Magnesium hydroxide is primarily used in inorganic flame retardants (for plastics, rubber, and cables), pharmaceutical applications (as an antacid and laxative), environmental protection (desulfurization and wastewater neutralization), and as a chemical raw material.
Flame Retardant and Filler Material: As an eco-friendly inorganic flame retardant, it is widely used in plastics (such as PE, PP, PVC, and EVA) and rubber products, as well as in low-smoke, halogen-free cable sheathing. Upon heating and decomposition (340–490°C), it absorbs heat and releases water vapor to suppress smoke; it forms a magnesium oxide coating that blocks oxygen and provides both filling and reinforcing effects.
Pharmaceuticals and Health: Taken orally as an antacid to neutralize gastric acid, it treats hyperacidity, heartburn, and occasional constipation. Due to its low water solubility and mild alkalinity, it causes minimal irritation to the gastric mucosa and is often combined with aluminum hydroxide to balance side effects.
Environmental Protection: It serves as a flue gas desulfurization agent (offering high efficiency and resistance to scaling compared to lime or caustic soda) and a neutralizing agent for acidic wastewater; it adjusts pH levels and adsorbs/precipitates heavy metal ions (such as lead and chromium) without causing secondary pollution.
Magnesium hydroxide is an excellent flame retardant for plastic and rubber products. In environmental applications, it acts as a flue gas desulfurization agent and can replace caustic soda or lime to neutralize acidic wastewater. It is also used as a fuel oil additive for anti-corrosion and desulfurization purposes. Additionally, it finds applications in the electronics industry, pharmaceuticals, sugar refining, thermal insulation materials, and the manufacture of other magnesium salt products.