Characteristics and Applications of Magnesium Chloride (Hexahydrate & Anhydrous)

I. Characteristics of Anhydrous and Hexahydrate Magnesium Chloride

II. Major Application Fields and Performance Manifestations

1. Building Materials Industry — Magnesium Oxychloride Cement Products

Performance manifested: gelling property, high strength, fire resistance and thermal insulation

· Applications: Production of magnesite cement, fireproof boards, partition boards, decorative panels, cable trays, ceramic binders

· Principle: Magnesium chloride reacts with magnesia (MgO) to form magnesium oxychloride cement, featuring early strength development, high strength, fire resistance, and thermal insulation. In some fireproof boards, magnesium chloride releases chlorine gas when heated at around 100–110°C, which helps extinguish fires.

· Selection: Anhydrous magnesium chloride, with its high purity and superior strength performance, is commonly used in high-end magnesite products requiring high strength. Some applications use magnesium chloride hexahydrate for relatively lower costs.

2. Road Snow and Ice Removal — De-Icing Agents

Performance manifested: low freezing point, high snow-melting efficiency, relatively low corrosivity

· Applications: Snow and ice removal on highways, urban roads, and airport runways

· Principle: The freezing point of magnesium chloride aqueous solution can drop below -30°C, enabling rapid melting of ice and snow

· Selection: Magnesium chloride hexahydrate has obvious cost advantages and is the mainstream choice for de-icing agents. Some de-icing agents are also made by mixing in specific proportions, containing ingredients such as calcium chloride, calcium magnesium acetate (CMA), and corrosion inhibitors.

3. Chemical Raw Material Production — Preparation of Magnesium Compounds

Performance manifested: chemical activity, source of magnesium ions

· Applications: Production of magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium sulfate, and other magnesium salt products

· Principle: Magnesium chloride is the basic raw material for preparing various magnesium compounds and can be converted into multiple magnesium products through chemical reactions

· Selection: Anhydrous magnesium chloride, with high purity, is suitable for preparing high-end magnesium chemicals; magnesium chloride hexahydrate is suitable for bulk magnesium salt production.

4. Metallurgical Industry — Magnesium Metal Smelting

Performance manifested: electrolytic properties, high purity

· Applications: Electrolytic production of magnesium metal

· Principle: Anhydrous magnesium chloride can be electrolyzed in molten state to produce magnesium metal and chlorine gas (MgCl₂(molten) → electrolysis → Mg + Cl₂↑)

· Selection: Anhydrous magnesium chloride must be used, with extremely low water content requirements.

5. Dust Control and Soil Stabilization

Performance manifested: hygroscopicity, cohesiveness

· Applications: Dust control on construction sites, mining areas, and roads; soil stabilizer

· Principle: After absorbing moisture, magnesium chloride forms a moist surface layer that effectively suppresses dust consolidates soil particles. In China, one method for foundation consolidation at some construction sites involves pouring and irrigating with large amounts of magnesium chloride hexahydrate aqueous solution.

6. Water Treatment Industry

Performance manifested: flocculation aid, pH adjustment

· Applications: Sewage treatment, wastewater purification

· Principle: Used as a flocculation aid in combination with other agents to improve precipitation efficiency

7. Food Industry (Food Grade)

Performance manifested: coagulation property, mineral supplementation

· Applications: Tofu coagulant (brine tofu), fish dehydrating agent, mineral supplement

· Principle: Magnesium chloride coagulates proteins and is the key coagulant in traditional tofu making

8. Aquaculture and Livestock Farming

Performance manifested: In aquaculture — magnesium supplementation and calcium regulation, water stabilization and algae cultivation, anti-stress effects; In livestock — meets magnesium requirements of cattle, sheep, and other livestock. In China, magnesium is also supplemented through mineral lick blocks, bean curd residue, and other feedstuffs.

· Applications: Magnesium supplementation in aquaculture water bodies for shrimp, crabs, and other aquatic products; regulation of water hardness

· Principle: Replenishes magnesium ions in water bodies, promotes algae growth, and enhances the anti-stress ability of aquatic animals.

Magnesium chloride is also used as a raw material in many other industries such as petroleum and various other sectors. We, as Yuze magnesium chloride manufacturer, will not elaborate further.

In our 13 years of specializing in magnesium chloride (hexahydrate and anhydrous), many customers already have clear product specifications — such as whether the content should be above 46% for magnesium chloride hexahydrate or above 98% for anhydrous magnesium chloride. Some have even more specific indicators, such as heavy metal content must be below a certain value, or sodium ions and sulfate ions must be below specific values.

If you would like to learn about specific industry applications or have already established specific standards, please feel free to contact us directly for consultation. Yuze Chemical will continue to update content related to magnesium chloride hexahydrate and anhydrous magnesium chloride in the future.