Introduction
Bentonite is a valuable and useful clay found abundantly on Earth's surface. This unique mineral is often formed by the weathering and alteration of volcanic ash in the presence of water. Bentonite has a long history; in the past, people used this natural clay to degrease sheep's wool, thicken grape juice, and even as a "bathing clay" in bathrooms. But today, with the advancement of mineral science and chemistry, this mineral has found amazing uses in parent industries; from the steel, oil, and petrochemical industries to oil refining, well drilling, livestock and poultry feed, and medicine.
Types of bentonite in nature and their atomic structure
Bentonites are classified based on the dominant metallic element in their atomic structure (such as sodium, potassium, aluminum, or calcium). Among them, the two types, sodium bentonite and calcium bentonite, have the most industrial applications:
- Sodium bentonite: It has very high swelling (water absorption) properties.
- Calcium bentonite: has less swelling capacity but is equipped with excellent fat absorption properties that provide a substrate for the activation process.
History of the discovery and introduction of the Qara Naz and Kaltke bentonite mines
Valiasr Stone Mining Company is the official discoverer and operator of the rich bentonite mines of Qara Naz and Kaltke, which are located on the Zanjan-Dandi road.
In the years 1369 to 1372, when these mines were discovered and their exploitation license was obtained, its exact industrial uses were unknown. Until the investigation and experiments of Mr. Moniri (manager of Kaveh Tar Company and one of the founders of the oil refining industry in the Middle East), the unique properties of this soil were discovered. After that, the bentonite from these mines entered the industrial production phase, was micronized and packaged, and paved the way for industrial oil refining in the country. This product became known in the market as "decolorizing soil" due to its extraordinary decolorizing properties.
Why is Qara Naz Bentonite from Zanjan unrivaled in the Middle East?
The Gharanaz bentonite mine is located 134 kilometers from the Zanjan-Dandi road, adjacent to the famous Angouran lead and zinc mine. Over the past 30 years, competitors have made many attempts in this area, but the company's bentonite has outdone all competitors for two structural reasons:
- Very high levels of Montmorillonite: This mineral is the main factor in the quality and absorption power of bentonite, which is found in abundance in Qara Naz soil.
- Sustainable million-ton reserve: This huge reserve ensures an uninterrupted and long-term supply of bleaching earth for the country and surrounding export markets.
We have recently established a specialized chemistry laboratory at the company’s headquarters in Zanjan. Repeated oil tests have been conducted on samples extracted from the wells of both mines (samples are available on the site). According to numerous consumers, the bleaching earth produced from the Gharanaz mine is not only unique in the Middle East, but is also considered one of the most superior raw bentonites in the world.
Dye quality testing in the company's chemistry laboratory
What does the process of activating bentonite mean?
Bentonite activation is a significant increase in the mineral soil's ability to absorb impurities, dyes, and harmful oil substances. Scientifically, in the activation (acidification) process, hydrogen ions replace aluminum, iron, and magnesium ions in the soil's crystal lattice. This process is entirely dependent on the underlying soil type and the precise pH adjustment.
Application in the food and feed industries
Bentonite extracted from the mines of Valiasr Company is one of the best options for activation. For example, Kani Saz Jam Company, which is one of the largest and most reputable activated soil production complexes in Iran, is a popular customer of bentonite produced by Valiasr Company. This complex annually purchases, micronizes and activates a significant amount of our bentonite and uses it in the food and purification industries.
Chemical analysis of bentonite
The quality assurance of our bentonite is its specialized analysis sheet that shows the stability of the desired elements in it. In the image below you can see the details of the analysis of this soil:
