JP7382463B1 - alkaline agent - Google Patents
alkaline agent Download PDFInfo
- Publication number
- JP7382463B1 JP7382463B1 JP2022119560A JP2022119560A JP7382463B1 JP 7382463 B1 JP7382463 B1 JP 7382463B1 JP 2022119560 A JP2022119560 A JP 2022119560A JP 2022119560 A JP2022119560 A JP 2022119560A JP 7382463 B1 JP7382463 B1 JP 7382463B1
- Authority
- JP
- Japan
- Prior art keywords
- mgo
- content
- alkaline agent
- crystallite diameter
- mass
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 185
- 239000002245 particle Substances 0.000 claims abstract description 62
- 238000010828 elution Methods 0.000 claims abstract description 21
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 19
- 238000005259 measurement Methods 0.000 claims abstract description 11
- 239000011777 magnesium Substances 0.000 claims abstract description 8
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 7
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 7
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 6
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052742 iron Inorganic materials 0.000 claims abstract description 6
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 6
- 239000000395 magnesium oxide Substances 0.000 claims description 101
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 34
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 13
- 238000012360 testing method Methods 0.000 claims description 13
- 239000000725 suspension Substances 0.000 claims description 9
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 7
- 230000001186 cumulative effect Effects 0.000 claims description 7
- 238000004448 titration Methods 0.000 claims description 4
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 5
- 239000000377 silicon dioxide Substances 0.000 abstract description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 abstract 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 238000010586 diagram Methods 0.000 abstract 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract 1
- 235000012239 silicon dioxide Nutrition 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 238000010304 firing Methods 0.000 description 13
- 238000010298 pulverizing process Methods 0.000 description 12
- 150000002681 magnesium compounds Chemical class 0.000 description 10
- 239000000463 material Substances 0.000 description 9
- 239000012535 impurity Substances 0.000 description 8
- 239000013078 crystal Substances 0.000 description 7
- 238000004090 dissolution Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000002441 X-ray diffraction Methods 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 6
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 5
- 239000000347 magnesium hydroxide Substances 0.000 description 5
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 5
- 239000000654 additive Substances 0.000 description 4
- 239000011575 calcium Substances 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000003513 alkali Substances 0.000 description 3
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 3
- 239000000920 calcium hydroxide Substances 0.000 description 3
- 235000011116 calcium hydroxide Nutrition 0.000 description 3
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 3
- 239000000292 calcium oxide Substances 0.000 description 3
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 3
- 239000001095 magnesium carbonate Substances 0.000 description 3
- 235000014380 magnesium carbonate Nutrition 0.000 description 3
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000002689 soil Substances 0.000 description 3
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 2
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000011324 bead Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- YIXJRHPUWRPCBB-UHFFFAOYSA-N magnesium nitrate Chemical compound [Mg+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O YIXJRHPUWRPCBB-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000002407 reforming Methods 0.000 description 2
- 239000013535 sea water Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 238000011088 calibration curve Methods 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- PSHMSSXLYVAENJ-UHFFFAOYSA-N dilithium;[oxido(oxoboranyloxy)boranyl]oxy-oxoboranyloxyborinate Chemical compound [Li+].[Li+].O=BOB([O-])OB([O-])OB=O PSHMSSXLYVAENJ-UHFFFAOYSA-N 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- YWXYYJSYQOXTPL-SLPGGIOYSA-N isosorbide mononitrate Chemical compound [O-][N+](=O)O[C@@H]1CO[C@@H]2[C@@H](O)CO[C@@H]21 YWXYYJSYQOXTPL-SLPGGIOYSA-N 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 229910001629 magnesium chloride Inorganic materials 0.000 description 1
- 159000000003 magnesium salts Chemical class 0.000 description 1
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 1
- 235000019341 magnesium sulphate Nutrition 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003002 pH adjusting agent Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 229910021487 silica fume Inorganic materials 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000010421 standard material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 238000005303 weighing 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
- C01F5/02—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
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K17/00—Soil-conditioning materials or soil-stabilising materials
- C09K17/02—Soil-conditioning materials or soil-stabilising materials containing inorganic compounds only
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Soil Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
【課題】適度な溶出速度を有し、長期にわたって安定した効果を発揮可能なアルカリ剤を提供する。【解決手段】本発明に係るアルカリ剤は、結晶子径が８０～３００ｎｍ、ＢＥＴ比表面積が０．１～１．２ｍ２／ｇであって、ＭｇＯ含有率が９５．０質量％以上である酸化マグネシウム粒子を含有することを特徴とする。（ＭｇＯ含有率は、蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に変換した際の含有率（質量％）合計を１００としたときの値である。）【選択図】なしAn object of the present invention is to provide an alkaline agent that has an appropriate elution rate and can exhibit stable effects over a long period of time. [Solution] The alkaline agent according to the present invention has a crystallite diameter of 80 to 300 nm, a BET specific surface area of 0.1 to 1.2 m2/g, and an MgO content of 95.0% by mass or more. It is characterized by containing magnesium particles. (MgO content is the content (mass%) when the five elements Mg, Ca, Si, Fe, and Al detected by fluorescent X-ray measurement are converted into MgO, CaO, SiO2, Fe2O3, and Al2O3, respectively. This is the value when the total is 100.) [Selection diagram] None
Description
本発明は、アルカリ剤に関する。 The present invention relates to an alkaline agent.
水質や土壌等の環境を、アルカリ性に改質・維持する材料（アルカリ剤）が必要とされる場面がある。このようなアルカリ剤は、肥料、塗料等においても用いられる。例えば、特許文献１には、酸化マグネシウムまたは酸化カルシウムによる土壌改質効果を、母材やｐＨ調整剤との併用により抑制した土壌改質材が記載されている。また、特許文献２には、特定組成を有する鋼材の表面に、アルカリ金属濃縮領域を有する非水溶性塗膜を形成した塗装鋼材が記載されている。 There are situations in which materials (alkaline agents) are required to modify and maintain environments such as water and soil to be alkaline. Such alkaline agents are also used in fertilizers, paints, etc. For example, Patent Document 1 describes a soil reforming material in which the soil reforming effect of magnesium oxide or calcium oxide is suppressed by using the material in combination with a base material or a pH adjuster. Further, Patent Document 2 describes a coated steel material in which a water-insoluble coating film having an alkali metal enriched region is formed on the surface of a steel material having a specific composition.
環境改質という目的から、改質効果の発生源となるアルカリ剤は適度な溶出速度を有し、長期にわたって効果を維持することが期待される。しかしながら、アルカリ剤自体の溶出速度についてはこれまで特に着目されておらず、十分な検討が行われていない。 For the purpose of environmental modification, the alkaline agent that is the source of the modification effect is expected to have an appropriate elution rate and maintain its effect over a long period of time. However, no particular attention has been paid to the elution rate of the alkaline agent itself, and sufficient studies have not been conducted.
そこで本発明は、適度な溶出速度を有し、長期にわたって安定した効果を発揮可能なアルカリ剤を提供することを目的とする。 Therefore, an object of the present invention is to provide an alkaline agent that has an appropriate elution rate and can exhibit stable effects over a long period of time.
本発明に係るアルカリ剤は、結晶子径が８０～３００ｎｍ、ＢＥＴ比表面積が０．１～１．２ｍ２／ｇであって、ＭｇＯ含有率が９５．０質量％以上である酸化マグネシウム粒子を含有することを特徴とする。 The alkaline agent according to the present invention contains magnesium oxide particles having a crystallite diameter of 80 to 300 nm, a BET specific surface area of 0.1 to 1.2 m 2 /g, and an MgO content of 95.0% by mass or more. It is characterized by containing.
本発明によれば、適度な溶出速度を有し、長期にわたって安定した効果を発揮可能なアルカリ剤を提供することができる。 According to the present invention, it is possible to provide an alkaline agent that has an appropriate elution rate and can exhibit stable effects over a long period of time.
本発明者ら鋭意検討の結果、結晶子径およびＢＥＴ比表面積が所定範囲内であって、所定量の酸化マグネシウムを含有する酸化マグネシウム粒子が、適度な溶出速度を有することを見出し、本発明を完成させるに至った。
以下、本発明の実施形態を詳細に説明する。
As a result of extensive studies, the present inventors found that magnesium oxide particles having a crystallite diameter and a BET specific surface area within a predetermined range and containing a predetermined amount of magnesium oxide have an appropriate dissolution rate, and have developed the present invention. I ended up completing it.
Embodiments of the present invention will be described in detail below.
本発明のアルカリ剤には、結晶子径およびＢＥＴ比表面積が所定範囲内に規定された酸化マグネシウム粒子（ＭｇＯ粒子）が含有される。ＭｇＯ粒子においては、９５質量％以上を酸化マグネシウムが占め、不純物が存在することもできる。 The alkaline agent of the present invention contains magnesium oxide particles (MgO particles) whose crystallite diameter and BET specific surface area are defined within a predetermined range. In the MgO particles, magnesium oxide accounts for 95% by mass or more, and impurities may also be present.
本発明におけるＭｇＯ粒子の結晶子径は８０～３００ｎｍである。結晶子径が８０～３００ｎｍの範囲内であることによって、適度な溶出性を確保することができる。ＭｇＯ粒子は、結晶子径が小さいほど、溶出が速くなる傾向にある。ＭｇＯ粒子の結晶子径は、好ましくは８５～２７５ｎｍであり、より好ましくは９０～２５０ｎｍである。結晶子径は、ＸＲＤパターンにおけるＭｇＯ（００２）面ピークを解析ソフトで処理することにより得られた値である。一般に、一つの粒子は複数の単結晶で構成された多結晶体であり、結晶子径は多結晶体中の単結晶の大きさの平均値を示している。 The crystallite diameter of the MgO particles in the present invention is 80 to 300 nm. By having a crystallite diameter within the range of 80 to 300 nm, appropriate dissolution properties can be ensured. MgO particles tend to elute faster as the crystallite size becomes smaller. The crystallite diameter of the MgO particles is preferably 85 to 275 nm, more preferably 90 to 250 nm. The crystallite diameter is a value obtained by processing the MgO (002) plane peak in the XRD pattern using analysis software. Generally, one particle is a polycrystalline body composed of a plurality of single crystals, and the crystallite diameter indicates the average size of the single crystals in the polycrystalline body.
後述するように、本発明におけるＭｇＯ粒子は、マグネシウム化合物を焼成してなるマグネシア焼結体から得られ、その際の焼成温度によって結晶子径を制御することができる。マグネシアは、原料となるマグネシウム化合物の熱分解により生じる場合が多く、微細な結晶が発生した後に焼成温度に応じて結晶成長が進行する。ＭｇＯ粒子の結晶子径は、不純物含有量による調整も可能である。Ｓｉ等は、結晶成長を促進する傾向があり、特に、ＭｇＯ含有率９９質量％以下のマグネシア焼結体では結晶成長が促進されやすい。さらに、マグネシア焼結体を粉砕してＭｇＯ粒子の結晶子径を減少させることも可能である。 As described later, the MgO particles in the present invention are obtained from a magnesia sintered body formed by firing a magnesium compound, and the crystallite diameter can be controlled by the firing temperature at that time. Magnesia is often produced by thermal decomposition of a magnesium compound as a raw material, and after fine crystals are generated, crystal growth progresses depending on the firing temperature. The crystallite diameter of MgO particles can also be adjusted by adjusting the impurity content. Si and the like tend to promote crystal growth, and crystal growth is particularly likely to be promoted in a magnesia sintered body with an MgO content of 99% by mass or less. Furthermore, it is also possible to reduce the crystallite size of the MgO particles by pulverizing the magnesia sintered body.
また、ＭｇＯ粒子は、ＢＥＴ比表面積が０．１～１．２ｍ２／ｇに規定される。これによって、適度な溶出性を確保することができる。ＭｇＯ粒子のＢＥＴ比表面積は、好ましくは１．０ｍ２／ｇ以下、より好ましくは０．８ｍ２／ｇ以下、さらに好ましくは０．６ｍ２／ｇ以下である。また、ＭｇＯ粒子のＢＥＴ比表面積は、０．１５ｍ２／ｇ以上が好ましく、０．２５ｍ２／ｇ以上がより好ましい。 Furthermore, the BET specific surface area of the MgO particles is defined as 0.1 to 1.2 m 2 /g. Thereby, appropriate dissolution properties can be ensured. The BET specific surface area of the MgO particles is preferably 1.0 m 2 /g or less, more preferably 0.8 m 2 /g or less, even more preferably 0.6 m 2 /g or less. Further, the BET specific surface area of the MgO particles is preferably 0.15 m 2 /g or more, more preferably 0.25 m 2 /g or more.
ＭｇＯ粒子のＢＥＴ比表面積は、マグネシア焼結体の焼成温度により制御することができる。焼成温度が高いほど、ＢＥＴ比表面積は小さくなる傾向にある。また、焼成されたマグネシア焼結体を粉砕することで、ＢＥＴ比表面積を増大させることも可能である。加えて、焼成および／または粉砕されたマグネシア焼結体を分級することによって、任意のＢＥＴ比表面積を有する粒子を主体とする粒子を選別することもできる。 The BET specific surface area of the MgO particles can be controlled by the firing temperature of the magnesia sintered body. The higher the firing temperature, the smaller the BET specific surface area tends to be. Moreover, it is also possible to increase the BET specific surface area by crushing the fired magnesia sintered body. In addition, by classifying the fired and/or pulverized magnesia sintered body, it is also possible to select particles mainly consisting of particles having an arbitrary BET specific surface area.
本発明におけるＭｇＯ粒子は、結晶子径およびＢＥＴ比表面積が所定範囲内であることに加えて、ＭｇＯ含有率が９５質量％以上であるので、適度な速度でアルカリを溶出し、長期にわたって安定した効果を発揮することができる。ＭｇＯ含有率は、ＭｇＯ粒子中の９９．０質量％以下であることが好ましく、９５．５～９８．５質量％であることがより好ましく、９６．０～９８．０質量％であることがさらにより好ましい。
ＭｇＯ粒子中のＭｇＯ含有率は、蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に換算した際の含有率（質量％）合計を１００としたときのＭｇＯの含有率である
The MgO particles in the present invention have a crystallite diameter and a BET specific surface area within a predetermined range, and also have an MgO content of 95% by mass or more, so they elute alkali at an appropriate rate and are stable over a long period of time. It can be effective. The MgO content in the MgO particles is preferably 99.0% by mass or less, more preferably 95.5 to 98.5% by mass, and preferably 96.0 to 98.0% by mass. Even more preferred.
The MgO content in MgO particles is determined by converting the five elements Mg, Ca, Si, Fe, and Al detected by fluorescent X-ray measurement into MgO, CaO, SiO 2 , Fe 2 O 3 , and Al 2 O 3 respectively. It is the MgO content when the converted content (mass%) total is 100.
アルカリ溶出速度の測定には、５０ｍｇのＭｇＯ粒子を１００ｍＬのイオン交換水に分散させたＭｇＯ懸濁液と、０．０５ｍｏｌ／Ｌの硫酸とを用いる。電位差自動滴定装置を用い、硫酸を滴下することでＭｇＯ懸濁液のｐＨを３に維持し、ｐＨ維持に要した硫酸消費量を求める。具体的には、下記式（２）で表される溶出速度試験値Ｘで評価することができる。
Ｘ＝ｍ／ｔ （２）
（上記式（２）中、ｍは、ＭｇＯ懸濁液のｐＨを３に維持する溶出試験の（終点における硫酸ｍｏｌ／ＭｇＯｍｏｌ）であり、ｔは、滴定時間（ｓ）である。）
こうして得られる溶出速度試験値Ｘが０．０００３５以下であれば、適度な溶出速度を有し、長期間作用を発揮することができる。溶出速度試験値Ｘは、０．０００２５以下がより好ましく、０．０００２０以下がさらに好ましい。溶出速度試験値Ｘの下限は特に限定されないが、０．００００３以上が好ましく、０．００００５以上がより好ましく、０．０００１０以上がさらに好ましい。
To measure the alkali elution rate, an MgO suspension in which 50 mg of MgO particles are dispersed in 100 mL of ion-exchanged water and 0.05 mol/L sulfuric acid are used. Using an automatic potentiometric titrator, the pH of the MgO suspension is maintained at 3 by dropping sulfuric acid, and the amount of sulfuric acid consumed to maintain the pH is determined. Specifically, it can be evaluated using the dissolution rate test value X expressed by the following formula (2).
X=m/t (2)
(In the above formula (2), m is (sulfuric acid mol/MgOmol at the end point) of the elution test in which the pH of the MgO suspension is maintained at 3, and t is the titration time (s).)
If the dissolution rate test value X obtained in this manner is 0.00035 or less, it has an appropriate dissolution rate and can exhibit long-term action. The elution rate test value X is more preferably 0.00025 or less, and even more preferably 0.00020 or less. The lower limit of the elution rate test value X is not particularly limited, but is preferably 0.00003 or more, more preferably 0.00005 or more, and even more preferably 0.00010 or more.
ＭｇＯ粒子は不純物として、例えばＣａ，Ｓｉ，Ｆｅ，Ａｌ等を含有することができる。不純物に関しては、下記式（１）で表されるＳ／Ｍ比で評価することができる。
Ｓ／Ｍ＝ＸＲＦ（Ｓ）／ＸＲＦ（Ｍ） （１）
ＸＲＦ（Ｓ）およびＸＲＦ（Ｍ）は、それぞれ、蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に換算した際の含有率（質量％）合計を１００としたときのＳｉＯ２含有率（Ｓ）およびＭｇＯ含有率（Ｍ）である。
MgO particles can contain impurities such as Ca, Si, Fe, Al, etc. Regarding impurities, it can be evaluated by the S/M ratio expressed by the following formula (1).
S/M=XRF(S)/XRF(M) (1)
XRF (S) and XRF (M) respectively convert the five elements Mg, Ca, Si, Fe, and Al detected by fluorescent X-ray measurement into MgO, CaO, SiO 2 , Fe 2 O 3 , and Al. These are the SiO 2 content (S) and the MgO content (M) when the total content (mass %) converted to 2 O 3 is 100.
（Ｓ／Ｍ比）が、０．００４～０．０４０の場合には、安定性が向上し、粉砕分級の際に表面に多くの負荷を受けた場合でも、耐湿性を維持する傾向にある。マグネシア焼結体の焼成時に形成される異相（Ｓｉ－Ｍｇ化合物）が、吸湿等による変質の内部浸透を遅らせるものと推測される。（Ｓ／Ｍ比）は、０．００６～０．０３５が好ましく、０．００７～０．０２０がより好ましい。 When the (S/M ratio) is between 0.004 and 0.040, stability improves and moisture resistance tends to be maintained even when the surface is subjected to a large load during pulverization and classification. . It is presumed that the different phase (Si--Mg compound) formed during firing of the magnesia sintered body delays internal penetration of deterioration due to moisture absorption and the like. (S/M ratio) is preferably 0.006 to 0.035, more preferably 0.007 to 0.020.
ＭｇＯ粒子の５０％体積累積粒径（Ｄ５０）は、１～２００μｍであることが好ましい。Ｄ５０がこの範囲内であることによって、適度な溶出速度を発揮することができる。焼成温度が高いほど、Ｄ５０は増大する傾向にある。また、焼成されたマグネシア焼結体を粉砕することで、Ｄ５０を減少させることも可能である。加えて、焼成および／または粉砕されたマグネシア焼結体を分級することによって、Ｄ５０を任意の範囲に調整することもできる。ＭｇＯ粒子のＤ５０は、１０～１５０μｍであることがより好ましく、２０～１００μｍであることがさらに好ましい。 The 50% volume cumulative particle diameter (D50) of the MgO particles is preferably 1 to 200 μm. When D50 is within this range, an appropriate elution rate can be achieved. D50 tends to increase as the firing temperature increases. Furthermore, it is also possible to reduce D50 by pulverizing the fired magnesia sintered body. In addition, D50 can also be adjusted to an arbitrary range by classifying the fired and/or crushed magnesia sintered body. The D50 of the MgO particles is more preferably 10 to 150 μm, and even more preferably 20 to 100 μm.
ＭｇＯ粒子は、５０％体積累積粒径（Ｄ５０）と結晶子径との比（Ｄ５０／結晶子径）が、１００～６００の範囲内であることが好ましい。（Ｄ５０／結晶子径）が小さいほど、結晶構造の破断面を粒子表面に露出する可能性が高まり、耐湿性等の安定性が低下すると考えられる。１００～６００の範囲内であれば、耐湿性を向上させることができる。（Ｄ５０／結晶子径）は、１５０～５５０が好ましく、２００～５００がより好ましい。 The ratio of the 50% volume cumulative particle diameter (D50) to the crystallite diameter (D50/crystallite diameter) of the MgO particles is preferably within the range of 100 to 600. It is thought that the smaller the (D50/crystallite diameter), the higher the possibility that the fractured surface of the crystal structure will be exposed on the particle surface, and the stability such as moisture resistance will decrease. If it is within the range of 100 to 600, moisture resistance can be improved. (D50/crystallite diameter) is preferably 150 to 550, more preferably 200 to 500.
ＭｇＯ粒子の耐湿性は、加湿試験における質量増加率から評価することができる。温度５０℃湿度８５％の雰囲気中に１２０時間保持した際、質量増加率が２％以下であることが好ましい。質量増加率は、１．５％以下であることがより好ましく、１．０％以下であることがさらに好ましい。 The moisture resistance of MgO particles can be evaluated from the mass increase rate in a humidification test. It is preferable that the mass increase rate is 2% or less when kept in an atmosphere at a temperature of 50° C. and a humidity of 85% for 120 hours. The mass increase rate is more preferably 1.5% or less, and even more preferably 1.0% or less.
本発明のアルカリ剤は、マグネシア焼結体を粉砕し、必要に応じて分級することで得ることができる。
マグネシア焼結体は、例えば、水酸化マグネシウム、炭酸マグネシウム、塩化マグネシウム、硝酸マグネシウム、硫酸マグネシウム等のマグネシウム化合物を焼成して得ることができる。水酸化マグネシウムとしては、海水中のマグネシウム塩と水酸化カルシウムとの反応で沈殿したものなどを使用することができる。炭酸マグネシウムとしては、マグネサイト鉱石などを使用することができる。
The alkaline agent of the present invention can be obtained by pulverizing a magnesia sintered body and, if necessary, classifying it.
The magnesia sintered body can be obtained, for example, by firing a magnesium compound such as magnesium hydroxide, magnesium carbonate, magnesium chloride, magnesium nitrate, or magnesium sulfate. As magnesium hydroxide, one precipitated by a reaction between magnesium salt and calcium hydroxide in seawater can be used. As magnesium carbonate, magnesite ore or the like can be used.
マグネシウム化合物の焼成は、大気中、１３００～２８００℃で行うことが好ましい。１３００℃未満の場合には、結晶子径は所定範囲より小さく、ＢＥＴ比表面積は所定範囲より大きくなる傾向にあり、過度な溶出速度を有する材料となりやすい。一方、２８００℃を超えると、結晶子径が所定範囲より大きく、ＢＥＴ比表面積が所定範囲より小さくなる傾向にあり、アルカリ剤としての機能が不十分な材料となりやすい。焼成温度は、１４００～２４００℃がより好ましい。焼成時間は、１０分間～１０時間とすることが好ましい。 Calcination of the magnesium compound is preferably carried out at 1300 to 2800°C in the air. When the temperature is less than 1300°C, the crystallite diameter tends to be smaller than the predetermined range, the BET specific surface area tends to be larger than the predetermined range, and the material tends to have an excessive elution rate. On the other hand, if the temperature exceeds 2800° C., the crystallite diameter tends to be larger than the predetermined range, the BET specific surface area tends to be smaller than the predetermined range, and the material tends to have insufficient function as an alkaline agent. The firing temperature is more preferably 1400 to 2400°C. The firing time is preferably 10 minutes to 10 hours.
ＭｇＯ含有率を含むＭｇＯ粒子中の成分含有量は、マグネシア焼結体を焼成する際に調整することができる。具体的には、焼成原料となるマグネシウム化合物の選択、および、Ｓｉ等の不純物に対応する添加物の使用により制御することができる。製造効率を考慮すると、原料となるマグネシウム化合物中の不純物量を参照し、マグネシウム化合物の選択と組み合わせにより調整することが好ましい。 The component content in the MgO particles, including the MgO content, can be adjusted when firing the magnesia sintered body. Specifically, it can be controlled by selecting the magnesium compound used as the firing raw material and by using additives corresponding to impurities such as Si. Considering production efficiency, it is preferable to adjust by selecting and combining magnesium compounds with reference to the amount of impurities in the magnesium compound as a raw material.
Ｓｉ含有量は、任意の添加剤により調整することができる。添加剤は特に限定されないが、例えば、シリカフューム、珪砂、ケイ酸ナトリウム等が挙げられる。マグネシウム化合物としては、流通品を用いることも可能だが、公知の手段を用いて成分調整したマグネシウム化合物を作製してもよい。なお、所定の条件を満たすマグネシア焼結体を入手可能な場合には、それを用いてもよい。 Si content can be adjusted with arbitrary additives. Although the additive is not particularly limited, examples thereof include silica fume, silica sand, and sodium silicate. Although it is possible to use a commercially available magnesium compound, it is also possible to prepare a magnesium compound whose components are adjusted using known means. Note that if a magnesia sintered body that satisfies predetermined conditions is available, it may be used.
マグネシア焼結体が粗大粒を多く含む場合には、粉砕により扱いやすい粒径とすることができる。粉砕装置としては、例えば、ハンマークラッシャー、ロールクラッシャー、ジョークラッシャー、衝撃式破砕機などの破砕装置、ディスクミル、転動ボールミル、振動ボールミル、ピンミル、ビーズミル、ジェットミル、サイクロンミルなどの粉砕装置等が挙げられる。こうした装置は、単独で、あるいは２種以上を組み合わせて用いることができる。 When the magnesia sintered body contains many coarse particles, it can be pulverized to a particle size that is easy to handle. Examples of crushing devices include crushing devices such as hammer crushers, roll crushers, jaw crushers, and impact crushers, and crushing devices such as disk mills, rolling ball mills, vibrating ball mills, pin mills, bead mills, jet mills, and cyclone mills. Can be mentioned. These devices can be used alone or in combination of two or more types.
粉砕後、分級を行うことにより、粗粉および／または微粉を取り除いて、好ましい粒度分布とすることができる。分級方法は特に限定されず、振動篩、風力分級機、サイクロン式分級機などを単独で、あるいは２種以上を組み合わせて用いることができる。 By performing classification after pulverization, coarse powder and/or fine powder can be removed to obtain a preferable particle size distribution. The classification method is not particularly limited, and a vibrating sieve, a wind classifier, a cyclone classifier, etc. can be used alone or in combination of two or more types.
マグネシア焼結体に対し、必要に応じて、上述したような粉砕および／または分級の処理を施して、所定の粒径に調整することができる。粉砕工程と分級工程は、マグネシア焼結体に応じて適宜組み合わせることができ、順番および回数は特に制限されない。分級工程と粉砕工程とは、いずれを先に実施してもよく、粉砕工程を経たマグネシア焼結体に分級工程を実施した後、さらに粉砕工程を実施することもできる。 If necessary, the magnesia sintered body can be subjected to the above-described pulverization and/or classification treatment to adjust it to a predetermined particle size. The pulverizing step and the classifying step can be appropriately combined depending on the magnesia sintered body, and the order and number of times are not particularly limited. Either of the classification step and the pulverization step may be performed first, and the pulverization step may be further performed after the classification step is performed on the magnesia sintered body that has undergone the pulverization step.
採用するマグネシア焼結体の粒径が既に所望の性状を充足する場合は、粉砕工程および分級工程を実施することなく使用してもよい。
結晶子径、ＢＥＴ比表面積、およびＭｇＯ含有率の条件を備えたＭｇＯ粒子であれば、本発明のアルカリ剤として有効に用いることができる。適度な溶出速度を有し、長期にわたって安定した効果を発揮可能であるので、本発明の材料は、アルカリ剤として好適に用いることができる。
If the particle size of the magnesia sintered body already satisfies the desired properties, the magnesia sintered body may be used without performing the pulverization process and the classification process.
MgO particles that meet the conditions of crystallite diameter, BET specific surface area, and MgO content can be effectively used as the alkali agent of the present invention. The material of the present invention can be suitably used as an alkaline agent because it has an appropriate elution rate and can exhibit stable effects over a long period of time.
以下、本発明を実施例に基づいて具体的に説明するが、これらは本発明の目的を限定するものではなく、また、本発明は、これら実施例に限定されるものではない。 Hereinafter, the present invention will be specifically explained based on Examples, but these do not limit the purpose of the present invention, and the present invention is not limited to these Examples.
＜酸化マグネシウムの製造＞
原料のマグネシウム化合物としては、海水と消石灰の反応により得られた水酸化マグネシウムを用意した。水酸化マグネシウムにおける成分含有量は、消石灰からの不純物、不純物除去工程の有無、および添加剤により決定される。
水酸化マグネシウムを焼成してマグネシア焼結体を作製し、粉砕および分級を組み合わせて実施例および比較例となるＭｇＯ粒子を製造した。ＭｇＯ粒子を製造に当たっては、結晶子径およびＢＥＴ比表面積が表１の値となるように、焼結温度、および粉砕・分級を制御した。焼成温度、および粉砕・分級の有無は表１に示す通りである。粉砕１では衝撃式破砕機およびサイクロンミル、分級は篩別および風力選別、粉砕２ではサイクロンミルを用いた。
<Manufacture of magnesium oxide>
As a raw material magnesium compound, magnesium hydroxide obtained by a reaction between seawater and slaked lime was prepared. The component content in magnesium hydroxide is determined by impurities from slaked lime, presence or absence of an impurity removal process, and additives.
Magnesium hydroxide was fired to produce a magnesia sintered body, and MgO particles serving as Examples and Comparative Examples were produced by combining pulverization and classification. In producing MgO particles, the sintering temperature and crushing/classification were controlled so that the crystallite diameter and BET specific surface area became the values shown in Table 1. The firing temperature and the presence or absence of crushing and classification are shown in Table 1. For crushing 1, an impact crusher and a cyclone mill were used, for classification, sieving and wind sorting were used, and for crushing 2, a cyclone mill was used.
得られたＭｇＯ粒子について、結晶子径、ＢＥＴ比表面積、含有成分、および体積累積粒径を求めた。それぞれの評価方法は、以下のとおりである。 Regarding the obtained MgO particles, the crystallite diameter, BET specific surface area, contained components, and volume cumulative particle size were determined. The evaluation methods for each are as follows.
＜結晶子径＞
まず、Ｘ線回折装置（ブルカー・エイエックスエス社製 ＮＥＷ Ｄ８ ＡＤＶＡＮＣＥ）を用い、以下の条件にてＸＲＤパターンを求めた。
Ｘ線源：ＣｕＫα（Ｎｉフィルター）
管電圧：４０ｋＶ
管電流：４０ｍＡ
検出器：１次元半導体高速検出器 ＬｙｎｘＥｙｅ
発散スリット：０．３０度
ステップサイズ：０．０１５度
計数時間：０．６５秒／ステップ
得られたＸＲＤパターンについて、解析ソフト（ブルカー・エイエックスエス社製 ＤＩＦＦＲＡＣ．ＥＶＡ Ｖ．３．２）を用いて、結晶子径を算出した。ＸＲＤパターン中のＭｇＯ（００２）面ピークを指定し、半値幅に基づく結晶子径として計算された値を用いた。
<Crystallite diameter>
First, an XRD pattern was obtained using an X-ray diffraction device (NEW D8 ADVANCE manufactured by Bruker AXS) under the following conditions.
X-ray source: CuKα (Ni filter)
Tube voltage: 40kV
Tube current: 40mA
Detector: One-dimensional semiconductor high-speed detector LynxEye
Divergence slit: 0.30 degrees Step size: 0.015 degrees Counting time: 0.65 seconds/step The obtained XRD pattern was analyzed using analysis software (DIFFRAC.EVA V.3.2, manufactured by Bruker AXS). The crystallite diameter was calculated using The MgO (002) plane peak in the XRD pattern was specified, and the value calculated as the crystallite diameter based on the half width was used.
＜ＢＥＴ比表面積＞
比表面積計（ユアサイオニクス株式会社製、モノソーブ）を用いて、前処理として１８０℃で１０分間脱気後、ＢＥＴ１点法にて測定した。
<BET specific surface area>
Using a specific surface area meter (Monosorb, manufactured by Your Scionics Co., Ltd.), the sample was degassed at 180° C. for 10 minutes as a pretreatment, and then measured by the BET one-point method.
＜含有成分の測定＞
ＭｇＯ粒子の含有成分は、四ホウ酸リチウムを融材としたガラスビード法を用いて、蛍光Ｘ線分析装置（リガク製Ｓｕｐｅｒｍｉｎｉ ２００）により測定した。検出された特性Ｘ線の定量分析には、耐火物協会標準物質蛍光Ｘ線分析用マグネシア質耐火物（ＪＲＲＭ４０１－４１０）から作成した検量線を用いた。
<Measurement of contained components>
The components contained in the MgO particles were measured using a fluorescent X-ray analyzer (Supermini 200 manufactured by Rigaku) using a glass bead method using lithium tetraborate as a flux. For quantitative analysis of the detected characteristic X-rays, a calibration curve prepared from the Refractory Association standard material magnesia refractory for fluorescent X-ray analysis (JRRM401-410) was used.
蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に変換した際の含有率（質量％）合計を１００としたときのＳｉＯ２含有率およびＭｇＯ含有率を、それぞれＸＲＦ（Ｓ）およびＸＲＦ（Ｍ）とした。こうして得られたＸＲＦ（Ｓ）およびＸＲＦ（Ｍ）を用いて、下記式（１）によりＳ／Ｍ比を求めた。
Ｓ／Ｍ＝ＸＲＦ（Ｓ）／ＸＲＦ（Ｍ） （１）
得られた結果を、結晶子径およびＢＥＴ比表面積とともに下記表１にまとめる。
The content (mass%) when the five elements Mg, Ca , Si , Fe , and Al detected by fluorescent ) The SiO 2 content rate and the MgO content rate when the total was 100 were defined as XRF (S) and XRF (M), respectively. Using the XRF(S) and XRF(M) thus obtained, the S/M ratio was determined by the following formula (1).
S/M=XRF(S)/XRF(M) (1)
The obtained results are summarized in Table 1 below along with the crystallite diameter and BET specific surface area.
＜体積累積粒径（Ｄ５０）＞
レーザー回折式粒度分布測定装置（ＭＩＣＲＯＴＲＡＣ ＭＴ３３００ＥＸ マイクロトラック・ベル（株）製）により、波長７８０ｎｍのレーザー光を用い、３回の繰り返し測定の平均として体積基準の粒度分布を求め、５０％体積累積粒径Ｄ５０を得た。
得られた結果を、Ｄ５０／結晶子径とともに下記表２にまとめる。
<Volume cumulative particle size (D50)>
Using a laser diffraction particle size distribution analyzer (MICROTRAC MT3300EX, manufactured by Microtrac Bell Co., Ltd.), a volume-based particle size distribution was determined as the average of three repeated measurements using a laser beam with a wavelength of 780 nm, and a 50% volume cumulative particle size distribution was obtained. A diameter D50 was obtained.
The obtained results are summarized in Table 2 below along with D50/crystallite diameter.
実施例のＭｇＯ粒子は、いずれも結晶子径が８０～３００ｎｍ、ＢＥＴ比表面積が０．１～１．２ｍ２／ｇ、ＭｇＯ含有率が９５質量％以上である。これに対し、比較例１のＭｇＯ粒子は、結晶子径が８０ｎｍ未満であり、比較例２，３のＭｇＯ粒子は、ＢＥＴ比表面積が１．２ｍ２／ｇを超えている。 The MgO particles of Examples all have a crystallite diameter of 80 to 300 nm, a BET specific surface area of 0.1 to 1.2 m 2 /g, and an MgO content of 95% by mass or more. On the other hand, the MgO particles of Comparative Example 1 have a crystallite diameter of less than 80 nm, and the MgO particles of Comparative Examples 2 and 3 have a BET specific surface area of more than 1.2 m 2 /g.
実施例および比較例のＭｇＯ粒子について、溶出性および耐湿性を評価した。それらの方法を以下に示す。 The MgO particles of Examples and Comparative Examples were evaluated for elution property and moisture resistance. Those methods are shown below.
＜溶出速度試験＞
まず、５０ｍｇのＭｇＯ粒子を１００ｍＬのイオン交換水に分散して、ＭｇＯ懸濁液を調製した。電位差自動滴定装置（京都電子工業製、ＡＴ－５１０型）を用い、ＭｇＯ懸濁液を撹拌しつつ０．０５ｍｏｌ／Ｌの硫酸を滴下することでＭｇＯ懸濁液のｐＨを３に保持し、ｐＨ維持に要した硫酸消費量（ＣＳ(1)）（硫酸ｍｏｌ／ＭｇＯｍｏｌ）を求めた。測定の終点は、測定開始から１時間経過、もしくは硫酸消費量から懸濁液中のＭｇＯ全量を消費したと判定される時点とし、測定開始～終点までの時間を滴定時間（ｓ）とした。
イオン交換水１００ｍＬについて同様に測定し、ブランクの硫酸消費量（ＣＳ(0)）（硫酸ｍｏｌ／ＭｇＯｍｏｌ）を求めた。酸化マグネシウム懸濁液の終点時間における硫酸消費量（ＣＳ(1)）（硫酸ｍｏｌ／ＭｇＯｍｏｌ）から、ブランクでの終点時間における硫酸消費量（ＣＳ(0)）（硫酸ｍｏｌ／ＭｇＯｍｏｌ）を差し引き、酸化マグネシウム粉末による（終点における硫酸ｍｏｌ／ＭｇＯｍｏｌ）を求めた。
こうして得られた（終点における硫酸ｍｏｌ／ＭｇＯｍｏｌ）をｍとし、滴定時間（ｓ）をｔとして、下記式（２）により溶出速度試験値Ｘを算出する。
Ｘ＝ｍ／ｔ （２）
溶出速度試験値Ｘが０．０００３５以下であれば、適度な溶出速度を備えている。
<Elution rate test>
First, 50 mg of MgO particles were dispersed in 100 mL of ion-exchanged water to prepare an MgO suspension. Using a potentiometric automatic titrator (manufactured by Kyoto Denshi Kogyo, AT-510 type), the pH of the MgO suspension was maintained at 3 by dropping 0.05 mol/L of sulfuric acid while stirring the MgO suspension. The amount of sulfuric acid consumed (CS(1)) (sulfuric acid mol/MgOmol) required for pH maintenance was determined. The end point of the measurement was one hour after the start of the measurement, or the time when it was determined that the entire amount of MgO in the suspension had been consumed from the amount of sulfuric acid consumed, and the time from the start of the measurement to the end point was taken as the titration time (s).
A similar measurement was made for 100 mL of ion-exchanged water to determine the blank sulfuric acid consumption (CS(0)) (sulfuric acid mol/MgOmol). Subtract the sulfuric acid consumption amount (CS(0)) (sulfuric acid mol/MgOmol) at the end point time of the blank from the sulfuric acid consumption amount (CS(1)) (sulfuric acid mol/MgOmol) at the end point time of the magnesium oxide suspension, (Sulfuric acid mol/MgOmol at the end point) was determined using magnesium oxide powder.
The elution rate test value X is calculated by the following formula (2), where m is the thus obtained (sulfuric acid mol/MgOmol at the end point) and t is the titration time (s).
X=m/t (2)
If the elution rate test value X is 0.00035 or less, it has an appropriate elution rate.
＜耐湿性試験＞
２０ｇのＭｇＯ粒子をガラス製秤量瓶に収容して秤量し、温度５０℃及び湿度８５％の恒温恒湿槽中で１２０時間保持した。その後、恒温恒湿槽から取り出し、ＭｇＯ粒子の質量（Ｍ(1)）を秤量し、保持前のＭｇＯ粒子の質量（Ｍ(0)）を用いて下記式により重量増加率を求めた。質量増加率が２％以下であれば、十分な耐湿性を備えている。
質量増加率＝（（Ｍ(1)－Ｍ(0)）／Ｍ(0)）×１００（％）
得られた結果を、溶解速度試験値とともに下記表３にまとめる。
<Moisture resistance test>
20 g of MgO particles were placed in a glass weighing bottle, weighed, and kept in a constant temperature and humidity chamber at a temperature of 50° C. and a humidity of 85% for 120 hours. Thereafter, it was taken out from the constant temperature and humidity chamber, the mass of the MgO particles (M(1)) was weighed, and the weight increase rate was determined by the following formula using the mass of the MgO particles before holding (M(0)). If the mass increase rate is 2% or less, it has sufficient moisture resistance.
Mass increase rate = ((M(1)-M(0))/M(0))×100(%)
The results obtained are summarized in Table 3 below along with the dissolution rate test values.
実施例のＭｇＯ粒子は、結晶子径が８０～３００ｎｍ、ＢＥＴ比表面積が０．１～１．２ｍ２／ｇの範囲内であるので、適度な溶出速度を有している。これに対し、ＭｇＯ粒子は、結晶子径が８０ｎｍ未満と小さい比較例１、ＢＥＴ比表面積が１．２ｍ２／ｇを超えている比較例２，３では、溶出速度が過剰に早くなる。結晶子径およびＢＥＴ比表面積の一方の要件を備えない場合には、長期にわたって機能を発現することができない。 The MgO particles of the examples have a crystallite diameter of 80 to 300 nm and a BET specific surface area of 0.1 to 1.2 m 2 /g, so they have an appropriate elution rate. On the other hand, the elution rate of MgO particles becomes excessively fast in Comparative Example 1, which has a small crystallite diameter of less than 80 nm, and Comparative Examples 2 and 3, which have a BET specific surface area of more than 1.2 m 2 /g. If one of the requirements of crystallite diameter and BET specific surface area is not met, functions cannot be expressed over a long period of time.
Claims (4)
（ＭｇＯ含有率は、蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に変換した際の含有率（質量％）合計を１００としたときの値である。） The crystallite diameter is 80 to 300 nm, the BET specific surface area is 0.1 to 1.2 m 2 /g , the MgO content is 95.0% by mass or more, and the 50% volume cumulative particle size (D50) is 1 to 1.2 m 2 /g. An alkaline agent characterized by containing magnesium oxide particles having a size of 200 μm .
(MgO content is calculated when the five elements Mg, Ca, Si, Fe, and Al detected by fluorescent X-ray measurement are converted into MgO, CaO, SiO 2 , Fe 2 O 3 , and Al 2 O 3 respectively. This is the value when the total content (mass%) of is 100.)
Ｓ／Ｍ＝ＸＲＦ（Ｓ）／ＸＲＦ（Ｍ） （１）
（ＸＲＦ（Ｓ）およびＸＲＦ（Ｍ）は、それぞれ、蛍光Ｘ線測定にて検出されたＭｇ，Ｃａ，Ｓｉ，Ｆｅ，Ａｌの５元素を、それぞれＭｇＯ、ＣａＯ、ＳｉＯ２、Ｆｅ２Ｏ３、Ａｌ２Ｏ３に変換した際の含有率（質量％）合計を１００としたときのＳｉＯ２含有率およびＭｇＯ含有率である。） The alkaline agent according to claim 1, wherein the magnesium oxide particles have an S/M ratio expressed by the following formula (1) of 0.004 to 0.040.
S/M=XRF(S)/XRF(M) (1)
(XRF(S) and XRF(M) respectively convert the five elements Mg, Ca, Si, Fe, and Al detected by fluorescent X-ray measurement into MgO, CaO, SiO 2 , Fe 2 O 3 , These are the SiO 2 content and MgO content when the total content (mass%) when converted to Al 2 O 3 is 100.)
Ｘ＝ｍ／ｔ （２）
（上記式（２）中、ｍは、ＭｇＯ懸濁液のｐＨを３に維持する溶出試験の（終点における硫酸ｍｏｌ／ＭｇＯ ｍｏｌ）であり、ｔは、滴定時間（ｓ）である。） The alkaline agent according to claim 1, wherein the magnesium oxide particles have an elution rate test value X expressed by the following formula (2) of 0.00003 or more and 0.00035 or less.
X=m/t (2)
(In the above formula (2), m is (sulfuric acid mol/MgO mol at the end point) of the elution test in which the pH of the MgO suspension is maintained at 3, and t is the titration time (s).)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2022119560A JP7382463B1 (en) | 2022-07-27 | 2022-07-27 | alkaline agent |
| PCT/JP2023/026983 WO2024024719A1 (en) | 2022-07-27 | 2023-07-24 | Alkali agent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2022119560A JP7382463B1 (en) | 2022-07-27 | 2022-07-27 | alkaline agent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP7382463B1 true JP7382463B1 (en) | 2023-11-16 |
| JP2024017122A JP2024017122A (en) | 2024-02-08 |
Family
ID=88729234
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2022119560A Active JP7382463B1 (en) | 2022-07-27 | 2022-07-27 | alkaline agent |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP7382463B1 (en) |
| WO (1) | WO2024024719A1 (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007084360A (en) | 2005-09-20 | 2007-04-05 | Ube Material Industries Ltd | Magnesium oxide powder for soil hardening material |
| JP2007161838A (en) | 2005-12-13 | 2007-06-28 | Ube Material Industries Ltd | Soil solidifier |
| JP2007161839A (en) | 2005-12-13 | 2007-06-28 | Ube Material Industries Ltd | Soil solidifier |
| JP2009114291A (en) | 2007-11-05 | 2009-05-28 | Terunaito:Kk | Heavy metal insolubilizer and heavy metal contaminated soil treatment agent |
| JP2011079919A (en) | 2009-10-05 | 2011-04-21 | Taiheiyo Cement Corp | Insolubilizing material |
| JP2012050911A (en) | 2010-08-31 | 2012-03-15 | Sumitomo Osaka Cement Co Ltd | Elution reducing material and method for producing the same |
| JP2018044110A (en) | 2016-09-16 | 2018-03-22 | 鹿島建設株式会社 | Soil modifier |
| WO2022138037A1 (en) | 2020-12-25 | 2022-06-30 | 宇部マテリアルズ株式会社 | Magnesium oxide powder, thermally conductive filler, resin composition, and production method for magnesium oxide powder |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10316967A (en) * | 1997-05-15 | 1998-12-02 | Katsuichi Kunimatsu | Soil solidification agent |
| JP4564647B2 (en) * | 2000-11-29 | 2010-10-20 | 松田技研工業株式会社 | Soil solidifying agent |
-
2022
- 2022-07-27 JP JP2022119560A patent/JP7382463B1/en active Active
-
2023
- 2023-07-24 WO PCT/JP2023/026983 patent/WO2024024719A1/en unknown
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007084360A (en) | 2005-09-20 | 2007-04-05 | Ube Material Industries Ltd | Magnesium oxide powder for soil hardening material |
| JP2007161838A (en) | 2005-12-13 | 2007-06-28 | Ube Material Industries Ltd | Soil solidifier |
| JP2007161839A (en) | 2005-12-13 | 2007-06-28 | Ube Material Industries Ltd | Soil solidifier |
| JP2009114291A (en) | 2007-11-05 | 2009-05-28 | Terunaito:Kk | Heavy metal insolubilizer and heavy metal contaminated soil treatment agent |
| JP2011079919A (en) | 2009-10-05 | 2011-04-21 | Taiheiyo Cement Corp | Insolubilizing material |
| JP2012050911A (en) | 2010-08-31 | 2012-03-15 | Sumitomo Osaka Cement Co Ltd | Elution reducing material and method for producing the same |
| JP2018044110A (en) | 2016-09-16 | 2018-03-22 | 鹿島建設株式会社 | Soil modifier |
| WO2022138037A1 (en) | 2020-12-25 | 2022-06-30 | 宇部マテリアルズ株式会社 | Magnesium oxide powder, thermally conductive filler, resin composition, and production method for magnesium oxide powder |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2024024719A1 (en) | 2024-02-01 |
| JP2024017122A (en) | 2024-02-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7454334B2 (en) | Method for manufacturing magnesium oxide and grain-oriented electrical steel sheet for annealing separator | |
| EP3438292B1 (en) | Magnesium oxide for annealing separators, and grain-oriented magnetic steel sheet | |
| EP3438324B1 (en) | Magnesium oxide for annealing separators, and grain-oriented magnetic steel sheet | |
| CN111186850B (en) | Magnesium oxide for oriented silicon steel annealing separant and preparation method thereof | |
| EP3438291B1 (en) | Magnesium oxide for annealing separator, and grain-oriented electromagnetic steel sheet | |
| JP6277334B1 (en) | Magnesium oxide powder and method for producing the same | |
| JP7382463B1 (en) | alkaline agent | |
| JP7328777B2 (en) | Magnesium oxide for annealing separator containing magnesium titanate, method for producing the same, annealing separator, and grain-oriented electrical steel sheet | |
| JP7454335B2 (en) | Method for manufacturing magnesium oxide and grain-oriented electrical steel sheet for annealing separator | |
| JP6311220B2 (en) | Method for producing low-temperature fired cement clinker | |
| JP7360572B1 (en) | Magnesium oxide for annealing separator and grain-oriented electrical steel sheet | |
| EP3438295B1 (en) | Magnesium oxide for annealing separators, and grain-oriented magnetic steel sheet | |
| JP7181441B1 (en) | Magnesium oxide for annealing separator and grain-oriented electrical steel sheet | |
| JP2012162440A (en) | Gallium oxide powder | |
| JP2015193536A (en) | gallium oxide powder | |
| JP2002097458A (en) | Cerium-containing abrasive material, its quality inspection method and manufacturing method thereof | |
| JPS63195125A (en) | Barium ferrite magnetic powder and production thereof | |
| JP2003193117A (en) | Method of producing iron-rhodium magnetic powder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20230519 |
|
| A871 | Explanation of circumstances concerning accelerated examination |
Free format text: JAPANESE INTERMEDIATE CODE: A871 Effective date: 20230519 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230627 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20230810 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20231031 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20231106 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7382463 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |