Synthesis of 5A molecular sieve for hydrogen purification in pressure swing adsorbers

5A molecular sieve is used in petroleum and gas industries as an adsorbent, especially for hydrogen purification. In this study, 5A molecular sieve for hydrogen purification in pressure swing adsorber (PSA) is synthesized, and its physical properties are reported. At the first stage, the 4A zeolite powder produced as the precursor of 5A zeolite is prepared using hydrothermal method with the molar ratio of SiO2/Al2O3≈1.5, and then kaolin powder as binding agent is used for preparing extrudates. Then, these pellets were converted to 5A type through ion exchange process using calcium chloride solution. After determining physical properties, adsorption tests for the separation of CH4 and CO from a feed stream (H2=89.9 mol%, CH4= 10 mol%, and CO=0.1 mol%) under severe operating conditions (P=40atm, T=40°C, and GHSV from 1200 to 1750 h-1) are carried out in a laboratory scale fixed-bed adsorber. Results show that the synthesized 5A molecular sieve has acceptable physical properties in comparison to data reported in literature. Moreover, a breakthrough time about 27 sec can be expected.

کلیدواژه ها:

Adsorption ، Molecular sieve 5A ، Pressure swing adsorption (PSA) ، Hydrogen