Welcome To Iran Bentonite Co. .We Are  a Professional & Established Company. Need Any Help ?




Office Hour: 09:00am - 4:00pm

Casting Bentonite

Home  > Products


Casting Bentonite

Casting bentonite is one of the commercial grades of bentonite with particular properties. Due to the unique qualities of this product as a Molding Bentonite, high-quality castings can be produced using green sand molds with good flowability, compatibility, and thermal stability. Casting bentonite is primarily utilized as a binding substance in molding sand manufacturing to make iron, steel, and non-ferrous castings based on its qualities.

It is vital to bear in mind that we should use a high-quality type of casting bentonite to enjoy all properties of this substance. In this case, Iran bentonite Co. is a reputable bentonite manufacturer and exporter you can rely on. This Iran Casting Chemicals producer provides all interested customers worldwide with superior products of high quality. You can easily count on Iran bentonite Co. for your intended grade, whether it is an Iran Binding Material or a rare grade of bentonite. In addition, you will be satisfied with the logistics options that this casting bentonite manufacturer offers you for a smooth purchase experience.

What Is Bentonite?

Before speaking about specific grades of bentonite that are served as casting chemicals, we need to make a general understanding of bentonites. Bentonite is an absorbent swelling clay made primarily of montmorillonite, a kind of smectite that can either be Na-montmorillonite or Ca-montmorillonite. Compared to Ca-montmorillonite, Na-montmorillonite can swell much more. Bentonite, a clay that swells, may absorb much water, increasing its volume to an eight-fold factor. Because of this, bentonite beds are unsuitable for building and paving roads. However, drilling mud and groundwater sealants take advantage of the swelling property. The mineral montmorillonite/smectite, which is composed of minute platy grains, is an aluminum phyllosilicate and is what makes up bentonite.

Some grades of this useful product are also applied as binding materials in several industries. Any material or substance that holds or attracts other elements to form a cohesive whole mechanically, chemically, through adhesion or cohesion is referred to as a binder or binding agent. Binders, in a more specific sense, are liquid or dough-like materials that, through a chemical or physical process, solidify and bind fibers, filler powder, and other particles that have been added to them. Examples include thickening, adhesive, and glue. Mechanical binders include tie beams in timber construction and binding stones in brickwork.

What Is Casting Bentonite?

Casting bentonite is a type of bentonite clay that acts as a binding agent to prepare molding material for casting iron, steel, and non-ferrous metals. The substance is a white powder with good binding properties, hydrophilicity, expansibility, plasticity, lubricity, and base interchangeability, among other qualities. The pulling strength indexes for casting bentonite under wet pressure, heat, and humidity are high; however, blue absorption power and bentonite value can ensure that “two highs” and uneven phenomena have not occurred. This product has good high-temperature resistance. Molding sand must go through a specific high-temperature condition throughout the casting process. As a result, the bentonite clay’s ability to bind and withstand high temperatures makes it a key indicator for gauging casting bentonite clay.

To create high-quality castings, the unique qualities of bentonite produce green sand molds with good flowability, compactibility, and thermal stability. The capacity for many uses of bentonite is one of the reasons it is utilized as a binding substance. Molds are subjected to a substantial temperature influence during the pouring of liquid metal, often exceeding 1000oC. The bentonite’s suitability for use in foundries is determined by its heat stability, its primary constituent, montmorillonite, and changes in microstructure.

Since bentonite clay has qualities like strong binding, high plasticity, good membrane removal, high air permeability, and stable physical and chemical properties under high-temperature wet conditions, it is employed in casting, mostly in clay-bound sand. The clay wet-type sand is still the most critical modeling material in use today despite the rapid development of various chemical bonded materials. Its broad application range, enormous consumption, and other materials cannot compare. The clay wet-type sand is used as the basis for new contemporary techniques like high-pressure modeling, injecting pressure modeling, air blast modeling, static pressure modeling, and non-shock vacuum pressure adding modeling. The clay wet-type material has an incredibly strong ability to suit modeling conditions.

Different Grades Of Casting Bentonite

The term “bentonite” refers to a form of claystone (a clay rock, not a clay mineral) made primarily of montmorillonite in geology (a clay mineral from the smectite group). Devitrification of volcanic ash or tuff frequently occurs in a marine environment, where it develops. As a result, a very soft, porous rock is produced that may still include crystals of more complex minerals and feels greasy or soapy to the touch. However, the term “bentonite” is broadly used in commercial and industrial applications to describe any swelling clay made primarily of smectite clay particles, including montmorillonite.

Bentonite can be divided into several grades considering multiple factors. Based on the way of producing this clay, it is graded in several groups. The two primary kinds of bentonite, based on this classification, are sodium and calcium bentonite. Although calcium bentonite is more prevalent, sodium bentonite is more valued. Completely devitrified (weathered volcanic glass) ash-fall beds are often also referred to as “K-bentonites” (the pelletized clay rock) in stratigraphy and tephrochronology when illite is the predominant clay species (a non-swelling clay). Illite is a specific kind of non-swelling clay. However, the commercial word bentonite implicitly refers to a swelling clay, smectite, or montmorillonite, making illite more suitable in pure clay mineralogy than “K-bentonite.”

Bentonite also is classified considering its applications in various industries. This approach for grading multipurpose products, such as bentonite, helps companies to find their intended material easily and use it to present a high-quality outcome. For instance, casting bentonite is a material graded based on its primary application as a binding agent. Still, we should remember that even casting bentonite will be classified into various groups based on the purity of each product and the number of ingredients it may include.

Casting Bentonite Production Process

Each grade of bentonites, such as casting, molding, and binding bentonite, must be produced in a particular way to reach the desired outcomes. Still, these production processes share various stages. Mined ore is followed by milling, drying, and, if necessary, sodium activation in bentonite manufacturing. Calcium ions are exchanged for sodium carbonate during sodium activation, transforming calcium bentonite into sodium bentonite.

It is also necessary to know that montmorillonite, which makes up bentonite, is an aluminum phyllosilicate with a low-charge TOT crystal structure. Accordingly, a montmorillonite crystal is built up of layers, each of which is composed of two T sheets joined to either side of an O sheet. The T sheets got their name because they contain four oxygen ions grouped in a tetrahedron around each aluminum or silicon ion. Each aluminum ion in an O sheet is surrounded by six oxygen or hydroxyl ions organized in an octahedron. With a gap of roughly 1 nm between layers, the weak negative electrical charge of the entire TOT layer is balanced by calcium or sodium cations, which bind neighboring layers together. Only a tiny portion of the potential cation sites on the surface of a TOT layer contain calcium or sodium due to the weak negative charge. It is simple for water molecules to penetrate between sheets and fill the empty spaces. It explains why smectite clay minerals like montmorillonite and other smectite clay minerals swell. As a result, bentonites can hold different production processes based on their dominant cation.

Below, We’ll go over a method for processing bentonite clays, which, when dissolved in water, result in very high solution viscosities. In many business applications, grades produced by this process are highly desirable.

The Odds Of This Production Process

Most of Iran’s bentonite manufacturers use alkali or salt treatment as an “activator,” either before or during the initial milling or “working” step. Alkali is never mentioned or depicted as being added at the end of the process, as at the “dry-blend” stage before pulverization. Much-improved sodium bentonite capable of extraordinarily high solution viscosities can be obtained by altering the processing sequence from that previously described. Unexpectedly, the process described in this article yields the purest results compared to the conventional methods used by other manufacturers. The solution viscosity of a solution created with this inverted bentonite treatment consequently increases unexpectedly.

A Summary Of The Process

Our suggested production method calls for the initial working by shearing an untreated 20–50% water slurry of the crude ore. The final product is then dried to a moisture content of between 5 and 15%, preferably between 5 and 10%, and even more preferably between 5 and 6%. Then, “bentonite-activating” metal salt or hydroxide, often Na2C03, is applied to this dried bentonite material. The dry blend is then ground into powder. Although Na2C03 can be helpful with crudes as high as 8% to 10%, it is generally advised to use it in the range of 3 to 5%.

It is also worth mentioning that although the method can be used for both calcium bentonite and combinations of calcium bentonite and sodium bentonite, it is desired to employ a beginning crude that is predominately calcium bentonite.

Casting Bentonite Applications

About half of the bentonite produced in the US as of 1990 was utilized as drilling mud. But as time passed and different grades of this product were introduced to the industry, the applications varied. Nowadays, bentonite is mainly used in the drilling mud, binders, cleaners, absorbents, and carriers of fertilizers and insecticides. Minor petroleum refinement applications include filler, sealant, and catalyst. All in all, we should consider that each grade of this product is intended for a particular application; for instance, fuller’s earth, a name that occasionally refers to calcium bentonite, has applications similar to those of other types of bentonite.

Casting bentonite, as one of the important grades of bentonite, holds its applications. This product’s applications are based on its distinctive properties, among other grades and qualities. Some of its unique characteristics include:

  • With the proper water temperature, it develops good green and dry strength and better flowability.
  • At lower addition, it gains good strength.
  •  It holds excellent thermal stability.
  • Casting bentonite makes it easy to create robust, sharp mold corners.
  • In high-pressure molding, it represents a solid mold strength.
  •  These have superior control over this grade’s active clay.


All these properties make Iran Casting Bentonite a reliable binding material. Below, you can discover this application of our intended grade.

Casting Bentonite As A Binding Agent

Bentonite has long been utilized as a foundry material bond in iron and steel foundries. While calcium bentonite is more frequently used for smaller castings that use “green” or wet molds, sodium bentonite is more regularly used for large castings that use dry molds. Iron ore (taconite) pellets used in the steelmaking industry are made using bentonite as a binding agent. Small amounts of bentonite are a component of commercial and homemade clay bodies and ceramic glazes. It significantly boosts the flexibility of clay bodies and significantly lessens glaze settling, making them much easier to deal with for the majority of applications. It is also worth mentioning that according to the widely recognized notion, bentonite clay hydrates expands, disperses, and then dries to form a bonding film that binds the fine iron ore concentrates together.

Moreover, bentonite’s ionic surface can practically cover sand grains with a sticky coating. Hard sand becomes a moldable aggregate known as “green sand” that can be used to create molds for sand casting when a tiny amount of finely powdered bentonite clay is added and wetted. Such a mixture of clay silt and sand is naturally deposited in several river deltas, providing a superb source of molding sand that was essential to ancient metalworking skills. This stickiness is significantly increased by modern chemical techniques that alter the ionic surface of bentonite, creating amazingly dough-like yet robust casting sand mixtures that withstand molten metal temperatures.

About Iran Bentonite Co’s Product

Iran Bentonite Co. is a reputable bentonite manufacturer that relies on its equipped companies and experienced experts to present you with one of the purest products available. This company’s casting bentonites are cohesive, extensible, and fire resistant. They resist collapse, scab, sand holes, and sand inclusion. Iran binding bentonite, produced by our company, offers the benefits of high strength, high-temperature resistance, high reusability, low adding quantity,  and good sand permeability. These properties help you to enhance casting surface smoothness, ensure casting quality, and increase yield. It is the ideal molding binder for precision casting due to its strong formability, high degree of cavities, simple pouring of the metal solution, and wet and dry model.

When it comes to dealing with Iran Bentonite Co, customers can enjoy a large variety of options. You can connect your experts to have your intended grade if it is Iran Molding Bentonite, Thermal Stable Bentonite, or anything else. Furthermore, consumers are welcome to select their preferred shipping method, too. As usual, our products are packed under universal standards to ensure a safe delivery, but you can go for a particular form of packing.


Casting grade of bentonite clay is a helpful material with high properties, such as solid binding ability, high flexibility, practical membrane removal ability, high air permeability, and consistent physical and chemical characteristics. Each Iran casting bentonite manufacturer may use a different method to produce this material because of various ways of making bentonite. This product is applied in the industry due to its multiple properties, often in clay-bonded sand when casting. If you consider using this substance as a binding agent, please remember that you can rely on Iran Bentonite Co. as a manufacturer and exporter.