Experimental solid-liquid equilibria of binary mixtures of organic compounds

265

Fluid Phase Equilibria, 29 (1986) 265-272 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands

EXPERIMENTAL

SOLID-LIQUID

EQUILIBRIA

OF BINARY

MIXTURES

OF

ORGANIC

COMPOUNIIS

P.C.

PROUST

Escuela

de

and

J.C.

FEHNANDEZ

Ingenieria

Valparaiso,

Quimica,

Universidad

Catllica

de

Valparaiso,

Chile.

ABSTRACT A

simple

which organic

cell

heated

or

through with

down

cooled

immersed

last

in

the

of

Systems

known is

stirred

from The

cell.

of

(

binary

a magnetic

bar,

a t.hermostated

temperature

is

jresolution:

3re

system monitored

0.01

E),

which

mixture. are

a rate

melted,

of

rise

of

include o-xylene

in

the

this

and

rate

occurs,

When which

temperature. ni trobenzene

of

p-xylene,

and

K/min.

0.06

equilibrium

mixtures and

acetone

crystallized,

partially

approximately

a sharp

determination

i-octane,

with

methanol the

at

solubility

C.

composition

Z-butanone,

n-heptane,

solid

0 p e r a t Pd

and

constructed

the

thermometer

investigated

methanol, with

35

solid-liquid

precise

been of

circulating

heated

crystal the

-

surrounding

carefully

allows

to

resistance

Solutions

has

vigorously

by

a jacket

then

cell

determination

content.s,

a platinum

the

reliable the

mixtures

The

is

and

permits

and

of

with

n-butyric

acid

2-butanone.

INTRODUCTION Solution

models

determination the

of

means

to

thermodynamic In

data

binary

measurements

if

needed of

has

parameters,

quite been

predictions

037%3612/86/$03.50

on

the

precise

which

provide

parameters

often

shown

through

which given

to

range

for set

the

the

UNIFAC

0 1986 Elsevier Science Publishers B.V.

VLE phase

results. of

et

1975)) from

other

inadequate

departs

generated

predicting al.,

obtained

parameters

(Magnussen

by

for et

mostly

a different

temperature data

are lead

that

equations

(Fredenslund

those

equilibria the

original

UNIFAC

considered apply

liquid-liquid the

depend

equilibria, model

parameters

to

situations for

use,

phase

necessary

popular

are

Similarly,when that

the

interaction

it

current of

reduction.

. Efforts

equilibrium example,

in

kinds the

coefficients the

are

obtain

particular,

activity then

which

different

al.,

For

parameters

is

1981).

substantially binary model

from

interaction do

not

always

well

compare

with

systems

(Gmehling

Thus,

if

rapid

of

many of

cited

to

be

happens

Bernini,

with

the

organic

1983). are

region,

the

equilibrium

critically

needed

to

precise

and

conditions

must

that

amount

studied,

in

information 1928;

(Washburn,

are

still

required,

binary

very

for

Land01

matrix.

to

Also,

the

measurements

old

t-

especially

parameter

some

mind,

based

(1980),

experimental

which

revised.

cell,

reasonable

data

UNIFAC contain

goals

equilibrium

of exist

more the

above

these

Collins

it

multicomponent

parameters

solid-liquid

equilibria

totality

references With

and

interaction

tabulat.ions

phase

1964),

the

Carta

and

low-temperature

the

extensive

B6rnstein,

need

of

binary

realized.

type

cover

1978; the

as

values,

many

numerous

into

determination

Al though

he

al.,

and

model

practically

this

experimental of

et

valid

this

extend he

the

equilihria

solid-liquid

can

of

have

a design

give

accurate

from

developed and

down

to

by

K.

3 cm

in

and

results

K temperature 238

simple

Marzzacco

reproducible

a 50

ambient

very

3

presented

Presently,

time.

extending

we

on

in

range

can

EXPERIMENTAL AJS?ar_at!S The glass

cell

total

of

volume

the

nitrogen

rubber and

the

with

The

cm into

a magnetic cell

is

mixtures. from

a

The

inner

in

order

magnetic

Instrulab

cell

OmniScribe Dry Figure equilibrium

allow

The

the

a perforated thermometer contents

are

the

the

is

visual

or

under

methanol

it

rate

of whole

is

accuracy can

The

joint, vacuum

and

of

the

observation

a control

empty, cell.

a ground-glass

one

cold

with

left

of

outer

passage,

regulate to

has

a

exhaust

heat

circulated of

be

0.05

filled

transfer

K. with

from

assembly

rests

the over

a

stirrer.

sensitivity

solutions,

to

methanol

cell

with to

resistance

means The

to

be

serves

inserted.

placed,by

middle

can

diameter,

tube

bar.

thermostat,

jacket

circulating An

the

The

platinum

are

vessel.

refrigerated

methanol,

cell. the

tube

insulation

Through

and

protruding

the

spin

a triple-jacketed thermal

length

which

entrance

equilibrium

provides

in

a short

through

nitrogen

inside

20 mL;

admitted

stopper,

stirred

the

is 130

of

model 0.01

4000

K is

contents.

The

digital

used;

resistance its

thermometer

probe

thermometer, is

output

in

is

direct

also

with

contact

fed

to

a with

a Houston

recorder’. nitrogen thus 1

gas

is

preventing shows

apparatus.

a

used

to

moisture schematic

flush

the

air

condensation drawing

space into

of

the

over

the

liquid.

solid-liquid

the

267

cell

The solution

known

above

space cell Typical

solution 1

mixture. increases the

When

the

last

because

only

crystal

sensible

time-temperature two

equilibrium

being

accuracy

checked

of

against

the

final

melting

of

pure

the by

t.emperature rate),

break

extrapolation

solution or

in

the

of

the

determines

the

charged

three

times to

thermometer

point

of

monitored

This

reproducible

resistance

setting

original

melting) two

is

temperature

of

the

the

repeated

consistently the

rate

the of

by that

as

supplied.

distinct;

t he

stopwatch.

double

being

after

are

K/min,

digital

air

and

appears.

the

and

the

least

temperature

measurements

results

The

very

solid

1 K above

0.06 a

The

crystalized.

heated,

melt

about

now

and

solid-liquid

solution,

to

at

is

is

(before

These

cell.

heat

the

b innry

a

Cooling

ially

carefully

disappears, (to

curve

branches

before

with

of

nitrogen,

part

methanol

of

mL

vessel.

is

then

further

sharply

dry

transfer

begins

rate

checked

rises

is

circulating

a constant and

heat

6 K occurs

phase

solid

at

recorder

increase

the

w.ith

components

mixture of

The

the

2 to

of

heterogeneous

temperature

the

of

the

50

gravimetrically.

displaced

inside

one

subcooling

The

approximately prepared

is

placed

unti

provided,

with

composition,

the

then

is

charged

is

of

in fot

within was

the each

0.02

K.

frequently

ice.

RESULTS First, acet

a comparison

ir

the

behavior

with

an

the

of

complete

1928) in

the

solubility following

n-Butyric Results

systems

are

n-butyric

shown yet

for available

It parameters

in

Figure

calculated

is

the

2-butanone,

last for

evident obtained

three the

the

n-butyric plotted

the

systems;

no

from

these VLE data

1.60

work, branch

K occur.

:

and and

p-xylene 2-butanone I

and

2,

acid-n-heptane in

Figure chap.

and

3.

equations

interaction

reduction

former

Tables

1969,

figures

that Tables

nitrobenzene-p-xylene

UNIFAC

(Prausnitz,

nitrobenzene-methanol from

in

are

with

to

acetone

2,

noted

investigated

o-xylene

and

well,

acid-rich

up

listed

are

be

the

the

verify

spanning

Critical of

then

systems

relationships

must

acetic of

were

nitrobenzene-methanol

plotted

Solubilities

differences

systems

acid-2-butanone

thermodynamic

those the

for to

solutions

It

n-heptane,i-octane,

these the

in

systems

methanol,

with

from

al.

order extremely

nine K.

et

in

International

and

where binary

with acid

respectively;

point

curve, eight

for

0.07

the

Tan

agree

, for

of in

of

1952),

results

considerably

eutectic

Nitrobenzene

*

Our

range,

data

al.,

deviation

listed

depart

the

the

et

apparatus.

composition

(Washburn,

with

(Tan

temperature

especially

*

the

determinations

The

made

system

average

earlier

of

was

acid-benzene

and 9)

usual

are

also

parameters

system. that

binary (Gmehling

interaction et

a1.,1982)

are

268 are

inadequate

binary are

predict

to

apparently

systems,

the

equilibria

solid-liquid

when

large

of

some

extrapolations

temperature

involved. Analytical-grade

greater

than

additionally

%.

dried

The

Nitrobenzene

following overall

estimated

temperature:

were

reagents 99.5

0.04

nitrogen

K

with

used, and

the

recommended accuracy

, composition:

two

certified xylene

of

the

0.0005

results

mole

we

inner

jacket

methanol

methanol

-

liquid

level

-

spin

-

in B

Solid-liquid

out

_

1 1.

probe

, .

r

Figure

are:

report

fraction.

thermometer

in

jacket-

were

procedures.

nitrogen evacuated

purities isomers

equilibrium

apparatus.

bar

out

269

TABLE 1. Solid-liquid equilibria of binary ( Nitrobenzene = component 2 )

systems

with nitrobenzene.

_______.______.__.____.____.___..____.__ ._ ._ ..._.._ ___ _-.. .._...__ -_--_-..-_-. x(l) 0.0000

0.0263 0.0512 0.0975 0.1501 0.2011 0.2499 0.3007 0.3502 0.3995 0.4520 0.4980 0.5512 0.5980 0.6274 0.6568 0.6785 0.7022 0.7267 0.7500 0.7759 0.8010 0.8257 0.8511 0.8751 0.9004 0.9195 0.9404 0.9553

T, C 5.64 4.46 3.56 2.44 1.53 0.91 0.32 - 0.11 - 0.52 - 0.90 - 1.35 - 1.69 - 2.17 - 2.51 - 2.83 - 3.14 - 3.48 - 3.80 - 4.21 - 4.69 -- 5.36 - 6.09 - 7.13 - 8.71 -10.68 -13.61 -17.08 -23.24 -29.78

SZXYkE!?

x(l) 0.0000

0.0501 0.1002 0.1546 0.2006 0.2535 0.3008 0.3500 0.4008 0.4518 0.5003 0.5510 0.5519 0.5707 0.8700 0.9000 0.9242 0.9494 1.0000

T, C 5.64 2.95 0.23 - 2.50 .- 4.96 - 7.70 -10.42 -13.15 -16.14 -19.24 -22.49 -26.02 -26.17 -27.52 -29.70 -28.66 -27.85 -27.01 -25.19

X(l) 0.0000

0.0258 0.0487 0.0505 0.1010 0.1510 0.2036 0.2513 0.3033 0.3511 0.4002 0.4512 0.4984 0.5002 0.5251 0.5505 0.5754

5.ti4 4.29 3.01 2.97 0.15 - 2.64 - 5.67 - 8.52 -11.77 -14.92 .-18.35 -22.23 -26.32 -26.44 -28.52 -30.52 -33.21

pzzylene ---x(l) T, C 5.64 0.0000 0.0508 2.96 0.1000 0.39 0.1508 - 2.15 0.2006 - 4.69 0.2507 - 7.30 -- 9.95 0.3009 0.3497 -12.57 0.3653 -13.45 -13.93 0.3762 0.3827 -13.13 0.3890 -12.75 0.3979 -12.03 0.4489 - 9.10 0.4989 - 6.53 0.5499 - 4.02 0.5994 - 1.83 0.22 0.6484 0.6978 2.23 0.7478 4.13 0.7964 5.91 0.8474 7.74 0.8978 9.35 0.9473 11.16 0.9721 12.04 1.0000 13.14

TABLE 2. Solid-liquid ( n-Butyric

xii)

equilibria of binary acid = component 2 )

n:Heptane ----

0.0060 0.0516 0.1009 0.1515 0.2023 0.2514 0.3010 0.3504 0.4017 0.4509 0.5018 0.5504 0.6004 0.6488 O.F992 0.7499 0.7805 0.7990

T. C -- 5.34 - 7.62 - 9.85 -11.72 -13.39 -14.86 -16.28 -17.53 -18.89 -20.10 -21.66 -23.00 -24.49 -26. OS -27.98 -30.33 --31.79 -32.96

El!utaer?es x(l) T, 0.0000 0.0515 0.1020 0.1497 0.2025 0.2529 0.3028 0.3512 0.4040 0.4519 0.4741 0.5022

- 5.34 - 7.90 -10.32 -12.67 -15.33 -17.94 -20.70 -23.48 -26.71 -29.88 -31.37 -33.41

C

x(l)

i-Octane .--_-----

0.0000 0.0406 0.1011 0.1517 0.2013 0.2512 0.3016 0.3506 0.4011 0.4513 0.5012 0.5516 0.607Y 0.6513 0.6995 0.7503 0.7605

systems

T. C - 5.34 - 7.35 - 9.92 -11.76 -13.42 -14.99 -16.39 -17.80 -19.11 -20.56 -21.87 -23.45 -25.31 -26.77 -28.64 -31.05 -32.69

with

n-butyric

xi11

acid.

Acetone ---..--__

o.Oobo 0.0619 0.1001 0.1544 0.2045 0.2502 0.3038 0.3500 0.4027 0.4504 0.5013 0.5185

T.

-.

C

5. 34

- 8.31 -10.10 -12.64 -15.06 -17.37 -20.14 -22.72 -25.78 -26.80 -32. 26 -33.56

271

methanol

l

-24.

-

0

p-x+na UNIFAC

.

\

\

\

_3J---,ided, ‘),, , rolyhility

0.2

0

Figure

2.

Solid-liquid

nitrobenzenr-p-xylene

equilibria

0.8

0.6 fraction

of the nitrobenzene-methanol

and

systems.

-

0

0.4 solvent mole

, , ,.

UNIFAC

0.2 solvent

0.4 mole

0.6 fraction

Figure 3. Solid-liquid equilibria of the n-butyric and n-butyric acid-2-butanone systems

acid-n-heptane

212 ACKNOWLEDGEMENTS We acknowledge de Desarrollo General

financial

Cientifico

de Investigacibn,

Calculations

organic

Fredenslund,

R.L.

by the Fondo

(Chile) Cat6lica

by Ignacio

de Valparaiso.

of solid

J. Chem. Eng. Data,

Jones

and J.M.

J.G.,T.F.

equilibria

using

Anderson UNIFAC.

Prausnitz,

and J.M. Prausnitz, tnd. Eng. Chem.

acetic

acid

in

28: 328-330.

contribution estimation of activity coefficients liquid mixtures. AIChE Journal, 21: 1086-1098. Gmehling,

National

and by the Direccibn

Olaeta.

1983. Solubility

solvents.

Aa.,

provided

Universidad

were performed

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y Tecnolbgico

1975. Groupin nonideal

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Des. Dev.,

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K.A.

Krieger

Englewood

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NJ.

and J.G. Miller,

acetic acid in the acetic Sot., 74: 6181--6283.

1952. The polymorphism of acid-benzene system. J. Amer.

E.W. (editor), 1928. "InternBtional Critical Tables Physics Chemistry BBd Technology", Vol.IV, !%!nri9_al Da&a, -- ----L ---__--108, McGraw-Hill, New York.

pf p.