Chemical elements
  Carbon
    Isotopes
    Energy
    Production
    Application
    Physical Properties
    Chemical Properties
    Diamonds
    Graphite
    Amorphous Carbon
      Preparation
      Sugar-Charcoal
      Lampblack and Soot
      Retort Carbon
      Wood-Charcoal
      Animal Charcoal
      Coke
      Physical Properties
      Chemical Properties
      Fusion and Vaporisation
    Coal

Preparation of Amorphous Carbon






Amorphous carbon may be formed in a variety of ways, but its preparation in a state of purity is difficult. It is liberated in the following reactions:

  1. Decomposition of carbonaceous matter at high temperature (sugar, vegetable and animal charcoal, coke).
  2. Deposition from dissociated hydrocarbon vapours (lampblack, soot, gas-carbon).
  3. Explosive decomposition of endothermic compounds, e.g. acetylene.
  4. Deposition in electrolysis:

    1. at anode in electrolysis of silver acetylide;
    2. at kathode in electrolysis of concentrated sulphuric acid with carbon electrodes;
    3. at kathode in electrolysis of fused BaCO3 + BaCl2 at 600° C.
  5. Reduction of CO and CO2 by metals: e.g. CO2 by magnesium, calcium and the alkali metals, and CO by iron at high temperature.
  6. Decomposition of CO:

    1. by heat at 1690° C. into CO2 and free carbon;
    2. by radium emanation into O2, CO2, and carbon.
Sugar-charcoal and lampblack yield the purest forms of amorphous carbon, because they need contain no mineral impurity.


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