INDUSTRIAL AND ENGINEERING CHEMISTRY
936
+
e
Trial 11. (k,u,b,c)’ =
Vol. 42, No. 5
; C ’ (k,a,b,c)
-
aed
e 0.8531 (k,a,b,c)
Trial 111. Let (k,a,b,c)’ = (0.85368) (k,a,b,c).
For dew point feed the relationship becomes: c = cf
+
1
;
e [acd(a,, - l)(c’
ij d‘)] - 1
+
k’ a’
- 1)
ace(01cd
Le
b’
Olcd ((Yo/
ef
( acol
-
-
C’ _.
f
d
l)(C’ f d ’ ) e’ 1)
F’
a
0.02220 0.01110 0.03756 0,04951 0.58900
11.01 4.20 1.80 P .34 1.0
F’
D’ W’
= 0.67937 = 0.12037 = 0.55900
d’ = 0.50591 (determined as in Trial I).
EXAIIPLE VIII. (kabclde) Mixture. Feed such that B = T. Compute ( L / D ) mfor the complete separation of the following
mixture:
0.058 k
11.01 4.20 1.80 1.34 1.00 0.67
a b
-a C
0.569 0.300
e
=!
0.04951
+
[(E) 0.34
(O-)
0.300 (0.04951 0.04951 0.50591)1] -
+
= 0.05800
+ d‘) -1 - 1) - (0.559) [(1.34)(0.04951) + 0.505911 -
Resolve mixture into (k,a,b,c)‘/d and (k,n,b,c)”/e. Trial I. Let (k,a,b,c)’ = (0.8) (k,a,b,c).
k’ a‘
b’
C‘
d
d=d’+
cd (YW [;bi{aed
F‘
U
0.0208 0.0104 0.0352 0.0464 0.5590
11.01 4.20
( L / D ) m = (L’/D’)m
a
-
1 ) (C’
d(%d
d’ ( k
C‘
+u +b +
c)’(acd
].
(0.50591) (0.12037) (0.34)
1.so
= 14.450
1.34 1.00
J. A. MAY
THEDow CHEMICAL COMPANY FREEPORT, TEX.
+ ]-kid')] -- +
b - 1) (c’ f d’) - 1 ) d‘
(Ycd Gad
=
Effect of Temperature on Density and Refractive Index SIR: In the article, “Effect of Temperature on Density and Refractive Index” by Kurts, Amon, and Sankin [IND. Em. CHENI.,42, 174-6 (1950)], the authors use their simple relation,
Try d’ = 0.50866. ?
0‘559
o’50866
+
0.0352 (1.34) (0.80) (0.0464 0.50866) (1.8) (0.34) (0.50866)
+
[
0.0104 . _ . ~ (1.34) (3.2) (0.55506) (4.20) (0.34) (0.50866)
I-1
+
0.0464 f
(2
0.300
- I ) (0.0464 + 0.50866) (1.34 - 1) (0.0464) 1-11 # 0.0464
as originally proposed by Ward, Kurtz, and Fulweiler (“Science of Petroleum,” Vol. 11, p. 1146, London, Oxford University Press, 1938). By differentiating the Eykman equation, =
dn/dd =
+ 0.00799 = 0.05439
+
C(n 0.4)* (n f 0.4)z 0.84
-
+ 0.03862 + 0.00457 + 0.00715 = 0.55900
(s) 1
An = 0.6 Ad
An/Ad
0.0208 (1.34) (10.01) (0.55506) 0.50866
I-1
+
+
where C is the Eykman constant and n and d are refractive index and density, respectively, taken a t the same temperature [see Dreisbach and Martin, IND.ENG. CHERI.,41, 2875 (1949)]. This gives an accurate coefficient for the first relation. Using the sodium D line and hydrocarbons (as recommended in earlier articles), values of C are frequently between 0.75 and 0.78. The range of An/Ad is rather narrow, usually 0.58 to 0.64, so the constant 0.6 is a good average. But for organic compounds in general, C is almost always below the hydrocarbon range and as low as 0.32 in some instances. An/Ad is below 0.3 for some compounds. This explains the positive and large deviations resulting from the use of the constant 0.6 in Table 111. JOHN GRISWOLD ILLIKOIS INSTITUTE O F TECHNOLOGY CHICAGO, ILL
