W i l l i a m A. Pardee a n d W h i t n e y W e i n r i c h GULF RESEARCH & D E V E L O P M E N T C O . , PITTSBURGH, P A '
The alkyl derivatives of phenol have recently been developed and used in the manufacture of synthetic rubber, plastics, petroleum products, etc. Physical data on these compounds are essential to engineering calculations for design of plants for their production. Dafa on 60 such compounds have been assembled and correlated inthis report. Experimental data oh vapor pressure, viscosity, melting point ,and specific gravity are reported. Few data are available on such properties as thermal conductivity, heat of vaporization, specific heat, and heat of reaction; since measurement of these properties requires specialized apparatus and technique, methods were devised for their calculation. N Operator at the left is observing the liquid level in a gage glass attached to a fractionating tower which operates at high pressure and temperature, used in investigations at Gulf's Chemical Engineering Laboratories.
-
HE study of alkylated phenols has been in progress a t Mellon Institute (SO) and in this laboratory (33) for a number of years, and during this time considerable information on the physical properties of these compounds has been accumulated by the men associated with the work. Data on boiling points, melting points, densities, and viscosities can be obtained by relatively simple means in the laboratory; but properties such as thermal conductivity, specific heat, heat of vaporization, and heat of reaction require specialized equipment and technique. Since these properties are, however, an essential part of the information needed in process design, it has been necessary to use the meager d a t a in the literature as a guide in the calculation of generalized charts of these properties. Experimental determinations which appear in the literature at a later date may require revision of the charts presented here; but in the process design work done so far, t h e calculated values, in conjunction with the available experimental values, have been satisfactory. The object of this report is to bring together the pertinent data on alkylated phenols. Complete coverage of all phenolic compounds in the literature has been avoided purposely because few, if any, are encountered a t present. For those that do become of interest, the ground work for the calculation of needed data is laid here.
T
V A P O R PRESSURE
All vapor pressure data found in the literature and in private communications have been accumulated. When the data over the pressure range 20-760 mm. mercury were plotted on logarithmic coordinate paper, a better straight line resulted than when
they were plotted on the conventional coordinates of logarithmic pressure vs. reciprocal temperature. However, the logarithmic plot is inaccurate a t pressures much lower than 20 mm. mercury. Figure 1 is a nomograph based on the logarithmic plot. It contains the vapor pressure data available on fifty-four of the sixty compounds listed in Table I. References to the original vapor pressure data are given in parenthesis in the column of boiling points a t 20 mm. pressure. Original data were plotted, and the boiling points listed in Table I were taken from the smoothed curves. When only one boiling point was available, a curve was drawn through the point so that it fitted into a family of curves representing similar compounds on which complete data were available; the compounds for which the data were obtained in this manner are indicated with an asterisk in the figures and in Table I. The vapor pressure data on compounds which are handled in semicommercial opeqations and, consequently, are referred to more frequently than the other less familiar compounds, are plotted on logarithmic us. reciprocal temperature charts in Figure 2. While these curves may be used more conveniently and a t lower pressures (below 20 mm. of mercury) than Figure 1, the latter covers a higher pressure range with almost as good accuracy. It is estimated that the nomograph may be read with a precision of at least * 2 O C.2 Present address, Petroleum Administration for War, Washington, D. C. of the full-scale nomograph (approximately 12 X 16 inches) may be obtained upon request from William A. Pardee. This nomograph m a p be read with a piecision of about * 1a C. I
n A print
595
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vd. 36, No. 2'
INDUSTRIAL A N D ENGINEERING CHEMISTRY
July, 1944
Figure 1.
597
Vapor Pressures of Phenolic Compounds
An *aterisk* indicrtm that expedmental d.t. ate Incomplete, thew data w m obtained kom "lmllv" e w e plot uslns II single exwCinn 1
38*
3 3
26 33*
2
7 6
2-Ethylphehol 3-Ethylphenol 4-Ethyl henol 2-Propy?phenol 3-Pronvlnhenol
I
4-tert-Butylphenol 2-n-Butylphenol 3-n-Butyldhenol
.
'
.
38* 37*
6 5*
22 34 29 35
4 9 8 13*
2a* 30* 24 32 44
16 11
17 19* 10
25
23 14
31 31 12 27 20
16
21
.
la*
48 36
47 39 45*
43* 49*
40* 50 41
45 42
'"
100
, 3 0 4,$
;'7 f
w
a 170*
2 :3 I90
60
+
22
230* 240
250*
290
30
i
350-f-
20
.
15
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 36, No. 'I
INDUSTRIAL A N D ENGINEERING CHEMISTRY
July, 1944
599
Figure 2. Vapor Pressure Data A . PHElNOL AND teTt-BUTYLPHElNOLS Phenol 2-tert-Butylphenol 3-tert-Butylphenol 4-tert-Butylphenol 2,4-Di-tert-b utylphenol 2,4,6-Tri-tert-butylphenol B . CRESOLB A N D left-BUTYLCRBSOLB 2-Methvlohenol
C6H6O CioHirO CirHznO CiaHaoO CiHeO
1
2 4
a
5 6
1 2 2
CllHl60
3
6 5 4 8 9
CiaHuO
c.
7
ETIXYLPHENOLS A N D tert-BUTYLElTHYLPHElNOLS
CsHioO CizHisO Cl6H26O
D. CiHibO
CinHisO
CIEHZ~O
2-Ethylphenol 3-Ethylphenol 4-Ethylphenol 2-Ethyl-2-tert-butylphenol 2-Ethyl-y-tert-butylphenol 3-Eth yl-r-tert-butylphenol 4-Ethyl-2-tert-butylphenol 2-Ethyl4 6-3-tert-butylphenol 3-Ethyl-4:6-dj-tert-butylphenol 4-Ethy1-2,6-di-tert-butylphenol XYLENOLS AND terl-BUTYLXYLENOLB 2,3. Xmethylphenol 2,4. Xmethylphenol 2,5. Xmethylphenol 2,6, Xmethylphenol 3,4. Xmethylphenol 3,5. limethylphenol 2,3, 3imethyl-2-tert-butylphenol 2,3. Iimethyl-y-tert-butylphenol 2 4. Xmethyl-6-tert-butylphenol 2:5, 3imethyl-4-tert-butylphenol 2,6, 3imethyl-4-tert-butylphenol 3,4. Xmethyl-6-tert-b utylphenol 2.3. ~imethyl-4,6-di-tertbutylphenol
1 2 3 4* 6* 7*
.. . ...
...
...
*.
.. .
. .. .
...
....
....
4-Methyl-2:B-di-tert-butylphenol 3-Methyl-4-dijsobutylphenol 4-Methyl-2-dilsobutylphenol
8
CsHioO
3 1
CinHiaO
1 2* 5 4 8* 9* 6 10 7 9 11*
... ...
F.
Figure 3. Specific Gravity Data CRBSOLB, AND tert-BUTYL DBRIYATIVEI A . PHENOL, Phenol CsHsO 2-Methylphenol CiHsO 3-Methylphenol 4-Methylphenol 2-Methyl-~tert-butylphenol CiiHisO 2-Methyl-y-butylphenol 3-Methyl-z-tert-butylphenol 4-Methyl-2-tert-butylphenol 2-Methyl-4,6-d~-tert-butylphenol CisHnrO 3-Methyl4 6-di-tert-butylphenol
9* 10
II.
. . ..
TEMPERATURE,
5
Comparison of Values Calculated b y Two Equations Smith Equation ( d g ) , 30' C. (86' F.) Cragoe Equation (9) k (Calod./ k (CalodJ Comexptl. k exptl.) T z m g , exptl. k exptl.) (29) calcd. X 100 (80) oalod. X 100 pound m-Cresol 0.0968 86.6 0.0641 Thymol 55.4 0:0?58 0.0693 91 Benzene 0:0920 0:6624 101 53.6 0.0807 0.0767 95 100 32 0.0845 0.0782 93 Toluene 0.0882 0.0882 53.6 0.0743 0.0778 105 o-Xylene 0:09Oa 0:6ii 96 6 9 . 8 0.0903 0.0760 84 m-Xylene 0.089 0.084 94 EthvlbeGzene 0.086 0.085 99 p-Cymene , 5i:6 0:0668 0:6?87 120 5 At 69.8' F. (21 O C.) Table
.e4
B. XYLIQNOLS AND tert-BUTYL DERIVATIVES 2 5-Dimethylphenol ' 3'4-Dimethylphenol 3'6-Dimethylphenol 2:4-Dirnethyl-6-lert-butylphenol 2 6-Dimethyl-4-tert-butylphenol 2'6-Dimethyl.4-tert-butylphenol d,4-Dimethyl-6-tert-butylphenol
3 1 2 6 4
7
5
A simple equation proposed by Cragoe (9) involves the use of specific gravity a t 6Oo/6O0 F. and temperature. A comparison of conductivities calculated by this equation with available experimental data on several compounds shows a maximum deviation of about 20% with an average of about ll%,as shown in Table I1 where the Smith and Cragoe equations are compared. Cragoe's equation, revised to give the desired units, follows:
IC=-
'?'
[I
- 0.0003 ( t - 32)]
(1)
where k = thermal conduc$ivity, (B.t.u.)(ft.)/(hr.)(sq. ft.) ( " F.) t temperature F. d specific g r a d t y a t 6Oo/6O0 F. 5
E
It is clear that one can rely on neither of the methods when applied to phenols. If an accuracy of 10-20'% is satisfactory, either method may be used a t the lower temperatures, and the comparisons seem to indicate that Smith's equation gives the better agree-
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 36, No. 7
ment with the above compounds. The variation with temperature, as indicated by Cragoe’s equation, is less than the tested accuracy, so the best method to be recommended at this time is to w u m e that a conductivity calculated either by the Smith or Cragoe equation is constant over the temperature range of about 0” to 200” C. (32’ to 392’ F.).
LATENT H E A T O F V A P O R I Z A M
There are few experimental data on the latent heat of vaporization of phenolic compounds; therefore, i t has been necessary t o find some means of approximating this property. Othmer (34) reports a method for estimating latent heats of vaporization in which he graphically solves the equation,
MI log p = __ log p’ M’l’
+c
(2)
where M , M‘ = molecular weights of compound and reference compound, respectively I , 1‘ = latent heats of vaporization at boiling points and pressures p and p ‘ of compound and reference compound, respectively C = a constant The agreement of the latent heat of vaporization of rn-cresol reported in the literature with that calculated by the above method is within 2y0 when water is used as the reference material. It is concluded that this method is sufficiently accurate for the estimation of latent heats of vaporization of the phenolic compounds. Figure 5 is a plot of latent heat of vaporization against temperature for twenty-nine of the compounds listed in Table I-namely, phenol, cresols, ethylphenols, xylenols, and tert-butyl derivatives of these compounds. The reference substance used” in the calculations for this plot was water, and the necessary vapor pressure and latent heat data for water were obtained from Keenan (18A). Vapor p’ressures for the phenolic compounds were taken from a large scale nomograph, similar t o Figure 1. SPECIFIC H E A T
Several correlations have been reported for calculation of specific heats of liquid hydrocarbons. hlost of these correlations are based on specific heat data of petroleum fractions from different base stocks. Some of these correlations were compared with
Figure 4.
t
A. CcHsO CrHsO
Phenol 5-Methylphenol 3-Methylphenol 4-Methylphenol 2-M ethvl-s-tert-butylphenol 2-Meth&u-tert-butylphenol 3-Methyl-s-tert-butylphenol 4-Methyl-2-tert-butylphenol 2-Methyl-4 6-di-tert-butylphenol 3-Methyl-4’6-di-tert-butylphenol 4-Methyl-2’6-di-tert-butylphenol,
CiiHisO
CirHzrO
E. CaHioO CiPHiSO
Viscosity Data
P H E N O L , CRESOLS, AND t e r t - B U T Y L D E R I V A T I V E S
3-1\Iethyl-4~diisobutylphenol 4-I+fe.thyl-2-diisobutylphenol XYLENOLS AND t e r t - B U T Y L DERIVATIVES 2 5-Dimethylphenol
3’5-Dimethylphenol 3’4-Dimethylphenol
2’4-Dimethyl-6-tert-butylphenol 2’5-Dimethyl-4-tert-butylphenol 2:6-Dimethyl-B-tert-butylphenol 3,4-Dimethy1-6-terl-but~lphenol
2 1 3 5
4 8 6
7 10
13
9 11 12
INDUSTRIAL A N D ENGINEERING CHEMISTRY
July, 1944
the available data on the phenolic compounds; it was found that the equation which gave results most nearly in agreement with the available experimental data was that for castor oil given in International Critical Tables (18): 0.5
4 + 3.89 X
cp = -
10-4t
- 0.0229
(3)
where e, = specific heat, cal./(gram)( O C.) or B.t.u./(lb.)(' F.) d = specific gravity at 60" FJ4" C. (Equation 3 as given in International Critical Tables, Volume 1, page 151, employs specific gravity at 15'/4' C. which corresponds to 59" FJ4" C.; since most specific gravities in this paper are expressed at 60' F./4" C., the difference of 1' F. has been neglected.) t = temperature, ' F. Equation 3 was checked with specific heat data, reported in the literature on phenol, v --e-11, thymol, carvacrol, pyrocatechol, Phenol 2-Methylphenol 3-Methylphenol 4-Methylphenol) 4-tert-Butylphenol 2-Methyla-~ert-butylphenol 2-Methyl-ytert-butylphenol 3-Methyl-z-tert-butylphenol 4-Met hyl-2tertbutylphenol
2-Methyl-4,6-di-tert-butylphenol 3-Methyl-4,6-di-tert-butylphenol 4-Methy1-2,6-di-tert-butylphenol
resorcinol, and hydroquinone. The maximum deviations are +Z% and -4%. Data used and results obtained in calculating the deviations are given in Table 111. The equations derived for phenol, cresols, and tert-butyl derivatives are given below (Equations 4 to 12). They were used in calculating data plotted in Figure 6. To estimate the heat of the isobutylene-phenol reaction as a function of temperature, it is necessary to have a n equation for the specific heat of isobutylene vapor. Very few experimental data were immediately available for the specific he%tof isobutylene; therefore an equation was derived using Einstein functions and bonding frequencies. Dobratz (10) illustrates the use of this method, and the values of the different bonds as reported in this reference were used in conjunction with the critical constants of isobutylene reported byjBeattie, Ingersoll, and Stockmayer ( 6 ) , (t, = 144.7' C., p , = 39.48 atm.) t o derive the following equation for isobutylene:
++ 3.89 X 3.89 X + 3.89 X lO-4t ++ 3.89 X 10-41 3.89 X cp = 0.484 + 3.89 X lO-4t cP = 0.494 + 3.89 X 1O-V cp = 0.489 + 3.89 x lo-% c, = 0.491 + 3.89 X lO-4t
c p = 0.460 cp = 0.465 cp = 0.469 cp = 0.481 cP = 0.486
where c, = isobaric specifi? heat a t 1 atm., (B.t.u.)/(lb.)( t = temperature, F.
lO-4t lO-4t
(4)
cp = 0.261
(5)
lO-4t
O
601
F.) or cal./(gram)('C.)
+ 5.292 X 10-4t - 1 . 1 2 x 10-7t2
(13)
The specific heat of diisobutylene liquid as calculated from an equation of Cragoe (9) follows: c, =
0.457
+ 5.3 X
10-4t
(14)
Equation 14 is used in the next section in the calculation of the heat of polymerization of isobutylene. HEAT OF REACrlON
There are no published data on the heat of butylation of phenolic compounds; therefore data necessary for design purposes had to be estimated by the best means possible. Since no heat of combustion or formation data have been published on the tert-butyl derivatives, the primary problem resulted in the calculation of these heats. Combustion data are reported for phenol, the cresols, and isobutylene, so it was necessary only to estimate by some means the heat of combustion of the tert-butyl derivatives. The most reliable method is thought to be one in which bonding energies are used in conjunction with the heats of combustion of a
Figure CeHsO CiHaO
CaHioO
CoHiaO
Phenol Z-Methylphenol 3-Methylphenol 4-Methylphenol 2,s-Dimethylphenol 2 4-Dimethylphenol $5-Dimethylphenol 2,6-Dimethylphenol 3,4-Dimethylphenol 3.5-Dimethylphenol 2-Ethylphenol 3-Ethylphenol 4-Ethylphenol 2-prop yipheno 3-Propylphenol 4-Propylghenol
5. Calculated Latent H e a t of Vaporization Data
CloHuO
CiiHisO
4 4 4 5
CigHisO
2-tert-Butylphenol 10 3-tert-Butylphen 01 4-tert-Butylphenol 2-n-Butylphenol 3-n-Butylphenol 4-n-Butylphenol 2-Methyl-s-tert-butylphenol 2-Methyl-y-tert-butylphenol 3-Methyl-r-tert-butylphenol 4-Methyl-2-tert-butylphenol 4-Methyl-2-sec-butylphenol 2-Methyl-4-tertamylphenol 3-Methyl-4-tert-amylphen 01 4-Methyl-2-tert-amylphenol 2,3-D~methyl-s-tert-butylphenol 2,3-Dirnethyly-tert-butylphenol
CizHisO (Cont'd) 2,6-Dimethyl-4-tert-butylphenol 2,4-Dimethyl-6-tert-butylphenol 2,5-Dimethyl-4-tert-butylphenol 3.4-Dimethyl-6-tert-butylphenol 2-Ethyl-2-tert-b utylphenol 2-Ethyl-y-tert-butylphenol 3-Ethyl-s-tert-butylphenol 4-Ethyl-2-tert-butylphenol 2 4-Di-tert-butylphenol 4:Diisobutylphenol 2,4,6-Triallylphenol 2-Methyl-4 6-di-tert-butylphenol 3-Methyl-4'6-di-tert-butylphenol 4-Methyl-2'6-di-tert-butylphenol 3-Methyl-4~diisobutylphenol 4-Methyl-2-diisobutylphenol 2,3-Dimethyl:4,6-di-tert-butylphen101 2-Ethyl-4 6-di-tert-butylphenol 3-Ethyl-4'6-di-tert-butylphenol 4-Ethyl-Z:B-di 4-Methyl-2.6-di-tert-amyl~henol t.ert-butylphenol
-
2,4,6-Tri-tert-butylphenoi
13
14
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INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 36, No. 7
Using the heat of combustion of 2-methyl-5-tert-butylphenol calculated by the bond energy method and heats of combustion of liquid o-cresol and gaseous isobutylene given in Table IV, the heat of the butylation reaction a t 20" C. was calculated (the difference between the heat of combustion of hydrogen and methane a t 18" and 20' C. was neglected) :
$ *e
+
O - C H ~ C B H ~ O H (iso-CdHs(g) ~) -+ CHI(C~H,)C&,OH(I) AHzo = 18.8 .5
P TEMPERATURE, F.
Figure 6. Specific Heats of Liquid Phenol, Cresols, and tort-Butyl Derivatives CaHsO Phenol 7 2-Methylphenoi CiHaO 6 3-Methylphenol 6 4-Methylphenol 6 4-tert-Butvl~henol CiaHitO 5 CllHl6O 4 4 4
4 1 3 2
ClrHuO
phenolic compound (such as phenol, cresol, or carvacrol) on which data are available, methane, and hydrogen. The bonding energies are those reported by Pauling (25), and the heats of combustion of methane and hydrogen are those reported by Bichowsky and Rossini (6). As an example of the use of this method, the heat of combustion of 2-methyl-5-tert-butylphenol was calculated. The base skeleton of carvacrol (2-methyl-5-isopropylphenol) was used, one hydrogen (from the secondary carbon of the isopropyl group) being replaced by a methyl group, CHs*. The asterisk is used to distinguish a radical or atom from a molecule, and &Hvalues are given as kg.-cal./gram mole:
(15)
This mean? that 15.8 kg.-cal. are released for each gram mole of isobutylene reacting a t 20' C. with o-cresol (603 B.t.u. per pound of isobutylene reacting) to form 2-methyl-5-tert-butylphenol. I n view of the many assumptions made in obtaining the heat of combustion of the tert-butylcresol, it is probably within the accuracy of the method to assume that this heat evolution would be the same for the reaction of isobutylene with phenol, m- and p-cresol, xylenols, and tert-butyl derivatives of these compounds (that is, to form di- and tri-hrt-butylphenols). The variation of this heat of butylation with temperature may be estimated by use of heat capacity Equations 4 to 12. The variation of AH with temperature for Reaction 15 may be expressed by the equation:
+
AH = 32.808 14.86t - 0.00385P where AH = heat of reaction, B.t.u /Ib. mole isobutylene reacting t = temperature, F.
(16)
Since polymerization of isobutylene takes place to some extent in any of these alkylation reactions, it may be necessary to take the heat of this reaction into account. Therefore, by using the heats of combustion of isobutylene and diisobutylene, thc heat evolved in the reaction of 2 moles of isobutylene vapor to form 1 mole of diisobutylene liquid a t 20" C. wak calculated to be 674 B.t.u. per pound of isobutylene reacting. There is considerable disagreement between the heat of polymerization calculated here and that reported by Nelson (21). He stated that the heat of polymerization was about 374 B.t.u. per pound of isobutylene reacting; the source of the data is not indicated. The equation for
AH = 1511.7
Another method is one in which an average value of a carbon in the isopropyl group of carvacrol has been added t o the heat of combustion of carvacrol. For example, the difference in heat of combustion of carvacrol and o-cresol is 1354.5 882.6 = 471.9 kg.-cal./mole. The average effect of each carbon in the isopropyl group is 471.9/3 = 157.3 kg.-cal./mole. This assumes t h a t the hydrogen on the secondary carbon of the isopropyl group has the same effect on the heat of combustion as the hydrogen attached to the ring carbon. If this value of the CHs* group is added to the heat of combustion of carvacrol, a value of 1511.8is obtained, and this is thought to be a good approximation for the heat of combustion of 2-methyl-5-tert-butylphenol. This value is in excellent agreement with that calculated above by bond energies (1511.7 kg.-4.). I n applying these methods to estimate heats of combustion of other tert-butylcresols and tert-butylphenols, the deviation was found to be less than 1%in each case. Heat of combustion data used in these calculations are listed in Table IV.
-
2 p o u n d m o l e s of gaseous isobutylene react t o form 1 pound mole of liquid diisobutylene a t t F. is represented by the equation: O
AH = 74,107
+ 21.946 + 1 X 10-4t2+ 4.18 X 10-6t3
(17)
Data from a test run period on the semicommercial plant (39) were used to estimate the heat of reaction of m-p-cresol and isobutylene, and may be compared with the heat calculated by Equation 16. The experimental value a t 183' F. (84"C.) is 642 B.t.u.; the value calculated from Equation 16 is 634 B.t.u. per pound of isobutylene reacting. The excellent agreement between experimental and calculated values is probably coincidental; however, it does lend some faith to the many assumptions made in estimating the heat, both on the basis of test run data and theoretical calculation. In actual practice the reaction is carried out under slightly elevated pressures, and a butane-butene gaseous mixture is used as the alkylating material. Pressure has some effect on the heat capacity of the gases, and the heat capacity is not the same for
July, 1944
.
INDUSTRIAL AND ENGINEERING CHEMISTRY
.
603
Heats of Combustion" K State
. Cal./G. Mole $ii) a t 200 C. (68" F.)
Solid. 732.2 Liquid 735.0 Liquid 882.6 Liquid 880.5 Liquid 882.5 Liquid 1354.5 Liquid 782.3 Liquid 1247.3 Liquid 1400.4 Gas 647.2 Liquid 1252.4 tinospheric pressure and 20' C . , the final of liquid water and gaseous carbon dioxide. mbustion of solid phenol (20" C.) = ,732.2 a t of fusion a t 41' C . = 2.7 (87) ; C P (liquid)
Phenol Pyrocatechol
pounds in Table I.
the mixture of gases as for isobutylene alone; however, since many approximations were used in the above calculations, i t is felt that further corrections to take into account the pressure and composition effects are not warranted. Therefore, it may be assumed that t h e heats of reaction using the commercial gases and pressures are the same as those given above. Further, as noted earlier, the reactions of the mono-tertbutyl derivatives with isobutylene t o form di- and tri-teTtbuty1 derivatives may be assumed t o liberate the same amount of heat as the reaction of isobutylene t o form the mono-tsrtbutyl compounds.
C. S., Bur. Standards, Misc. Pub. 97 (1929). NQ. CHEM., 33, 759 (1941). (11) Ferguson, J. us. Chem., 31, 757 (1927). 8 , H. A., Refiner Natural Gas Mfr., 20, 52
Mulliken, S. P., "Identifications of Pure Ords (Order I)", New York, John Wiley & Sons,
ACKNOWLEDGMENT
Grateful acknowledgment is made for cooperation in compiling the experimental results and constructive criticism given in methods of presentation by W. A. Gruse, D. R. Stevens, and W. E. Hawon, of t h e Mellon Institute, and by t h e many members of both the research and process laboratories of the-Gulf Research and Development Company. BIBLIOGRAPHY
(1) Annual Tables of Physical Constants and Numerical Data, Section 461, page 6, Princeton Univ., 1941. (2) Auwers, K. V., Bundesmann, H., and Wieners, F., Ann., 447, 162-96 (1926). (3) Auwers, K. V., and Mauss, W., Zbid., 460, 240-77 (1928). (4) Bartz, Q. R., Miller, R. F., and Adams, R., J . Am. Chem. Sac., 57,371 (1935). (6) Beattie, J. A., Ingersoll, H. G., and Stock 64, 646 (1942).
(6) Bichowsky, F. R., and Rossini, F. D.,
"
Chemical Substances", New York, Reinhold Pub. Corp., 1936.
(7) Carpenter, M. 8. (to Givaudan-Delawanna, Inc.), U. S. Patent 2,064,885 (Dec. 22, 1936). ( 8 ) Claisen, L., and Eisleb, O., Ann., 401, 21 (1913).
ile, R. L., J.A m . Chem. Soo., 61, 69 (1939J. Tables, Vol. I, pp. 161, 199, 237, New
(21) Nelson, W. (22) Niederl, J. B., IND.
[email protected].,30, 1269 (1938). (23) Niederl, J. B., and Natelson, S., J. A h . Chem. Sac., 53, 272 (1931). (24) Othmer, D. H., IND. ENO.CHEM.,32, 841 (1940). (25) Pauling, L., "Nature of Chemical Bond", Cornel1 Univ. Press, 1942. (26) Perkins, R. P., Dietaler, A. J., and Lundquist, J. T. (to Dow Chemical Co.), U. 8. Patent 1,972,599 (Sept. 4, 1934). Engineers' Handbook, pp. 448 and 477, (27) Perry, J. H New Yor Hill Book Co., 1934. (28) Sandulesco, irard, A., Bull. sac. chim., [4] 47, 1300 (1930). (29) Smith, J. F. D., Tram. Am. Sac. Mech. Engrs., 58, 719 (1936). (30) Stevens, D. R., IND. ENQ.CHEM.,35, 655 (1943). (31) Tchitchibabine, A,, Compt. rend., 198, 1239 (1934). (32) Watson, K. M., and Nelson, E. F., IND.ENQ.CHEM.,25, 880 (1933). (33) Weinrich, Whitney, Ibid., 35, 264 (1943).
Semicommercial Plant for Alkylation of Cresols with Refinery Gases, Showing Storage Tanks Distillation and Alkylation Buildings, and Towers of Refinery Debutenizer in Background
