Magnesium Chloride

Magnesium chloride is an inorganic compound represented by the formula MgCl2, and it exists in various hydrated forms. Anhydrous MgCl2 contains approximately 25.5% elemental magnesium by mass. The hydrated forms of magnesium chloride can be obtained from brine or seawater sources. In its natural mineral state, known as bischofite, it is extracted through solution mining from ancient seabeds, such as the Zechstein seabed in northwest Europe. Anhydrous magnesium chloride serves as the primary precursor for the production of magnesium metal, while hydrated magnesium chloride is the more readily accessible form.

Synonyms: Magnesium dichloride, Magnesium(2+) dichloride, E511
Chemical Formula: MgCl2
CAS Number: 7786-30-3 (anhydrous), 7791-18-6 (hexahydrate)

Characteristics

Molar Weight: 203.3 g/mol (hexahydrate)

Melting Point: 118°C (hexahydrate)

Boiling Point: 1,412°C (anhydrous)

Flash Point: non flammable

Density: 1.569 g/cm³ (hexahydrate)

Forms: Liquid, White, Crystalline

Uses and applications

Key applications

Plastics and polymers
Wastewater treatment
Food additive
Water treatment
Agricultural
Pharmaceuticals
Household industrial
Animal feed
Cosmetic products
Medical products

Industries

Magnesium chloride

Magnesium chloride is the magnesium salt of hydrochloric acid. In nature, it is mainly found in salt deposits, salt lakes - for example in the Dead Sea - and seawater. Magnesium chloride also occurs naturally in the form of minerals such as bischofite. Bischofite often forms in underground salt deposits and is a secondary mineral that forms from evaporated seawater. Magnesium chloride is also present in the form of carnallite, a hydrated double salt of potassium chloride, which is formed by the evaporation of seawater or salt lakes and is often found in evaporite deposits.

Happy female runner holding water bottle with a sport drink

Magnesiumchlorid in der Industrie

Food

Magnesium chloride is used in various ways in the food industry under the name E511. It acts as a dietary supplement that increases the magnesium content in foods and drinks, for example in dietary products, mineral water and sports drinks.

Magnesium chloride is hygroscopic, it attracts moisture and is used in the food industry to protect products such as baked goods from drying out. It is also used as a coagulant in tofu production, where it is often referred to as "nigari". It is added to the soy milk to cross-link the proteins into the solid components of the tofu. The taste of certain specialties is adjusted by magnesium chloride, giving them a slightly bitter, salty note. In some applications, magnesium chloride is used as a preservative, particularly in solutions or as a component of marinades.

Agriculture

Magnesium chloride is used in agriculture primarily as a source of magnesium in fertilizers, an essential element for plant growth. It is also used to improve soil structure. It is also used as a food supplement for livestock.

Pharma

Magnesium chloride is used in the pharmaceutical industry as a dietary supplement to treat magnesium deficiency (hypomagnesemia), to help with muscle cramps, fatigue and stress, and to promote bone and heart health.

It also regulates the electrolyte balance and is used as a laxative. Dermatologically, it is used in bath additives and magnesium oil to reduce muscle tension and joint pain and soothe skin irritations. It is also used to treat skin problems such as acne, eczema and psoriasis. It has antimicrobial properties and is also used in solutions to disinfect wounds Magnesium chloride supplements are also used to support conditions such as osteoporosis, diabetes and migraines, as magnesium plays an important role in numerous biochemical processes in the body.

Cosmetics

Magnesium chloride has a hygroscopic effect and hydrates the skin in moisturizing creams, lotions and serums. The substance also has anti-inflammatory and soothing properties and is used by the cosmetics industry in after-sun lotions, for example, to reduce redness and relieve itching. Magnesium chloride removes impurities in peelings, masks and cleansing products. It is also used in anti-ageing products as it supports the regeneration of skin cells and combats free radicals. In hair care, magnesium chloride soothes the scalp and strengthens the hair structure. It has a relaxing effect in wellness products such as baths and aromatherapy applications.

Cleaning

Magnesium chloride is used as a de-icing agent for floors and surfaces such as roads, sidewalks and parking lots. It is less corrosive than conventional road salt (sodium chloride).

It is also used as a dust control agent, especially when cleaning large outdoor areas such as construction sites, storage areas, industrial plants or unpaved roads. It attracts moisture from the air and keeps dust particles bound to the ground.

Magnesium chloride regulates the pH value of cleaning agents. In all-purpose cleaners for household and commercial use, it supports the removal of grease and dirt.

Magnesium chloride is used in the cleaning of industrial plants to remove deposits such as calcium carbonate or magnesium sulphate from pipes, heat exchangers and other systems. In swimming pools, it prevents the formation of algae and makes it easier to clean the pool surface.

Water Treatment

Magnesium chloride plays a central role in water treatment, both in drinking water and wastewater treatment. It is used as a flocculant to remove impurities, promotes the growth of microorganisms in biological sewage treatment plants and lowers water hardness, thereby reducing limescale deposits. It also reduces the sulphate content, stabilizes the pH value, prevents corrosion and removes heavy metals. It is used in industry, groundwater remediation, seawater desalination and in swimming pools and drinking water networks.

Construction

Magnesium chloride has many uses in the construction industry, for example in the production of magnesium oxide cement for solid, fire-resistant and waterproof construction elements and as a concrete additive to improve strength, density and water resistance. It increases the stability of bricks, is used for soil stabilization and dust reduction on construction sites and protects metal structures from corrosion through coatings. It is also used in fire protection coatings.

Plastics and polymers

Magnesium chloride is an indispensable material in the plastics and polymer industry. It acts as a catalyst in the polymerization of polyolefins such as polyethylene (PE) and polypropylene (PP), which are required in the manufacture of packaging materials and in the production of fibres and plastics for automotive and household products.

It also serves as an additive for modifying plastic properties and is used in the production of composite materials, for example for lightweight and stable components for the automotive and aerospace industries, and flame retardants. Magnesium chloride is also used in the production of synthetic rubber for tires, seals and hoses.

Lubricants

Magnesium chloride is used in the lubricant industry as an additive to improve lubrication performance, corrosion protection, high temperature stability, moisture resistance and adhesion properties. It is used in lubricants for precision machinery as well as for automotive, aviation and industrial applications. It is also used in the production of metal soaps, which are used as thickeners in high-performance lubricating greases, particularly for the marine and offshore industries.

Further areas of application

Magnesium chloride is a versatile material that plays an important role in chemical processing. It is used both as a raw material and as an auxiliary material in various chemical processes. For example, it is used in the production of magnesium for lightweight construction applications, such as in the automotive and aviation industries, and magnesium compounds such as magnesium oxide for the light metals industry and the production of refractory materials.

Magnesium chloride is also used as a raw material for the production of other chlorine compounds such as potassium chloride and calcium chloride.

Due to its hygroscopic nature, it is also required to bind water from chemical reactions or from the environment. It acts as a drying agent in chemical processes and is used to regulate humidity in laboratory applications.

Magnesium chloride also regulates the pH value in chemical reactions. It is used in the chemical industry to remove sulphur compounds from raw materials such as oil and gas. It is also used in the production of fluxes for soldering and welding processes and as a reducing agent in metallurgy.