Molecular sieves, as a porous material with regular pore structure and excellent adsorption and catalytic properties, have shown wide application value in gas separation and purification, petrochemicals, environmental protection, energy storage and conversion, daily life, and emerging fields. Its core advantage lies in achieving precise separation and reaction control at the molecular level through pore size screening and surface property regulation. The following are the specific applications of molecular sieves in various fields:

1. Gas Separation and Purification

1) Air separation

Oxygen concentrator: 5A molecular sieve (pore size about 0.5nm) preferentially adsorbs nitrogen gas and prepares high-purity oxygen through pressure swing adsorption technology. It is widely used in medical emergency, industrial welding and other fields.

Nitrogen generator: Carbon molecular sieve utilizes the difference in diffusion rate of different gas molecules to separate nitrogen from the air, which is used for food preservation, chemical protection gas, etc.

2) Industrial gas purification

Natural gas dehydration: Molecular sieves adsorb water vapor from natural gas to prevent pipeline corrosion and the formation of liquid water, thereby improving transportation efficiency.

Hydrogen purification: During the hydrogen production process, molecular screening selectively adsorbs impurities such as CO ₂ and CH ₄, improving hydrogen purity to over 99.99% and meeting high-end demands such as fuel cells.

Carbon capture: 13X molecular sieve adsorbs CO ₂ from factory flue gas, helping to achieve carbon neutrality goals.

3) Special gas separation

Nuclear wastewater treatment: Zeolite adsorbs radioactive cesium (Cs ⁺) and strontium (Sr ² ⁺), playing a key role in the treatment of Fukushima nuclear wastewater.

Separation of olefins/alkanes: such as the separation of ethylene (C ₂ H ₄) and ethane (C ₂ H ₆), improves the purity of petrochemical raw materials and reduces production costs.

2. Petrochemical and Catalysis

1) Catalytic cracking

FCC catalyst: Y-type molecular sieve, as the core component of catalytic cracking catalyst, improves the yield of gasoline and diesel, optimizes product distribution, and is the "chip" of the refining industry.

Hydrocracking: High silica Y-type molecular sieves are used in hydrocracking reactions to produce clean fuels and high value-added chemicals.

2) Isomerization and aromatization

Enhancement of gasoline octane rating: ZSM-5 molecular sieve catalyzes the restructuring of light hydrocarbons, converting straight chain alkanes into branched isomers or further aromatizing them into benzene, toluene, etc., significantly improving gasoline quality.

Coal to aromatics: MCM-22 molecular sieve catalyzes coal based methanol to produce p-xylene (core raw material for PET plastics), promoting the high-end development of coal chemical industry.

3) Synthesis of Fine Chemicals

Synthesis of methyl tert butyl ether (MTBE): Molecular sieve catalyst improves reaction selectivity and reduces byproduct generation.

Olefin polymerization: In the production of polyethylene and polypropylene, molecular sieves are used as catalyst carriers to control the molecular weight distribution of polymers.