What Is Celite?
Celite is a porous solid made by calcining siliceous soil with sodium carbonate.
It is positioned as a type of siliceous soil, and some products are sold under the brand name Celite® as siliceous soil itself. Its main constituent is silicon oxide, and it also contains aluminum oxide, iron oxide, aluminum oxide, and magnesium oxide.
Uses of Celite
Celite’s raw material, siliceous soil, is a fossil of silicea, one of the phytoplankton. The fossilized phytoplankton has microscopic holes in it, which Celite uses for filtration.
1. Industrial Applications
Even highly viscous materials such as fruit juices, pharmaceuticals, gelatin, wastewater, and oil can be filtered relatively stably for long periods of time. In industrial applications, the most commonly used method is to mix the filter media with Celite water and pre-coat it with a thickness of approximately 2 mm between filter papers to maintain the filtration speed.
2.Laboratory Applications
Laboratory applications are also used for filtration of specimens that are too clogged with filter paper. substances are filtered at different rates.
Characteristics of Celite
Celite is made from fossilized algae (phytoplankton) called cassiterite, which grew on the earth tens of thousands to tens of millions of years ago. Algae still grow in the oceans, rivers, and lakes of the world today.
Like seaweeds, they are generally members of the algae family. The term “siliceous algae” is used especially for those with a glassy shell around their cells. Siliceans are single-celled photosynthetic organisms that grow everywhere on earth. in size and take in silica from the water, creating numerous 0.1 to 1.0 micrometer pores that lead inside and out.
Then, when the siliceous dies and settles in large quantities and becomes a fossil, it becomes siliceous soil, leaving only its silica remains. When sodium carbonate is added to this siliceous soil and calcined, it becomes Celite.
Types of Celite
Celite is divided into several types depending on its filtration performance. The grade commonly referred to as silica clay, is also marketed under the name Celite®, and is used for liquids with smooth filtration.
Grades used for difficult-to-filtrate liquids, gels, and colloids are 503, 535, and 545 in Japan. Generally, 535 and 545 are widely used.
1. Celite No. 503
- Particle size : 12 to 20 micrometers
- Flow rate ratio : approx.900
- 150 mesh residual : 9%.
- Applications : Used for liquids that are relatively difficult to filter.
2. Celite No. 535
- Particle size : 20 to 30 micrometers
- Flow rate ratio : approx. 1,350
- Residual at 150 mesh: 9%.
- Applications : Used for beer, fruit juices, agar, antibiotics, enzymes, polymers, alginic acid, crude sugar, alkali solutions, animal oils, glycerin, sugar solutions, treated water, etc.
3. Celite No. 545
- Particle size : 25 to 40 micrometers
- Flow rate ratio : approx. 2,160
- Residual at 150 mesh : 12%.
- Applications : Used for raw materials with high viscosity and especially large amount of foreign matter, such as creams, pectin, mineral oil, agar, pine resin, latex, tar, catalysts, etc.
Other Information on Celite
1. Legal Regulations on Celite
CAS No. 68855-54-9 is added as silica soil.
2. Principle of Celite Filtration
Filtration is the process of removing foreign matter through a filter medium with small holes. In the case of filter paper, substances are easily adsorbed by the cellulose and get trapped, gradually clogging the filter. Silicon dioxide, the main component of Celite, is less likely to adsorb substances.
When Celite is laid on top of the filter paper, substances are prevented from adsorbing and clogging the filter paper, and the fine particles that cause the filter paper to clog are trapped by Celite, resulting in smooth filtration and time savings. , the filtration speed can be increased again by scraping the surface.