The sepiolite is a lightweight porous mineral which is rich in the nature. The silicate mineral of the magnesium fiber that functions as a suspending aid in salt-water based spacers and it can absorb approximately its own weight of water and other liquids without the granules break down when thoroughly soaked. Once spreaded in the liquid spacer system using a high-shear mixer, sepiolite catches the liquid, increasing the viscosity of the suspension. This structure is stable even in systems with high salt concentrations. Sepiolite has been known since ancient ages such as Roman Empire when it was used to filter and purify wine, but our understanding at the atomic scale of how these tiny crystals absorb enormous amounts of liquid has remained mysterious until now. The unusual properties of this clay make it a highly requested after mineral, despite its shortage in the Earth’s crust: only a few mines worldwide extract it. Sepiolite is nontoxic and odorless. Its melting point is 1500-1700 ℃. It dissolves in hydrochloric acid.
No other mineral is known to absorb more water or other liquids as efficiently as sepiolites so far. The reasons are its structural nanoporosity due to channels in the crystals, and the fact that the elongated, needle-shaped sepiolite crystals pack very loosely into a lightweight porous material. The surface area ranges between 75 and 400 m2/g, meaning that 20g of mineral have an internal surface equivalent to that of a football court. This is why sepiolite can absorb more than its weight in water. The channels in the crystal structure along with the empty space between the needles form a capillary network through which liquids can easily flow deep inside the bulk where the molecules attach to the surface of the crystals. Today, no synthetic clay exceeds natural sepiolite. This is about to change as our understanding of their atomic structure will guide the synthesis of sepiolites from other, more abundant clay minerals and the design of completely new materials for use in catalysis and batteries. Sepiolite absorbs liquid spillages and odours and stabilise aqueous products like paints, resins and inks. they could also bind food products and stabilise drugs, extending their shelf life and making sepiolite an edible product in synthetic form.
Uses of Sepiolite
Building material: Supporting rockwool in a building insulation, interlaminar bonding of calcium silicate boards and viscosity conditioning of the exterior walls
Flame retardant paper: Mixed with glass fibre, sepiolite can be turn into an inorganic noncombustible paper.
Automobile: Damping material and viscosity conditioning
Pet Litter: Sepiolite is lightweight and convenient to be utilised as a low maintenance solution for most households.
Animal Feed: Its properties; free flow, anticaking, chemical inertia and atoxicity makes sepiolite outstanding for use as; growth promoters, carrier of supplements, binder of feed. It is a superior binder for all kinds of feed from the very fatty types to fibrous depending on the specie of animal.
Agriculture: Soil conditioning, fluid carriers, seed coatings, fertiliser suspensions, phytosanitary suspensions.
Paint/coating and adhesive: Thickener
Industrial Absorbents: It is a perfect floor absorbents to remove oily substances causing slipperiness. Sepiolite has a sorptive capacity much greater than that of any other clay and coupled with its mechanical resistance preventing distribution even when fully sokaed, permits its use in granular forms as an absorbent of water, oils and other liquids. More importantly, sepiolite is chemically inert, non-combustible and non-inflammatory.
Various uses of sepiolite: Using in purifying oils, making medical casing and organic coolant in refining atomic reactor in order to absorb radioactive waste. The processed sepiolite mixed with some active carbon in an ideal substance in making filter tip of cigarettes. Mixing with cement, it helps to reduce contraction and leave no gaps and leak no water. Adding in paint,and the quality of the paint will improve .A very fine mud material in well drilling for terrestrial heat, for petroleum and halite. It is applied in deep well drilling particularly. Making soap and detergent in place of fatty acid, so that it improves its quality and clearance. In cosmetic industry , it is used in absorbing the bacteria.