Vermiculite

Name:
Vermiculite
Detailed information:
Hydrated magnesium-iron-aluminum silicate capable of expanding 6–20 times when heated to 1093C. The platelets exhibit an active curling movement when heated, hence the name.

Occurrence:

Montana, North Carolina, South Carolina, Wyoming, Colorado, South Africa.

Properties:

Platelet-type crystalline structure. High porosity, high void volume to surface area ratio, low density, large range of particle size. Insoluble in water and organic solvents; soluble in hot concentrated sulfuric acid. Water vapor adsorption capacity of expanded vermiculite less than 1%, liquid adsorption dependent on conditions and particle size, ranges 200–500%. Noncombustible.

Grade:

Unexpanded (ore concentrate), expanded (also called exfoliated), flake, activated.

Use:

Lightweight concrete aggregate, insulation, sound conditioning, fireproofing, plaster, soil conditioner, additive for fertilizers, seed bed for plants, refractory, lubricant, oil-well drilling mud. Filler in rubber, paint, plastics. Wallpaper printing, removal of strontium-90 from milk, absorption of oil spills on seawater, animal feed additive, packing, carrier for insecticides, catalyst and catalyst support, litter for hatcheries, adsorbent.

See Verxite.