the solubility of compressed acetylene gas in tetrahydrofura

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The solubilities of compressed acetylene gas in liquids, IV : the
solubility of compressed acetylene gas in tetrahydrofuran
Kiyama, Ryo; Hiraoka, Hiroyuki
The Review of Physical Chemistry of Japan (1956), 26(1): 1-8
1956-08-30
http://hdl.handle.net/2433/46734
Right
Type
Textversion
Departmental Bulletin Paper
publisher
Kyoto University
The
Review
of Physical
Chemistry
of Japan
Vol. 26 No.
1 (1956)
THE SOLUBILITIES OF COMPRESSEfl ACETYLENE GAS
IN LIQUIDS, IV
The Solubility of Compressed Acekylene Gas in Tetrahydrofuran*
HY RYOKIYAMA
ANDIlIROYUKI
HIRAOKA
Inkroduckion
In the previous papers, the authors reported the solubilitiesof compressed acetylene
gas in wa±er'>,methanol-' and benzene' and found that the solubility of acetylene in
water at lugh pressures devia*.esnega±ively from Henry's law in the from N,=kP,
where N: is the mole fraction of acetylene, P the partial pressure of acetylene and
k a constant and the solubility is nearly proportional to the fugaci[y of acetylene,
while the solubiHtiesin methanol and in benzene a± high pressures deviate positively
from Henry's law and moreover the solution of benzene shows the positive deviation
from Raoult's larv and this deviation cottld be well explained on the basis of the
theory of regular solutions with the Flory-Huggins entropy correction arising from
the difference in the nrolal volumes of the two substances. In the present paper,
the solubility of acetylene in tetrahydrofuranhaving an electronegative oxygen atom
in the molecule, a donor solvent for acetylene, in the range of temperature from 0
to 30°C and up to pressure 30 kg/cm', which has been never measured, is reported
and rather qualitative considerations upon the characteristics of acetylene solutions
are given.
I
Experimentals
Tetrahydrofuran used as the solvent is fractionated by distillation, after refluxing
with metallic sodium for several hours and a portion with boiling point 66.166.3°C
(760mmHg) is taken, and its vapor pressure measured with an isoteniscope in the
range of60 to 760mmHg and its density from 5 to 30°Care represented by Eqs. (1)
and (2), respectively,
dr=0.9079-9.93x10-"t-1.6x10-et
(1)
loge Pr=-1022x10-'+,5.635
.t+2~5
,
(2)
where P, is in mmHg and t ~indegrees centigrade.
` This incesiigation
lrasbeendare by A. Itraoka, beingin fhe postgraduate
course,underthe
direcfiouof Prof.R. lcyarna.
1) H. Hiraoka,Thisjournal,24, 13 (1954)
2) R. Kiyamaand H. Hiraoka,ibid., 25, 16 (1955)
3) R. Kiyamaand H. H'vaoka,ibid., 25, 52 (1955)
i
The
2
Review
of Physical
Chemistry
of Japan
1 (1956)
Vol. 26 No.
R. Kiyama and H. Hiraoka
Acetylene
used as the solute and the experimental
measurements
are all the same
as those described
procedures
in the previous
for the
present
reports.
Resultr
The vapor pressure
and density
of tetrahydrofuran
the calculation of the solubility are represented
of dilatation by the absorption
the same valve
the difference
solvents
of acetylene
as in acetone'I
among
because
the values
are like one another,*
at each temperature
used in
by Eqs. (1) and (2) and the coefficients
in tetrahydrofuran
the data
in the other
in tetrahydrofuran
solvents
and the correction
are assumed
are lacking and
is comparatively
of the solubility
to have
small if the
due to the dilata+ion
is small.
Table 1
Solubility of acetylene in tetrahydrofuran
at one atmosphere
Temperature,
°C
Bunsen's coeH.
5
10
15
?0
25
The solubility
given in Table
of acetylene
30.1
26.0
22.0
19.5
17.3
in tetrahydrofuran
1 and represented
at one
N_ denotes
In Tables
the mole fraction
Table
i
of acetylene
2 and 3, the solubility ofcompressed
is given in the mole fraction
2
pressure
is
by Eq. (3),
log,°
N_=8.85~x
10'_4.155
where
atmospheric
of acetylene
and T the absolute
acetylene
and the numbers
Solubility of zcetylene
(3)
temperature.
gas in tetrahydrofuran
of cc of acetylene
(S. T. P.)
in tetrahydrofuran
(mole fraction of acetylene, N_)
Temp.
Press.,
°C
0
10
20
30
5
U.341
0.237
0.231
0.192
10
0.519
0.439
0.369
0.323
0.491
0.433
0.595
0.532
0.704
0.613
kglcmp
15
I
?0
S
s
acetylene
4)
0.691
This will be confirmed in [he following paper in which tbe partial
in various solvents will be reported.
J. Horiuti, Sri. Posers Inst. Phys. Citem, Resemch, Tokyo, ]7. 125 (1931)
molal
volumes
of
The
The Solubilities
Table
3
oI Compressed
Solubility
Temp.,
Review
of Physical
Chemistry
Acetylene Gas in Liquids,
of acetylene
of Japan
Vol. 26 No.
IV
3
in tetrahydtofuran
°C
a
~.a
1~
112
296
217
Press., kg/cm=
5
10
~.~
15
617
20
25
o.~
64~
~~
129
264
207
402
307
649
929
25kB'°"
i.e
zOk
to C
os
15k8/~^'
i
~~
L6
10
1A
ykflj
'C
TN
n O.a
O
C
20'C
2`
s
oa
i2
C
0g
~
1.0
~a~`
0.7
~.8
0
5
10
15
2(1
Partial p¢ssurc of acetykoa kg/cm'
33
Fig. L Solubility of acetylene in tetrahydrofuran as function of partial pressure
of acetylene
contained
fraction
that
in
solubility
N.,=kP
logarithm
of
temperature
gation.
has
of
of acetylene
the
form
1 cc
been
made
is plotted
at
high
and
Fig.
the
mole
at
The
tetrahydrofuran,
each
of
of
Dalton's
gaseous
phase
calcular_ed
is described
later-
the
linear
and
according
the
the
to the
method
1,
from
in
which
fraction
partial
of
developed
of
the
mole
it is observed
Henry's
law
exists
between
reciprocal
range
to the
mole
Fig.
relationship
the
temperature
pressure
and
3.6
of acetylene,
negatively
acetylene
total
law,
In
a nearly
within
35
I /T ~10'
Logarithm of mole fraction of acetylene
ploited against reciprocal of absolute
temperature
thepartialpressure
deviates
that
pressure
conversion
using
against
fraction
Fig. 2
respectively.
pressures
2 shows
3A
of
the
the
present
pressure
tetrahydrofuran
by Robin
in the
the
absolute
investi-
of acetylene
in the
of nl., which
1 (1956)
V
The
4
Review
of Physical
Chemistry
1 (1956)
of Japan
Vol. 26 No.
in water,
methanol,
R. Ki}ama and H. Hiraolsa
Considerations
The
benzene
authors
have
measured
and tetrahydrofuran
view of the
effect
of the
the
and these
partial
the solubility at high pressures
the case in whichthe
in benzene
latter,
belong
as is seen
against
solubility
in water
and
solubility
the
solubilities
pressure
deviates
nonpolar
to the former
positively
Fig. 3 in which the
pressure
of .acetylene.
is exceptionally
donor
solvents
mole fraction
or in water
that
belongs
the
mole
fraction
highest
when the
in
and the
is plotted
that the
of acetylene
those in these
in water
of acetylene
and
to the
it is notable
to the fugacity
among
other
in methanol
of acetylene
case.
of acetylene
solubility
to the former
to the latter,
law
and in tetrahydrofuran
In the latter
is the
into two cases
One is the case in which
The solubilities
low and proportional
in tetrahydrofuran
in general
classified
from Henry's
and those in water
It may be considered
solvents
aze
of acetylene.
used and fifty times as high as the mole fraction
20 kg/cm=.
of acetylene
solubility :deviates negatively.
from
the. partial
solubilities
solvents
at 20°C and
in alcohol
or in
and the solubility of acetylene
solubility
is represented
in
by the
of acetylene.
0-~
hfethanol
os
TecrahYdMfuran
0.5
Water
ti
2 OS
~_os
y
Bemene
Y
bT Q
Q
Pamrene
`
o
=' 0.4
`
c
.~03
<`
Sfethanol
Tetrahvdrofuran
0.2
Wafer
os
io
t;
zo
zs
an
partialDressure
of acetylene:
kgrem'
Fig. 3 Solubility of acetylene as function of
partial pressure of acetylene at ~°C
Now, pure
chosen
as the standard
acetylene
ratio
liquid acetylene
of the
fugacity
The futLacity of pure
L
state
in the liquid solution
in equilibrium
of acetylene
in equi]ibrium
of acetylene
acetylene
in the
is already
o
oz
o.a
ob
oa
h7olefranionof acetykne..h4
Fig. 4. Activity of acetylene plotted against
mole fraction of acetylene at 20°C
with its vapor
at each temperature
in the liquid solution, then the activity
with the gaseous
soluton
reported
is
of
phase is equal to the
[o that in the pure liquid state.
and
the
concentration
of the
J
The
Review
of Physical
Chemistry
of Japan
The SolubIli[iesof Compressed AcetyleneGas in Liquids, IV
Vol. 26 No.
1 (1956)
5
liquid solvent in the gaseous phase necessary to the calculation of the fugacity of
acetylene in solutions is assumed to be approximately computed by Eq. (4) according
to Robin et al.~,
log~n ~-(A+131T)P
°
(4)
where m is the mass of the liquid solvent per 1 cc of the gaseous phase of density
p in Amagat unit and ara° the mass of the liquid solvent contained in 1 cc of the
gaseous phase in the absence of the compressed gas. The constants in Ey. (4) are
shown in the table.
System
acetylene-water
acetylene-methanol
acetylene-benzene
acetylene-tetrahydrofuran
A
-0.00187
-0.00234
-0.00544
0.00160
A
2.45
2.01
5.75
I
~
In [he last system, acetylene-tetrahydrofuran. the first term A on the right hand
side of Eq. (4) contains only the contribution by the Poynting effect, and the second
term is taken into no account because the appropriate physical constants of Letrahydrofuran necessary to the calculation are unavailable. Then the fugacity of acetylene
in solutions in equilibrium with the gaseous phase is calculated as an approximation
using Lewis-Randall's law, f =f_°N_, where. f., is the fugacity of acetylene in the
solution and f_° the fugacity in the pure state. 1'he difference between the value of
the fugacity thus obtained and the value under the assumption that the gaseous phase
is pure acetylene is considerable at high temperatures and low pressures, but the
difference is only slight at low temperatures and high pressures.
Fig. 4, in which the activity of acetylene in each solution at 20°(; is plotted against
the mole fraction of acetylene, shows [hat the positive deviations from Raoult's law
are found in the soiution of acetylene in water, methanol and benzene, whereas the
negative deviation in the solution of acetylene in tetrahydrofuran,
In the discussion
of the solutions of compressed gases, the change of free energy or activity with
pressure mus*_be taken into account and this change is related by the well known
thermodynamic equa~Son to the partial molal volume of the solute in solutions. In
the following paper the authors will report on the measurements of the partial
molal volume of acetylene in the wide range of concentration in the various solvents.
So, in the present paper qualitative considerations about the characteristics of
acetylene solutions may be rather given in the following.
Acetylene-toater system
As mentioned previously, the solutions of acetylene in wa*.er, alcohol and nonpolar
solvents, such as benzene, deviate positively from Raoult's law. Among t4zm, aqueous
5) S. Robin et B. Vodar, J. Fhys. e! Fad.,.13, 264 (1952)
i
i
The
6
Review
of Physical
Chemistry
of Japan
Vol. 26 No.
R. Kiyama and H. Hiraoka
solution
shows
the . activity
with
each
the lazgest
against
other
positive
the mole
but
the
deviation
fraction
activity
and
Fig. 5 indicates
at 20°C and
30°C are
at a low temperature
that
Imear
gradually
the isotherms
and
nearly
decreases
of
coincide
from
the
37 K 3UC
O.fi v
temperature
_T
1°C
10°C
o Q4
T
20°C
0
30°C
G
i
.~
os
1'C
~a~i
0
OAW
OA10
0.015
0~2D
ttolo fraztionof acetylene,,~,
Fig. 5 Activity of acetylene in water plotted against
mole fraction of acetylene
values at 20°C and 30°C,
water is negative,
These indicate that the heat of sohttion of liquid acetylene
that is, exothermic
has a lazge negative
value.
and the excess partial
molal entropy
The assumption°I• ~1 that the rare gases
in
of solution
and hydrocarbon
gases form "iceberg"
when they dissolve in cold water and that those molecules in
solution may be surrounded
by oriented cages of water molecules, gives a fine interpretation for the characteristics
of aqueous solution of acetylene
and
that the isotherms at temperatures
higher than the critical temperature
of acetylene,
which is obtained
and that of the gas hydrate
the isotherms
supposed
partial
to be large
Acetylene-metlrauol
and is equal to 16°C°~, would
molal
are drawn
heat
capacity
of acetylene
neazly coincide,
lower with decreasing
of acetylene
whereas
temperatures
in aqueous
solution
is
at lower temperatures.
system
Acetylene•methanol
result of various
pressures
difference
from the cross point of the vapor pressure
at lower temperatures
and from this the
it is ohserved
of the hydrate
factor,
system shows a positive deviation
the
association
of methanol,
the
from Raoult's law, as a net
difference
in the internal
of the two substances,
the interaction
of methanol
and acetylene, the
in the molal volumes of the two substances and so on. The temperature
6) H. S. Frank and M. N. Evans, J. Chem.Phys., 13, 507 (19x5)
7) W. F. Clauesen and M. F. Polglase, J. Am. Chem. Soc., 74, 9817 (1952)
8) M. V. Stackelberg and H. R. Muller, Zeit. Efectrachemie, 58, 25 (1954)
1 (1956)
a
The
The Solubilities
coefficient
so that
of the
the
activity
Mcintosh's
and
alcohol
benzene
at lots
is, endothermic
of
solution
condensation
is
positive,
in methanol
of Japan
Vol. 26 No.
1V
as
from
the
heat
gaseous
of
to other
the
from
of
the
temperature
of
solution
gas.
It
solutions
in
may
Raoult's
shown
in Fig. 6,
in accordance
compound
of acetylene
be
of
this
deviation
and
with
of
molal
the
acetylene
of regular
benzene
solution
solutions
in the
liquid
theory
of acetylene
the
law
regular
coefficient
of
tvi*1t the
acetylene
that
differences
is of
considered
activity
of
in benzene
course
could
of the
be
two
acetylene
is positive,
although
exothermic
this
in
Flory•Huggins
volumes
solutions,
that
in nonpolar
the
acetylene
the
owing
is
that
heat
to the
interpretation
may
be
solvents.
%'
0
P/
os
so
~~
.•~/
as
as
~r:
~/
ad
0
OA
OA
s
~.;
.'T
0
:'~
0'C
02
Acetone
02
Mok fraMionof aoetykoe. N
0
Fig. 6
02
Activity
against
OA
of acetylene
mole
fraction
Ob
in methanol
solutim
at 3C
Mole (racoon of acetylene, N.
OS
0
plotted
Fig. 7
of acety]ene
02
OA
0.6
•
x
0°C
10°C
•
x
temperature
0°C
]0°C
p
O
ZO°C
30°C
~
O
20°C
30°C
D. Mcintosh, j. Phys. Chem., 11, 306 (1907)
OB
Activity of acetylene in tetrahydrofuran
plotted against mole fraction of acetylene
temperature
9)
1 (1956)
7
is negative
of a crystalline
reported
theory
in accordance
of
applicable
the
arising
the
authors
deviation
of
Moreover
so that
the
positive
basis
corrections
negative,
acetylene
of the formation
paper,
a
on the
substances.
Gas in Liquids,
in methanol
of liquid
Chemistry
sysfe»z
shows
entropy
Acetylene
of Physical
temperatures.
previous
explained
acetylene
observation's
Acetylene-benzene
In the
of
hear_ of soluraon
with
of Compressed
Review
i
I
The
S
Review
of Physical
Chemistry
of Japan
Vol. 26 No.
R. Kiyama and H. Hiraoka
Acetylene•tetrahydrafiaran
Tetrahydrofuran
molecule
sys[en:
has an electronegazive
which has electrons
the proton
of acetylene.
having an active center
that are
Studies
oxygen
available
atom in the carbon
for
hydrogen
on the solubilityof
acetylene
have been made extensively
bond
chain of the
formation
with
in such a donor solvent
from the technical
point of view,
but those under high pressures
are comparatively
few. 1'he solubility of acetylene
in acetone measm~ed by Holemann ei a1,.10>changes in the same manner as in tetrahydrofuran
with pressure.
Fig. 7, in which the activity of acetylene
acetylene,
acetylene
obtained
activity
shows
that
in tetrahydrofttran
from
the
data
of acetylene
tion between
by Holemann
of hydrogen
The authors
for the Fundamental
against
Raoult's
the
than that in the
indicating
that is, exothermic
solvent
molecule
bond formation
mole
fraction
solution
of acetone
coefficients
and the strong specific interacmay be expected
between
in accordance
the electronegative
atom
of acetylene.
has been done by Mr. N. Yoshida.
to the Department
Scientific Individual
Research
of Education
for the
Grant
(1'he Yhysico-Chemical
The Laboratory
of Physical
Kyoto University
and R. Ilasselmann.
of the
that the heats of solution
Clrem. ing. Teclmik, 25, 4ti6 (1953)
in Aid
Researches
on Acetylene).
1D) P. Holemann
of
law in the solution of
e! al. and the temperature
measurements
are indebted
smaller
are positive,
in the donor solvent and the proton
Part of the present
I
is slightly
and donor
is plotted
de~~ation from
are negative,
acetylene
with the assumption
negative
in both solvents
in such donor solvents
i
the
Chemistry,
1 (1956)
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