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Sources and
perperties©¦Uses©¦Trend
Sources and perperties
Brucite is hexagonal mineral and native magnesium hydroxide
occurs in serpentines and impure limestone, hardness is
2.5 on Moke scale and specific gravity is 2.38-2.40.
Brucite is a semi-rare mineral, before had not been found
in China on large scale. Since mid 1990's, large deposit
of brucite has been found in China, most commercialy valued
mines are located in Fencheng city(formerly a county of
Dandong). Up to now, over 4 million tons of reserve has
been found in Dandong.
Uses
Brucite is often used as flame retardant filler in plastic
industry and paper-making industry; as additive in chemical
fertilizer; in environmental protection field, magnesium
industry, medical industry ; it is also used as furnace
additive in steel-making industry.
Trend
Recent years the application of brucite develops fast in
many areas, partly because of the emerging of advanced technological
solution. The bright future for brucite may be illustrated
by the following two examples.
1) In converter
steel-making industry
Calcined brucite lump is being introduced to replace caustic
calcined magnesite ball which is currently widely used in
slag splashing converter maintenance. Compared with caustic
calcined magnesite ball, calcined brucite lump has higher
composition of MgO, more suitable fluidity, better reactivity,
it could improve the composition of MgO in slag, lengthen
the serverce life of converter and reduce the frequency
of magnesia brick replacement, thus lower the production
cost, now this technique has been applied successfully by
some steel manufacturers in Japan.
2) In flame retardant
industry
Because of the advantages of mineral fillers(mainly ATH
and Magnesium hydroxide) in terms of smoke generation, toxicity,
and environmental aspects, they will outpace the more traditional
compounds in flame retardant industry.
Although currently ATH is the most important flame retatdant
among mineral fillers, it should be noted that magnesium
hydroxide is the most fastest growing part. Compared with
ATH, Magnesium hydroxide has a lower smoke generation, higher
temperature stability field (up to 340¡æ) than ATH (200¡æ)
, which allows the processing with a wide variety of thermoplastics,
eg. polypropylene or nylons. The recent technological breakthrough
in overcoming some of disadvantages of magnesium hydroxide(e.g.
impurity or high loading") greatly increases its market
potential.
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