387.     ------.  [BRUNAUER, S., AND EMMETT, P. H.]  Use of Low-Temperature van der Waals’ Adsorption Isotherms in Determining the Surface Areas of Various Adsorbents.  Jour. Am. Chem. Soc., vol. 59, 1937, pp. 2682-2689; Chem. Abs., vol. 32, 1938, p. 1159.

      Van der Waals’ adsorption isotherms of some or all of the following gases were determined on a variety of adsorbents at the temperatures indicated:  A and N₂ at –195.8°; A, N₂, CO, and O₂ at –183°; CO₂ at –78°; normal C₄H₁₀ and SO₂ at 0°.  The following adsorbents were used:  2 Cu catalysts, glaucosil, pumice, NiO supported on pumice, Ni on pumice, dry powdered bacteria, Cr₂O₃ gel, “glowed” Cr₂O₃, KCl, CuSO₄·5H₂O, CuSO₄, 2 SiO₂ gel samples, activated charcoal, and 2 Darco samples (activated carbons).  All adsorbents except charcoal given sigmoid isotherms, and the values for the surface area evaluated from the different isotherms for the same adsorbent were consistent with one another.