What is vermiculite made of?

Question

What is vermiculite made of?

Answer 1

It's a mica-clay-like mineral, an aluminosilicate that forms in sheets.  It is an expandable mineral and thus is used for insulation and fireproofing quite frequently.  It also can accept water into its structure and thus may be used in packing when shipping bottled liquids, it acts as padding and provides a bit of an adsorption backup in case of leaks..

What is called vermiculite may not be pure vermiculite, though.  If you have vermiculite insulation in your house, it may contain asbestos as well.

Answer 2

DON'T KNOW

Answer 3

Hydrated basaltic mineral or form of mica or hydrated laminar magnesium aluminum silicate. In other words don't breate it in. A soil amendment good for clay soils. An interesting substance.Mined in Virginia,South Africa,Chinia,Australia.Check out www.homeharvest.com for commerical and home garden uses.

Answer 4

It is the rock that is known as "fools gold" or mica and forms in layers like brittle stacks of paper. When it is heated and steamed it puffs like pop corn and falls apart. For agriculture it is sifted and graded and used as a soil amendment or as an inert soil product (component or by itself) or in soil-less mixes.

Answer 5

Vermiculite is a natural mineral that expands with the application of heat. The expansion process is called exfoliation and it is routinely accomplished in purpose-designed commercial furnaces. Vermiculite is formed by hydration of certain basaltic minerals. Large commercial vermiculite mines currently exist in South Africa, China, Brazil, the USA and several other countries.

Structure

Vermiculite is a 2:1 clay, meaning it has 2 tetrahedral sheets for every one octahedral sheet. It is a limited expansion clay with a medium shrink-swell capacity. Vermiculite has a high cation exchange capacity at 100-150 meq/100g. Vermiculite clays are weathered micas in which the K+ ions between the molecular sheets are replaced by Mg2+ and Fe2+ cations.

[edit] Commercial uses

    * moulded shapes, bonded with sodium silicate for use in:

          o high-temperature insulation

          o refractory insulation

          o fireproofing of structural steel and pipes

    * soil conditioner

    * as loose-fill insulation

    * packing material, valued for its high absorbency

    * suitable as a substrate for various animals and/or incubation of eggs

    * lightweight aggregate for plaster, proprietary concrete compounds, firestop mortar and cementitious spray fireproofing

    * as an additive to fireproof wallboard

    * component of the interior fill for firestop pillows, along with graphite

    * carrier for dry handling and slow release of agricultural chemicals

    * soil additive for plants, together with perlite for potted plants

    * growing medium for hydroponics.

    * means to permit slow cooling of hot pieces in glassblowing, lampwork, steelwork, and glass beadmaking

    * used in in-ground swimming pools to provide a smooth pool base

    * used in commercial handwarmers

    * used as a sterile medium for the incubation of reptile eggs

    * light-weight insulative concrete [1]

    * used in AGA cookers as insulation

    * used in explosives storage as a blast mitigant

[edit] Commercial manufacture of exfoliated vermiculite

Vermiculite output in 2005

Vermiculite output in 2005

In 2005, South Africa was the top producer of vermiculite with about 40% world share followed by the USA and China, reports the British Geological Survey.

While some exfoliators focus on only a few of the possible applications, others can provide vermiculite products for all its applications. It is common for vermiculite exfoliators to also exfoliate perlite, as both are often sold together. To set up a new exfoliation process, it is possible to find expert consultants to advise in the design and construction of the desired facilities. Vermiculite exfoliators have an international trade association called The Vermiculite Association to represent the industry's interests and to exchange information.[1] Many of its members also maintain memberships in The Perlite Institute.[2]

[edit] Fireproofing

For many years, since the advent of the asbestos removal business, before which nearly everyone sold asbestos-based spray fireproofing, vendors could be cleanly categorised into users of MMMF (man-made-mineral-fibres), which included both rockwool and ceramic fibres, and cementitious sprays, whereby the binder was typically portland cement and the lightweight aggregate inside the plaster was vermiculite. For many years, makers of the cementitious products would point out the ill health effects that are possible from overexposure and lack of proper industrial hygiene procedures when working with MMMF. Vendors of the MMMF products would point out the possibility of asbestos contamination, particularly with US mined vermiculite ore. Ironically, both sides were defending against lawsuits in the asbestos litigation and eventually stopped pointing out these particular weak spots about one another, which makes sense, since most affected manufacturers are still in receivership as a means of dealing with the results of the asbestos litigation. One large British manufacturer of asbestos products even had to discontinue selling anything to North America directly, having to rely on surrogate trading companies for sales to that continent now.[citation needed]

[edit]

Answer 6

Vermiculite is a naturally occurring product - for the simple version read here -

http://en.wikipedia.org/wiki/Vermiculite

Answer 7

(MgFe,Al)3(Al,Si)4O10(OH)2·4H2O

From wikipedia:http://en.wikipedia.org/wiki/Vermiculite

Vermiculite is a 2:1 clay, meaning it has 2 tetrahedral sheets for every one octahedral sheet. It is a limited expansion clay with a medium shrink-swell capacity. Vermiculite has a high cation exchange capacity at 100-150 meq/100g. Vermiculite clays are weathered micas in which the K+ ions between the molecular sheets are replaced by Mg2+ and Fe2+ cations.