Bentonite, also known as bentonite, is a clay mineral with montmorillonite as the main component, and its chemical composition is quite stable, known as "universal stone".
The properties of bentonite depend on montmorillonite, depending on the content of montmorillonite. Under the condition of water, the crystal structure of montmorillonite is very fine, and this special fine crystal structure determines that it has many excellent properties, such as high dispersion, suspension, bentonability, adhesion, adsorption, cation exchange, etc. Therefore, bentonite is known as "a thousand kinds of minerals", and it is widely used at home and abroad in cat litter, metallurgical pellets, casting, drilling mud, textile printing and dyeing, rubber, papermaking, fertilizer, pesticide, soil improvement, desiccant, cosmetics, toothpaste, cement, ceramic industry, nanomaterials, inorganic chemicals and other fields.
China's bentonite resources are extremely rich, covering 26 provinces and cities, and the reserves are the first in the world. At present, China's bentonite has developed rapidly, and its application has reached 24 fields, with an annual output of more than 3.1 million tons. But there are too many low-grades, and less than 7% of high-grade products. Therefore, the development of high value-added products is a top priority. Vigorously develop high value-added bentonite products can obtain high value-added returns, and avoid waste of resources, at present, bentonite has only 4 categories of high added value, which should be paid attention to.
1. Montmorillonite
Only pure montmorillonite can fully utilize its own excellent properties.
Montmorillonite can be purified from natural bentonite that meets certain conditions, and montmorillonite has been used in high-tech fields such as medicine and feed as an independent variety beyond bentonite.
China's definition of montmorillonite products is not uniform, which often causes ambiguity in montmorillonite products. At present, there are two definitions of montmorillonite products, one is the definition of montmorillonite products in the non-metallic mineral industry: montmorillonite content greater than 80% in clay ore is called montmorillonite, such as montmorillonite desiccant, etc., its product content is mostly qualitatively quantitatively quantified by methods such as blue absorption, and the grade is nothing more than high-purity bentonite; The other is the definition of montmorillonite in the field of scientific research and research, and its product content is mostly qualitatively quantified by XRD and other methods, which is montmorillonite in the true sense, which can meet the requirements of montmorillonite products in medicine, cosmetics, food and other industries. The montmorillonite described in this article is a montmorillonite product at this level.
Montmorillonite can be used in medicine
Montmorillonite (Montmorillonite, Smectite) is included in the United States Pharmacopoeia, British Pharmacopoeia and European Pharmacopoeia, odorless, slightly earthy, non-irritating, no effect on the nervous, respiratory and cardiovascular systems, with good adsorption capacity, cation exchange ability and water absorption and expansion ability, good adsorption effect on Escherichia coli, Vibrio cholerae, Campylobacter jejuni, Staphylococcus aureus and rotavirus and bile salts, and also has a fixed effect on bacterial toxins. Antidiarrheal is rapid, so its preparation is widely used in clinical practice. In addition to preparations, montmorillonite APIs are also used in drug synthesis and as excipients for sustained-release preparations.
Montmorillonite can be used in veterinary medicine and animal health
Montmorillonite is used in animal farming, the product must be purified, must be determined to be non-toxic (arsenic, mercury, lead, ashlenite do not exceed the standard), any direct use of bentonite raw ore for drugs will cause harm to livestock.
Montmorillonite is widely used in animal breeding, and its hot spots are almost all concentrated in intestinal protection and diarrhea, feed mold removal, hemostasis and anti-inflammatory, and fence maintenance.
Montmorillonite can be used in cosmetics
Montmorillonite can effectively remove and absorb the residual makeup, dirt impurities and excess oil in the skin lines, and adsorb excess oil, exfoliate, accelerate the shedding of old dead cells, converge excessive pores, lighten melanocytes, and improve skin tone.
Montmorillonite can be used in crystal shrimp farming, can purify water, will not change the pH value of water, provide mineral nutrients, has a whitening effect on crystal shrimp, and is a necessity for raising crystal shrimp.
Montmorillonite is used as a food additive and emulsifier in food, and can be used as a weight loss food; It can make fruit juice and sugar juice clear and expand; Softens hard water. It can be used as a vegetarian additive, replacing traditional animal-converted additives such as protein and gelatin.
Montmorillonite can be used as a wine clarifier, nano montmorillonite has a huge surface adsorption and interlayer has the characteristics of permanent negative charge, can effectively adsorb proteins, macromolecular pigments and other positively charged colloidal particles and produce agglomeration, can be used for such as wine, fruit wine, fruit juice, soy sauce, vinegar, rice wine and other brewing products clarification and stabilization treatment. Experimental results: nanomontmorillonite does not change the appearance, color, flavor and other characteristics of wine, fruit wine and other beverages, and can be naturally separated by sinking because of its insoluble ratio to water.
Application process: add nano-montmorillonite wine clarifier to 3-6 times the amount of water to fully swell, stir into a slurry, and then add to the wine to be treated and other products stirred and dispersed evenly, and finally filter to obtain a clear and shiny wine body.
Nano montmorillonite wine clarifier has been used for wine clarification for more than 50 years, which is very safe and reliable, and has an auxiliary effect on the prevention and control of "metal ruin" and "browning" of wine.
2. Organic bentonite
Generally speaking, organic bentonite (amination) is obtained by covering sodium-based bentonite with organic amine salts.
Organic bentonite is mainly used in paint ink, oil drilling, polymer active filler and other fields.
Organic bentonite is an effective gelling agent for organic liquids. Adding a considerable amount of organic bentonite to the liquid organic system will greatly affect its rheology, viscosity increases, fluidity changes, and the system becomes thixotropic. Organic bentonite is mainly used in paints, printing inks, lubricants, cosmetics and many other industrial sectors to control viscosity and flowability, making production easier, storage stability and better performance. In epoxy resin, phenolic resin, asphalt and other synthetic resins and Fe, Pb, Zn and other series of pigment paints, it can be used as an anti-settling auxiliary, with the ability to prevent pigment bottom agglomeration, corrosion resistance, thickening coating, etc.; Used in solvent-based inks can be used as thickening additives to adjust the viscosity and consistency of inks, prevent ink diffusion, and improve thixotropy.
Organic bentonite is used in oil drilling and can be used as an oil-based mud and additive to increase the consistency of mud, improve mud dispersion and suspension.
Organic bentonite is used as a filler for rubber and some plastic products such as tires and rubber sheets. Organic bentonite is used as rubber filler, which is a new technology in the eighties and is widely used in the former CIS, the United States, the United Kingdom and other countries. After three years of research and development, the research institute of Jilin Chemical Industry Company has successfully developed the technical method of producing organic bentonite (also known as modified bentonite) for rubber. The products are tried in Huadian , Jilin, Changchun, Jihua and other tire factories, and the effect is remarkable, not only the service life of tires is extended, but also the cost of tire production is greatly reduced. Organic bentonite for rubber (modified bentonite) has been recognized and welcomed by rubber enterprises, and the market potential is huge.
Nanoscale organic bentonite is also used for nano modification of plastics such as nylon, polyester, polyolefin (ethylene, propylene, styrene, vinyl chloride) and epoxy resin to improve its heat resistance, strength, wear resistance, gas barrier and specific gravity. The application of nano-scale organic bentonite in rubber is mainly used for nano-modification of rubber products, improving its air tightness, fixed extension attraction and wear resistance, corrosion resistance, weather resistance and chemical resistance. Polyurethane elastomer/montmorillonite nanocomposites and EPDM/montmorillonite nanocomposites have been well studied.
Nano-scale organic bentonite/polymer masterbatch (modified and easily dispersed blend) can be made from nano-scale organic bentonite/polymer masterbatch (modified and easily dispersed), and nano-scale organic bentonite/polymer masterbatch can be combined with rubber or elastomer to prepare nano-bentonite composite thermoplastic elastomer, which can accelerate the development of nano-thermoplastic elastomer.
3. High white bentonite
High white bentonite is a high-purity sodium (calcium) based bentonite with a whiteness of at least 80 or more. High white bentonite benefits from its whiteness and is popular in many aspects such as daily chemical products, ceramics, papermaking, and coatings.
Daily chemical products: high white bentonite in soap, washing powder, detergent as fabric softener, softener, absorb dissolved impurities, prevent the accumulation of crusts and residue on the surface of the fabric, reduce the deposition of zeolite on the fabric; It can keep dirt and other particles in the fluid medium in suspension; Adsorbs oils and other impurities, and can even condense bacteria. It is used as a gelling agent in toothpaste and cosmetics, and can replace the thickener and thixotropic agent for toothpaste imported from abroad--- synthetic magnesium aluminum silicate. The test results show that the high white bentonite toothpaste with a montmorillonite content of > 97% and a whiteness of 82 is delicate and straight, the tensile viscosity of the paste is 21mm, and the paste has good gloss after filling. After 3 months of continuous placement at a high temperature of 50 degrees, the paste is dissected, the color is unchanged, the toothpaste is basically sticky, there is no granulation and dry mouth, and the aluminum tube is completely non-corrosive, and the surface of the paste is smooth and delicate. After 5 months of high temperature and 7 months of room temperature observation and inspection, toothpaste meets the new standard of toothpaste, and can be used as toothpaste raw materials.
Ceramics: White bentonite is used as a plastic filler in ceramics, especially in products that require high whiteness after sintering. Its rheological and expandable properties give the ceramic paste plasticity and increased strength, while stabilizing the suspension of water in the paste, while its dry adhesion provides a high binding strength and bending resistance to the roasted end product. In ceramic glazes, white bentonite is also used as a plasticizer and thickener, providing strength, plasticity and high adhesion to the glaze and support, favoring ball milling.
- Papermaking: In the paper industry, white bentonite can be used as a multifunctional white mineral filler.
- Coating: viscous regulator and white mineral filler in the coating, which can partially or completely replace titanium dioxide.
- Starch modifier: make storage stability and use performance better.
- In addition, white bentonite can also be used in high-grade adhesives, polymers, paints.
4. Granular clay
Granular clay is made of activated clay as the main raw material by chemical treatment, the appearance is unshaped small granular, it has a higher specific surface area than active clay, has a high adsorption capacity, widely used in petrochemical industry aromatic purification, aviation kerosene refining, mineral oil, animal and vegetable oil, wax and organic liquid decolorization refining, also used in lubricating oil, base oil, diesel and other oil refining, remove residual olefins, gum, asphalt, alkaline nitride and other impurities in the oil.
Granular clay can also be used as a moisture desiccant, internal drug alkali detoxifier, vitamin A, B adsorbent, lubricating oil coincident contact agent, gasoline vapor phase essence preparation, etc., and can also be used as a raw material for medium temperature polymerization catalyst and high temperature polymerization agent.
At present, non-toxic, non-entrainment, small oil absorption, and granular clay that can be used for edible oil decolorization and refining is a hot spot in demand.
Post time: Dec-20-2022