-
8/11/2019 US3996298.pdf
1/9
United
States Patent [ 1 9 ]
[ 1 1 ]
3 , 9 9 6 , 2 9 8
Izumi
e t
a l . [ 4 5 ] D e c . 7 , 1976
[54]
PROCESS
FOR
THE HYDRATION
OF 2 , 8 7 6 , 2 6 6
3 / 1 9 5 9
Wegner . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 6 0 / 6 4 1
()LEFINS
3,758,615
9/1973
Izumi e t a l . . . . . . . . . . . . . . . . . . . . . . .
. . 260/641
[ 7 5 ] .
I n v e n t o r s :
Yusuke
I z u m i ,
S h i n n a n y o ;
Sumio
FOREIGN PATENTS
OR
APPLICATIONS
A k iy a m a , Tokuyama; Kinya
. . 4
Y a m a z a k i , Y o n o ; Ma s a t o Todo;
486,783
6/1938 U n i t e d Kingdom . . . . . . . . . . . . . 2 6 0 /
6
1
Takao T o m i t a , b o t h o f Tokuyama, OTHER PUBLICATIONS
3
o f
J a p a n K a i s e r e t a l . ,
I . &
. C .
P r o d u c t R & , v o l . 1 , D e c .
[ 7 3 ] A s s i g n e e : Tokuyama
Soda K a b u s h i k i
K a i s h a , 1 9 6 2 ,
R e p r i n t , p p .
2 9 6 4 3 0 1 .
J a p a n
[ 2 2 ]
F i l e d ; N o v _ 1 , 1 9 7 4 P r i m a r y
Examiner-Joseph
E . E v a n s
A t t o r n e y ,
A g e n t , o r
F rm-Sherman &
h a l l o w a y
[ 2 1 ]
Appl.
N o . : 520,094
R e l a t e d
U S. A p p l i c a t i o n D a t a [ 5 7 ]
ABSTRACT
63 C _ _ A rocess for the preparation of m o n o h yd ri c
alcohols
[ 1 2 1 5 3 ; 2 1 2 : 2 5 0 o f 8 6 f
N 0
2 3 8 1 2 9 M a r c h
2 7 1 9 7 2 b y c o n t a c t i n g
a
m o n o o l e f i n o f 2 - 4
c a r b o n
a t o m s
w i t h
an aqueous
s o l u t i o n containing a
heteropo1yacid
i o n ,
[ 3 0 ]
F o r e i g n
A p p l i c a t i o n
P r i o r i t y D a t a t h e r e b y s u b j e c t i n g t h e
o l e f i n t o a
h y d r a t i o n
r e a c t i o n ,
May
1 1 9 7 1
Japan
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4 6 4
8 7 2 0
characterized i n t h a t
s a i d
a q u e o u s
s o l u t i o n
contains
the
heteropoly-acid i o n i n a
concentration
of a t l e a s t
[ 5 2 ]
U S .
C l ; . . . . . . . . . . . . . . . . . . . . . . . . . .
2 6 0 / 6 4 1 ;
2 5 2 / 4 1 1 R IMOOOO mol
p e r l i t e r
and h a s a PH a n g i n g from 2 ' 0 t o
[ 5 1 ] I n t . C l . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . C07C 29/04 4 5
and t h e
aqueous
S o l u t i o n
i s heated
t o
a tempera_
[ 5 8 ]
F l e l d
o f Search
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . 260/641
t u r e
s u f f i c i e n t l y
h i g h
f o r
i n i t i a t i n g
t h e
h y d r a t i o n
r e a c _
[ 5 6 ]
R e f e r e n c e s
C i t e d t i o n , w h i l e
t h e f r e e i r o n i o n
c o n c e n t r a t i o n
t h e r e i n i s
m a i n t a i n e d a t n o t h i g h e r
t h a n 1 0 p p m
s u b s t a n t i a l l y
. UNITED STATES PATENTS
t h r o u g h o u t
t h e
whole h y d r a t i o n r e a c t i o n
p e r i o d .
2 ,162 ,913 6 / 1 9 3 9
Eversole
et a l . . . . . . . . . . . . . . . . . . . . 2 6 0 / 6 4 1
2 173 187
9/1939
Tanner
. . . . . . . . . . . . . . . . 1 . . . .. 260/641
2 , 5 7 9 , 6 0 1 1 2 / 1 9 5 1 N e l s o n
e t
a l . . . . . . . . . . . . . . . . . . . .
2 6 0 / 6 4 1 4 Claims,
2 Drawing Figures
2
Q
1 L
8
A
O
o . o \
2V
0 IO
U
0
L L ]
C )
O
( f )
l
O: 5
( f )
> _
O
a
< I
U
o
o l o
-
8/11/2019 US3996298.pdf
2/9
3 , 9 9 6 , 2 9 8
e c .
7 ,
1 9 7 6
8 . P a t e n t
l 5
0 /
/
m
/
. a
/
F
.
O
_.
n l u
? \ Lr r / m
F e I O N ( p p m )
F i g .
2
I l
-
8/11/2019 US3996298.pdf
3/9
3 , 9 9 6 , 2 9 8
1
PROCESS
FORTHE H Y D R A T I O N OF O L E F I N S
T h i s i s
a
c o n t i n u a t i o n o f
a p p l i c a t i o n S e r . No.
2 3 8 , 1 2 9 ,
? l e d M a r .
2 7 ,
1972 n o w a b a n d o n e d .
T h i s i n v e n t i o n
r e l a t e s t o
a p r o c e s s f o r t h e h y d r a t i o n
o f
o l e ? n s , w h i c h c o m p r i s e s h y d r a t i n g a n
o l e ? n b y c o n
t a c t i n g i t w i t h
an
aqueous s o l u t i o n c o n t a i n i n g
a
h e t e r o p o l y - a c i d
i o n a s
t h e c a t a l y s t , r e c o v e r i n g a l c o h o l
from t h e r e s u l t i n g
a q u e o u s
s o l u t i o n o f t h e c o r r e s p o n d
i n g a l c o h o l , a n d r e c y c l i n g t h e
a q u e o u s
s o l u t i o n c o n
t a i n i n g t h e
h e t e r o p o l y a c i d
i o n r e m a i n i n g a f t e r t h e r e
moval o f a l c o h o l t o
t h e h y d r a t i o n
s t e p t o
u s e
i t
a g a i n
f o r
the hydration of ole?n.
A
number
o f
c a t a l y s t s
have
been
k n o w n a s
e f f e c t i v e
f o r d i r e c t h y d r a t i o n o f o l e ? n s . P a r t i
c u l a r l y , t h e u t i l i t y
o f h e t e r o p o l y -a c i d and w a t e r - s o l u b l e s
a l t s t h e r e o f f o r
t h e h y d r a t i o n
o f
o l e ? n t o p r o d u c e a l c o h o l andether s
known from B r i t i s h
P a t .
No. 4 8 7 , 3 8 4 . More s p e c i ?
c a l l y , t h e h e t e r o p o l y - a c i d i n c l u d e s
b o r o t u n g s t i c a c i d ,
p h o s p h o t u n g s t i c
a c i d , s i l i c o t u n g s t i c a c i d ,
s i l i c o m o l y b
d i c
a c i d ,
and
phosphomolybdic a c i d . I t i s known t h a t
t h o s e h e t e r o p o l y - a c i ds
g e n e r a l l y e x h i b i t
o l e f i n - h y d r a t
i n g
a c t i v i t y a l s o
i n t h e form
o f
w a t e r - s o l u b l e
s a l t s
t h e r e o f . To w i t , h e t e r o p o l y - a c i d
i n
w a t e r i s s u b s t a n
t i a l l y
d i s s o c i a t e d
i n t o a hydrogen i o n and a
h e t e r o p o l y
a c i d i o n , s i m i l a r l y t o o r d i n a r y m i n e r
a l a c i d , a n d shows
t h e
c a t a l y t i c
a c t i v i t y
f o r
h y d r a t i o n o f
o l e f i n s a s t h e
r e s u l t
o f t h e concurrent presence of t h e tw o t y p e s o f
ions.
.
T h u s , i n t h e
h y d r a t i o n r e a c t i o n
o f o l e ? n , t h e
h e t e r o p o l y - a c i d i o n
a c t s a s
t h e main
c a t a l y s t ,
w h i l e
t h e
hydrogen i o n
e f f e c t i v e l y
a c t s a s an a c t i v a t o r o f t h e
f o r m e r . For h i s r e a s o n , w h en a h e t e r o p o l
y - a c i d i s
u s e d
a s
t h e
c a t a l y s t
f o r
h y d r a t i o n o f
o l e ? n
i n
t h e
form
o f
a l t ,
a n e u t r a l
s a l t e x h i b i t s o n l y v e r y
m i n o r
c a t a l y t i c
a c t i v i t y ,
and t h e r e f o r e an a c i d i c s a l t i s advantageously
em
p l o y e d .
I n o t h e r w o r d s , t h e c o n c u r r e n t p r e s e n
c e
o f
h e t e r o p o l y - a c i d i o n s a n d h y d r o g e n i o
n s
i n t h e
a q u e o u s
s o l u t i o n
p r o v i d e s t h e a d v a n t a g e o u s
c a t a l y s t
s y s t e m . As
t h e t y p i c a l m e t a l s
f o r f o r m i n g
w a t e r - s o l u b l e , a c i d i c
s a l t s of t h e
h e t e r o p o l y - a c i d s ,
a l k a l i
metals
s uch a s s o
dium
and
p o t a s s i u m ;
and c a l c i u m ,
magnesium,
c a d
mium a n d
aluminum may
be
n a m e d .
A c c o r d i n g
t o
t h e i n v e n t i o n , t h e
optimum r e s u l t s a r e
5
2
a c i d i o n s . Thus w e con?rmed
t h e
n e c e s s i t y
t o
a v o i d
t h e
s u b s t a n t i a l p r e s e n c e o f f r e e i r o n i o n
s .
A c c o r d i n g
t o
t h e i n v e n t i o n , t h e c a t a l y s t s y s t e m
i s
composed o f
h e t e r o p o l y - a c i d i o n s a n d h y d r o g e n i o
n s a s
a l r e a d y m e n t i o n e d .
F o r
t h i s r e a s o n t h e h e t e r o p o l y - a c i d
i o n - c o n t a i n i n g
a q u e o u s
s o l u t i o n
i s c o n t a c t e d w i t h
o l e
? n
a t
a
pH
a n g i n g
f r om
2 . 0 t o
4 . 5 .
Suc h
an
a c i d i c
s o l u t i o n a l w a y s
d i s s o l v e s i r o n
o r i r o n
c o m p o u nd s
a s i t
c o n t a c t s
w i t h
t h e r e a c t o r , d i s t i l l a t i o n s y s t e m o f t
h e
f o r m e d a l c o h o l , t r a n s f e r r i n g
p i p e s ,
e t c . ,
a n d c o n s e ~
q u e n t l y
u n a v o i d a b l y c o n t a i n s f r e e i r o n i o n
s
a t
g r a d u a l l y
i n c r e a s i n g c o n c e n t r a t i o n . F u r t h e r m
o r e ,
s i n c e
t h e s u b
j e c t
p r o c e s s
concerns
h y d r a t i o n ,
w a t e r
must
be
added
, . t o t h e r e a c t i o n system
and,
because the water i t s e l f
20
25
30
35
4 0
4 5
o b t a i n e d
from'the h y d r a t i o n o f
o l e ? n u s i n g
t h e
;
h e t e r o p o l y - a c i d , when
t h e molar
c o n c e n t r a t i o n
o f c a t a
l y t i c
component r a n g e i s
l / 4 0 , 0 0 0
H300,
and t h e pH
r a n ge i s
2.0 -
. 5 .
The
reaction
i s
p e r f o r m e d
at
1 0 0 ~
500 k g l c m z , and a t 150 370 C . The h i g h e r t h e
molec
u l a r w e i g h t o f
t h e
o l e ? n , t h e
l o w e r
may b e
t h e r e a c t i o n
t e m p e r a t u r e ,
w i t h i n t h e
a b o v e - s p e c i ? e d r a n g e .
F o r
example, t h e temperature
range
o f 200 - 350 C . i s
recommended f o r h y d r a t i o n o f e t h l e n e ,
w h i l e
i t i s 200
-
3 0 0 C .
f o r
p r o p y l e n e ,
and 170 - 2 5 0 ? C . f o r b u t e n e .
The a t a l y t i c
a c t i v i t y o f
t h o s e h e t e r o p o l y - ac i d i o n s
i n
t h e h y d r a t i n g r e a c t i o n
o f o l e ? n s
t h u s
b e i n g e x t r e m e l y
h i g h ,
w e
f o u n d t h a t t h e d u r a b i l i t y
o f
t h e
a c t i v i t y i s
r e l a t i v e l y
s h o r t . For e x a m p l e , o u r e x p e r i m e n t s
con
?rmed t h a t i n
a n
i r o n
r e a c t o r , 10%
o f
t h e
c a t a l y s t
de
c o m p o s e d ,
u n d e r t h e , r e a c t i o n c o n d i t i o n s o f 3 0 0
C .
a n d
1 5 0
k g / c m ,
w i t h i n
a p p r o x i m a t e l y
6
d a y s .
5 0
55
60
We
earched
f o r t h e
cause
o f
such
d e c r e a s e o f
a c t i v
i t y
o c c u r r i n g w i t h
d e c o m p o s i t i o n
o f
t h e
c a t a l y s t ,
e t c . ,
a n d d i s c o v e r e d t h a t t h e d e c r e a s e i n c a
t a l y t i c
a c t i v i t y
c o n t a i n s ' i r o n i o n s a l t h o u g h i n
m i n o r q u a n t i t i e s , f r o m
t h i s s o u r c e a l s o i r o n i o n s g r a d u a l l
y
accumulate
i n t h e
r e a c t i o n s y s t e m .
I t
i s
now found,
according
t o
t h e
i n v e n t i o n ,
t h a t by
s u b s t a n t i a l l y
a v o i d i n g t h e c o n c u r r e n t p r e s e n c e
o f f r e e
i r o n w i t h
t h e
c a t a l y s t
i o n s composed c h i e ? y o f
h e t e r o p o l y - a c i d
i o n s ,
t h e
c a t a l y s t
s y s t e m
c a n
b e u s e d
r e p e t i t i v e l y , w i t h o u t
s u b s t a n t i a l
r e d u c t i o n i n t h e c a t a
l y t i c a c t i v i t y o v e r p r o l o n g e d p e r i o d
s
o f t i m e .
I t
h a s
p r e v i o u s l y b e e n
r e p o r t e d
t h a t i r o n
s i l i c o t u n g
s t a t e ,
i r o n
s i l i c o p h o s p h a t e ' ,
f e r r i c s u l f a t e ,
f e r r i c
m o l y b
d a t e ,
e t c .
a r e
used
a s c a t a l y s t s f o r t h e
hydration r e a c
t i o n
o f
o l e ? n s
( f o r e x a m p l e ,
B r e n n s t o f f - C h e m .
3 8 , 3 2 1
( 1 9 5 7 ) ,
U . S . P a t e n t 2 . 8 7 6 , 2 66 ) . I n view
o f t h i s kn o w n
i n f o r m a t i o n , i t
i s
q u i t e
unexpected t h a t
even a v e r y
s m a l l
amount
f i r o n i o n s
a b r u p t l y r e d u c e s
t h e c a t a l y t i c
a c t i v i t y
o f h e t e r o p o l y - a c i d
i o n s a s
d e s c r i b e d a b o v e .
T h u s , a c c o r d i n g t o
t h e
s u b j e c t p r o c e s s f o r
t h e
p r e p a
r a t i o n o f
m o n o h y d r i c
a l c o h o l w h i c h c o m p r i s e s c o n t a c t
i n g
a
m on o o le ?n o f
2
t o 4 carbon atoms
w i t h
an aque
o u s
s o l u t i o n
c o n t a i n i n g h e t e r o p o l y - a ci d
a n d
t h e r e b y
h y d r a t i n g t h e o l e ? n , t h e
c h a r a c t e r i s t i c
f e a t u r e s r e s i d i n g
i n
t h a t t h e aqueous
s o l u t i o n
c o n t a i n s t h e
h e t e r o p o l y
a c i d i o n a t
a
concentration of
t
l e a s t 1/40,000 m o l
per
l i t e r and
h a s
a
p H
r a n g i n g from 2 . 0 t o 4 . 5 . Moreover,
w hen t h e s o l u t i o n i s
h e a t e d
t o t h e
t e m p e r a t u r e
s u f ?
c i e n t l y h i g h f o r
i n i t i a t i n g t h e h y d r a t i o n
r e a c t i o n , w h i l e
t h e f r e e
i r o n
i o n c o n c e n t r a t i o n
i n t h e
s o l u t i o n
i s
main
t a i n e d a t n o t
h i g h e r
t h a n
1 0
ppm
u b s t a n t i a l l y
t h r o u g h
o u t t h e w h o l e p e r i o d o f
s a i d r e a c t i o n ,
monohydric
a l c o h o l
c o r r e s p o n d i n g t o
t h e
s t a r t i n g ole?n
can be
p r e p a r e d w i t h h i g h
c o n v e r s i o n a n d
h i g h
s e l e c t i v i t y ,
w i t h o u t any
u b s t a n t i a l
r e d u c t i o n i n t h e
c a t a l y s t s a c t i v
i t y f o r a
p r o l o n g e d
p e r i o d .
The
p r e c i s e
mechanism w i t h
which t h e f r e e i r o n i o n
c a u s e s
t h e
d e c r e a s e
i n c a t a l y t i c
a c t i v i t y
i s
n o t
y e t
c l e a r .
Our
o p i n i o n i s t h a t e i t h e r
t h e
c a t a l y s t i o n
a n d
i r o n
i o n
r e a c t
t o f or m
p r a c t i c a l l y
i n e r t , i n s o l u b l e
m a t t e r , o r t h e
i r o n i o n
a c t s c a t a l y t i c a l l y t o
promote d e c o m p o s i t i o n
o f
t h e
h e t e r o p o l y - a c i d .
C o n c e r n i n g t h e d e c r e a s e
i n
t h e
c a t a l y t i c
a c t i v i t y
w h i c h h a s
b e e n r e g a r d e d a s b e i n g
caused by t h e c a t a l y s t s
d e c o m p o s i t i o n , i t
i s
con?rmed
t h a t
s u c h
d e c r e a s e i s n o t
v e r y a p p r e c i a b l e
a f t e r
t h e f i r s t
c i r c u l a t i o n
o f t h e
c a t a l y s t
s o l u t i o n
i n
t h e f l o w r e a c t i o n
s y s t e m ,
but upon r e p e t i t i v e r e c i r c u l a t i o n o f t h e
s o l u
t i o n ,
i r o n
i o n s
g r a d u a l l y a c c u m u l a t e i n
t h e
s o l u t i o n t o
c a u s e
a
marked r e d u c t i o n i n t h e
c a t a l y t i c
a c t i v i t y .
This
can be
c l e a r l y
demonstrated by our
e x p e r i
m e n t s . For e x a m p l e , t h e c o r r e l a t i o n o
f
t h e
c a t a l y s t s
decomposition r a t i o n (which
s
t h e
r e d u c t i o n
r a t i o and
t a k e s
p l a c e w hen i r o n i o n s
a r e
s u b s t a n t i a l l y .
p r e s e n t
i n
t h e r e a c t i o n
s y s t e m
f o r p r a c t i c i n g t h e
p r e s e n t ' i n y e n
t i o n , i . e . , t h e
a q u e o u s
s o l u t i o n c o n t a i n i n g h e t e r o p o l y
h a s s u b s t a n t i a l l y
e q u i v a le n t s i g n i ? c a n ce
t o t h e l o w e r i n g
r a t i o i n t h e
c a t a l y t i c
a c t i v i t y ) w i t h t h e c o n c e n t r a t i o n o
f
" c o n c u r r e n t l y e x i s t i n g i r o n
i o n s
i s i l l u s t r a t e d
i n
F I G . 1 ,
, a s to a n a q u e o u s
solution o f s i l i c o t u n g s t i c
acid
a t
1 . 0 3
-
8/11/2019 US3996298.pdf
4/9
3 , 9 9 6 , 2 9 8
3
m o l / l i t e r c o n c e n t r a t i o n , u s e d
a t
2 9 0 C . and
150
kglcmzG o f
p r o p y l e n e f o r
240 h o u r s .
As can be under
s t o o d fr o m FIG. 1 , u p t o 5 ppm f i r o n i o n
concentra
t i o n h a r d l y i n t e r f e r e s w i t h
t h e
c a t a l y s t s
a c t i v i t y ,
i . e . ,
t h e c a t a l y s t s decomposition r a t i o
i s
no
m ore
t h a n 2%
whereas t h e
d e t r i m e n t a l
e f f e c t
of t h e i r o n
i o n concen
t r a t i o n becomes i n c r e a s i n g l y n o t a b l e a s
i t i n c r e a s e s
f r o m
10
t o 1 5
p p m .
At
1 5
p p m ,
n e a r l y 10%
of
the
c a t a l y s t
i s dec o m p o s ed a n d , beyond 1 5 p p m , t h e c a t
a
l y t i c
a c t i v i t y
i s
decreased
a t s u c h
a
r a t e a s not t o be
i n d u s t r i a l l y a c c e p t a b l e .
S u b s t a n t i a l l y
t h e same t e n
d e n c y i s r e c o g n i z e d i n t h e c a t a l y t i c a
c t i v i t i e s o f o t h e r
h e t e r o p o l y - a c i d
i o n s ,
e . g . ,
b o r o t u n g s t i c a c i d
i o n s ,
p h o s
p h o t u n g s t i c
a c i d i o n s , s i l i c o m p o l y b d i c a c i d i o n s
, a n d
p h o s p h o m o l y b d i c a c i d i o n s .
A l s o
t h e d e c o m p o s i t i o n
r a t e
i s s u b s t a n t i a l l y u n a f f e c t e d
by
pH a r i a t i o n s i n
t h e
s o l u t i o n w i t h i n t h e
a c i d i c
r a n g e . According
t o
t h e
p r e
s e n t
i n v e n t i o n , t h e r e f o r e , t h e c o n c e n t r a
t i o n
o f
f r e e i r o n
i o n s
i n t h e c a t a l y t i c aqueous
s o l u t i o n t o
be s u p p l i e d t o ,
o r caused t o be p r e s e n t i n , t h e h y d r a t i o
n
r e a c t i o n
s y s
tem, through r e c i r c u l a t i o n
or o t h e r
k n o w n
means, i s
c o n t r o l l e d
t o be n o t h i g h e r t h a n
1 0 ppm nd p r e f e r a b l y
below
5
p p m .
As sources
o f
f r e e
i r o n i o n s
w hic h accumulate i n t h e
r e a c t i o n
s y s t e m
d u r i n g t h e p r e p a r a t i o n o f a l c o h o l
t h r o u g h
t h e
d i r e c t h y d r a t i o n o f o l e ? n ,
t h e
f o l l o w i n g
can be enumerated:
a . E l u t i o n fr o m
c o n s t r u c t i o n
m a t e r i a l s o f
t h e e q u i p ;
ment employed,
such
a s
t h e
r e a c t o r , d i s t i l l a t i o n c o l
umn,
c o n n e c t i n g
p i p e s ; e t c . , a n d
b . I n t r o d u c t i o n from t h e
w a t e r ' s u p p l y
t o t h e h y d r a
t i o n r e a c t i o n s y s t e m , t h e former b e i n g t h
e more
s i g n i ?
cant.
A c c o r d i n g l y ,
i n
t h i s i n v e n t i o n t h e f r e e i r o n i o n con
c e n t r a t i o n
i n
t h e r e a c t i o n
system
i s
c o n t r o l l e d
so
a s
n e v e r t o
exceed
1 0 ppm, p r e f e r a b l y
5
ppm, by p r e v e n t
i n g
t h e e n t r a n c e and a c c u m u l a t i o n o f
f r e e i r o n
i o n
i n
t h e r e a c t i o n
s y s t e m
t h r o u g h t h e r o u t e s
( a )
and ( b )
a s
m u c h
a s p o s s i b l e , and f n e c e s s a r y
( a s
i n t h e m a j o r i t y o f
c a s e s ) , b y r e m o v i n g t h e
i r o n
i o n s u n a v o i d a b l y b r o u g h t
i n t o t h e s y s t e m a n d / o r
i n a c t i v a t i n g
t h e
s ame
w i t h , f o r
e x a m p l e ,
a
c h e l a t i n g
a g e n t .
As
t h e
means
t o
a d v a n t a g e o u s l y p r a c t i c e t h e s u b j e c
t
i n v e n t i o n , f o r e x a m p l e , t h e f o l l o w i n
g s e v e r a l embodi
ments can
be emplo yed,
i . c o n t r o l l i n g t h e
f r e e
i r o n i o n c o n c e n t r a t i o n i n t h e
aqueous s o l u t i o n t o keep i t below
1 0 ppm, p r e f e r a b l y
below 5
ppm,
by p r a c t i c i n g t h e h y d r a t i o n r e a c t i o n i
n a
reactor
o f
w h i ch
a t
l e a s t
the
i n t e r n a l surfaces
are
con
s t r u c t e d
o f n o n - f e r r o u s m e t a l which s n o n - c o r r o s
i v e
t o
t h e aqueous s o l u t i o n .
As
t h e
n o n - f e r r o u s m e t a l s
u s e f u l f o r t h e above
pur
p o s e , f o r e x a m p l e , n i c k e l , c h r o m i u m ,
t i t a n i u m , z i r c o
n i u m ,
t a n t a l u m , s i l v e r , g o l d , a n d p l a t i n u m
may b e
named.
I t
s h o u l d be
a p p a r e n t t h a t ,
w h i l e t h o s e n o n - f e r
r o u s metals may
e used a s
t h e c o n s t r u c t i o n m a t e r i a l
of
t h e r e a c t o r ,
l i n i n g o r
p l a t i n g o f
t h e
i n t e r n a l s u r f a c e s
o f
t h e r e a c t o r w i t h t h o s e m e t a l s i s a l s o e
f f e c t i v e .
T h u s ,
conventional
f e r r o u s
r e a c t o r s
can be
improved t o
be
s u i t e d f o r
u s e
i n t h e s u b j e c t pr o c e s s , b y
l i n i n g o r
p l a t i n g
them w i t h t h o s e n o n - f e r r o u s m e t a l s .
A l s o
i r o n - c o n t a i n
i n g
a l l o y s w h i c h
h a r d l y a l l o w
e l u t i o n
o f
i r o n
i o n s
c a n
b e
u s e d
under
c e r t a i n
c i r c u m s t a n c e s .
O b v i o u s l y ,
i t
i s
m ore d e s i r a b l e t o c o n s t r u c t n o t
o n l y
t h e
r e a c t o r , b u t
a l s o t h e d i s t i l l a t i o n column
o r s e p a r a t
i n g
t h e f o r m e d
a l c o h o l
a n d
c o n n e c t i n g p i p e s ,
f r o m
t h o s e n o n - f e r r o u s m e t a l s . However,
s u c h
w i l l
m a k e h e
r e a c t i o n a p p a r a t u s
e x t r e m e l y
e x p e n s i v e . F o r
t h i s
r e a
25
30
35
4 5
5 0
55
60
65
4
s o n , i n p r a c t i c e
i t
i s v i r t u a l l y
i m p o s s i b l e
t o
c o m p l e t e l y
p r e v e n t
t h e
e n t r a n c e
o f
f r e e i r o n i o n s i n t o t h e r e a c t i o n
s y s t e m
a n d , t h e r e f o r e , i t i s n o r m a l l y d e s i r a
b l e , ( p r o b a
b l y e x c e p t i n g t h e
c a s e w h e r e i n v e r y
c a r e f u l l y r e ? n e d ,
i r o n - f r e e w a t e r i s u s e d ) ,
t o c o n c u r r e n t l y p r a c t i c e
t h e
removal o f
f r e e i r o n i o n s from t h e aqueous s o l u t i o n
c o n t a i n i n g h e t e r o p o l y - ac i d i o n s b y t h
e means l a t e r
d e s c r i b e d ,
o r
by
i n a c t i v a t i o n
o f
t h e i o n
by
c h e l a t i o n ,
etc.
i i . C o n t r o l l i n g
o f t h e f r e e
i r o n
i o n c o n c e n t r a t i o n i n
t h e
aqueous s o l u t i o n t o be below
1 0
ppm, p r e f e r a b l y
b e l o w 5
ppm,
s u b s t a n t i a l l y t h r o u g h o u t t h e w h o l e p
e
r i o d o f
t h e
s p e c i ? e d h y d r a t i o n p r o c e s s , b y c o n t a
c t i n g
t h e h e t e r o p o l y -a c i d
i o n - c o n t a i n i n g a q u e o u s s o l u t i o n ,
w h i c h
i s
o b t a i n e d
b y
s e p a r a t i n g t h e f o r m e d monohy
d r i c
a l c o h o l f rom h e r e a c t i o n m i x t u r e a f t e
r
c o m p l e t i o n
o f t h e
h y d r a t i o n ,
w i t h a c a t i o n e x c h a n g e r , t h e r e b y a d
s o r b i n g or
removing-by
r e a c t i o n t h e
f r e e
i r o n i o n s con
t a i n e d i n
s a i d s o l u t i o n ,
and
r e c y c l i n g
t h e
aqueous s o l u
t i o n
t o
t h e
h y d r a t i o n r e a c t i o n s y s t e m .
Exchangers s u i t e d
f o r t h e
removal o f
f r e e
i r o n i o n s i n
t h e
aqueous
s o l u t i o n ,
a r e c a t i o n
exchange
r e s i n s
and
i n o r g a n i c
c a t i o n
e x c h a n g e r s . More
p e c i ? c a l l y , c a t i o n
e x c h a n g e r e s i n s s u c h
a s
A m b e r l i t e
( t r a d e m a r k ,
p r o d u c t
o f Rohm &
Haas
C o . ,
U . S . A . ) , D i a i o n
( t r a d e m a r k ,
p r o d u c t o f M C I ,
J a p a n )
a n d c h e l a t i n g
c a t i o n
e x c h a n g
e r s
which
f orm
c h e l a t e com p ounds w i t h i r o n i o n s ;
and
i n o r g a n i c c a t i o n
e x c h a n g e r s
c o m p o s e d
o f
p h o s p h a t e s
o f t h e m e t a l s o f Group
IV
a
o f
t h e p e r i o d i c t a b l e ; f o r
example, are u s e f u l f o r this p u r p o s e . ,
The
t r e a t m e n t o f t h e aqueous s o l u t i o n w i t h
s u c h
c a t i o n e x c h a n g e r s
c a n b e e f f e c t e d b y
c o n v e n t i o n a l l y
p r a c t i c e d
i o n - e x c h a n g i n g
m e a n s , s u c h
a s
p a s s i n g t h e
a b o v e - s p e c i ? e d
h e t e r o p o l y - a c i d
i o n - c o n t a i n i n g
a q u e
ou s s o l u t i o n through a tower packed w i t h t h e i o n
ex
changer.
A y p i c a l
embodiment o f
t h i s
method i s s h o w n
a s
a
f l o w c h a r t
i n
F I G . 2 .
R e f e r r i n g t o s a i d
? g u r e , t h e s t a r t
i n g o l e f i n i s i n t r o d u c e d i n t o t h e r e a c
t o r ( 3 ) t h r o u g h
p i p e ( 1 ) , and t h e c a t a l y t i c s o l u t i o n i s
s u p p l i e d i n t o t h e
same r e a c t o r t h r o u g h p i p e
( 4 ) . The
w a t e r r e p l e n i s h
ment t o make
u p
t h e
water reduction due
t o i t s con
s u m p t i o n
d u r i n g
t h e
h y d r a t i o n a n d
f r o m
o t h e r m i n o r
c a u s e s , i s
e f f e c t e d
from
p i p e
( 2 ) .
The
r e a c t e d
s o l u t i o n ,
i . e . , a mixed
aqueous s o l u t i o n
o f t h e
r e a c t i o n p r o d u c t
a n d c a t a l y s t ,
i s
t r a n s f e r r e d t h r o u g h p i p e ( 5 ) ,
a n d
e x
c h a n g e s
h e a t w i t h t h e
r e c i r c u l a t i n g
c a t a l y t i c
s o l u t i o n
a t
t h e
h e a t
exchanger ( 1 2 ) . Then t h e s o l u t i o n
i s
s e n t t o
t h e
d i s t i l l a t i o n
column
( 6 ) ,
t o
b e
s e p a r a t e d
i n t o t h e
d e s i r e d
p r o d u c t , i . e . , a l c o h o l ,
a n d t h e
c a t a l y t i c s o l u
t i o n . The a l c o h o l i s
f u r t h e r s e n t i n t o
t h e
r e f i n i n g
c o l
u m n
( 8 )
t h r o u g h p i p e ( 7 ) . The r e ? n e d a l c o h o l i s
w i t h
d r a w n f r o m
p i p e
( 9 ) . The c a t a l y t i c s o l u t i o n s e p a r a t e
d
a t t h e d i s t i l l a t i o n column ( 6 )
i s
s e n t t o t h e i r o n - r e m o v
i n g c o l u m n ( 1 1 ) p a c k e d w i t h t h e i o n e x c
h a n g e r ,
t h r o u g h p i pe
( 1 0 ) ,
t o b e
removed o f t h e
f r e e i r o n i o n ,
and t h e n r e c y c l e d t o t h e r e a c t o r ( 3 ) t h r
o u g h p i p e
( 4 ) .
i i i .
C o n t r o l l i n g o f
t h e f r e e i r o n
i o n c o n c e n t r a t i o n
i n
t h e aqueous s o l u t i o n
t o
be n o t h i g h e r t h a n 1 0
ppm,
p r e f e r a b l y b e l o w 5
p p m ,
s u b s t a n t i a l l y t h r o u g h o u t t h e
h y d r a t i o n
r e a c t i o n , b y
a d d i n g t o t h e a q u e o u s s o l u t i o n a
s t a b i l i z e r which can form a c h e l a t e c o m p o u
nd w i t h t h e
free
iron
ion
i n
s i t u .
U s e f u l s t a b i l i z e r s
a r e , f o r e x a m p l e , o r t h o - p h o s p h o r i
c
a c i d ,
m e t a - p h o s p h o r i c a c i d , p y r o p h o s p h o r
i c a c i d , a n d
p o l y p h o s p h o r i c a c i d w h i c h
c a n
b e e x p r e s s e d b y , t h e
g e n e r a l f o r m u l a , P 2 O 5 ' n I - I 2 O
( n
s t a n d s
f o r a n
i n t e g e r ) ;
a l k a l i
m e t a l
s a l t s t h e r e o f ; e t h y l e n e d i a m i n e t e t r
a a c e t i c
-
8/11/2019 US3996298.pdf
5/9
3 , 9 9 6 , 2 9 8
5
a c i d , n i t r i l o t r i a c e t i c
a c i d ; a n d t h e i r
w a t e r - s o l u b l e
s a l t s ;
e t c .
The s t a b i l i z e r s
t o be
used i n accordance with t h i s
embodiment
a r e c h e l a t i n g
a g e n t s
which
e x h i b i t h i g h
r e a c t i v i t y
w i t h
f r e e
i r o n
i o n s ,
b u t s h o w
no
d e t r i m e n t a l
e f f e c t o n t h e o l e ? n h y d r a t i n g
a c t i v i t y
o f t h e
c a t a l y s t
s y s t e m c o m p o s e d c h i e ? y o f h e t e r o p o l y
- a c i d . P a r t i c u
l a r l y p r e f e r r e d s t a b i l i z e r s a r e p o l y
p h o s p h o r i c a c i d i n
which t h e P205
content
i s no l e s s
than 72.4
w t . %, and
w a t e r - s o l u b l e s a l t s
t h e r e o f
w i t h , f o r e x a m p l e ,
sodium
6
p u r g e d f r o m t h e a u t o c l av e , a n d t h e r e m a
i n i n g c a t a l y t i c
s o l u t i o n c o n t a i n i n g t h e formed a l c o h o l
wa s e t s t a n d f o r
100 h o u r s a t 3 0 0
C .
and 100
kg/cm2
G, i n t h e s a m e
c o n t a i n e r i n
t h e
a u t o c l a v e . T h e r e a f t e r
t h e
r e d u c t i o n i n
s i l i c o - t u n g s t i c a c i d i o n c o n c e n t r a t
i o n
i n
t h e s o l u t i o n
w a s measured,
w i t h
t h e r e s u l t s a s s h o w n i n t h e l a s t
column
o f
Table
1 . The i r o n i o n c o n c e n t r a t i o n
i n
t h e
s o l u t i o n a f t e r t h e r e a c t i o n w a s
14
ppm h e n t h e s t a i n
l e s s s t e e l
reactor
w a s
u s e d ,
and
i n a l l
other
c a s e s
no
and
p o t a s s i u m .
Normally t h e
u s e o f t h o s e s t a b i l i z e r s
a t 1 0 m ore than 1 p p m .
Table 1
C a t a l y t i c
S o l u t i o n
R e s u l t
SW C on- Alcohol SW
Co n - c e n t r a -
Reaction
conditions
concen-
S e l e c -
Reduction
s t r u c t i o n t i o n Temp.
P r e s .
Time
Main
t r a t i o n t i v i t y R a t i o
Run N o . M e t a l ( g / l ) p H
( C . ) ( k g / c m G )
( h r . ) Ole?n P r o d u c t ( w t . %) ( % ) ( % / 1 0 0 h r s
. )
1
S t a i n l e s s 3 . 0 3 . 0
230
200
1
Propylene 1 5 0 -
8 . 6
99
4 . 8
( C o n t r o l ) s t e e l p r o p a n o l
S U S 2 7
2
Ni 3.0 3.0 230 200 l 8.7
99
1 . 2
3 Ni 1 . 0 2.8
230
200
l 10.7
98 0.3
4
Cr
3.0 3.0
2 30
200
1
9
8 . 8
99
0.8
5
Ag
3.0 3.0
2 30 2 0 0 l '
8.6
99
1 . 0
6 Ti
3.0 3.0 . 230 200
1 8.7
99
0.8
7 Zr 3.0 3.0 2 30 2 0 0 l
8.8
99 1 . 2
8
Ta 3.0 3.0
23 0
200
1 8.8
9 9
0.8
9
Au 3.0 3.0
2 30 2 0 0
l
8.9 99
0.3
10 Pt
3.0 3.0
230 200
1
9.0
99
0.2
1 1
Cr
0.5
3.3
250 200 1 10.2
99
0.2
12 T i 1 . 0 3
3 250 200
l Ethylene Ethanol
6 . 8
99
0 . 7
1 3 T i
10
3 . 3 250 200
1
Mixed
Mixed 9 . 6
99
0 . 8
b u t y l e n e b u t a n o l
the
r a t i o
o f
a roximatel
0.01
r a m
e r
l i t e r o f the
p p y
g
p
EXAMPLE
s o l u t i o n i s s u f ? c i e n t t o achieve t h e d e s i
r e d
e f f e c t .
No
c o r r e s p o n d i n g l y
i m p r o v e d
r e s u l t c a n b e e x p e c t e d from
t h e
a d d i t i o n
o f m o r e than
1
gr a m o f s uch a s t a b i l i z e r
per
l i t e r
o f t h e
s o l u t i o n .
Only a few e x e m p l a r y
embodiments
h a v i n g been
e x p l a i n e d
i n t h e
f o r e g o i n g i t e m s ( i ) t h r o u g h
( i i i )
a s t h e
speci?c m e a n s f o r reducing
f r e e
i r o n i o n s
i n
t h e
c a t a
l y t i c s o l u t i o n ,
and i t s h o u l d
be a p p a r e n t t h a t
t h e scope
of
h i s
i n v e n t i o n
i s
by
no
me an s
l i m i t e d
t h e r e t o .
Other
me an s which
a r e
e a s i l y
c o n c e i v a b l e by t h o s e
s k i l l e d i n
t h e a r t may, o f c o u r s e be empl oyed. I t
i s
a l s o p r e f e r a b l e
t o practice
t w o
or more o f
those
m e a n s concurrently,
t o
maintain
t h e f r e e i r o n i o n concentration i n t h e cata
l y t i c s o l u t i o n
a t
a s t i l l lowered l e v e l .
EXAMPLE
A ontainer which w a s constructed of h e metal spec
i ? e d i n Table
1 , second column, w a s
c h a r g e d w i t h
150
m l o f t h e c a t a l y t i c
s o l u t i o n
c o n t a i n i n g
s i l i c o t u n g s t i c
a c i d i o n ( S W ) a t t h e
c o n c e n t r a t i o n
a l s o s p e c i ? e d i n
Table 1 ,
and was
i n s e r t e d i n t o
a SOO-ml c a p a c i t y s t a i n
l e s s
s t e e l
a u t o c l a v e .
The
speci?ed
ole?n w a s
i n t r o
duced
i n t o
t h e c o n t a i n e r under h e a t i n g , u n t i l t h e
tem
-35
4 0
4 5
5 0
C a t a l y t i c s o l u t i o n s
e a c h
c o n t a i n i n g
s i l i c o t u n g s t i c
a c i d ( S W A ) , b o r o t u n g s t i c a c i d (BWA),
p h o s p h o t u n g
s t i c
a c i d
(PWA),
S i l i c o m o l y b d i c
a c i d
(SMA),
o r
p h o s
p h o m a l y b d i c a c i d (PMA)
a t
c o n c e n t r a t i o n
o f 3 g / l i t e r
were
prepared,
and
t h e i r
pH a s adjusted t o 2 . 8
. 0
with N a O l - l . I n
each
run
t h e
c a t a l y t i c s o l u t i o n
w a s
i n
troduced i n t o
a s i l v e r - l i n e d
high p r e s s u r e r e a c t o r f r o m
t h e
upper p a r t t h e r e o f ,
a t a r a t e o f
3 k g / h r .
p e r 1
l i t e r
o f
t h e r e a c t o r s
c a p a c i t y .
S i m u l t a n e o u s l y
p r o p y l e n e
w a s introduced i n t o the
s a m e r e a c t o r f r o m
the bottom,
a t
a
r a t e
o f 0 . 2 6
k g / h r . , t o be c o n t i n u o u s l y
hydrated
under t h e r e a c t i o n c o n d i t i o n s o f 260 C .
and
150
k g / c m 2 G . The r e a c t i o n
p r o d u c t
w as withdrawn from
t h e bottom
o f
t h e r e a c t o r t o g e t h e r w i t h t h e c a t a l y t
i c
s o l u t i o n ,
w h i c h
w a s s u b s e q u e n t l y s e p a r a t e d b y d i s t i l
l a
t i o n .
The
s e p a r a t e d c a t a l y t i c s o l u t i o n w as r e c i
r c u l a t e d
i n t o t h e r e a c t o r .
The r e a c t o r
w a s
continuously oper
a t e d f o r 500 h o u r s ,
but
t h e
i r o n
i o n c o n c e n t r a t i o n
i n
t h e r e c i r c u l a t e d
a q ue o u s
s o l u t i o n
a t
no time
exceeded
1
ppm.
The a v e r a g e
o n e - p a s s
c o n v e r s i o n , i s o p r o p a n o l
c o n c e n t r a t i o n ,
s p a c e t i m e
y i e l d ( S . T . Y . ) a n d i s o p r o p a
n o l s e l e c t i v i t y o f t h e i n i t i a l
2 4 h o u r s , a n d
o f t h e
l a s t 2 4
p e r a t u r e and p r e s s u r e i n
t h e
c o n t a i n e r reached t h e 5 5 h o u r s ,
a r e
s h o w n i n Table
2
b e l o w .
Table
2
I n i t i a l
24 Hours
L a s t
24 Hours
SWA
BWA PWA SMA
PMA SWA
BWA
PWA
SMA PMA
Conversion
( 7 c )
67
64 66 68
67
67 64 65
67 56
Concentration (wt.%)
6 . 2 5 . 9 6 . 1
6 . 3 5 . 3
6 . 2 5 . 9 6 . 0 6 . 2
5 . 3
S . T . Y . ( k g / k g . c a t . h r . )
2 1 . 2
2 0 . 3
2 0 . 9
2 1 . 5 1 8 . 0 2 1 . 2
2 0 . 3
2 0 . 7
2 1 . 4
2 1 . 3
S e l e c t i v i t y ( 9 2 )
98
99
98
98 99 98 99
98 98 99
p r e d e t e r m i n e d v a l u e s ,
and h y d r a t e d f o r
a n h o u r . The
r e s u l t s
were a s
s h o w n
i n the
s a m e t a b l e .
I n
o r d e r t o determine
t h e decomposition r a t e o f t h e
c a t a l y s t , a f t e r
t h e r e a c t i o n t h e u n r e a c t e d
ole?n w a s
65
The above r e s u l t s demonstrate t h a t t h e a v e r a g
e
p e r
f o r m a n c e
o f
t h e
l a s t
24 h o u r s
o p e r a t i o n
i s s u b s t a n t i a l l y
t h e
s a m e
a s t h a t
of
t h e
i n i t i a l 24 h o u r s ,
a s t o
a l l of
t h e
measurements.
-
8/11/2019 US3996298.pdf
6/9
3 , 9 9 6 , 2 9 8
7
S i m i l a r
e x p e r i m e n t s
were
performed w i t h t i t a n i u m
and z i r c o n i u m r e a c t o r s , and t h e r e s u l t s
o f 500 h o u r s
8
i n F I G . 2
w as
n o t
u s e d ) , a r e a l s o g i v e n a s Runs 6
t h r o u g h 1 0 .
Table
3
Fe
Concen
Concentration t r a t i o n i n
o f
C a t a l y t i c C a t a l y t i c Alcohol
R u n C o m p o n e nt S o l u t i o n Y i e l d
N o .
C a t a l y s t
( m o l / l i t e r )
( p p m )
( k g / h r )
Exam ple s i l i c o t u n g s t i c a c i d 2 . 0 X 1 0 ' 2 2 0
. 1
2 Borotungstic a c i d 2 . 0 X 1 0
2
2 0 . 1
3 Phosphotungstic a c i d 1 . 8
X
1 0 ' 3 1 9 . 7
4 S i l i c o m o l y b d i c
a c i d
1 . 3 X
1 0 2
1 7 . 6
5
Phosphomolybdic
a c i d 1 1 X
10 6
4 1 6 . 0
Control 6 s i l i c o t u n g s t i c a c i d 1 . 6
X
1 0 1 4 1 6 . 6
7
Borotungstic a c i d
1 . 4
X
1 0 - 1 1 4
1 5 . 4
8 Phosphotungstic a c i d
1 . 2
X 1 0 1 16
1 4 . 2
9 S i l i c o m o l y b d i c
a c i d
7 . 1 X
1 0 - 4 1 8 1 3 . 0
10 Phosphomolybdic a c i d
6 . 5
X 1 0 1 9
1 2 . 1
continuous o eration w ere found t o be
a l mo st i d e n t i c a l
p EXAMPLE
with those
obtained
with t h e s i l v e r - l i n e d r e a c t o r .
Fur
thermore,
a
gold-lined reactor w a s used i n
s i m i l a r ex
p e r i m e n t s , w i t h
s u b s t a n t i a l l y
t h e
s ame
r e s u l t s .
I n c o n t r a s t
t h e r e t o , w h e n
a
s t a i n l e s s s t e e l
h i g h
p r e s
s u r e
reactor
w a s
emp loyed, t h e r e s u l t s of t h e r e a c t i o n
were
s u b s t a n t i a l l y the
s a m e a s those
o f the
foregoing
e x p e r i m e n t s
d u r i n g t h e
i n i t i a l
p e r i o d . H o w e v e r ,
a f t e r
500
h o u r s
o f
c o n t i n u o u s
o p e r a t i o n , t h e
s i l i c o t u n g s t i c
a c i d i o n c o n c e n t r a t i o n d e c r e a s e d b
y
a p p r o x i m a t e l y
1 0 % , and
t h e S . T . Y . d e c r e a s e d
b y
a p p r o x i m a t e l y
3%.
The i r o n i o n concentration i n t h e s o l u t i o n a t t
h e end of
t h e o p e r a t i o n r e a c h e d 1 8
p pm .
EXAMPLE
P r o p y l e n e was h y d r a t e d t h r o u g h t h e p r o
c e d u r e s a s
i l l u s t r a t e d
i n
t h e
?ow h a r t
o f F I G . 2 .
The
r e a c t o r
and
d i s t i l l a t i o n
co lu mn
were
m a d e
of
s t a i n l e s s
s t e e l ,
with
each
having
an i n n e r diameter o f 2 i n c h e s . The p r o p y l
ene
w a s
preheated and s u p p l i e d i n t o t h e r e a c t o r ( 3
)
t h r o u g h
p i p e ( 1 ) , and w a t e r and c a t a l y s t were i n t r
o
duced t h r o u g h , r e s p e c t i v e l y , p i p e s ( 2 )
a n d ( 4 ) , a t s u c h
r a t e s
t h a t
t h e pH f t h e c a t a l y t i c s o l u t i o n became 2 . 8
-
3 . 0 , and t h e c o n c e n t r a t i o n o f t h e c a t a l
y t i c component
became
2 . 1
X
1 0 3 m o i / l i t e r . The r e a c t i o n w a s
c o n t i n
ued f o r 720
h o u r s ,
a t
280
C .
and
200
kg/cmzG.
The
c a t a l y t i c s o l u t i o n
fr o m
which t h e
r e a c t i o n
product w a s
s e p a r a t e d a t t h e
d i s t i l l a t i o n column
( 6 ) wa s p a s s e d
t h r o u g h a packed tower ? l l e d w i t h c a t i o n
exchange
r e s i n ( t r a d e m a r k , Diaion PK 216)
t o
be removed o f
f r e e
i r o n
i o n s , t h e n
i t s
pH
w as a d j u s t e d
t o
between 2 . 8
-
3 . 0 ,
a n d i t w a s recirculated i n t o the reactor.
The
c o n c e n t r a t i o n
o f
t h e c a t a l y t i c component
i n
t h e s o l u
t i o n
and i s o p r o p a n o l
y i e l d
i n t h e r e a c t i o n
p r o d u c t
a f t e r
720 h o urs o f operation were
a s
s h o w n i n T a b l e ' 3 .
For
comparison, t h e
r e s u l t s
o f t h e r u n s p r a c t i c e d
s i m i a r l y , ( e x c e p t t h a t t h e i o n - r e m o v
i n g column
shown
20
25
30
35
4 5
5 0
The
h y d r a t i o n
i n Run No. 2 o f Table
3
(Example
3 )
w a s
r e p e a t e d e x c e p t
t h a t
t h e
i r o n - r e m o v i n g
column
w a s packed w i t h a c h e l a t i n g i o n exchange r e s i
n (Che
l a t e
R e s i n CD
1 5 , p r o d u c t
o f
MCI).
The r e s u l t s
were
i d e n t i c a l
with
those
of Run No. 2 .
EXAMPLE
The
c a t a l y s t
s t a b i l i z e r s s p e c i ? e d i n
Table
4 were
added t o t h e
c a t a l y t i c
s o l u t i o n s c o n t a i n i n g
s i l i c o t u n g
s t i c a c i d i o n s ( SW) a t
t h e s p e c i ? e d
c o n c e n t r a t i o n s , and
t o each o f t h e
c a t a l y s t
s y s t e m s i s o p r o p a n o l was added
a t
a r a t i o
of
6
w t . o
t h e
t o t a l a m o u n t of
t h e
c a t a l y s t
s o l u t i o n .
The
w h o le
system
w a s poured i n t o a s t a i n l e s s
s t e e l a u t o c l a v e , and a l l o w e d t o s t a n d f
o r
t h e
p r e d e t e r
mined p e r i o d a t
3 0 0 C .
a n d 1 0 0 k g l c m z . The r e s u l t i n g
d e c r e a s e
i n s i l i c o t u n g s t i c
a c i d i o n s
i n
each
r u n
i s
g i v e n
i n Table
4 .
I n t h i s Example, i t
wa s
con?rmed t h a t t h e
f r e e
i r o n
i o n c o n c e n t r a t i o n
i n
t h e
c a t a l y t i c
s o l u t i o n a t
the
end
o f r e a c t i o n
w a s 10
p p m .
For comparison, t h e r e s u l t s of t h e
runs
i n w h ic h
no
s t a b i l i z e r w a s
used are s h o w n
a s Nos.
1
a nd
2 o f
Table
4.
S e p a r a t e l y , 1 5 0 ml
o f
t h e c a t a l y t i c s o l u t i o n w i t h t h e
c a t a l y s t s t a b i l i z e r s i m i l a r l y added
w a s poured
i n t o
a
SOO-ml
c a p a c i t y a u t o c l a v e
equipped
w i t h a
s t i r r e r , and
i n t o w h i ch
ole?n
was added while t h e system w a s
h e a t e d , u n t i l t h e
p r e d e t e r m i n e d t e m p e r a t u r e
a n d p r e s
sure
l e v e l s were a t t a i n e d . The hydration of ole?n
w a s
t h e n
e f f e c t e d f o r e a c h p r e d e t e r m i n e d p e r i
o d . The r e
s u l t s
a r e s h o wn
i n Table
5 .
I n c i d e n t a l l y ,
t h e pH f
c a t a
l y t i c
s o l u t i o n s
wa s a d j u s t e d w i t h
NaOH. I n T a b l e 5 ,
Run No.
6
i s
a n example
i n which t h e s t a b i l i z e r w a s not
added. I t
i s seen f r o m the r e s u l t s o f Run s Nos. 1
6
t h a t
t h e s t a b i l i z e r s do n o t
a d v e r s e l y a f f e c t t h e c a t a l y s t u s e d
i n t h e i n v e n t i o n .
Table 4
C a t a l v t i c
Qnlminn
SW S t a b i l i z e r
Concen- Concen
