Kaolin usages and benefits
Kaolin clay powder Usages:
The most consumed kaolin in fillers, coverage with polishing and bleaching for in the special expander in., wear-resistant, etc., diluents, etc. hard in the petrochemical industries software, A levels and as a catalyst in various industries, etc., paper, ceramics, composite materials and colors, etc. plastic of rubber, Pharma, Inc. fiberglass industries, refractory, etc., building materials, construction, insecticides, etc. catchy, etc. detergents, food, pharmaceuticals, industry, agriculture, and chemical fertilizers.
- Filler and proper coating – remains chemically unchanged.
- As suitable ink and dye absorber.
- As a hardener in the petrochemical industry.
- Having a white color that makes yen usable as a pigment.
- Special polishing and whitening capability.
- Catalytic properties.
- It has excellent filling and coating properties.
- Softening and non-abrasive surface.
- Low ability to conduct electricity and heat.
white kaolin clay
In Iran, this mineral is used in refractory internal coatings of furnaces, heating boilers and tiles. About 50 percent is used in paper making as fillers and coatings (surface coating) – 20 percent in ceramic and refractory industries-10 percent in rubber making as fillers and 20 percent in plastic dyeing.
Composite absorption and coating are the advantages of good and filling uneven surfaces of paper with cellulose paste and creating transparency in paper are the advantages in paper industry.
Pharmaceutical industry:
It is known in the pharmaceutical industry for its combination of it with hydrated aluminum silicate. The mineral is used in the preparation of antidiarrheal drugs, which are taken in an amount of 2 to 6 grams every 4 hours. It is used to prepare pain relievers، to reduce inflammatory pain and treat diseases of the gastrointestinal tract.
Drugs Composite include: syrup, kaolin, pectin, etc., syrup, kaolin children, syrup, morphine, syrup.
Drugs containing this product may be side effects such as sensitivity, excessive to symptoms, drop in blood pressure, urticaria, fever, joint pain, etc., blister, measles, digestive discomfort, etc., nausea, headache, have, and with the discontinuation of the drug disappear.
Pigment:
Kaolin used as a pigment. Particle size and viscosity are divided into fillers and paper coatings. It is an inexpensive mineral filler of white or almost white color, which is neutral in a wide range. Non-abrasive particle size and small but legendary control low thermal and electrical conductivity and good luminance used in rubber and adhesive paint paper plastics.
The chemical composition is important except that it affects the paint and absorbs oil or oil is especially important for paint or rubber. The above properties, along with his viscosity and shape, make it to be used as pigment coating paper. Brilliance-smoothness and compound acceptance in the art of printing and writing paper.
In the Plastics of the cave is used to create a smooth surface-stability in different directions and resistance to chemicals.
Kaolinite
Paper industry:
The use of Kaolin in paper making makes the paper soft and absorbs ink. cheapness and proper coating are other advantages of using kaolin in the paper industry.
This paper is not suitable for use in modern printing even if the gap between the cellulose fibers is filled with mineral filler as long as it has no surface coating. The use of fillers in paper pulp fills some gaps and seams between cellulose fibers, so many fine Composite printing points do not fit properly into these parts.
Surface coating for softness-luminosity and absorption of ink is printed on Bag paper. Proper coating increases the use of paper.
Cavendish quickly disperses in Verde (even in hard Verde) and is thinly coated on paper by modern veneer machines. Coating is suitable for glossy paper light paper and gravure paper is suitable by rolling (offset) method.
In the paper industry is used must be quickly suspended. Particle size and granulation are especially important. The amount of viscosity and the percentage of particles smaller than 2 microns are more important.
First class coating kaolin has 92% of its particles less than 2 microns and a luminosity of at least 87%. Second-class coating kaolin has 80% of its particles less than 2 microns and its luminosity is at least 85.5%.
In summary, the following properties can be considered for kaolin for use in the paper industry:
- transparency: the minimum transparency for using kaolin as a filler is 80% and for Clay as a coating is 85%, which is determined by comparison with the transparency standard.
- particle size: the most accurate method for determining the size and dispersion of particles is based on the Stoke principle, in other words, the sedimentation rate in the fluid is controlled. The particle size is determined from the time the yen settles.
- viscosity: the psychic value of Kaolin is very important in paper coating.
- sieve residue: 325 mesh is used as an abrasive material or sieve residue. The practical method is to grind 100 grams of the sample and mix well, dispersed by chemicals. Then the weight measures the percentage of solids in the mixture. Weighs the total residue on the sieve and calculates the percentage.
Paint industry:
The use of Kaolin in plastic paint helps to control viscosity. Kaolin is used 10% in dyeing and coating power, increases paint lubrication and dispersion. In dyeing, high-quality and pure type is used as dyes and fillers. In washable paints with coarse grained Kaolin in the form of matte and fine-grained kaolin in the form of glass.
The position of the paint industry in the consumption of it has been similar to that of the rubber industry in recent years. The largest growth rate in the paint industry was in Europe, which is estimated at about two percent per year. In general, and near consumption growth rate is expected to be one percent in this industry. Of course, if there was economic growth in the countries as before, that would be 1.5%.
Its consumption in the paint industry in America increased from 228,000 tons in 1991 to 329,000 tons in 1997 and decreased to 268,000 tons in 1998. From where paint production in the United States is about 30% of total global production. So, the consumption of Kaolin in the world paint industry in 1998 amounted to 840 thousand tons.
It is basically used as an expander and the main white material as an alternative to titanium oxide in paint production. Calcined Kaolin is the main that is used in the paint industry. Bright color while opaque is one of the characteristics of Kaolin used in the dyeing industry and resembles used in the paper industry.
The smooth surfaces of it, especially in the paint industry, are overlapped with a special material that makes the paint sheet durable and the life of the it. The greatest demand for this product in the paint industry – is the manufacture of matte interior paints. The U.S. Bureau of standards recommends using at least 20 percent of kaolin for home paints.
It can usually be added up to 10% by weight of glossy paints. Kaolin used in dyeing should be light in color and have a minimum of impurities. It has a high suspension coefficient in water and its soluble salts are low. In terms of luminosity between 80-90% and its particles below 2 microns.
Rubber:
In the rubber industry, kaolin is also used as a filler. It increases wear resistance and Its strength. Pure and soft type is used in soft tires such as rubber tiles and gross kaolin is used in the production of hard tires such as heels, soles, shoes, and automotive tires.
The consumption of it in the rubber industry in 1998 was 1.08 million tons. Between 1990 and 1998 global tire consumption rose from 2.52 million tons in 1991 to 61.6 million in 1998, representing an average annual growth of 3.9% over the 1990s. An annual growth of 1% is forecast for the industry’s near cowheel consumption.
The consumption of Kaolin in the plastics industry reduces the price of rubber. Because Kaolin is much cheaper than natural rubber or elastomer. It is used in the rubber industry and is not of good quality. In the United States used in this industry is concentrated in the air. In industries where coarse particles are disrupted such as rubber industries that extrusion.
Calcined kaolin is also used as a coating in the rubber industry. One of the main characteristics of it used in the rubber industry is that 99.5 percent of the particles must be under 44 microns.
Ceramic Industry:
Kaolin 20% is one of the raw materials in the porcelain ceramic tile industry. Its fireproof aluminum is that the amount of Al2O3 in it depending on the type, it is different. A variety of low-alumina, kaolin Made. Flint (35-45%), and types with high alumina.
The oldest and perhaps the most common method of using this material in the industry is the use of these mineral ores in the manufacture of various ceramic products. Porcelain flowers have been used in the manufacture of ceramics for more than four thousand years. In the ceramic industry, a series of methods of formulation of materials, shaping, heating and baking are used.
Therefore, the range of variations in the type of consumption is wide and in other words, determines the type of product and method of production.
It is used in the ceramic industry due to its special chemical composition. In contrast to heat, the state of the glass does not change and creates a special brightness and transparency in the product. In the preparation of ceramics, the most important factor is the mixing ratio of kaolin, Silica and the melting aid in the ceramic body.
The feature of kaolin used in the ceramic industry generally relates to the harmful impurities contained, which discolor the product after baking. The most important and harmful impurities. Other harmful elements include copper – chromium and manganese.
This problem occurs when these ingredients are finely placed in the clay, which then appears in the form of a product body after baking, and in the event of a decrease in oxygen in the oven in baking biscuits. Holes are formed around the stain. The permissible value is between 0.6 and 0.7 percent.