Fixed-Bed Adsorption Kinetics with Pore Diffusion Control SIR: Professor Bischoff's comments do indeed appear correct. We did derive our solution directly by a method which was easily generalized (as it happened, we labeled our function g(y) and carried through the algebra with that form). It turns out that our procedure was similar to that of Bowen and Lacey. Both papers were unknown t o us a t the time of submission, and because we are not active in the field, we
did not see them when they appeared. Perhaps the slight difference in application (catalyst beds us. ion exchange) and the timing caused the reviewers also to miss this.
Ralph S . Cooper
University of California L~~~i~~~~ Scientific Laboratory Los Alamos, New Mexico 87544
Correction THREE-PARAMETER FORMULATION OF THE JOFFE EQUATION OF STATE I n this article by H. E. Barner and S. B. Adler [IND.ENG. CHEM.,FUNDAM. 9, 521 (1970)1, the following errata have been found. (a) I n Equation 9 the last term should be cf,/RT instead of being negative. (b) In Equation 22 the third term to the right of the equals sign should again be preceded by a plus sign instead of a minus sign, as
+
Ha - H
=
RT - p V + -In b4
(; ~
b ) etc.
(e) Equation 20 should be entirely rewritten as follows
In$
= z
328
- 1 - In p(V
- b)
RT
afa +--InRTb
V -b V
Ind. Eng. Chem. Fundam., Vol. 10, NO. 2, 1971
+
'-[-
RTb
1
V-b
1
+-Inb
+
V
2 V - b b(V - b ) + g l n - ] - - gV[ 2
1
2b2(V - b)'
1
3b(V - b)a 1 - -___ - .- In b3(V - b) b4
+
v-bl
~
V
These errors developed during a simplification of the nomenclature for purposes of publication. The results and the conclusions in the paper are quantitatively and numerically correct. The errors in the equations developed during the transposition of nomenclature. We regret these errors and the inconveniences that arose from them.
