Molecular sieves bubble when they meet water. Do you know the principle?

The principle of molecular sieves bubbling when they meet water is that molecular sieves are a crystalline material with a porous structure. When water molecules enter these pores,a series of physical and chemical changes will be triggered, resulting in bubbling.

Molecular sieves are a kind of microporous crystals of aluminosilicates, and their internal structure is formed by silicon-oxygen tetrahedrons and aluminum-oxygen tetrahedrons connected by oxygen bridge bonds. The size of these pores is usuallyat the nanometer level, which can selectively adsorb, separate and catalyze molecules. When water molecules enter the pores of molecular sieves, they will occupy the space in the pores, resulting in an increase in the pressure in the pores. As the amount of water increases, the pressure in the pores gradually increases, and eventually the water is released in the form of water vapor, forming a bubbling phenomenon.

In addition, there may be some chemicals in the pores of molecular sieves. When water enters, these chemicals may react with water to produce gas, further exacerbating the bubbling phenomenon. ‌ This phenomenon has certain practical significance in the application ofmolecular sieves. For example, in catalytic reactions, the reaction progress and the activity of the catalyst can be judged by observing the bubbling situation. ‌