Dried Aluminium Hydroxide
Aluminium hydroxide is a Al(OH)3 compound based on aluminium oxide and water, which is obtained as a white substance, showing amphoteric properties and low solubility in water. Freshly precipitated hydroxide can interact with acids and alkalines, which results in the formation of orthoaluminates, i.e. the salts of orthoaluminic acid, H3AlO3, or meta-aluminates, i.e. the salts of meta-aluminic acid,HAlO2.
Dried aluminium hydroxide looks like a white crystalline substance, non-soluble in alkali and acids.
The Properties and Application of Dried Aluminium Hydroxide
Owing to its ability to adsorb various substances, aluminium hydroxide is used in water treatment. It also acts as an adjuvant for medical vaccine production and as an antacid. This compound is applied as a fire retarder in plastic and many other materials. It absorbs heat, inhibits burning, adsorbs flammable gases, excludes polymer heating and decomposition and reduces combustibility of materials.
For industrial purposes, dried aluminium hydroxide acts as a mineral filler in the production of plastics. It is used as a fine-dispersed filler for the manufacturing of paint coatings, as a pigment substitute, as a hardening and curing accelerator in dry and mortar construction mixes. Thermochemically-activated hydroxide can be used as a carrier, i.e. a structure-forming element for the production of hydrotreatment and reforming catalysts, as well as desiccants and sorbents.
Dried aluminium hydroxide is used as a filler in the production of refractories, abrasives, sealants, glues, and polishing pastes. The compound has found usage in the glass-making, rubber-making and chemical industries, the production of special-purpose wearproof, engineering and electric-grade ceramics.
Production of Dried Aluminium Hydroxide
Currently, the most common method of aluminium hydroxide production is the Bayer’s method, which belongs to hydrochemical alkali processes and consists in hydrolysis of aluminate liquors giving aluminium hydroxide in the form of crystalline residue. Dried aluminium hydroxide is produced by means of filtration, washing and evaporation of the resulting residue till a dry substance is obtained.
The use of various types of aluminium hydroxides and special technologies of heat treatment, drying, grinding, milling, screening and calcination make it possible to obtain a wide range of special-purpose materials having required properties. Microintech has state-of-the-art process lines to develop and produce the required volumes of dried aluminium hydroxide-based products, which meet the customized demands of any production facility in terms of all crucial physical and chemical characteristics.