Letter | Published:

Number of Free Radicals in Coal During Carbonization at Different Heating Rates


DURING carbonization in vacuo at constant heating rates of 1 and 3deg.C./min. we measured the number of free radicals per gram of starting material of a vitrain with a carbon content of 86.9 per cent. This was done by means of an electron spin resonance spectrometer working at 9,000 Mc./s. The results are given in Fig. 1.

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  1. 1

    van Krevelen, D. W., Huntjens, F. W., and Dormans, H. N. M., Fuel, 35, 462 (1956).

  2. 2

    Smidt, J., and van Krevelen, D. W., Fuel (in the press).

  3. 3

    Austen, D. E. G., and Ingram, D. J. E., Brennstoff Chem., 39, 25 (1958).

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