How to choose and use molecular sieve?

Many customers call us to ask us how to decide which molecular sieve to choose as a desiccant in the industry. In response to the questions of our friends, we will sort out the knowledge for everyone. As a desiccant, molecular sieve has zeolite molecular sieve and carbon molecular sieve. Zeolite molecular sieve has two natural Zeolites and synthetic zeolites. Different molecular sieves have different compositions and uses. Zeolite molecular sieves and carbon molecular sieves have their own characteristics. The comparison is as follows:

First, the chemical composition is different. Zeolite molecular sieves are hydrates of crystalline aluminosilicate metal salts. The material of zeolite molecular sieve is natural zeolite and synthetic zeolite. Carbon molecular sieve is an excellent non-polar carbon material, carbon molecular sieve. The raw materials are coconut shell, coal, resin and so on.

Molecular sieves have different sizes. Zeolite molecular sieve crystals have pores of a certain size, and many pores of the same diameter (also called "windows") are connected between the pores. According to their pore or channel system, they can be divided into three groups: small-pore, meso-pore (medium-pore) and double-pore zeolites. Carbon molecular sieves contain many pores of 4 angstroms. When making carbon molecular sieves, according to the size of the molecules, the pore distribution inside the carbon molecular sieve should be 0.28-0.38 nm.

The adsorption principle of zeolite molecular sieve and carbon molecular sieve is different. Zeolite molecular sieve pores have a cleaning function, and the pore size distribution of molecular sieves is very uniform. Molecular sieves selectively adsorb molecules according to the size of the pores inside the crystal, that is, adsorb certain macromolecules and exclude molecules of larger substances. Carbon molecular sieves contain many micropores, which allow molecules with small kinetic scales to diffuse into the pores rapidly, while restricting the entry of large-diameter molecules. Due to the differences in the relative diffusion rates of gas molecules of different scales, the components of gas mixtures can be efficiently separated.

Different uses of molecular sieves. It can be used for pressure swing adsorption separation of oxygen-enriched air. Carbon molecular sieves are widely used in coal fields, petroleum, chemicals, metal heat treatment, electronic manufacturing, food preservation and other industries, while zeolite molecular sieves can be used in addition to petroleum, chemical, natural gas, electronic production, industrial gas separation, pharmaceutical industry, Refrigeration industry, in the field of insulating glass production. By comparing zeolite molecular sieves and carbon molecular sieves, the difference between the two molecular sieves can be clearly understood, and it is easy to judge which molecular sieve to choose as a desiccant in industry. For more knowledge about molecular sieve desiccant, you can communicate with us more.