Change in Surface Area of Anthracite on Heat Treatment

Abstract

Maggs¹ and Malherbe², among others, have shown that coal behaves as a molecular sieve material. That is, the adsorption of nitrogen and argon at 77° K. is restricted because of activated diffusion into pores of molecular dimensions and gives data only on the readily accessible macropore area of coal. From heats of wetting and gas-adsorption data at higher temperatures, the macropore area is shown to represent an insignificant part of the total surface area of most coals.