Preparation Process And Application Of Wollastonite Powder

2022-12-07

Wollastonite is a chain metasilicate mineral, the main component is CaSi3O9, fibrous, needle-like, non-toxic, chemical corrosion resistance, good thermal stability and dimensional stability, glass and pearl luster, low water absorption It is widely used in industries such as ceramics, rubber, plastics, metallurgy, coatings, paints and building materials, etc., with high market value and has become an important product with huge demand in the application market and broad development prospects. Basic non-metallic ore. Shanghai ZENITH is a manufacturer of wollastonite powder grinding equipment.Today, I will introduce the application trend of wollastonite powder to you.

With the development of powder technology, synthesis technology and surface modification technology, the application fields of wollastonite powder are constantly expanding and deepening, mainly used in plastics, rubber, polymers, coatings, dyes, ceramics, metallurgy, building materials, Environmental protection and asbestos substitutes, etc. China’s wollastonite plays an important role in the world market and has occupied two-thirds of the European casting powder market, but the preparation technology of wollastonite needle-like ultrafine powder with high aspect ratio lags behind developed countries.

Preparation Process Of Wollastonite Powder

Mechanical Crushing

Mechanical pulverization can be divided into dry method and wet method according to different environmental media. The wet microwave pulverization is better for protecting fiber aspect ratio, single fiber fineness and primary relaxation; the dry method consumes more energy but the powder The problem of agglomeration is not as prominent as the wet method, so it is also an effective way.

Chemical Precipitation

The preparation of wollastonite by chemical precipitation method is to use soluble salts containing silicon and calcium, dissolve them in water, and generate calcium silicate through chemical reaction.

Hydrothermal

The hydrothermal method refers to a method in which coal is dissolved in water or other solvents under a certain temperature and pressure in a closed container. Hydrothermal synthesis is an important method for preparing special structural and functional materials.

Application Of Wollastonite

The apparent consumption structure of wollastonite is closely related to the market structure of wollastonite products. The apparent consumption structure of wollastonite in China is as follows: it is used for ceramics, accounting for about 47%; it is used for metallurgical mold slag and welding electrodes, accounting for about 30%; it is used for coating plastics, etc., accounting for about 20%; new composite materials, electronics, etc. Emerging fields such as components and packaging materials accounted for a small proportion, accounting for about 3%. In recent years, domestic backbone wollastonite enterprises have expanded their application fields, accelerated the extension of the industrial chain, and gradually entered the downstream wollastonite finished product industry while improving their production levels. Wollastonite is increasingly closely related to energy-saving and environmental protection, electronic information, biology, aerospace, military industry, and high-tech industries based on new materials and new energy.

In terms of concrete, fiber reinforcement has major advantages in improving the poor tensile properties and ductility of concrete. Research in this direction has developed rapidly in recent years. Among them, the glass fiber reinforced concrete market is developing most rapidly. It is estimated that the total market value will reach 3.3 billion US dollars in 2023.

Silicon fiber has a structure similar to that of glass fiber short fiber, and has certain advantages in replacing glass fiber in the application of glass fiber reinforced concrete. In addition, silicon fiber reinforced concrete has been widely used in dam repair and other application fields abroad. Such as Korean market for dam repair

In terms of coatings, wollastonite can be used as an extender pigment and a substitute for some white pigments in coatings. In addition, according to the characteristics of wollastonite itself, it can also be used as a coating modification additive to expand the functionality of the material. For example, wollastonite has good corrosion resistance and can be used in the field of anti-corrosion coatings. Therefore, relying on wollastonite products to develop functional coatings is one of the important development directions for future applications.

The addition of wollastonite for coatings is about 20%. At present, anti-corrosion coatings for marine engineering are mainly used in anti-corrosion coatings for fan blades, fan brackets, photovoltaic brackets, and cable surfaces. The annual demand for anti-corrosion coatings for marine energy projects covers an area of 4 million square meters, with a total demand of 100,000 tons of coatings. The estimated annual demand for wollastonite is 20,000 tons.

In the papermaking industry, wollastonite powder can be used as filler and plant fiber to be combined into papermaking composite fiber to replace part of plant fiber. Reduce the amount of wood pulp, reduce the cost, improve the performance of paper products, improve the smoothness and opacity of paper products, improve the evenness of paper products, eliminate the static electricity of paper products, reduce the shrinkage rate of paper products, good printability, and reduce plant Pollutant emissions during fiber pulping.