4A molecular sieve can adsorb low molecular compounds

4A molecular sieve can adsorb low molecular compounds

4A molecular sieve can adsorb low molecular compounds, such as water, methanol, ethanol, hydrogen sulfide, sulfur dioxide, carbon dioxide, ethylene, propylene, etc., and does not adsorb any molecules (including propane) with a diameter greater than 4A. The selective adsorption performance of water is higher than that of any other molecule.
It is one of the molecular sieve varieties commonly used in the industry.
It is possible to evaporate water in a large space of 110°C, but it is impossible to drain the water in the hole.
Therefore, in the laboratory, dehydration can be activated by drying in a muffle furnace at a temperature of 350°C and drying at atmospheric pressure for 8 hours (if there is a vacuum pump, it can be dried for 5 hours at 150°C).
The activated molecular sieve was cooled in air to about 200°C (about 2 minutes) and immediately stored in a desiccator.
If conditions permit, use dry nitrogen for protection during cooling and storage to prevent moisture in the air from being adsorbed.
The old molecular sieve will produce pollutants after being used, and the activation temperature is not only as high as 450°C, but also water vapor or inert gas (nitrogen, etc.) will be introduced to replace other substances.
Avoid oil and liquid water.
Avoid contact with oil and liquid water during use.
 Each oxygen atom in the framework of the 4A molecular sieve is shared by two adjacent tetrahedrons. This structure forms large pockets of crystals that can be occupied by cations and water molecules, and these cations and water molecules have greater mobility.
It can carry out cation exchange and reversible dehydration.
Ion exchange is carried out on a framework containing aluminum ions. Each aluminum ion has a negative charge, which can not only bind sodium ions and other cations.
Calcium ions and magnesium ions can enter the large pores occupied by the original sodium ions, replacing the sodium ions in the 4A molecular sieve-that is, sodium ions can be ion exchanged and can be combined with Ca2 + and Mg2 + ions in hard water.
Exchange achieves the purpose of softening water quality.