Phlogopite is a kind of muscovite mineral. It is mainly produced in contact metamorphic zones and ultrabasic rocks. It contains iron, magnesium and potassium. An aluminosilicate. The aggregates are in the form of flakes, plates or scales. It is widely used in fire protection, pearlescent pigments, building materials, papermaking, rubber and other chemical industries. It is an important mineral raw material. Phlogopite is divided into dark phlogopite (various shades of brown or green, etc.) and light phlogopite (various shades of light yellow). China’s mica minerals are unevenly distributed. Although they are distributed in 20 provinces, municipalities, and autonomous regions across the country, most of them are concentrated in Xinjiang, Sichuan, and Inner Mongolia.
【Basic overview】
Chinese name: Phlogopite
English name: Phlogopite
Category: Layered silicate minerals
Molecular formula: KMg3[AlSi3O10](OH,F)2
Figure 1 shows phlogopite
【Physical properties】[2]
Color: often yellowish brown or reddish brown, sometimes grayish green
Luster: glass luster, cleavage surface is pearl luster
Transparency: 0——25.5%
Crystal system: monoclinic system a=5.3À, b=phenylboric acid 9.2À, c=10.3À, β=100°
Cleavage: Parallel cleavage {001}, extremely complete
Hardness: 2.5
Mineral density: 2.7——2.85g/cm3
Proportion: 2.70—2.85
Morphology: The crystal form is pseudo-hexagonal plate-shaped and short columnar
Whiteness: 60——70
Refractive index: 1.6——1.55
Elastic coefficient: 1394.5-1874 (10 6Pa)
【Chemical Properties】
Phlogopite can be decomposed in boiling sulfuric acid and produce a milky solution, while muscovite cannot; phlogopite can be corroded by concentrated sulfuric acid and can be decomposed in concentrated sulfuric acid and produce a milky solution.
[Identification Characteristics][2]
Phlogopite includes artificial phlogopite (synthetic phlogopite) and natural phlogopite. Natural phlogopite includes dark phlogopite and light-colored phlogopite. Phlogopite is characterized by its complete cleavage of mica, yellow-brown color and gold-like reflection. The difference between it and muscovite is that it can be decomposed in boiling sulfuric acid and produce a milky solution, while muscovite cannot. The general characteristics of phlogopite are the same as those of muscovite, and it is mainly distinguished from other mica by its brown and light golden color. A way to identify biotite that is similar in color is that it is lighter in color than biotite. Peel the two into very thin slices and compare them on white paper. Phlogopite is light yellow-brown, while biotite is gray-green or smoke-colored. The exact identification of colorless or other colored phlogopite requires the help of a microscope.
[Main applications][2-4]
Insulation material Phlogopite is an aluminosilicate containing iron, magnesium and potassium. When its purity is particularly high and its iron content is very low, it will have good insulation properties of pyridine methylamine. , used as insulation materials for electrical equipment and electrical equipment.
Pearlescent pigments Mica-based pearlescent pigments are new materials formed by using mica flakes as the base material and using a special production process to continuously coat one layer or alternately coat multiple layers of high-refractive index metal oxides. Mica pearlescent pigments have excellent properties of non-toxic, light-resistant and heat-resistant, stable chemical properties, wide color spectrum, strong tinting power, strong luminosity and metallic effect, high mechanical strength and other optical properties. They are widely used in decorative coatings for luxury cars and leather. , printing ink, ceramics, military equipment camouflage, coatings, plastics, cosmetics and other fields.
Catalytic performance Due to the strong surface Brownian acidity of the polymer/phlogopite nanocomposite, it has high activity in proton catalytic reactions. Studies have shown that the types of clay minerals have high catalytic properties for intercalation products (especially for proton-catalyzed reactions).
Heat-resistant material Due to its excellent thermal insulation properties, it is used as an important heat-resistant material in industrial production. It can be used to make heat-resistant materials for steam boilers, smelting furnace windows, searchlights and other machinery. part.
【Main References】
1. Zhang Qianwei et al. Experimental study on recovery of phlogopite from molybdenum beneficiation tailings[J]. Nonmetallic Minerals, 2013, 36(2):72.
2. https://baike.baidu.com/link?url=4G-2o-ONEic0i4gz9_J8p2E9DLENdhvd4vrCf5-80TwB0MtEWKg4xOGrBG9owNKNEIyvhinpoLqOIeCvZwzq_PVWuzCuqS6y5kTRuD0IrpfWNTaXxIYXS059sEyfkX kr
3. Sun Guixian et al. Preparation and performance study of phlogopite-iron oxide pearlescent pigment[J]. Nonmetallic Minerals, 2012, 35(3):52.
4. Jiang Shu. Preparation and characterization of epoxy resin/phlogopite nanocomposites[M]. China University of Geosciences (Beijing), Master’s thesis, 2006.
