Molecular sieves are advanced adsorbent materials capable of separating molecules according to their size and polarity. Thanks to their precisely controlled pore structure and extremely large internal surface area, molecular sieves are widely used in industrial drying, gas purification and molecular separation processes.
This capacity is based on the presence of uniformly sized pores, typically ranging from 3 to 10 Angstroms, which selectively allow smaller molecules to enter while excluding larger ones.
Molecular sieves: operating principle and industrial applications
Molecular sieves are commonly used in various technological applications:
- as drying agents, to remove water from solvents and gas, both in the industrial field and in the laboratory; for example, water is a small and polar molecule which can easily enter through the pores of the duly-selected molecular sieve, remaining trapped therein; when saturated, molecular sieves are normally easy to regenerate by removing absorbed water through vacuum heating (130–250 °C)
- for the purification of natural gas which has many uses, such as the removal of CO2, H2S and nitrogenous products
- for the separation of different gases, such as the separation of linear alkanes from isoalkanes in the liquid phase; for example to isolate hydrocarbons C5–C11 from naphtha, or to separate fructose from sucrose and other sugars
