Bentonite
مشخصات
Alternative (Trade) Names | Bentonite Mineral, Amargosite, Taylorite |
HS Code | 25081000 |
Physical and Chemical Properties | |
Chemical Formula | (Al2O3-4SiO2-4H2O) |
Appearance | Gray, Cream |
Density | 1 g/cm3 |
PH | 9-10 |
Flammability | Non-flammable |
شرح
Bentonite is a mineral from the clay group and is composed of swollen and crystalline quasi-clay minerals. It generally contains montmorillonite and a small amount of bidellite, and is formed by chemical changes in volcanic ash. In other words Bentonite means clay that has 90-85% of montmorillonite mineral. Bentonite is an adsorbent of aluminum and contains elements such as sodium, calcium, aluminum and potassium. If Bentonite is poured into water, it becomes bulky after mixing. After drying this compound is also stronger than concrete. The most important applications of Bentonite include foundry, earth wells, cosmetics and medicine, oil well drilling, construction and civil engineering, spray production and food additives.
Chemical properties of Bentonite
Bentonite belongs to the family of plate silicates and has a three-layer structure. In its structure, an octagonal aluminum layer is placed between two layers of quadrilateral silica. The quadrilateral plates are made of SiO4, and each quadrilateral is connected to its adjacent quadrilaterals by three oxygen atoms. Bentonite contains hydroxyl (OH) which are located in the center of the hexagonal ring. The quadrilateral plates are connected by octagonal plates. The stem distance in this group is 14 angstroms. This distance can vary from 9.6 to 21.4 angstroms due to the ability of smectite to absorb water molecules.
کاربرد ها
Application of Bentonite in drilling industry
Bentonite ore is used in drilling deep oil and gas wells (3000 to 5000 thousand meters). Bentonite has been used as a drilling mud for many years due to its suspension and swelling power. To do this, Bentonite is mixed with water and injected into drilling wells. This compound covers the wall with a gel form and fills the cracks and crevices of the wall and reduces water. Sodium Bentonite or swollen Bentonites are used in oil and gas drilling. When Bentonite is mixed with water, relatively large shells of Sodium Bentonite are converted into colloidal particles, releasing electrical energy stored in the crystal lattice. These layers then swell about 15 to 30 times their original volume. They then swell about 15 to 30 times their original volume. This causes the Bentonite to cover the well wall and prevent waste on drilling fluids. It also prevents the wall from falling and lubricating and moving the drill smoothly.