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New method for desorption of wood activated carbon

  • Carrie Ge
    Host
    December 10, 2020
    Wood activated carbon briefly describes a new activated carbon desorption method, this method does not require toxic organic solvents. The use of anionic surfactant solution to dissolve organic solvents from activated carbon, the focus is on its washing and emulsion effects. Isopropanol and methyl ethyl ketone were used as test solvents.



    Place activated carbon in a vial and add a predetermined amount of organic solvent. After standing for about 24 hours, a predetermined amount of surfactant solution was added. pellet activated carbon After an additional 72 hours, the vial was heated in an incubator at 60°C for a predetermined time. Then the frame ionization detector gas chromatograph was used to determine the organic vapor concentration and calculate the desorption efficiency.



    A predetermined amount of organic solvent is adsorbed in the vial by activated carbon, and a surfactant solution is added. The organic solvent in the gas phase is very small, and can be ignored compared with the solid phase when the adsorption equilibrium is established. In fact, we checked the adsorption efficiency using isopropanol and methyl ethyl ketone and toluene and confirmed that the adsorption efficiency was about 100%. After closing the lid, gently shake the vial.



    After that, the vial is placed in an incubator at a predetermined temperature and left for a predetermined time. Then, the vial was placed in an incubator at 60°C and left for about 1 hour. Then, the gas from the headspace of the vial is extracted and injected into a gas chromatograph equipped with a frame ionization detector.



    The activated carbon adsorption method is used to measure low concentrations of organic solvents. This involves collecting the organic solvent vapor in the solid adsorbent by introducing ambient air into a glass tube containing activated carbon with a pump. This method can concentrate target materials by increasing the amount of ambient air that can be sampled. It is necessary to separate the organic solvent by desorbing the organic solvent from the activated carbon.



    Desorption methods include solvent desorption methods and thermal desorption methods. The thermal desorption method is to heat the activated carbon in the tube to over 200°C and analyze the desorbed vapor using gas chromatography. However, this method is rarely used for working environment measurements because it requires expensive equipment.activated carbon suppliers The solvent desorption method uses a desorption solvent to extract the adsorbed organic vapor from the activated carbon, and analyzes the solution by gas chromatography. This solvent extraction method is usually used by most measurement organizations because it does not require special desorption equipment.