Dispersibility of Coal in a Supersonic Field

Article metrics


IN the course of experiments on the solubility (or dispersibility) of coals in organic solvents, it was observed that the pyridine-insoluble (α) fraction of a Northumberland coal (82·6 per cent carbon and 5·1 per cent hydrogen on the dry ash-free basis) became partially dissolved (or dispersed) when suspended in pure dry pyridine and exposed to supersonic waves (c. 25 kc./sec.) for 15 min. When the extract thus formed was recovered by removal of the solvent under reduced pressure in an atmosphere of dry oxygen-free nitrogen, it formed a black, free-running solid that was only very slightly soluble in boiling pyridine. The elementary composition of this material was practically identical with that of the original α-fraction, both being reduced to the pure coal basis.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Kiebler, M. W., Carnegie Inst. Contrib. No. 87 (1942).

  2. 2

    Bangham, D. H., Introductory Lecture, Conf. Ultraflne Structure of Coals and Cokes (BCURA, 1944).

  3. 3

    Dryden, I. G. C., Nature, 162, 959 (1948). Berkowitz, N. (unpublished work).

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

BERKOWITZ, N. Dispersibility of Coal in a Supersonic Field. Nature 163, 809–810 (1949) doi:10.1038/163809b0

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.