Application of 4A Molecular Sieve Adsorbent in Gas-Liquid Drying
Structure and performance parameters of 4A molecular sieve: 4A molecular sieve is an artificially synthesized zeolite, a crystal of silicate and aluminate, which is white in powder form. After adding a binder, it can be extruded into strips, flakes or balls. 4A molecular sieve is non-toxic, odorless, and non-corrosive. It is insoluble in water and organic solvents but soluble in strong acid and strong alkali. When heated, 4A molecular sieve loses its crystalline water, forming many small holes inside the crystal. The pore size is similar to the diameter of gas molecules, and they are very uniform. It can suck in molecules smaller than the pore size and block molecules larger than the pore size. Therefore, it can separate various components according to the size of the molecules, hence the name “4A molecular sieve”. Today, we will talk about the application of 4A molecular sieve adsorbent in gas-liquid drying.
4A molecular sieve has a special affinity for water and has a strong water absorption capacity. Therefore, it is widely used in gas drying and is an ideal desiccant. At the same time, 4A molecular sieve has stable properties, is heat-resistant, water-resistant, and can withstand erosion from various solvents. Even after multiple regenerations, it can still maintain good adsorption performance and can be used for a long time. Below are some examples of using 4A molecular sieve in gas drying.
Drying of air with 4A molecular sieve
In the process of producing pure oxygen and nitrogen from air separation, water and carbon dioxide must be removed from the raw air to maintain normal equipment operation. Using 4A molecular sieve as a desiccant, it can simultaneously absorb and remove water, carbon dioxide, and acetylene from the air, and the effect is very good. This simplifies the process, reduces equipment usage, eliminates corrosion, and ensures normal operation.
Drying of rare gases with 4A molecular sieve
Rare gases are important raw materials commonly used in industry. When these gases are used for a special application in industry, deep drying is often required. 4A molecular sieve is an excellent adsorbent for deep drying of these gases, and its performance is superior to other adsorbents.
In the electronics industry and nuclear reactors, ultra-pure hydrogen and argon are often used as reducing gas and cooling gas. To obtain these high-purity gases, 4A molecular sieve adsorption drying is also widely used. For example, when removing trace water from electrolytic hydrogen using 4A molecular sieve at liquid nitrogen temperature, the water content in hydrogen can be reduced to below 0.05PPM. Adsorption drying of electrolytic hydrogen at room temperature can also remove residual moisture in hydrogen to as low as 0.1-0.25PPM.
4A molecular sieve powder is also an important drying agent in helium separation industry. For example, a helium factory uses ethylene glycol freezing dehydration. Due to incomplete removal of water, pipeline blockage often occurs. Later, 4A molecular sieve was used as a desiccant to completely solve the pipeline blockage problem.
