Non-metallic minerals--properties and classification of kaol
Non-metallic minerals--properties and classification of kaolin
Kaolin is a non-metallic mineral, a kind of clay and clay rock mainly composed of kaolinite clay minerals. Pure kaolin is white, fine, soft soil-like, and has good physical and chemical properties such as plasticity and refractoriness. Kaolin is widely used, mainly in papermaking, ceramics and refractory materials, followed by coatings, rubber fillers, enamel glazes and white cement raw materials, and a small amount is used in plastics, paints, pigments, grinding wheels, pencils, daily cosmetics, soaps, pesticides, medicines, textiles, petroleum, chemicals, building materials, national defense and other industrial sectors. Do you know about the properties and classification of kaolin? Let the editor of Qianjiaxin Refractory Materials introduce it to you!
Kaolin physical and chemical properties:
Properties: Mostly dull, white and delicate when pure, gray, yellow, brown and other colors when containing impurities. The appearance can be loose soil blocks or dense rock blocks depending on the cause.
Density: 2.54-2.60 g/cm3. Melting point: about 1785℃. It has plasticity, wet soil can be molded into various shapes without breaking, and can remain unchanged for a long time.
Kaolin classification:
1. Soil classification The minerals contained in kaolin in nature are mainly divided into clay minerals and non-clay minerals. Clay minerals mainly include kaolinite family minerals and a small amount of montmorillonite, mica and chlorite; non-clay minerals mainly include feldspar, quartz and aluminum hydrates, as well as some iron minerals such as hematite, siderite, limonite, etc., titanium minerals such as rutile, etc. and organic matter such as plant fiber. The main factor that determines the properties of kaolin is clay minerals.
2. Industrial type
According to its texture, plasticity and sand mass fraction, it is divided into three types: 1) Hard kaolin: hard, no plasticity, plasticity after crushing and fine grinding. 2) Soft kaolin: soft, strong plasticity, sand mass fraction <50%; 3. Sandy kaolin: soft, weak plasticity, sand mass fraction >50%.
Processing methods of kaolin:
Kaolin processing methods include mechanical crushing and air flow crushing. Mechanical crushing generally crushes to about 300-1000 mesh, but its crushing process is mechanical, so the iron content and other impurities in the crushed fine powder increase, which is defective for industries with high application purity requirements; air flow crushing adopts mutual collision and shearing between materials, without the participation of crushing media, so it effectively guarantees the purity of the material, thereby meeting the application efficiency of industries with high purity requirements. At the same time, the crushing fineness of the air flow crusher can reach 5000 mesh (the fineness range can be adjusted from 1000 mesh to 5000 mesh).