The main characteristics of molecular sieve

  1. Physical characteristics:
    Specific heat: about 0.95 KJ/KgXK (0.23 Kcal/KgX°C
    Thermal conductivity (dehydrated): 2.09KJ/MXK (0.506Kcal/mX°C).
    Water adsorption heat: about 3780KJ/kg (915Kcal/kg)
  2. Thermal stability and chemical stability:
    The molecular sieve can withstand a short high temperature of 600-700 °C, but the regeneration temperature is generally below 400 °C. Molecular sieve can be used in media in the pH range of 5-10; Certain metal cations can be exchanged in salt solutions.
  3. Characteristics of molecular sieve:
    Molecular sieve is a kind of crystalline aluminosilicate, which has many excellent characteristics due to its uniform pore size and extremely high specific surface area.
    (a) Selective adsorption according to the size and shape of molecules, that is, adsorbing only those molecules smaller than the pore size of the molecular sieve.
    (b) For small polar molecules and unsaturated molecules, it has selective adsorption performance, the greater the polarity, the higher the degree of unsaturation, and the stronger its selective adsorption.
    (c) It has strong water absorption. Even at higher temperatures, large airspeeds and lower water content, there is still a fairly high water absorption capacity.
  4. Basic features:
    a) Molecular sieve can be reversibly adsorbed and desorbed of water or various gases, liquid compounds.
    b) Metal cations are easily exchanged.
    c) The internal cavities and channels of the molecular sieve form a very high internal surface area. Its inner surface can be 10,000-100,000 times higher than the outer surface area of molecular sieve particles.

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