Diatomite, also known as diatomaceous earth, is a naturally occurring siliceous rock primarily composed of the fossilized remains of ancient diatoms, a type of microscopic, single-celled algae. These algae have siliceous shells that, when they die, accumulate at the bottom of water bodies and, over time, undergo geological processes to form diatomite deposits.
The main chemical composition of diatomite is SiO2, often accounting for over 80% of its content, with traces of other oxides such as Al2O3, Fe2O3, CaO, MgO, and organic impurities. Its unique physical properties include a high porosity (up to 90%), large specific surface area, and strong adsorption capacity, which are attributed to its microporous structure.
Diatomite is lightweight, soft, and porous, with a variety of colors ranging from white to grayish-white, light yellow, or even light brownish-gray. It has a high melting point, chemical stability, and is insoluble in hydrochloric acid but soluble in alkalis.
Due to its exceptional properties, diatomite is widely used in various industries. In agriculture, it serves as a natural fertilizer and soil conditioner, improving soil structure, air permeability, and water retention. In the construction industry, it is used as an insulating and heat-preserving material due to its good thermal insulation and hygroscopicity. Additionally, diatomite is an ideal filtering medium in water treatment, capable of removing suspended solids, heavy metal ions, bacteria, and organic pollutants.
