Differences in the application fields of A-type molecular sieve industry

Molecular sieves, as a type of environmentally friendly material, can be divided into multiple types. Today, the editor will talk about one of the sodium type – A-type molecular sieves. Let’s take a brief look together.

A-type molecular sieves are divided into three types: 3A molecular sieve, 4A molecular sieve, and 5A molecular sieve.

3A molecular sieve is an alkali metal aluminosilicate with a pore size of about 0.3 nanometers. It is mainly used for adsorbing water and does not adsorb any molecules with a diameter greater than 0.3 nanometers. Sometimes, it is also referred to as 3A zeolite molecular sieve; The 4A molecular sieve has a pore size of about 0.4 nanometers and adsorbs water, methanol, ethanol, hydrogen sulfide, sulfur dioxide, carbon dioxide, ethylene, and propylene. It does not adsorb any molecules with a diameter greater than 0.4 nanometers (including propane) and has higher selective adsorption performance for water than any other molecule; 5A molecular sieve can adsorb any molecule smaller than this pore size, generally referred to as calcium molecular sieve. In addition to the functions of 3A and 4A molecular sieves, it can also adsorb C3 to C4 n-alkanes, chloroethane, bromoethane, butanol, etc. It can be used for the separation of isomers, pressure swing adsorption separation, and co adsorption of water and carbon dioxide.

Application characteristics of 3A molecular sieve, 4A molecular sieve, and 5A molecular sieve: Molecular sieve has fast adsorption speed, regeneration times, crush strength, and anti pollution ability, which improves the utilization efficiency of molecular sieve and extends its service life.

Explain the differences between 3A/4A/5A molecular sieves used in the industry:

3A molecular sieve is primarily used for drying petroleum cracking gas, olefins, refinery gas, and oilfield gas, as well as desiccants in industries such as chemical, pharmaceutical, and insulating glass. Mainly used for liquid (such as ethanol) drying, hollow glass air drying, nitrogen hydrogen mixed gas drying, refrigerant drying, etc.

4A molecular sieve is primarily used for drying natural gas and various chemical gases and liquids, refrigerants, drugs, electronic data, and volatile substances, purifying argon gas, and separating methane, ethane, and propane. Deep drying of gases and liquids such as air, natural gas, hydrocarbons, refrigerants, etc; Preparation and purification of argon gas. Static drying of electronic components and perishable materials; Dehydrating agents in paints, polyesters, dyes, and coatings.

5A molecular sieve is primarily used for natural gas drying, desulfurization, and carbon dioxide removal; Separate nitrogen and oxygen to prepare oxygen, nitrogen, and hydrogen; Petroleum dewaxing separates straight hydrocarbons from branched and cyclic hydrocarbons. 5A molecular sieve can achieve deep adsorption of water and residual ammonia. The decomposed nitrogen hydrogen mixture enters the dryer to remove residual moisture and other impurities. The purification device adopts a dual adsorption tower, with one adsorbing dry ammonia decomposition gas and the other desorbing water and residual ammonia under heating conditions (usually between 300-350), to achieve the purpose of regeneration.