October, 1942
INDUSTRIAL AND ENGINEERING CHEMISTRY
vertical line is drawn to the curve and the process repeated. The vertical line from point c intersects the X , axis before reaching the curve so that the next horizontal line would lie below X,+ = X/ = 0.0. The required number of units is therefore 4.
Nomenclature S,s = pounds of solute in clear liquid and sediment, respec-
tively, per ound of inert solid in sediment pounds of sogtion (solute plus solvent) in clear liquid and in sediment, respectively, per pound of inert solid in sediment X = concentration of clear solution, pounds of solute per pound of solution Subscripts d = streams delivered by the system f = streams fed to the system m = last unit in the system (the least concentrated) n = number of unit, counting from more concentrated end 1,2,etc. = number of unit from which the stream is leaving
W ,w
=
1231
Literature Cited (1) Badger and McCabe, “Principles of Chemical Engineering”, pp. 423-34, New York, McGraw-Hill Book Co., 1936. (2) Baker, E. M., Chem. & Met. Eng., 42, 669-71 (1935); Trans. Am. Inst. Chem. Engrs., 32, 62-72 (1936). (3) Donald, M. B., Trans. Inst. Chem 4ngrs. (London), 15,77-109 (1937). (4) Elbgn, J. C., Trans. Am. Inst. Chem. Engrs., 32,451-71 (1936). (5) Griffin, C.W.,IND.ENG.CHQM., ANAL.ED.,6,40-1 (1934). 9, 866-71 (1917); 12, 492-6 (6) Hawley, L. F.,IND.ENG.CHHIM., (1920). (7) Xammermeyer, Karl, Ibid., 33,1484-91 (1941). (8) Ravenscroft, E.A.,Ibid., 28,851-5 (1936). (9) Sanders, M. T., Chem. & Met. Eng., 39, 161-2 (1932). (10) Tsao, Yu Teh, J. Chem. Eng. China, 4,164-8 (1937). (11) Work, L. T., and Kohler, A.. S.,Trans. Am. Inst. Chem. Engrs., 36, 701 (1940). , PREBENTBD before the Division of Industrial and Engineering Chemistry a t the 104th Meeting of the AMHRICAN CHEMICAL Socmm, Buffalo, N. Y.
Surface Tension-Viscosity Nomograph for Organic Liquids D. S . DAVIS Wayne University, Detroit, Mich.
F
OR thirty-two organic compounds Buehler (I) drev attention to an important relation between surface tension and viscosity:
+
1% (log 9) 2.9 I/P surface tension, dynes/cm. viscosity, millipoises, at same temperature as 7 viscosity-constitutional constant parachor E
where y = Q
=
I = P =
’*I
The table lists compound numbers and values of I / P
(1,4) for the organic liquids in question. No. 15 6 17 3 10 11 7 16 17 13 5
”I
17 13 4
20
/
_I K)
/----
20 12
I/P 1.226 1.195 1.253 1.186 1.205 1 208 1: 198 1.243 1.253 1.217 1,192 1.253 1.217 1.190 1.303 1.212
Compound Acetate, ethyl Acetate, methyl Acetate, propyl Acetone Benzene Benzene ethyl Bromide: ethyl Bromide, isobutyl Bromide, isopro yl Bromide, propyf Bromobenzene Chloride, isobutyl Chloride, propyl Chlorobenzene Decane Ether, ethyl
No. 12 18 17 10 1 14 14 12 10 2 19 9 8 11 15 13
I/P 1.212 1.286 1.253 1.205 1 103 1:222 1.222 1.212 1.206 1.172 1.280 1.202 1.201 1.208 1.226 1.217
Compound Formate, ethyl Heptane Hevane Iodide ethyl Iodide’ methyl Iodide: prppyl Ketone diethyl Ketone: methyl ethyl Naphthalene Nitrobenzene Octane Tolune m-Toluene m-Xylene o-Xylene p-Xylene
The use of the nomograph, constructed to solve the equation conveniently and accurately, is illustrated as follows: What is the surface tension of ethyl iodide a t 16’ C. when its viscosity is 6.2 millipoises (3) at this temperature? The compound number for ethyl iodide, read from the table, is 10. Connect 6.2 on the 7 scale with 10 on the compound number scale and produce the line to the y scale where the surface tension is read as 29.1 dynes per em. The experimental value reported in the International Critical Tables (2) is 29.9.
Literature Cited (1) Buehler, C.A.,J.Phys. Chem., 42,1207 (1938). (2) International Critical Tables, Vol. IV, p. 436, New York, McGraw-Hill Book Co., 1028. (3) Perry, J. H.,Chemioal Engineers’ Handbook, 2nd ed., p. 794, New York, McGraw-Hill Book Co., 1941. (4) Soudera, Mott, Jr., J . Am. Chem.Soc., 60,154 (1938).