High active metakaolin for concrete cement mud

[concept of metakaolin] 

metakaolin is a high reactivity meta Kaolin mineral admixture. It is amorphous aluminum silicate formed by calcining ultra-fine kaolin at low temperature. It has high pozzolanic activity and the ability to react with acid and alkali at room temperature and pressure.

[use of metakaolin] 

high performance concrete mineral admixture, white (color) cement mineral admixture, thermal insulation mortar and waterproof mortar mineral admixture, refractory additive, can also be used in the production of geopolymer coating, artificial marble, synthetic molecular sieve, and can be used as medical rubber filler, cable filler, paint filler, etc.

[function of metakaolin]

① Adding metakaolin into concrete and cement products can significantly improve the early strength and 28 day strength.

② Metakaolin can absorb calcium hydroxide in concrete and cement products and inhibit alkali aggregate reaction.

③ Metakaolin can absorb calcium hydroxide in concrete and cement products to prepare pan alkali.

④ Metakaolin can reduce self shrinkage and improve stability.

⑤ Metakaolin can improve the compactness of cement and concrete products, and improve the impermeability, chloride ion corrosion resistance and sulfate corrosion resistance.

⑥ Metakaolin can significantly improve the suspension, stability and stone rate of slurry.

[action principle]

The main components of metakaolin products are highly active aluminum oxide (Al2O3) and silicon dioxide (SiO2). They can react with calcium hydroxide (Ca (OH) 2) produced during cement hydration at normal temperature and pressure to produce cement stone (hydrated calcium silicate and hydrated calcium aluminate) - that is, they can convert white ash into cement. The fineness of metakaolin is 1250 mesh (large particle size 10) μ m) , with good filling effect. Due to the above characteristics of metakaolin, it has the following effects in mortar:

① Cement paste has higher strength than calcium hydroxide (Ca (OH) 2), so metakaolin can improve the strength of mortar.

② Metakaolin is finer than cement and has remarkable filling property, which improves the compactness and impermeability of mortar; Calcium hydroxide (Ca (OH) 2) dissolves in water and forms a water passage after dissolution, while the cement stone transformed by calcium hydroxide is insoluble in water, the water passage disappears and the impermeability is further improved.

③ Because the mortar added with metakaolin is more dense and has higher strength, calcium hydroxide decreases or disappears, alkali aggregate reaction decreases or disappears, and the self shrinkage of the mortar is weakened, which improves the frost resistance, carbonation resistance, sulfate corrosion resistance, chloride ion corrosion resistance, permeability resistance and durability of the mortar.

④ Calcium hydroxide (Ca (OH) 2) is replaced by cement stone to reduce the alkali content in mortar, and pan alkali is prepared.

[comparison of properties of metakaolin and silica fume]

① The pozzolanic activity of metakaolin is higher than that of silica fume. The pozzolanic activity of our metakaolin reaches or slightly exceeds grade I silica fume.

② Metakaolin is convenient for storage and transportation. Silica fume has a large fineness (about 6000 ~ 10000 mesh), which is difficult to store and transport. Metakaolin has a reasonable fineness (1250 mesh), and each bag is packed with 25kg, which is more convenient for transportation and storage than silica fume.

③ The quality of metakaolin products is stable. Silica fume is a by-product recovered from the chimney when producing ferrosilicon and other products. The output of each enterprise is limited, and there are large differences between silica fume produced by different production lines of each enterprise. Therefore, the quality of silica fume is not stable enough, while kaolin is produced by special enterprises, and the product quality is stable.

④ The supply capacity of metakaolin products is stronger. Large scale projects require a large amount of concrete and highly active mineral admixtures. Silica fume is a by-product, and its supply is affected to a certain extent. Partial kaolin is produced by * * * factory, and the output can be expanded according to needs, with quantity assurance.

⑤ Metakaolin is safer for human body. Silica fume inhalation is easy to cause silicosis. Heavy metals in silica fume may cause cancer, but metakaolin doesnt.

Any question pls contact us: info@mcreagents.com