China 4A Sieve Factory & Pricelist

Section 1: Molecular Architecture & Fundamentals of Zeolite 4A

Zeolite 4A is a synthetic sodium aluminosilicate featuring a crystalline framework structure belonging to the cubic type A family (LTA topology). Structurally, it is represented by the unit chemical formula: Na₁₂[(AlO₂)₁₂(SiO₂)₁₂]·27H₂O. The effective pore opening of Zeolite 4A is approximately 4 Ångströms (0.4 nm), which limits molecular penetration based purely on steric exclusion. Any molecule with a kinetic diameter smaller than 4 Å—such as water (2.65 Å), carbon dioxide (3.3 Å), sulfur dioxide (3.6 Å), and hydrogen sulfide (3.6 Å)—is rapidly and preferentially co-adsorbed within its internal alpha-cages. Meanwhile, larger molecules, like propane, butane, and branched hydrocarbons, are structurally excluded.

The industrial performance of 4A Molecular Sieve depends greatly on the synthesis method, crystalline purity, and mechanical binding agent quality. Standard raw materials include silicate solutions, sodium aluminate, and caustic soda. Through hydrothermal crystallization, amorphous gels are transformed into highly ordered crystalline structures. The raw powder (Zeolite 4A powder) is then formulated with inorganic binders (typically attapulgite or kaolin clays) and rolled into spheres or extruded into pellets, followed by high-temperature calcination to activate the material. This thermal activation step eliminates structural water, creating an active micro-porous matrix with high affinity for polar compounds.

Section 2: Macro-Industry Solutions & Adsorption Optimization

As industrial processes aim for carbon neutrality and operational efficiency, 4A molecular sieves have become vital components in dynamic adsorption columns. The primary industrial solutions include:

• Industrial Gas Purification & Instrument Air Dehydration: The production of ultra-dry instrument air requires compressed air systems that can achieve pressure dew points below -70°C (-94°F). 4A molecular sieves provide high water adsorption capacities at low partial pressures, outperforming silica gel or activated alumina in deep dehydration processes.
• Natural Gas Sweetening and Treatment: Raw natural gas contains trace moisture, CO₂, and H₂S. In Liquefied Natural Gas (LNG) pre-treatment plants, 4A sieves are used to remove trace water and reduce moisture levels to less than 0.1 ppmv. This prevents ice formation and hydrate crystallization in cryogenic heat exchangers.
• Refrigeration & HVAC Systems: Operating inside closed-loop refrigeration systems, 4A molecular sieves continuously capture moisture that enters through seal leakage or chemical degradation. This stops acid formation and prevents ice blockages in expansion valves.
• Polyurethane and Coating Formulations: Trace moisture in polyols reacts with isocyanates to form carbon dioxide gas, causing pinholes, bubbles, and structural failures in polyurethane coatings, sealants, and adhesives. Adding Zeolite 4A activated powder acts as a physical moisture scavenger, keeping formulations free of bubbles.

Section 3: Key Technical Specifications & Performance Indexes

When buying Zeolite 4A products, evaluating technical parameters helps ensure proper operation in industrial systems. Our 4A molecular sieves are manufactured to precise physical and chemical specifications, minimizing dust creation and maximizing water capacity.

These parameters ensure the molecular sieve can withstand high thermal regeneration cycles without crystalline structural collapse. A low attrition rate prevents dust formation, which can cause downstream blockages in filters, valves, and compressors.