Bentonite – Aluminum Silicate (Al4 [Si6Al2O20](OH)4)2-.nH2O, which consists mostly of the mineral montomorillonite. It is valued for its ability to swell in water and to impart useful rheological properties to aqueous compositions. Bentonite consists of aggregates of flat platelets that have a high specific surface area, high plasticity, expand when wet; and is inert and non-toxic.
Highly Purified Surface Modified White Bentonite
Rio-Bent EW is suspending and thickening properties with pigments and extenders. It is excellent thixotropy for reducing sags & drips.Rio-Bent EW additive is highly beneficiated, easily dispersible white bentonite clay.
Properties & Markets
- Construction and Civil Engineering : Bentonite in civil engineering applications is traditionally used as a thixotropic, support and lubricant agent in diaphragm walls and foundations, in tunnelling, in horizontal directional drilling (HDD) and pipe jacking. Bentonite, due to its viscosity and plasticity, is also used in Portland cement and mortars.
- Environmental Markets : Bentonite’s adsorption / absorption properties are very useful for wastewater purification. EU directives recommend low permeability soils, which naturally should contain bentonite, as a sealing material in the construction and rehabilitation of landfills to ensure the protection of groundwater from the pollutants. Bentonite is the active protective layer of the Geosynthetic Clay Liners.
- Drilling : Another conventional use of bentonite is as a mud constituent for oil- and water- well drilling. Its role is mainly to seal the borehole walls, to remove drill cuttings and to lubricate the cutting head.
- Oils / Food Markets : Bentonite is utilised in the removal of impurities in oils where its adsorptive properties are crucial in the processing edible oils and fats (Soya / Palm / Canola Oil). In drinks such as beer, wine and mineral water and in products like sugar or honey, bentonite is used as a clarification agent.
- Agriculture : Bentonite is used as an animal feed supplement, as a pelletising aid in the production of the animal feed pellets, as well as a flow ability aid for unconsolidated feed ingredients such as soy meal. It is also used as an ion exchange for improvement and conditioning of the soil. When thermally treated, it can be used as a porous ceramic carrier for various herbicides and pesticides.
- Pharmaceuticals, Cosmetics and Medical Markets : Bentonite is used as filler in pharmaceuticals and due to its absorption/adsorption functions, allows paste formation. Such applications include industrial protective creams, calamine lotion, wet compresses, and antiirritants for eczema. In medicine, bentonite is used as an antidote in heavy metal poisoning. Personal care products such as mud packs, sunburn paint, baby and face powders, and face creams may all contain bentonite.
- Detergents : Laundry detergents and liquid hand cleansers/soaps rely on the inclusion of bentonite, in order to remove the impurities in solvents and to soften the fabrics.
- Paints, Dyes and Polishes : Due to its thixotropic properties, bentonite and organoclays function as a thickening and/or suspension agent in varnishes, and in water and solvent paints. Their adsorption property is appreciated for the finishing of indigo dying cloth and in dyes (lacquers for paints & wallpapers).
- Paper : Bentonite is crucial to paper making, where it is used in pitch control, i.e. absorption of wood resins that tend to obstruct the machines and to improve the efficiency of the conversion of pulp into paper as well as to improve the quality of the paper. Bentonite also offers useful de-inking properties for paper recycling. In addition, acid activated bentonite is used as the active component in the manufacture of carbon less copy paper.
- Catalyst : Chemically modified clay catalysts find application in a diverse range of duties where acid catalysis is a key mechanism. Most particularly they are employed in the alkylation processes to produce fuel additives.