Is molecular sieve a zeolite?
55A molecular sieve is an alkali alumino-silicate (Zeolite) material containing tiny pores of a precise and uniform size which is used as an adsorbent for gases and liquids.
What is the difference between molecular sieve and zeolite?
With different characteristics, zeolite has a glass-like luster and can re-absorb water or other liquids. Molecular sieves have the advantages of high adsorption capacity and strong thermal stability that other adsorbents do not have.
How do zeolites act as molecular sieves?
Upon heating, the zeolites lose their water content with little or no change in their crystal structure. The dehydrated zeolite can reversibly absorb water or other molecules that are small enough to pass through the channels or pores.
Why are zeolites called molecular sieves?
Zeolites are microporous, three-dimensional crystalline solids of aluminium silicate. Zeolites have small openings of fixed size in them which allow small molecules to pass through them easily but larger molecules cannot pass through them; that is why they are sometimes called molecular sieves.
What is the difference between molecular sieve and silica gel?
The key difference between molecular sieve and silica gel is that a molecular sieve is a material containing pores of similar size, whereas silica gel is a substance can be used to prepare a porous material with pores of different sizes.
What is meant by molecular sieve?
Definition of molecular sieve : a crystalline substance (such as a zeolite) characterized by uniformly sized pores of molecular dimension that can adsorb small molecules and is used especially in separations.
How does zeolite trap nitrogen?
Due to the large microporous surface area inside the zeolite adsorbents, the portable oxygen concentrator using the PSA technique can adsorb nitrogen from air and output an enriched oxygen stream under high-pressure conditions.
What zeolite is used for?
There are three main uses of zeolites in industry: catalysis, gas separation and ion exchange. Catalysis: Zeolites are extremely useful as catalysts for several important reactions involving organic molecules. The most important are cracking, isomerisation and hydrocarbon synthesis.
What is zeolite made of?
A zeolite is a hydrated aluminosilicate mineral with a structure characterized by a framework of linked tetrahedra, each consisting of four oxygen atoms surrounding a silicon or aluminum cation.