Magnesium hydroxide
Magnesium hydroxide is a weak base ionic compound.
It has extremely low water solubility that once mixed with water, the fluid becomes supersaturated and turns white like milk. Because of that, it has a nickname, Milk of Magnesia.
Magnesium hydroxide is often used as a main ingredient of antacid, and inhibits absorption of folic acid, iron, and potassium.
Magnesium hydroxide rocks are called Brucite.
It has extremely low water solubility that once mixed with water, the fluid becomes supersaturated and turns white like milk. Because of that, it has a nickname, Milk of Magnesia.
Magnesium hydroxide is often used as a main ingredient of antacid, and inhibits absorption of folic acid, iron, and potassium.
Magnesium hydroxide rocks are called Brucite.
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Characteristics
- Greater neutralization potential than other counteragents
(sodium hydroxide and calcium hydroxide, etc.) - Cheaper price by more than 50% and high cost-effectiveness
- Little sludge after neutralization thanks to the high solubility of salt
- Greater neutralization potential than other counteragents
Manufacturing Process
Magnesium hydroxide is obtained by applying alkali hydroxides to magnesium salt. It is precipitated in colloidal form.MgO(s) + H₂O(l) Mg(OH)₂(aq)
For industrial purposes,it is obtained from Brucite or by reaction using sea water for bulk production.
Industrial Use/Application
Since magnesium hydroxide is harmless to human body, it is used to neutralize acidic waste water.Magnesium hydroxide is also used to make artificial coral as it is a key ingredient of coral, along with calcium hydroxide.
Its high endothermic decomposition point of 332oC raises ignition point up and inhibits smoke when added to other matter for reaction.
Upon combustion, magnesium hydroxide absorbs oxygen to form water and eliminates flammable matters.
Because of such characteristics, it is used as coating of plastic items and roof, etc.
| Effect | Appearance |
|---|---|
| - Much excellent waste water neutralizing effect than other counteragent - Reasonable price with great cost effectiveness - No sludge occurrence thanks to high dissolving point |
Counteragent for acidic waste water (sulfuric acid, hydrochloric acid, and nitric acid) |
General Characteristics
| IUPAC name | Magnesium Hydroxide |
|---|---|
| Chemical formula | H₂MgO₂ |
| Molecular formula | Mg(OH)₂ |
| Other name | Milk of magnesia |
| CAS No. | 1309-42-8 |
| PubChem | PubChem 14791 |
| ChemSpider | 21169899 14107, 21169899 |
Physical Properties
| State | Hexagonal solid crystal |
|---|---|
| Molecular weight | 58.3197 g/mol |
| Melting point | 623.15 K (350 °C, 662 °F) |
| Density | 2.3446 g/cm3 |
| Experimental water solubility | 2.3446 g/cm3, 0.004 (100 °C) g/100 ml |
| Color | White |
| Ignition point | Nonflammable |
Stability
EU : Not on list / Risk Phrases
Product Standard
| Category | Unit | Standard | Note |
|---|---|---|---|
| Mg(OH)2 | % | 25.0 ~ 35.0 | |
| CaO | % | 1.50 max | |
| Acid insoluble | % | 2.0 max | |
| R2O3(Al2O3+Fe2O3) | % | 1.0 max | |
| Granularity | ㎛ | 10㎛ or less and 90% and more |
* Packing unit : Tank Lorry