Sepiolite is a kind of mineral with fiber form, which is a fiber structure extending alternately from the polyhedral pore wall and pore channel. The fiber structure contains layered structure, which is composed of two layers of Si-O-Si bond connected silicon oxide tetrahedron and octahedron containing magnesium oxide in the middle, forming 0.36 nm × 1.06nm honeycomb pore. Sepiolite industrial application usually requires sepiolite grinding mill powder to be ground into sepiolite powder. HCMilling(Guilin Hongcheng) is a professional manufacturer of sepiolite grinding mill. The whole set of equipment of our sepiolite grinding mill production line has been widely used in the market. Welcome to learn more online. The following is an introduction to the use of sepiolite powder:
1. Properties of sepiolite
(1) Adsorption properties of sepiolite
Sepiolite is a three-dimensional special structure with large specific surface area and layered porosity, which is grafted by SiO2 tetrahedron and Mg-O octahedron. There are also many acidic [SiO4] alkaline [MgO6] centers on its surface, so sepiolite has strong adsorption performance.
Sepiolite crystal structure has three different adsorption active center sites:
The first is O atom in Si-O tetrahedron;
The second is water molecules which coordinate with Mg2+at the edge of Mg-O octahedron, mainly forming hydrogen bonds with other substances;
The third is the Si OH bond combination, which is generated by the breaking of the silicon oxygen bond in the SiO2 tetrahedron and receives a proton or hydrocarbon molecule to compensate for the missing potential. The Si OH bond in sepiolite can interact with the molecules adsorbed on its surface to strengthen the adsorption, and can form covalent bonds with certain organic substances.
(2) Thermal stability of sepiolite
Sepiolite is an inorganic clay material with stable high temperature resistance. During the gradual heating process from low temperature to high temperature, the crystal structure of sepiolite has gone through four weight loss stages:
When the external temperature reaches about 100 ℃, the water molecules that sepiolite will lose in the first stage are zeolite water in the pores, and the loss of this part of water molecules reaches about 11% of the total weight of sepiolite.
When the external temperature reaches 130 ℃ to 300 ℃, sepiolite in the second stage will lose the first part of coordination water with Mg2+, which is about 3% of its mass.
When the external temperature reaches 300 ℃ to 500 ℃, sepiolite in the third stage will lose the second part of coordination water with Mg2+.
When the external temperature reaches above 500 ℃, the structural water (- OH) combined with octahedron inside will be lost in the fourth stage. The fiber structure of sepiolite in this stage has been completely destroyed, so the process is irreversible.
(3) Corrosion resistance of sepiolite
Sepiolite naturally has good acid and alkali resistance. When it is in the medium with solution pH value<3 or>10, the internal structure of sepiolite will be corroded. When it is between 3-10, sepiolite shows strong stability. It shows that sepiolite has strong acid and alkali resistance, which is an important reason why sepiolite is used as an inorganic core to prepare Maya like blue pigment.
(4) Catalytic properties of sepiolite
Sepiolite is a cheap and quite practical catalyst carrier. The main reason is that sepiolite can obtain a higher specific surface area and its own layered porous structure after acid modification, which are favorable conditions for the use of sepiolite as catalyst carrier. Sepiolite can be used as a carrier to form a photocatalyst with excellent catalytic performance with TiO2, which is widely used in hydrogenation, oxidation, denitrification, desulfurization, etc.
(5) Ion exchange of sepiolite
The ion exchange method uses other metal cations with stronger polarization to replace Mg2+at the end of octahedron in sepiolite structure, thus changing its layer spacing and surface acidity, and enhancing the adsorption performance of sepiolite. The metal ions of sepiolite are dominated by magnesium ions, with a small amount of aluminum ions and a small amount of other cations. The special composition and structure of sepiolite make it easy for cations in its structure to exchange with other cations.
(6) Rheological properties of sepiolite
Sepiolite itself is a slender rod shape, but most of them are piled up into bundles with irregular order. When sepiolite is dissolved in water or other polar solvents, these bundles will quickly disperse and intermingle disorderly to form a complex fiber network with irregular solvent retention. These network forms form a suspension with strong rheology and high viscosity, showing the unique rheological properties of sepiolite.
In addition, sepiolite also has the characteristics of insulation, decolorization, flame retardancy and expansibility, which has great application value in industrial field.
2. Main Applications of Sepiolite powder process by Sepiolite grinding mill
With the rapid development of China’s economy, the market demand for environment-friendly, high value-added materials is growing. Sepiolite is a kind of inorganic material with good stability due to its special crystal structure, which is pollution-free, environment-friendly and cheap. After being processed by sepiolite grinding machine, it can be widely used in various industrial fields, such as architecture, ceramic technology, catalyst preparation, pigment synthesis, petroleum refining, environmental protection, plastics, etc., which has a huge impact on China’s industrial development. At the same time, people have begun to pay more attention to the innovative application and technology development of sepiolite, and accelerate the construction of a sophisticated sepiolite industry chain to solve the current shortage of sepiolite in the market Low added value of products.
Post time: Dec-28-2022