | Microsilica materials with improved pozzolanic activity | |
Li et al. | Mechanical properties and hydration mechanism of high-volume ultra-fine iron ore tailings cementitious materials | |
CN114044636A (en) | Metal mine underground filling cementing material, and preparation method and application thereof | |
Zhang et al. | Effects of sodium doping on carbonation behavior of α-CS | |
Alelweet et al. | Pozzolanic and cementing activity of raw and pyro-processed Saudi Arabian red mud (RM) waste | |
Lu et al. | High-purity vaterite CaCO3 recovery through wet carbonation of magnesium slag and leaching residue utilization in cement | |
CN114394770A (en) | Preparation method of tungsten tailing cement admixture | |
Liu et al. | Resource utilization of solid waste from steel industries in cement-based cementitious materials: mechanical properties, hydration behaviors, and environmental impact | |
Sun et al. | Preparation and characteristics of modified red mud-municipal solid waste incineration bottom ash binder |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 17815781 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 17815781 Country of ref document: EP Kind code of ref document: A1 |