Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~ . ~
BACKGROUND OF THE INVENTION
The present invention relates to an improved
process for the hydroalkylation of mononuclear aromatic
hydrocarbons, namely benzene and analogs thereof, to form
cycloaklylaromatics. Many patents have recently issued in
the field of hydroalkylation of mononuclear aromatics. See,
for example, U.S. 3,7605019, U.S. 3,784,617, U.s. 3,784,618,
u.S. 3,829,514, U.S. 3,829,515, U.S. 3,829,516 and U.S.
3,829,517. In the processes disclosed in these patents,
benzene or analog is contacted with a catalyst which is
normally composed of a Group VIII transition metal supported
.. : .
on a suitable carrier, the catalyst optionally containing
tungsten. ~lany different supports are disclosed as useful
including silica-alumina, zeolite and alumina. S~eci~ic
C.~oup VIII transition metals disclosed to be useful are
cobalt, nickel, ruthenium, rhodium, palladium, iridium~and
platinum. -
- ''
, . . . . .
.: . ,.
~ : :
:: : '' - : , :
, . : " : :. - ,
,. . ~ .. , : . ,: '
, . : . . ,
~83609 ( 4~79)
Although processes disclosed in the foregoing
patents are caoable of effecting hydroalkylation of benzene
and analogs to the corresponding cycloalkylaromatic com-
pounds, they are disadvantageous in that they are unable to
provide the desired cycloalkylaromatic product comoounds
. ,
with high yields and high selectivities. ~loreover, in many
processes it is necessary to sub~ect the catalyst to be used
to an activation pre-treatment by reducing the catalyst with
H2 prior to beginning the hydroalkylation reaction. In
still other processes, it is necessary to carry out the
hydroalkylation reaction in stages, the total amount of
hydrogen necessary to effect hydroalkylation being added to
the reaction system in stepped additions.
Accordingly, it is an ob,;ect of the present
invention to provide an improved process for the catalytic
hydroalkylation of benzene and analogs to the corresoonding
cycloalkylaromatic compounds which produces the desired
product compounds in higher yield and with higher selec-
tivities than processes known prior to the present invention.
It is a further object of the present invention to
provide a hydroalkylation process of the type described
above which can be carried out either in batch mode or
continuously in a single stage operation, i.e. a process
which does not require stepped addition of reactants.
It is still another object of the present inven-
tion to provide a hydroalkylation process in which the
catalyst to be used can be employed directly after calcina-
tion, H2 reduction of the catalyst prior to use being
unnecessary.
3609 ( ~979 )
SUMMARY 0~ THE IN~ TI0~
These and other ob~ects are accomplished by the
present invention in accordance with which mononuclear
aromatic hydrocarbons are converted into cycloaklyl aro-
matics by contacting the mononuclear aromatic hydrocarbons
in the presence of hydrogen with a catalyst comprising a
rare earth-exchanged Y-type zeolite support carrying a
promoter comprising at least one of ruthenium, iridium,
rhodium and palladium.
~ ore specifically, the present invention provides
a process for the hydroalkylation of mononuclear aromatic
hydrocarbons in which the mononuclear aromatic hydrocarbon
together with hydrogen is contacted with a catalyst com-
prising a rare earth-exchanged Y-type zeolite support
carrying a ruthenium, iridium, rhodium and/or palladium
promoter, the catalyst being calcined in an oxygen-contain-
ing atmosphere at a temperature of 250 to 600C prior to
the hydroalkylation reaction.
In a specific embodiment, the present invention
provides a process for the hydroalkylation of mononuclear
aromatic hydrocarbons which comprises contacting for a
period of 10 minutes to 6 hours at a temperature of from
room temperature to 400C hydrogen and a mononuclear aro-
matic hydrocarbon selected from the group consisting of
benzene and substituted benzene substituted with 1 to 4
alkyl groups each independently having 1 to 4 carbon atoms
with a catalyst obtained by calcining in a molecular oxygen-
containing atmosphere at a temperature of about 250 to
600C a composite comprising a rare earth-exchanged Y-type
eolite support impregnated with at least one compound
decomposable to yield a promoter comprising at least one of
\
1~36~9 (1~979)
ruthenium, iridium, rhodium and palladium, the amount of the
decomposable co~.pound on the support being such that the
amount of promoter on the support after calcination is
between about 0.2 and l0 weight percent with the weight of
the rare earth-exchanged Y-type zeolite plus the weight of
the promoter being taken as 100%.
In accordance with the present invention it has
been found that cycloalkylaromatics can be produced with
higher yields and higher selectivities than previously known
processes ~or hydroalkylation of benzene and analogs. ~or
example, it has been found that cyclohexylbenzene can be
obtained with per pass conversions approaching 50~ at
selectivities close to 80%, which is significantly better
than obtainable with the prior art processes disclosed in
the above-noted patents. rnoreover, the inventive process
can be accomplished in a single stage operation, i.e.,
without the stepped addition of reactants and hence is
easier to carry out than conventional processes carried out
in multiple stages. .~lso, the catalyst employed in the
inventive process can be used directly after calcination
without H2 reduction, and hence practice of the inventive
process is easier than conventional processes requiring H2
reduction as part of the catalyst preparation.
DETAILED DESCRIPTION
Process Conditions
The inventive hydroalkylation reaction is accom-
plished by contacting the mononuclear aromatic hydrocarbon
to be reacted with a reaction catalyst in the presence of
hydrogen. The reaction can be accomplished both in batch
mode and continuously with both fixed and fluid catalyst beds.
The reaction is normally carried out in single stage
~836~ ( 4979)
operation, i.e., all of the reactants and the catalyst
necessary for the reaction are brought together at the same
time and not in stepped additions. However, the reaction
can be carried out in stages if desired.
The reaction temperature is normally maintained
between room temperature and 400C, preferably 100 to 300C,
more preferably 150 to 250C and optionally 200C. The
reaction pressure is normally maintained at 100 to 800 psig,
preferably 200 to 500 psig and most preferably 300 to 400
psig. When the reaction is carried out in the batch mode,
the reactants and catalysts are contacted with one another
for a period of 10 minutes to 6 hours, preferably more than
1/2 to 3 hours, and optionally about 1,5 hours. A reaction
time of less than 10 minutes or more than 6 hours can be
used if desired although better results will be obtained if
the reaction time is maintained within this range. When the
process is carried out on a continuous basis, the reactant/
catalyst contact time is normally 10 seconds to 10 minutes,
preferably 100 seconds to 5 minutes.
The amount of hydrogen in the reaction system is
not critical, and the reaction will proceed so long as any
amount of hydrogen is present. Preferably the amount of
hydrogen correspond to the amount of hydrogen present when a
600 cc reactor containing 5 grams of catalyst and 2.0 moles
of benzene is filled with hydrogen to the pressures indicated
above. If desired, a carrier gas which is inert to the
reactants, product and catalyst can be included in the
reaction system.
~ 3 ~ ~ (4979)
,
The present invention finds wide applicability in
the hydroal~ylation of all types of mononuclear aromatic
hydrocarbons. Benzene (unsubstituted) and substituted
benzene substituted with 1 to 4 alkyl groups each indepen-
dently having 1 to 4 carbon atoms can be readily converted
to the corresponding cycloalkylaromatics in accordance with
the present invention. Specific examples of compounds which
can be processed by the present invention include benzene,
ethylbenzene, cumene (isopropyl benzene), toluene, xylene,
and durene (tetramethylbenzene).
In order to recover the product compound from the
reaction mixture when the reaction is completed, the liquid
reaction product is separated from any unreacted hydrogen
and carrier gas that may be present in the system. The
liquid reaction product is then filtered to remove catalysts
therefrom and the filtrate is sub~ected to distillation or
other suitable separation technique to recover the product
compound from unreacted starting material.
CATALYST
The catalyst employed in the inventlve process
comprises a rare earth-exchanged Y-type zeolite impregnated
with a small but suitable amount of a iroup VIII transition
metal promoter selected from the group consisting of ruthen-
ium, iridium, rhodium and palladium. Y-type zeolite is a
well-known material in the art and described in detail in
Chapters 18-20 of ~eier and Uytterhoeven, MOLECULAR SEIVES,
American Chemical Society, ~1ashington, D.C., copyright 1973.
See also U.S. 39130,007. As well-known in the art, Y-type
zeolite can be treated to accept various types of ions by
impregnating the Y-type zeolite with a solution of the
ions to be accepted. Such a procedure causes an exchange
--6--
83~
reaction to occur, cations in the aqueous solution being
exchanged for cations originally in the zeolite. See column
- 18 of U.S. 3,130,007. The catalyst support useful in the
inventive process is a rare earth-exchanged Y-t~pe zeolite
which is produced by exchanging rare earth ions from an
aqueous solution thereof with the ions originally in Y-type
zeolite. This material is well-known as pointed out in
columns 7 and 8 of U.S. 3,78~,617. In the preferred embodi-
ment of the invention, the rare earth-exchanged Y-type
zeolite employed in Linde's SK-500 ~, which is a well-known
commercially available catalyst support. Linde's SK-500 is
composed of 65.0 weight percent SiO2, 22.7 weight percent
A12O3, 1.6 weight percent Na2O and 10.7 weight percent
various rare earth metals. Rare earth-exchanged Y-type
zeolites other than Linde's SK-500 can be employed in the
present invention, the specific rare earth impregnating the
Y-type zeolite being unimportant. In this connection, since
it is expensive to separate one rare earth from another,
commercially available rare earth-exchanged Y-type zeolites
are made with mixtures of different rare earths rather than
a single rare earth.
In accordance with the present invention, the rare
earth-exchanged Y-type zeolite employed as the catalyst
additionally contains a promoter metal selected from the
group consisting of ruthenium, iridium, rhodium and palladium.
The preferred promoter is ruthenium. The amount of promoter
metal in the catalyst can vary between relatively broad
proportions. If the amount of promoter metal is about 0.1
weight percent, no significant promoting effect will be
obtained. Moreover, although amounts of promoter metal
about 10% will provide effective catalysts, the cost of
;'
"
,~
~83f~
using such large amounts of promoter metal is prohibitively
expensive. Threfore, the amount of promoter metal in the
catalyst is greater than 0.1 weight percent and usually
between 0.2 and 10 weight percent based on the weight of
promoter metal in the catalyst with the weight of the rare
earth-exchanged Y-type zeolite plus the weight of the pro-
moter metal being taken as 100 percent. Preferably the
catalyst contains 0.5 to 2 weight percent promoter metal,
while the most preferred amount is about one percent by
weight.
In order to deposit the promoter metal on the rare
earth-exchange Y-type zeolite support of the present inven-
tion, any convenient technique can be employed. For example,
the promoter metal in the form of a decomposable salt or
other compound can be dissolved in a solvent therefore and
the solution so obtained used to impregnate the rare earth-
exchanged Y-type zeolite material. Chloride salts (i.e.
Ru~13~3H20, IrC13~4H20, RhC13-3H20 and PdC12) dissolved in
ethanol or isopropanol as the solvent have been found
especially suitable for this purpose. Any other compound
(e.g. nitrates, acetates, etc.) which yield catalytically
active ruthenium, rhodium, iridium or palladium when heated
in the presence of oxygen under the calcining conditions
discussed below can be employed in place of chloride.
Processes for depositing transition metals including ruthe-
nium, iridium, rhodium and paladium,on Y-type zeolite
supports are well-known as taught in U.S. 3,7~1l,617. This
patent further teaches that it is well-known to deposit
other types of Group VIII metals on rare earth-exchanged Y-
type zeolites. Therefore, those skilled in the art should
have no difficulty in producing catalysts including ruthen-
ium, iridium, rhodium and/or palladium on a rare earth-
exchanged Y-type zeolite as used in the present invention.
~1~83609
Once the promoter metal in chloride or other
decomposable compourld form is deposited on the rare earth-
exchnaged Y-type zeolite, the composite so formed is acti-
vated by calcination. In accordance with the present
invention, calcination is accomplished in a molecular
oxygen-containing atmosphere at a temrerature of about 250
to 600C, preferably 350 to 500C, most preferably 427C.
Temperatures below 250C can be employed but activation is
so slow that such temperatures are impractical. At tempera-
tures above 600C, the zeolite support will begin to de
compose hence reducing the catalytic activity of the catalyst
produced. Calcination has the effect of expelling water
from the zeolite support, which in turn causes the calcined
catalyst obtained to exhibit a superior catalytic activity.
Therefore, calcination should be carried out for a time
sufficient to drive off water from the zeolite support and
hence improve the catalytic activity of the catalyst ob-
tained. Those skilled in the art can determine the optimum
calcination time by simple routine experimentation. In this
connection, it has been found that at the preferred calcina-
tion temperature of 427C, the calcination time is approx-
imately two hours, whereas at the maximum calcination
temperature of 600C calcination should last no more than
about eight hours while at the minimum calcination tempera-
ture of 250C calcination should be accomplished for at
least about 24 hours.
Once the promoter metal-containing zeolite com-
posite of the present invention has been sub~ected to calcina-
tion,i~ can be directly used as the catalyst to effect the
hydroalkylation reaction, reduction with hydrogen gas being
unnecessary.
_g_
979
~1~836~9
~ .s indicated above, the products of the inventive
process, namely cycloalkylaromatic hydrocarbons, are pro-
duced in accordance with the present invention with high per
pass conversions and high selectivities. mhus the present
invention marks a significant advance over prior art pro-
cesses since it is possible to produce more end product with
a given amount of feed. rloreover~ with superior select-
ivities, recycle requirements are reduced, thereby decreasing
energy costs. Also, because hydrogen reduction of the
catalyst prior to use is unnecessary, and because the
inventive process can be carried out in single stage opera-
tion the inventive process is simpler to accomplish than
many analogous prior art processes.
The end products of the inventive process, namely
cycloalkylaromatic hydrocarbons, have many significant uses.
For example, these compounds can be converted to phenol
and/or cyclohexanone in the case of benzene and analogous
products in the case of benzene analogs, which compounds
have known utilities.
Working Examples --
In order to more thoroughly illustrate the present
invention, the following working examples are presented. In
these examples "% ppc" reans percent per pass conversion and
is defined as
% _ moles carbon in reactant converted to product x lOC
ppc moles carbon in reactant fed
--10--
(4979)
1~3 6
Example 1
Q.13 gra~. IrC13 4~ as dissolved in 200 cc
distilled water to form a green solution. 9. 9 grams I.inde's
SK-500 (<50 mesh powder) was added, and the water was e~1ap~
orated from the composition so obtained to form a light
brown paste which was dried overnight at 110C to form an
essentially white material. This material was then calcined
in air at 427C for 2 1~ hours to produce a grayish-white
catalyst containing 1~ Ir and 99% SK-500.
5 grams of the catalyst so obtained were charged
into a 600 cc PA~P autoclave. 156.22 grams ( 2.0 moles)
benzene was also fed into the reactor. The autoclave was
then pressurized with hydrogen to a pressure 400 psig. The
reaction progressed for approximately 35 minutes over which
time the pressure in the reactor decreased from 400 to 180
psig and the reaction temperature increased from an initial
value of 22C to 185~. After the 35 minute reaction
period, the reaction product was recovered from the reactor
and subjected to analysis by gas chromotography. The follow-
ing results were obtained:
~pp c
cyclohexane 8.36
bicyclohexane0.10
cyclohexylbenzene 43.94
dicyclohexylbenzene 0. 52
unreacted benzene 47.09
selectivity 83.oo
(4979)
~83~
Example 2The procedure of Example l was repeated except
that catalyst employed was com osed of l" Rh and 99i SK-500.
This catalyst was prepared in the same way as the catalyst
employed in Example l except that 0.256 grams RhCl3~3H2o
was employed rather than 0.193 ~rams IrCl3~4H20. Also, in
Example 2, the reaction time was l '-~ hours rather than '~
hour. The following results were obtained:
~ ~pc
cyclohexane32.51
bicyclohexanel.~,0
cyclohexylbenzene 35.78
dicyclohexylbenzene 0.52
unreacted benzene ll.40
selectivity 40.4
Example 3
Example 2 was repeated except th~t the catalyst
employed contained 1% Pd and 99% SK-500. The catalyst of
Example 3 was prepared as the catalyst of Example l was
prepared except that 0.167 grams PdCl2 was employed. lhe
following results were obtained:
, ppc
cyclohexanelO.74
bicyclohexaneO.lO
cyclohexylbenzene 50.44
dicyclohexylbenzene 4.43
unreacted benzene 33.46
selectivity75.80
~`
. -12
(4979)
1~8360~
Exam~le 4
-
U. S. Patent 3,7849617 to Suggitt discloses a
process for the catal~tic hydroalkylation of mononuclear
hydrocarbons in which the catalyst may be ruthenium sup-
ported on NH4-exchanged Y-zeolite. ~his Example 4 as well
as the following Comparative Exam~les A, B and C are
presented to show the improved results realized in accord-
ance with the present invention when the catalyst is com-
posed of ruthenium supported on rare earth-exchanged Y-
zeolite.
1.056 grams RuC13 3H20 was dissolved in 200 cc of
isopropanol to form a red-brown solutlon. 39.6 grams
Linde's SK-500 was added to this red-brown solution, and the
solvent was then evaporated with constant stirring at low
heat. The green paste formed thereby was dried overnight at
110C in an oven to produce a gray powder. A portion of
this gray powder was calcined at 427C for 2 hours in the
presence of air to provide the Example 4 catalyst having 1,~
Ru and 99% SK-500.
Hydroalkylation of benzene was carried out in the
same way as in Example 1 except that the reaction pressure
was maintained at about 300 psig and the reaction tempera-
ture was maintained at about 200C. Also, a portion of the
liquid reaction medium was withdrawn at '~ hour intervals and
the composition of each withdrawn portion determined. The
following results were obtained:
108360~
~ . :
.~ ~:.
.,,
. . . "
~, o ." ~ ~9
) I` I`
U~ . :
,
U~
,~ ~ `'
~o ~ ~ ~
X . ~ N . . ~ O
' ~ ~ ~ ~ ~ O ~:
S-l (I) O;) ~ d' ~
~ m
o P
4~
:~ .
04~J N ~~;r :
P:~ I` o
C~. . . :~
.~O ~ 1~
.,:
S~ O .~, :-
.~ ~ ~ I~ t~
~ ~ ~ " O ,.'. ,
o~o O ~ ~i
.~ ~1 ~ ~r
.~ . Z ~ ~r . , :, ,
U P~ ~ ~ '. -,~ ,.
o o o o o
~i o m
O
.1
K zic5~Lr~
u~ ~C ~ o
o\O , ~ o ~
a~ :,
-.
~ :
o~O _~ ~1 .~ .
. I O
a) u~ ,~
~ s~ O ~ .
.. ,~ ~~ O ~ .
E~ ~ ~1 ~1 0 ,. :
~Q ~ ~ ~ ~::
~ ~1
f~ ~ ~ trl i
~
0 ~ rl
.
i
~1
:: ~
:
1~8360~
Comparative Example A
Example 4 was repeated except that the catalyst
employed was composed of 1~ Ru and 99% NH4-exchanged Y-
zeolite which was calcined at 427C for 2 hours. The
following results were obtained:
-15-
:
~836~)g
.~ ".
~ In ~ ~ ~ `,'~:
U~ ~
,~ C) ,~ ~ ~ ~ ,.
~ 0~ 0~ 1~ ~D '.
o ,,
$ ~
U~ ,
:~
o
a~
C) ~ ~ ~ ~ I~
O c~ a)~r ~ I~ :
1~ (~ N . . . ,
t~ O ~ ~D 1~ ~ ~1
~ m
s~ ;,,:
u ,~ o ~r o
~1 ~1
n ~ ~r 1~ cO
,0 m
,~ m
~ ~ O o ~r o o ~;
~ .~ ~ u~ Ln
~ o ~ ~ ~
~1 ~ C) o O O o
~ ~ i:q ?
., o ~ ~; ~ ~ 00
C~ ~ $ r- o c
X ~
, ~ ~,
~r
m a)
z ~ :,
0~O ~ ~
.
I o
O h ~1
~`I o ~
~1 ~ ~ ~ O f~ :
E~
IY; ,1 ~1
~ S~
o'~O
.
..
~ .
O
Z
E~ -:
~i ~ ~ ~ ~
a)
-- 16 --
(4979)
~83~)9
Comparative Example B
A portion Or the gray powder produced during
catalyst preparation in Example Ll was prepared for use in
accordance with the technique disclosed in U. S. Patent
3,829,517. Namely, the gray powder was calclned at 800C
for 2 hours in the presence of air ancl then reduced with H~
at 480C at atmospheric pressure for 2 hours. Example 4 was
then repeated using this catalyst. The following results
were obtained:
,
:
836
p
.~ Ln ~ ~ ~ :
o ~ o l` ~
~ ~ ~ oo oo
:~ :
u~
~ :
a) tl)
Ul ~ ~9 ~1 -~
o a~ cO r- c~ ~9
U~IT~ N
~ h
o ~:5~ O 0~ 00 1
O o ~m
O X ~
~ s~ ~.
o m
~ ~ ~ ~ ~ I
~1 C~ ~ ~ N ~D
~) ~ . . .
o ~ o O ~ ~
,1 0~ t)
~r
m
~ m ~ ~ ,
~~ ~ 0\o ~
,~ C~ ~, ~ O O
4O ~ r-l ~1 ~ N
~~X
~q
r~.,,
o ~ ~ a) ~ a) '
!~~ x c~
I O C) O
~ K m
O~ ~ Z ~D ~ O CO
C~~ ~ ~ n ~ ~ r~ ,
E~ ~
o o ~ ~
~ o ~ :`
u~
:
l o
ra O ~ ~ .
r
d O E~ ~ ~ N
~ ~ ~ S~
rl
~_ ~1
t~
.
: "~ .
O ''
Z;
.~
s~ m m m m
~C
; ~ ~:
-- 18 --
1~9831~
Comparative Example 5
Example 4 was repeated except that the catalyst
employed was composed of 1% Ru and 99~ NHLI-exchanged Y-
zeolite, the catalyst having been calc:ined at 800C for 2
hours in the presence of air and thereafter reduced at 480C
in the presence of H2 for 2 hours in accordance with the
technique taught in U. S. Patent 3,829,517. The following
results were obtained:
--19--
3609 ~
.
,
P ".~
~ ~r ~ o ~
U
a) ~ 1- ~ ~
:.
~q :~
C~ :`::
o :
CO
.,. ~ ~ oo
c) a~ ~9 ~ ~ ~
td N : :
~Q ~ ~ . ~ ~D
s~ ~ a)
.,, ~ ~m
V m ~ :
o ~
s~ m
o m
,~ ~ C~ U~ ~ O O :
~1 . . . . --
o
a~
u~
Q ~:q ~ 1` ~ ~1
1:~1 ~ ~ ';~
~ ~ a~ 0~o ~ ~ ~ o~ In
~! ~ ~1
~ ~ ,~
X Z [`I`
:~ ~ I ~ ~mq ~ N
H d'~ t) O O O O
~j Z; E~ m ~ .
,. ~ 0O~ ,.
o Ul Z; O
~ ~ ~1 ~C
m
,~ o C~ ~ Ln 1` C~ S
~ m ~ .
0~O ~
~ ~.
o
.. 4~ ~d
~1
C~
~, O . I o
O
O ~ 5~ o ~
o ~ . .
E~ ~ ~ U
~1 ~ 5
_
s~
.,, ~ ~:
td~
H
:' Z
:
~ ~1
:` ~
X
~: ' '
- 20 -
,.~ .
~;
(4979)
36~9
Comparative Example D
U. S. Patent 3,829,517 to Zuech discloses a
catalytic hydroalkylation process employing a ruthenium
halide-active clay catalyst which has not been heated under
calcination conditions prior to use. This Comparative
Example D as well as the following Comparative Examples E
and F are presented to show the superiority of the inventive
process as illustrated in Example 4 with respect to the
process shown in U. S. 3,829,517.
o.7895 grams RuC13 3H20 was dissolved in 200 cc
ethanol to produce a dark red-brown solution. 29.7 grams
Filtrol Grade-71 powder was suspended in the solution and
impregnated at low heat with constant stirring. The solvent
was then removed and the wet powder obtained dried in an
oven at 110C for 3 hours to produce a gray powder. A
portion of the gray powder was calcined at 427C in the
presence of air for 2 hours in the manner of Example 4 to
yield a catalyst containing 1% Ru and 99% Filtrol Grade-71,
which was employed as the catalyst in Comparative Example D.
Example 4 was repeated using as the catalyst the
catalyst obtained above. The following results were obtained:
~ !
1(~836(~
u7 ~ ~ a~
~D ~ ~ U)
a) o~ 00 a) ,
~, ~
U~
~r
a) a
~ ~ o ~r
U~ ~, ~ ~ ~ o
(1~ N
:1 a~ ~ O 1
o ~ a~ ~ ,~
m ~ m
::~
s~ :
o m O
P:l
s~ o
.,~ ~,1 O O ~1
a
~ o
~ 0~ ~ ~ ~
a ~ ~ ~
co a~ ~ ~1
.,1 ~ ~ ~ :.
u ~q a~
m
C~ ~ . .
~ a) ,~ ~ o o
E~ ~ ~ ~ ,.
~ ~ æ ~ O ~ ~,
o o ~ O ~ O ~
c~ s~ m
C)
.~
0~O ~ .
~ ~ .
a~ ~ .
~ ~ C)
I o
O ~ .
~ O n~ ~ ~
o~ ~ ~ ~ c)
~1 ~ ~ \ ~ :
'1.
..
u~ ~ ~1
'.
., t~ O
æ
~:
. ~ ~ ~ ~ ~P
~: ~ a a a a
, X
:. :
:.
-- 2 2
~3609( 4979)
Comparative Example ~
Example 4 was repeated using as the catalyst a
portion of the gray powder produced during catalyst prepara-
tion in Comparative Example D. It will be noted that this
catalyst was composed of 1~ Ru and 99% SK-500 and was not
calcined prior to use. The following results were obtained:
.
:
83~9
.~
~1 ~ ~D CO
C~ ~ ~ ~`
I~
~n
..
~ ~ `,.
O (U ~X) Il ) N 00
(d N ~0 N
~ a
p m a~
m ,~ N O
m
rl ~)
C) ~1 O O O :`
..
N N 00
1 ~4 t`
O P~
P O O O ~--1 1~ N N
~ Il~ ~ ~I r-l ~
~ , ~ ~ .',
1~1 U~ o\O ~.
~ O~o x a) :,.,
~ ~ X O O O
C~ ~ Z O ~ CO CO
X ~ ~) t~
o ~ r~
~q
~ .
U~ I ~O)
a
~ O
rl N O t~
E~ ~ ~ N ~ :
.,1 ~1 ~1 ~ ~ '
_. ~ S ~
a) ~ .
,~
.
~ O ,
: Z :
O ' ':
a)
r I N ~) 'r
., ~1
:: ~
Q~
' X
.
_ 24 --
.
~1~8361~9
Comparative ~xample ~
Comparative Example D was repeated except that the
catalyst was not calcined prior to use. It will thus be
appreciated that the catalyst employed in this co~parative
example was composed of 1~ Ru and 997 Filtrol ~rade-71, the
catalyst bein~ uncalcined as taught in U. S. 3,829,517. mhe
followlng results were obtained:
'~,':,,
1~3~
rl
.,. CO CO
~, o ~ ~
~ I~ 0~ 00 1
U~
a
,~
aJ ~ ~ 1~ ~r ~
s~ a) ~ , 00 ,0
p m
'u
:
m O O O O
o ~
~` ~ ::
:~:
o ~r '
s~ m ~ O
m
~ o o O ~ ~ ~
H o\ q O O O O
~ ~ m
~ Z
C_) P:; X N t~l ~ ~
0~ m O O O O
..
..
:
~1
~ .
,. ~ tn I O
,.
o ~
\ ~ O 0
rl
.. ~ ~
;', ~ rl
.; .
~: ~o;
~:
,1 ~I N ~) ~
: ~ ~
'
-- 26 --
