Title of Invention

CATALYST FOR CYCLOOLEFIN PRODUCTION AND PROCESS FOR PRODUCTION

Abstract A catalyst for production of a cycloolefin by partial hydrogenation of a monocyclic aromatic hydrocarbon, wherein the catalyst comprises zirconia as a carrier, and particles having an average primary particle diameter in a range of from 3 to 50 nm and an average secondary particle diameter in a range of from 0.1 to 30 µm.
Full Text The present invention relates to a catalyst
for production of cycloolefins by the partial
hydrogenation of a monocyclic aromatic hydrocarbon, a
process for production of the catalyst and a process
for production of cycloolefins. Specifically, the
present invention relates to a catalyst for production
of cycloolefins, formed so that the catalyst comprises
zirconia as a carrier, and has an average primary
particle diameter from 3 to 50 nm and an average
secondary particle diameter from 0.1 to 30 µm.
Additionally, the present invention relates to a
process for production of the catalyst and a process
for production of cycloolefins, characterized in that
the catalyst is used for the partial hydrogenation in
the liquid phase of a monocyclic aromatic hydrocarbon
in the presence of water.
[BACKGROUND ART]
[0002]
Conventionally, a ruthenium catalyst has
generally been employed as the catalyst for producing

cycloolefins through the partial hydrogenation of a
monocyclic aromatic hydrocarbon. Further, for such
ruthenium catalysts, processes typically used water and
a metal salt. As production processes using a well-
known catalyst, examples of processes which carry out a
reaction by using fine particles of ruthenium metal
unchanged are disclosed in patent documents 1 to 3.
Examples of processes which carry out a reaction by
adding at least one kind of metal oxide in addition to
fine particles of ruthenium metal are disclosed in
patent documents 4 to 6. Examples of processes which
employ a catalyst supporting ruthenium on a carrier of
silica, alumina, silica-zirconia and the like are
disclosed in patent documents 7 to 10. Additionally,
an example of a process which employs a catalyst
supporting ruthenium on a mesoporous silica material is
disclosed in patent document 11.
[0003]
The conventional processes, however, have a
number of problems. In the case of carrying out a
reaction by using fine particles of ruthenium metal
unchanged as the catalyst, or the case of carrying out
a reaction by adding at least one kind of metal oxide
in addition to fine particles of ruthenium metal,
catalytic activity decreases due to agglomeration of
the catalyst particles in the reaction system. Thus,
cycloolefin productivity is decreased.
[0004]

On the other hand, catalysts having ruthenium
loaded on a carrier of silica, alumina, silica-zirconia
or the like have a problem in that its selectivity for
cycloolefin is very low, although it is initially
highly active with respect to ruthenium. Another
problem exists in that the carrier dissolves under
reaction conditions where water and a metal salt are
present (hydrothermal and acidic). Dissolution of the
carrier causes peeling of the supported active
hydrogenation component from the carrier, which leads
to a dramatic decrease in activity and a drop in
selectivity. An additional problem arises in that the
eluted carrier contaminates the reaction system. For
these reasons, there is a demand for a technology which
can stabilize catalytic performance and stably maintain
the reaction system.
[0005]
[Patent Document 1] JP-A-61-50930
[Patent Document 2] JP-A-62-45541
[Patent Document 3] JP-A-62-45544
[Patent Document 4] JP-A-62-201830
[Patent Document 5] JP-A-63-17834
[Patent Document 6] JP-A-63-63627
[Patent Document 7] JP-A-57-130926
[Patent Document 8] JP-A-61-40226
[Patent Document 9] JP-A-4-74141
[Patent Document 10] JP-A-7-285892
[Patent Document 11] JP-A-2002-154990

[DISCLOSURE OF THE INVENTION]
[Problems to be Solved by the Invention]
[0006]
One characteristic of the present invention
is its use as a carrier of zirconia which does not
dissolve even under the hydrothermal and acidic
reaction conditions that are present in cycloolefin
production. Using a carrier that does not dissolve
allows the carrier to remain as a solid even if the
reaction system is a liquid phase. This is
advantageous in that the reaction system is not
contaminated and that the carrier can be handled easily
when separating/recovering it.
[0007]
Even if a carrier that does not dissolve
under hydrothermal and acidic reaction conditions is
used, physical properties of the catalyst change during
the preparation of the catalyst or under the reaction
conditions depending on the physical properties of the
carrier used. Peeling or agglomeration of the catalyst
component on the carrier may occur, thereby causing a
decrease in activity or selectivity. Furthermore, if
the reaction temperature or pressure is high, the
decrease in catalytic performance increases has a
greater impact. Additionally, the size of the catalyst
or carrier particles influences the reaction
performance of the catalyst as well as dispersion and

handleability.
[0008]
While catalyst dispersion within the reaction
system improves if the catalyst particles are small,
separation and recoverability worsen because the
catalyst particles are so fine. On the other hand,
while separation and recoverability improve if the
catalyst particles are large, the large particles can
cause other problems. Such problems include, for
example, causing a reduction in crushing strength or a
reduction in reaction performance. The support
component for supporting onto the carrier is small in
comparison to the carrier weight. Usually, the size of
the catalyst particles is generally equal to the size
of the carrier. The catalyst for cycloolefin
production according to the present invention, however,
can have its physical properties change depending on
the characteristics that the carrier possesses, as the
catalyst preparation process and employed reaction
conditions are hydrothermal and acidic conditions. For
this reason, it is necessary to define the catalyst
particles. In addition, the carrier must not only not
dissolve under the conditions used, but it must also
possess the physical properties of improving catalytic
performance and being able to stably maintain the
catalyst component on the carrier, as well as being
excellent in handleability.
[0009]

The present invention defines composition
parameters, such as the size of catalyst particles. It
is an object of the present invention to provide a
catalyst for cycloolefin production which possesses
high activity and high selectivity for its catalytic
performance and which also improves catalyst life and
handleability through the use of a defined carrier.
[Means to Solve the Problems]
[0010]
As a result of earnest research for achieving
the above-described object, the present inventors have
found that the below-described catalyst exhibits high
performance in the areas of activity, selectivity, life
stability and handleability during production of a
cycloolefin by partial hydrogenation of a monocyclic
aromatic hydrocarbon. Based on this finding, the
present inventors have completed the present invention.
That is, the present invention is directed to the
following:
[0011]
(1) A catalyst for production of a cycloolefin by
partial hydrogenation of a monocyclic aromatic
hydrocarbon, wherein the catalyst comprises zirconia as
a carrier, and particles having an average primary
particle diameter in a range of from 3 to 50 nm and an
average secondary particle diameter in a range of from
0.1 to 30 µm.
(2) The catalyst according to the above-described

(1), wherein the catalyst has an average pore diameter
in a range of from 2.5 to 15 nm, and a pore volume in
the 2.5 to 15 nm range of the pore diameter is 50% by
volume or more of the total pore volume having pore
diameters from 2 to 150 nm.
(3) The catalyst according to the above-described
(1) or (2), wherein the catalyst contains ruthenium.
(4) The catalyst according to the above-described
(3), wherein the average crystallite diameter of the
ruthenium is from 2 to 15 nm
(5) The catalyst according to the above-
described (3) or (4), wherein the catalyst comprises
zinc or a zinc compound.
(6) The catalyst according to any of the above-
described (1) to (5), wherein the catalyst has a
specific surface area in a range of from 20 to 300 m2/g.
(7) The catalyst according to any of the above-
described (1) to (6), wherein the carrier is an
interstitial-pore type porous zirconia material formed
by assemblage of the primary particles.
(8) The catalyst according to the above-described
(7), wherein the carrier is a hafnium oxide-containing
zirconia.
(9) A production process of a catalyst for
producing a cycloolefin by partial hydrogenation of a
monocyclic aromatic hydrocarbon, wherein a porous
zirconia material serving as a carrier is constituted
from particles having an average primary particle

diameter in a range of from 3 to 50 nm and an average
secondary particle diameter in a range of from 0.1 to
µm.
(10) A production process of a cycloolefin by
partial hydrogenation of a monocyclic aromatic
hydrocarbon, comprising partially hydrogenating the
hydrocarbon in liquid phase in the presence of water,
by using the catalyst according to any of the above-
described (1) to (8) .
(11) The production process according to the
above-described (10), wherein a zinc compound or a zinc
ion, or both, are present in the liquid phase.
[EFFECT OF THE INVENTION]
[0012]
An active hydrogenation catalyst according to
the present invention is supported on a zirconia
carrier. The catalyst is characterized in that the
particle diameter of the catalyst is defined. Unlike
conventional catalysts, the present catalyst exhibits
excellent performance. For example, there is no
dissolution of the carrier under hydrothermal and
acidic conditions, or conferral of a positive influence
on diffusion within the catalyst of the cycloolefin
undergoing reaction. Additionally, the catalyst has
the ability to suppress peeling and agglomeration on
the carrier of the supported active hydrogenation
component. The present catalyst also improves

handleability during separation and recovery of the
solid catalyst. In comparison with conventional
catalysts, using the active hydrogenation catalyst
according to the present invention allows for the
stable production of cycloolefins having high activity
and high selectivity over a long period of time.
[BEST MODE FOR CARRYING OUT THE INVENTION]
[0013]
The present invention will now be described
in detail.
The active hydrogenation catalyst according
to the present invention uses zirconia as a carrier,
and has catalyst particles in which the primary
particles have an average particle diameter of 3 to 50
nm. The secondary particles formed therefrom have an
average particle diameter of 0.1 to 30 µm. More
preferably, the primary particles have an average
particle diameter of 4 to 20 nm, and the secondary
particles formed therefrom have an average particle
diameter of 0.2 to 10 µm.
[0014]
The catalyst according to the present
invention uses zirconia as the carrier because
zirconia materials are very durable.
[0015]
"Catalyst average primary particle diameter",
as used in the present invention, indicates the average

size of the single particles contained in the catalyst
and the carrier. In addition, "average secondary
particle diameter" refers to the size of a mass of
agglomerated primary particles, and indicates the
average value of the size of what is usually called an
"agglomerate". The primary particles of the catalyst
according to the present invention are formed from a
granular catalyst component and single zirconia
particles, and secondary particles are formed from
those primary particles.
[0016]
The size of the particles constituting the
catalyst is an important design matter for improving
the reactivity and stability of catalytic performance.
The size of the particles also strongly influences the
handleability of the catalyst. A catalyst structure
defined by primary particle diameter and secondary
particle diameter can control the pores of the catalyst
from its structural characteristics. Such pore
function improves the reaction selectivity of the
desired product. For example, it exerts a positive
influence on substance mobility of the reaction
substrate. In addition, a catalyst in which the
primary particle diameter and secondary particle
diameter are defined according to the present invention
exhibits greatly improved activity and catalyst life
performance. For example, a catalyst in which the
primary and secondary particle diameters are defined

according to the present invention has high dispersion
of the active catalyst component, securely fixes and
holds the active catalyst component on the carrier,
allows the active catalyst component to act
effectively, and suppresses sintering of the active
catalyst component.
[0017]
If the catalyst average primary particle
diameter is less than 3 nm, agglomeration of the
catalyst tends to occur under hydrothermal and acidic
conditions. Furthermore, agglomeration of the zirconia
particles used as the carrier tends to progress, and
the specific surface area of the catalyst decreases.
The active catalyst component then becomes contained
within the carrier, and single-particles, mobile
agglomerates and the like form. As a result, the
stability of the catalytic performance cannot be
maintained. If the catalyst primary particle diameter
is greater than 50 nm, the active catalyst component
supported on the carrier and the co-catalyst component
for improving selectivity tend to move. These
components may form mobile agglomerates, causing
catalytic activity and selectivity to deteriorate.
[0018]
If the catalyst average secondary particle
diameter is less than 0.1 Jim, suitable pore volume and
pore structure cannot be maintained. The active
hydrogenation component supported on the secondary

particle surface is thus exposed, causing a
deterioration in catalytic activity and selectivity.
Furthermore, handleability, such as separation and
recovery of the catalyst, worsens. Increasing the
catalyst secondary average particle diameter to more
than 30 µm results in a negative impact on intra-pore
diffusion of the reaction substrate during cycloolefin
production, and reactivity deteriorates. Furthermore,
problems with catalyst shape-stability and
handleability also occur. For example, the catalyst
becomes more susceptible to pulverization under the
conditions used.
[0019]
The catalyst according to the present
invention exhibits an advantageous effect wherein the
particle diameter of primary particles and secondary
particles which constitute the catalyst control
movement of the substrate undergoing reaction within
the catalyst. Additionally, the particle diameters
also play a part in fixing the active catalyst
component in the catalyst on the carrier. The
geometrical action which occurs when primary particles
agglomerate to form a secondary particle realizes high
selectivity and high activity, while suppressing
peeling, movement and agglomeration of the supported
active catalyst component. Thus, the catalyst particle
diameters improve stability. Further, if the catalyst
particle diameters have the physical properties of said

range, additional effects are produced. For example,
it is more difficult for the secondary particles to
fragment under the conditions used, the catalyst
sedimentation rate increases, and the carrier is more
easily separated and recovered from the reaction layer.
[0020]
In the present invention, although the
primary particle diameter of the catalyst is defined in
terms of average particle diameter, the catalyst
primary particles need not be particles of a uniform
size, and particle size distribution is not restricted.
The particle size distribution of the primary particles
can be broad, and the particle size distribution does
not have to be uniform. For example, particles having
a primary particle diameter of 30 nm or more and
particles having a primary particle diameter of 4 nm or
less can be mixed together.
[0021]
The pore structure of the catalyst according
to the present invention possesses an average pore
diameter in the range of from 2.5 to 15 nm. The pore
volume in this pore diameter range is such that the
catalyst is preferably 50% or more, by volume, of the
total pore volume of pore diameters 2 to 150 nm. More
preferably, the catalyst possesses an average pore
diameter in the range of from 3 to 10 nm, and the pore
volume in this pore diameter range is such that the
catalyst is preferably 50% or more, by volume, of the

total pore volume of pore diameters 2 to 150 nm.
[0022]
Pore characteristics of a supported catalyst
have an effect on control of particle growth of the
supported active hydrogenation component.
Additionally, the pore characteristics influence intra-
pore mass transfer of the raw material substances and
generated product during the reaction. If the average
pore diameter is 2.5 nm or less, however, mass transfer
of the reaction substrate does not occur effectively.
As a result, selectivity and activity tend to
deteriorate. Further, this very often leads to a
situation where the active hydrogenation component is
not stably dispersed on the carrier, and catalyst life
is shortened. If the average pore diameter is larger
than 15 nm, the active catalyst component loaded in a
dispersed state sinters because of high-temperature and
hydrothermal conditions or similar. This large pore
diameter is unfavorable because it results in decreased
activity. Preferably, pore distribution is narrow and
uniformwithin the distribution range.
[0023]
The present invention may support a metal or
a metal compound, or a mixture thereof as the
hydrogenation active catalyst component on the zirconia
carrier. Components capable of hydrogenation catalysis
are well-known in the conventional art. Ruthenium is
particularly preferable among hydrogenation active

catalyst components.
[0024]
"Ruthenium", as mentioned in the present
invention, includes ruthenium metal, ruthenium
compounds and the like. It is used under conditions
including a metal or a charged state, or a state
possessing both characteristics. The average
crystallite diameter of the supported ruthenium is
preferably from 2 to 15 nm, as this diameter of
ruthenium results in improved stability in the carrier
pore interior. With an average crystallite diameter of
less than 2 nm, movement within the carrier pores tends
to occur, and agglomeration of the active hydrogenation
component progresses. As a result, catalytic
performance cannot be stably maintained. If the
average crystalline diameter exceeds 15 nm, dispersion
is poor, and activity with respect to the active
catalyst component is also poor. Thus, the size of the
pore diameter and active component being of the same
order as that of the catalyst primary particle diameter
improves the stability and activity of catalytic
performance.
[0025]
The amount of ruthenium supported on the
carrier is preferably in the range of 2 to 30% by
weight of the carrier weight converted into ruthenium
metal. It is more preferable 'to have an amount of
ruthenium in the range of from 4 to 22% by weight. The

amount of ruthenium most preferable is in the range of
from 8 to 18% by weight. If the amount of ruthenium is
under 2% by weight, although activity increases with
respect to active catalyst component, activity with
respect to catalyst deteriorates. Thus, the total
catalyst content, including the carrier, has to be
increased. While the amount of the active catalyst
component actually used can be decreased, this is not
preferable. When the amount of active catalyst
component is decreased, the catalyst becomes more
susceptible to the impact of toxic substances stemming
from the raw materials or the reactor material. On the
other hand, if the active hydrogenation component
exceeds 30% by weight, it becomes more difficult to
carry out uniform support in practice.
[0026]
The present invention can use, as a component
which is supported on the carrier, ruthenium alone, or
another co-supported metal component in addition to
ruthenium. Examples of raw materials for the ruthenium
supported on the carrier include halides, nitrates and
hydroxides of ruthenium, ruthenium carbonyl and
ruthenium complexes such as ruthenium amine complexes.
[0027]
Further, examples of the component which can
be used for co-supporting with ruthenium include zinc,
nickel, iron, copper, cobalt, manganese, alkaline-earth
elements, and rare-earth elements such as lanthanum,

cerium, samarium and terbium. The raw material for
these examples includes the various compounds of the
co-supporting component, such as halides, nitrates,
acetates and sulfates of the respective metal, and
complexes containing the respective metal. These co-
supporting components with ruthenium provide effects in
reaction activity and selectivity performance of the
catalyst. Additionally, they have an effect on the
stability of catalyst life. Among them, zinc is a most
preferable co-supporting component. Preferably, the
content thereof is 5 moles or less of zinc atoms per 1
mole of ruthenium atoms, and the range of from 0.01 to
3 moles is particularly preferable.
[0028]
The specific surface area of the catalyst
according to the present invention is preferably in the
range of from 20 to 300 m2/g. A specific surface area
in the range of from 30 to 150 m2/g is more preferable,
and the range of from 50 to 120 m2/g is most preferable.
To maintain a high dispersion of active hydrogenation
component, a preferable range for the specific surface
area exists. Within that range, the reaction stability
of the catalyst can be maintained.
[0029]
The present invention is characterized by
using an interstitial-pore type porous zirconia
material as its carrier for the catalyst. In the
zirconia material, the average particle diameter of the

primary particles and the average particle diameter of
the secondary particles are defined. The meaning of
"carrier average primary particle diameter", as used in
the present invention, refers to the average size of
zirconia single particles which constitute the carrier.
In addition, "average secondary particle diameter"
refers to the size of a mass of agglomerated primary
particles, and indicates the average value of the
carrier particle size (agglomerate size).
"Interstitial-pore type porous zirconia material"
refers to zirconia comprising a large number of pores
which are formed as gaps between the primary particles.
These pores are produced when the zirconia primary
particles (single particles) agglomerate to create a
secondary particle.
[0030]
The carrier according to the present
invention is an interstitial-pore type porous zirconia
material constituted from secondary particles in which
primary particles have agglomerated. The carrier
serves to disperse the catalyst component, to fix and
hold the catalyst component on the carrier, to allow
the catalyst activity site to work effectively, and
greatly contributes to improving activity and catalyst
life performance by suppressing sintering and the like.
Pore action of the carrier also has a large effect on
reaction selectivity of the desired product, such as by
exerting an influence on substance mobility of the

reaction substrate.
[0031]
When preparing a solid catalyst, the size of
the particles constituting the carrier is an important
design consideration for improving the reactivity and
stability of catalytic performance. Size also has a
strong effect on the handleability of the catalyst.
[0032]
By defining the size of the zirconia primary
particles and secondary particles which constitute the
carrier, the supported active hydrogenation component
exhibits excellent performance. For example, it
suppresses peeling from the carrier and agglomeration
on the carrier. The strength with which the supported
component is fixed to the carrier reflects the size of
the particles which constitute the carrier. The
geometrical action which occurs when primary particles
agglomerate to form a secondary particle contributes to
an improvement in stability.
[0033]
By using a porous zirconia material, which
has its physical properties defined according to the
present invention, as a carrier, catalyst physical
properties can be achieved which approximate the
physical properties of the carrier, and preferable
physical properties as a catalyst can be maintained.
The reason for this is that the porous zirconia
material used in the present invention has high

chemical resistance and is not readily affected by
heat, and the physical properties of the carrier are
not readily susceptible to a large changes due to
subjecting the active catalyst component to the support
process. The particle diameter of the active catalyst
component supported on the porous zirconia material is
minute. Thus, by preparing the amount of component to
be supported in the range of 3 to 30% by weight, the
physical properties of the carrier supporting the
active catalyst component dramatically affect the
physical property values of the catalyst. Therefore,
the primary particles and secondary particles of the
porous zirconia material used as the carrier are
present without great change even after the preparation
of the catalyst. The physical properties, such as
particle size of the catalyst, are approximately the
same value as those of the porous zirconia material
used as the carrier.
[0034]
The carrier used in the present invention is
a porous zirconia material constituted from particles
having an average primary particle diameter of 3 to 50
nm, and an average secondary particle diameter of 0.1
to 30 µm. More preferably, the porous zirconia
material is constituted from particles having an
average primary particle diameter of 4 to 20 nm, and an
average secondary particle diameter of 0.2 to 10 µm.
[0035]

If the average primary particle diameter is
small, agglomeration of the zirconia particles tends to
proceed under hydrothermal and acidic conditions. As a
result, the specific surface area of the carrier
decreases, the catalyst component becomes contained
within the carrier single-particles and mobile
agglomerates and the like form. As a result, the
stability of the catalytic performance cannot be
maintained. If the particle diameter is too large, the
active hydrogenation component loaded within the pore
and the co-catalyst component for improving selectivity
tend to move and agglomerate. This leads to a
deterioration in catalytic activity and selectivity.
Thus, the primary particle diameter influences the
stability of the physical properties of the carrier, as
well as the stability of the component supported on the
carrier.
[0036]
In the present invention, while the primary
particle diameter of the carrier is defined in terms of
average particle diameter, the carrier primary
particles need not be uniform particles, and particle
size distribution of the primary particles is not
restricted. The particle size distribution of the
primary particles can be broad, and the particle size
distribution does not have to be uniform. For example,
particles having a size of 50 nm or more and particles
having a primary particle diameter of 3 nm or less can

be mixed together.
[0037]
On the other hand, if the average secondary
particle diameter is less than the above-described
range, suitable pore volume and pore structure cannot
be maintained. The active hydrogenation component
supported on the secondary particle surface is exposed,
and results in a deterioration in catalytic activity
and selectivity. Furthermore, handleability, such as
separation and recovery of the catalyst, worsens. If
the secondary average particle diameter increases and
exceeds the above-described range, intra-pore diffusion
of the reaction substrate during cycloolefin production
is negatively impacted, and reactivity deteriorates.
Furthermore, problems with catalyst shape-stability and
handleability also occur. For example, the catalyst
becomes more susceptible to pulverization under the
conditions used.
[0038]
The porous zirconia material according to the
present invention is an interstitial-pore type porous
material, having secondary particles formed from an
agglomeration of primary particles. As the pore
characteristics of such porous material, the average
pore diameter is in the range of from 2.5 to 15 nm,
wherein the pore volume in this pore diameter range is
such that the porous zirconia material is preferably
50% or more, by volume, of the total pore volume of

pore diameters 2 to 150 nm.
[0039] Pore characteristics in a supported catalyst
have an impact on controlling particle growth of the
supported active catalyst component, and influence
intra-pore mass transfer of the raw material substances
and generated product during the reaction. While a
carrier for a catalyst component is still feasible when
the average pore diameter is less than 2 nm, this is
not preferable because the intra-pore mass transfer of
raw material substances and the generated product is
restricted, resulting in deterioration in the reaction
activity and selectivity. If the average pore diameter
is large and exceeds the above-described range, the
dispersibly supported catalyst component sinters
because of high-temperature and hydrothermal conditions
or similar. This large pore diameter is unfavorable
because it results in decreased activity. Preferably,
pore distribution is narrow and uniform within the
distribution range.
[0040]
To maintain the catalyst supported amount in
a preferable range, the pore volume of the porous
zirconia material according to the present invention is
preferably a pore volume of 0.1 cm3/g or more per 1 g of
carrier. The pore volume is important in maintaining
the carrier amount of the catalyst component in the
preferable range, and more preferably within the range

of 0.15 to 0.6 cm3/g. Under a pore volume of 0.1 cm3/g,
only a minute amount of the active hydrogenation
component can be supported in the pores. On the other
hand, if the pore volume is too large, the pores and
secondary particles are susceptible to physical
destruction.
[0041]
The specific surface area of the porous
zirconia material according to the present invention is
preferably in the range of from 20 to 300 m2/g. More
preferable is a specific surface area in the range of
from 30 to 150 m2/g, and most preferable is in the range
of from 50 to 120 m2/g. If the specific surface area is
less than 20 m2/g, it is difficult to maintain a high
dispersion of the active hydrogenation component, and
the activity with respect to active hydrogenation
component is reduced. On the other hand, if the
specific surface area exceeds 300 m2/g, the porous
zirconia material has poor physical stability under
long-term reaction conditions, and it is difficult to
stably maintain the synergetic effects of the ruthenium
of the active hydrogenation component and the co-
catalyst zinc.
[0042]
The particle shape of the specific surface
area of the carrier is simple and the surface roughness
is small. When dispersed, a correlation between
particle diameter and specific surface area can be

obtained. In practice, however, they do not exactly
match because the primary particles contain holes and
cracks. These holes and cracks cause agglomeration and
condensation among the particles. For this reason, the
specific surface area of the carrier, which affects the
degree of dispersion of the supported active catalyst
component, is an important catalyst design indicator.
[0043]
The porous zirconia material preferably
possesses thermal stability. An index of the thermal
stability is such that the weight loss during calcining
at 250°C is preferably not more than 10% of that prior
to calcination. The porous zirconia material according
to the present invention preferably includes hafnium
oxide, and a preferable content thereof is from 0.2 to
5% by weight.
[0044]
The porous zirconia material used as the
carrier for the catalyst according to the present
invention preferably possesses crystallinity in the
same manner as commercially available products which
are commonly used as ceramic materials or catalyst
carriers. The effects of possessing crystallinity are
that, in terms of crystallographic structure, the
structure becomes stable and less susceptible to
volumetric shrinkage of the pores. For these reasons,
the supported active catalyst component can be stably
held in the pores. As a result, catalyst deterioration

under the reaction conditions is less likely to occur.
[0045]
In addition to monoclinic systems, tetragonal
systems, cubic systems and such similar systems exist
for zirconia crystal structures. Among these crystal
structures, however, a monoclinic system is preferable.
Because crystallization speeds up deterioration of the
specific surface area and mechanical strength of the
carrier, the degree of crystallization should not be
too high. A preferable crystallinity of the zirconia
should be one so that some crystals can be identified
with respect to crystalline orientation, but others
cannot be identified under observation at about 500,000
times magnification by transmission electron microscopy
(TEM), and crystal peaks of zirconia can be observed
under X-ray analysis.
[0046]
Synthesis of the porous zirconia material
according to the present invention can use a well-known
conventional method, such as sedimentation method, a
hydrolysis method or a hydrothermal method. For
example, synthesis can be carried out by thermal
processing of a zirconia sol obtained from hydrolysis
through heating. Alternatively, synthesis can be
carried out by neutralization by an alkaline chemical,
such as ammonia or the like, of an aqueous solution of
a water-soluble zirconium salt. Furthermore, a
commercially-available zirconia sol can be employed as

a raw material to yield a powder precursor by gelation
using an acid or an alkali, or to yield a powder by
subjecting to thermal processing.
Examples of the water-soluble zirconium salts
that can be used in the present invention include
zirconium chloride, zirconium acetate, zirconium
oxalate, potassium hexafluorozirconate (IV), sodium
hexafluorozirconate (IV), zirconium (IV) oxychloride,
zirconium (IV) oxynitrate, zirconium (IV) nitrate,
zirconium (IV) sulfate and the like.
[0047]
The size and shape of the zirconia particles
can be controlled by the formation conditions, such as
the solution concentration, PH, temperature and the
like at the time of synthesis. Generally speaking,
methods can be employed for controlling primary
particle diameter by using liquid-phase processing at a
temperature of 200°C or less for several hours to
several minutes. Methods can also be employed for
controlling secondary particle diameter under liquid-
phase or gas-phase at a temperature of 800°C or less.
However, a negative impact on catalytic performance may
result if the secondary particles are synthesized by
agglomeration of primary particles under acidic
conditions. Thus, it is preferable to synthesize the
secondary particles under neutral conditions or
alkaline conditions, or to subject the primary
particles to a thorough washing treatment prior to

agglomeration.
[0048]
The zirconia used as the carrier is
preferably of high purity, as the inclusion of organic
matter or minerals in the agglomerate of the carrier
particles leads to a decrease in catalytic performance.
Conventional processes which employ a template (for
example, JP-A-5-254827 and the process disclosed in
"Studies in Surface Science and Catalysis", 143, pp.
1035-1044 (2002)) are processes which construct
zeolite-type or wormhole-type pores in the carrier.
However, these processes have problems with the
constructed pore attributes and the removal of the
template. Thus, as these processes are not suitable,
as the carrier design required for the present catalyst
is difficult, and the pore design and interstitial-pore
type porous material formed from agglomeration of the
primary particles according to the present invention is
technologically different. A catalyst which uses as a
zirconia carrier obtained under a preparation process
employing a template does not always have sufficient
long-term stability under hydrothermal and acidic
conditions. Further, when such a preparation process
is used, a deterioration in catalytic performance, such
as cycloolefin selectivity or catalytic activity, can
be observed.
[0049]
A process which is generally used for a

supported catalyst preparation process can be used as
the process for supporting the active catalyst
component on the carrier. Since, in terms of achieving
high activity, it is important to thoroughly disperse
the catalyst component in the carrier, it is preferable
to use a process which fixes to the carrier walls. For
example, preferable processes include impregnating or
adsorbing the catalyst component into the carrier pores
or surfaces.
[0050]
Alternatively, processes such as an
evaporating-to-dryness process, a liquid-phase
adsorption process, a dipping process, a pore-filling
process, a spray process and the like, can be
preferably employed using a solution in which a
ruthenium compound is dissolved in a suitable solvent.
For a co-precipitation process or mixing process,
however, thorough dispersion of the catalyst component
and realization of high-performance catalytic
performance are difficult, even if limits are not
placed on the pore volume of the carrier, the surface
area, or the supported amount of active catalyst
component. When co-supporting zinc and ruthenium, they
may be supported separately or may be supported
simultaneously. The zinc and ruthenium supported on
the carrier are preferably located in proximity to each
other.
[0051]

Thus, the ruthenium-containing active
catalyst component which is dispersibly supported on
the carrier is subjected to reduction treatment in gas
phase or liquid phase. Conventional well-known
reducing agents, such as hydrogen, hydrazine, formalin,
sodium borohydride, formic acid and the like, can be
used as the reducing agent. Hydrogen or hydrazine can
be preferably used. Further, reduction may also be
carried out prior to charging the catalyst into the
reaction system, carried out after charging in the
reaction system, or carried out during the reaction.
The reduction temperature is usually between 50 and
450°C, and preferably from 80 to 250°C.
[0052]
It is thought that several factors contribute
to the solid catalyst of the present invention being
able to maintain long-term catalytic performance with
higher activity and higher selectivity than that of
conventional catalysts as a monocyclic aromatic
hydrocarbon partial hydrogenation catalyst. Such
factors include the carrier being stable, even under
hydrothermal and acidic reaction conditions; the active
hydrogenation component being uniformly and highly
dispersibly supported in the pores of the carrier; the
catalyst not being susceptible to catalyst degradation
from sintering, even under hydrothermal conditions, due
to the fact that the active catalyst component of the
pores is firmly adhered to the carrier; and less

susceptibility to poisoning effects than conventional
low support-ratio catalysts since the amount of
catalyst supported per 1 g of carrier can be increased.
[0053]
As the type of usage for the catalyst
according to the present invention, processes that
employ common solid catalysts may be used. Such
processes include a slurry-suspension process or a
fixed-bed flow process employing the catalyst as a
molded catalyst. In the present invention, water is
required to be present in the reaction system. While
the water content depends on the reaction form, usually
water of from 0.01 to 100 times the weight of the
monocyclic aromatic hydrocarbon can be used. It is
preferable, however, that the liquid phase which
comprises organic material, in which the raw materials
and the generated product are the main constituents
under the reaction condition, and water, forms a two-
liquid phase. In practice, water is preferably from
0.5 to 20 times the weight of the aromatic hydrocarbon.
[0054]
Further, in the present invention, a process
can be used wherein a metal compound other than the
catalyst component is present in the reaction system.
Examples of such a metal compound include metal
compounds of periodic law group 1 elements such as
lithium, sodium and potassium; group 2 elements such as
magnesium, calcium and strontium; rare-earth elements

such as lanthanum, cerium, samarium and terbium;
manganese, iron, nickel, cobalt, zinc, copper and the
like. The kinds of metal compounds which can be used
include carbonates, acetates, hydrochlorides, sulfates,
nitrates, oxides and hydroxides.
[0055]
The amount of these compounds present in the
reaction system can be appropriately selected depending
on the respective component characteristics and
reaction form. The metal compound may be used singly
or 2 or more kinds may be used simultaneously. The
presence of zinc salts, in particular, greatly improves
catalytic performance. As effective compounds thereof,
zinc sulfate, zinc hydroxide and zinc oxide are
preferable. Among these, zinc sulfate is most
preferable. If an aqueous zinc sulfate is used, the
concentration range is preferably within 0.1 to 30% by
weight as zinc sulfate in the aqueous solution. In
addition, basic zinc salts which are hardly soluble
zinc compounds can also coexist as the zinc compound in
the reaction system.
[0056]
"Hardly soluble zinc compounds" indicates
zinc salts which include a hydroxyl group or an oxygen
atom which are considered as a separate negative
constituent to the conjugate base residue of the
various acids; or zinc compounds which do not readily
dissolve in the reaction system. Examples include the

double salt of zinc sulfate and zinc hydroxide. It is
not necessary for these hardly-soluble zinc compounds
to completely dissolve in the reaction system. The
amount used when employing such a hardly-soluble zinc
compound should be no more than 3 times the weight of
the catalyst amount including the carrier. The metal
compound present in the reaction system may completely
exist as ions, exist as a compound, or in a state
wherein the two are mixed.
[0057]
In the present invention, the co-existing
water phases are preferably reacted while being kept
under neutral or acidic conditions. If a water phase
becomes alkaline, the reaction rate dramatically
decreases and, thus, is not preferable. A water phase
PH of from 0.5 to less than 7 is preferable, and more
preferable is from 2 to 6.5.
[0058]
The "monocyclic aromatic hydrocarbon" which
serves as a raw material to be used in the production
process of a cycloolefin according to the present
invention refers to benzene, toluene, xylene and lower-
alkyl benzenes. The conditions for the partial
hydrogenation reaction may be appropriately selected
depending on the type and amount of the catalyst and
additives to be used. The hydrogen pressure is from
0.1 to 20 MPa, and preferably from 1 to 10 Mpa. The
reaction temperature is in the range of from 50 to

250°C, and preferably from 100 to 200°C. The reaction
time can be appropriately selected by setting an actual
goal for the selectivity and yield of the desired
cycloolefin. Although there are no particular
restrictions, the reaction time is usually from several
seconds to several hours.
[0059]
The present invention will now be explained
in more detail by referring to examples; however, the
present invention is in no way to be restricted to
these examples. In addition, the evaluation methods of
the various physical properties will be described in
the following.
[0060]
(Carrier Particle Diameter Measurement)
Measurement of the carrier particle diameter
was carried out by observation using a Hitachi HD-2000
electron microscope and by using a Nikkiso Microtrac
UPA. Measurement of the average primary particle
diameter determined the length (Martin diameter) of
segments that divided the projected area of the
particles into two in a fixed direction, based on a
projected image observed using an electron microscope.
Specifically, the same number of each of 20 or more
large, medium and small points were observed from a
500,000 times or more magnified projected image,
wherein the number average diameter based on the
measured results of a total of not less than 60 points

was taken as the average primary particle diameter.
(Catalyst Particle Diameter Measurement)
Catalyst particle diameter measurement was
carried out in the same manner as that for the above-
described carrier particle diameter measurement.
[0061]
(Average Ruthenium Crystallite Diameter Measurement)
Average ruthenium crystallite diameter
measurement was measured using a Mac Science MPX18 X-
ray diffractometer. Specifically, the half-width of
the diffraction peak at a diffraction angle (29) 44° of
the ruthenium metal obtained from X-ray diffractometer
measurement was measured, for determination using the
Scherrer formula.
[0062]
(Other Measurements)
Pore diameter, specific surface area and pore
volume were measured using a Yuasa-Ionics Autosorb 3MP
apparatus and selecting nitrogen as the adsorption gas.
Specific surface area used desorption data obtained
from the BET method. Pore diameter and pore
distribution used desorption data obtained from the BJH
method, and pore volume employed the adsorption data
from P/PO at Max. The catalyst metal composition was
measured using Rigaku fluorescent X-ray analyzer.
Measurement of the elution component in the reaction
field was measured using a Rigaku JY-138-ICP emission
analyzer.

[0063]
(Catalyst Reaction Performance Evaluation)
Reaction evaluation was carried out using a
batch method employing an autoclave, wherein reaction
solution removed from time to time was analyzed using a
gas chromatograph (GC-14B manufactured by Shimadzu
Corporation) equipped with an FID detector. The below-
described benzene conversion ratio and cyclohexene
selectivity were calculated using the following
calculation formulae (1) and (2) based on the
experiment concentration analysis values.
[0064]
[Expression 1]

Further, "activity with respect to ruthenium"
expresses the benzene conversion rate (g/Hr) with
respect to Ru metal (g) contained in the catalyst,

which was calculated using the following calculation
formula (3) with a conversion ratio of 50% as a
reference.
[0066]
5 [Expression 3]
Activity with respect to Ru 1 g =
Used benzene amount (g) ._.
2 x Time (Hr) taken to reach conversion ratio of 5 0% x Used Ru amount (g)
[0067]
[Example 1]
(1) Porous zirconia material Synthesis
While stirring 500 g of a hafnium oxide-
10 containing zirconia sol (nitric acid stabilizer-
solution with a 10 wt% zirconia content; manufactured
by Newtecks Co., Ltd.) at 40°C, 25% ammonia water was
slowly charged thereto. This solution was stirred for
1 hour under heating at 80°C, and then subjected to
15 reduced-pressure drying at 90°C using an evaporator to
thereby form a solid. This mass of solidified powder
was ground, then, using 0.5 N sodium hydroxide, mixed
under stirring into an aqueous alkali solution for 1
hour at 60°C. The resulting solution was then
20 repeatedly washed with water and filtered. The
resulting filtrate was then dried at 110°C using a
vacuum dryer, which was then calcined at 250°C to yield
47 g of a white powder. Results of measurement of the

specific surface area and pore distribution of this
white powder using a nitrogen adsorption and desorption
method showed 1.5 wt% hafnium oxide-containing zirconia
which had a specific surface area of 229 m2/g. The pore
volume was 0.31 cm3/g and the average pore diameter was
3.5 ran. The pore volume of pore diameters 2.5 to 15 nm
was 85.1% by volume of the total pore volume of pore
diameters 2 to 150 nm. It was learned from observation
using an electron microscope and particle size
distribution measurement that the physical properties
of the powder were an average primary particle diameter
of 4.7 nm and an average secondary particle diameter of
2.3 µm.
[0068]
(2) Catalyst Preparation
An aqueous solution in which 8.9 g of zinc
nitrate was dissolved was charged with 20 g of the
hafnium oxide-containing zirconia porous material
obtained above, which solution was then subjected to
reduced-pressure drying at 80°C using an evaporator.
After calcining the resulting product for 2 hours at
350°C and supporting a zinc component thereon, the
product was subjected to, in order, alkali treatment,
washing and drying in the same manner as the porous
zirconia material. The resulting powder was charged in
an aqueous solution containing 22.24 g of aqueous
ruthenium chloride (9.99% by weight ruthenium content
solution) in distilled water, wherein after a

supporting operation of the ruthenium component was
carried out in the same manner as the zinc support
described above. The resulting product was then
reduced under a hydrogen atmosphere at 200°C, to thereby
yield a catalyst having a solid weight of 17 g.
Analysis of this catalyst using an X-ray diffractometer
showed an average crystallite diameter of the ruthenium
of 2.5 nm. The results of measurement of the ruthenium
and zinc content using a fluorescent X-ray analyzer are
shown in Table 1. Measurement of the catalyst
properties other than those described above was carried
out in the same manner as that for the physical
property measurement of the porous zirconia material,
wherein primary particles were 5.5 nm and secondary
particles were 2.3 µm. Average pore diameter was 3.5
nm and the pore volume of pore diameters 2.5 to 15 nm
was 8 6.7% by volume of the total pore volume. It was
also learned that the catalyst had a specific surface
area of 201 m2/g.
[0069]
(3) Benzene Partial Hydrogenation
A 1 liter autoclave was charged with 2 g of
the above-described solid catalyst and 280 ml of an
aqueous 10% by weight zinc sulfate solution, and purged
with hydrogen while stirring. The temperature was
raised to 150°C, and then hydrogen was further added
under pressure to give a total pressure of 5 MPa. The
resulting solution was left in this state for 22 hours

then subjected to reaction pre-processing of the
catalyst slurry. The autoclave pressure was
subsequently once lowered to 3 MPa, then 140 ml of
benzene were added under pressure along with hydrogen.
The resulting solution was reacted under high-speed
stirring at a total pressure of 5 MPa. Reaction
solution was removed from time to time to obtain
reaction selectivity and activity from the results of
analysis of the liquid-phase composition by gas
chromatography. Cyclohexene selectivity and the
activity with respect to ruthenium when the ratio of
benzene conversion was 50% are shown in Table 1. The
post-reaction catalyst was removed from the autoclave,
whereupon results of X-ray analysis showed that the
ruthenium average crystal diameter was 2.7 nm, which
was almost unchanged from that before reaction.
[0070]
[Example 2]
A hafnium oxide-containing porous zirconia
material was synthesized in the same manner as that of
(1) in Example 1, except that 45 g of white powder was
yielded by charging the above-describe zirconia sol
into a 1 liter autoclave, wherein the synthesis time
was extended to 10 hours at 120°C, and the calcining
conditions were changed to 400°C. Results of
measurement of the specific surface area and pore
diameter of this white powder using a nitrogen
adsorption and desorption method showed a specific

surface area of 109 m2/g, a pore volume of 0.34 cm3/g,
and an average pore diameter of 5.9 nm. The pore
volume of pore diameters 2.5 to 15 nm was 66.4% by
volume of the total pore volume of pore diameters 2 to
150 nm. It was learned from observation using an
electron microscope and particle size distribution
measurement for seeing the particle structure of this
powder that the physical properties of the powder were
an average primary particle diameter of 10.1 nm and an
average secondary particle diameter of 4.1 |µm. Next,
using this hafnium oxide-containing porous zirconia
material, a catalyst was prepared using the same
catalyst preparation process as that of (2) in Example
1. The primary particles of this catalyst were 9.5 nm
and the secondary particles were 3.9 µm. The average
pore diameter was 6.2 nm, and the pore volume of pore
diameters 2.5 to 15 nm was 61.7% by volume of the total
pore volume. It was also learned that the catalyst had
a specific surface area of 111 m2/g. Furthermore, using
this catalyst, after pre-processing of the catalyst in
the same manner as that in (3) of Example 1, a reaction
evaluation was performed. The ruthenium content and
zinc content of the prepared catalyst, and the reaction
results are shown in Table 1. The pre- and post-
reaction ruthenium average crystallite diameter were
2.6 nm, wherein no change was observed.
[0071]
[Example 3]

A 1 liter autoclave was charged with 4 g of
the solid catalyst prepared in Example 2 and 280 ml of
an aqueous 10% by weight zinc sulfate solution, and
purged with hydrogen while stirring. The temperature
was raised to 170°C, and then hydrogen was further added
under pressure to give a total pressure of 5 MPa. The
resulting solution was left in this state for 140 hours
then subjected to reaction pre-processing of the
catalyst slurry. The autoclave temperature was
subsequently lowered to 150°C and the pressure to 3 MPa,
then 140 ml of benzene were added under pressure along
with hydrogen. The resulting solution was reacted
under high-speed stirring at a total pressure of 5 MPa.
Reaction solution was removed from time to time to
obtain the analysis of the oil-phase composition by gas
chromatography. Cyclohexene selectivity and the
activity with respect to ruthenium were measured when
the ratio of benzene conversion was 50%. The reaction
results are shown in Table 1. The post-reaction
catalyst was removed from the autoclave, whereupon
results of X-ray diffraction showed that the ruthenium
average crystallite diameter was 2.8 nm, which was
almost unchanged from that before reaction.
[0072]
[Comparative Example 1]
(1) Porous Zirconia Material Synthesis
A mixed solution containing 140.1 g of 70%
zirconium tetrapropoxide (manufactured by Aldrich

Corp.), 150 ml of ethanol and 6 ml of acetyl acetone
was slowly dropped under stirring into a solution
containing 150 ml of distilled water, 150 ml of
ethanol and 32.7 g of cethyltrimethyl ammonium
bromide. The resulting solution was thoroughly mixed
under stirring at room temperature, and left to stand.
This resulting solution was transferred into an
autoclave, stirred at 120°C, then filtered and washed.
After drying, the resulting mixture was washed with
ethanol, and again dried to yield 28.8 g of a white
powder. Results of measurement of the specific
surface area and pore distribution of this white
powder using a nitrogen adsorption and desorption
method showed a specific surface area of 501 m2/g, a
pore volume of 0.93 cm3/g, and an average pore diameter
of 6.7 nm. The pore volume of pore diameters 2.5 to
15 nm was 38.1% by volume of the total pore volume of
pore diameters 2 to 150 nm. It was learned from
observation using an electron microscope and particle
size distribution measurement that the physical
properties of the powder were an average primary
particle diameter of 2.2 nm and an average secondary
particle diameter of 2.5 urn.
[0073]
(2) Catalyst Preparation and Benzene Partial
Hydrogenation
Using the above-described porous zirconia
material, a catalyst was prepared using the same
catalyst preparation process as that of (2) in Example

1. Using the catalyst, pre-processing of the catalyst
slurry was carried out in the same manner as that in
Example 3, and the reaction was evaluated.- In
contrast to the pre-reaction ruthenium average
crystallite diameter of 2.5 run, post-reaction
ruthenium average crystallite diameter was 5.5 nm,
whereby it was clear from these results that the
ruthenium average crystallite diameter had increased.
The ruthenium content and zinc content of the prepared
catalyst, and the reaction results are shown in Table
1.
[0074]
[Comparative Example 2]
Catalyst preparation was carried out in the
same manner as that of (2) in Example 1, except that
zirconia from Kojundo Chemical Laboratory Co.,Ltd.,
was made to serve as the carrier. Reaction evaluation
was performed using the same methods as those of
Example 3. The reaction results are shown in Table 1.
The physical properties of the used zirconia and
catalyst analysis were also measured in the same
manner

as that described above. The results were a zirconia
specific surface area of 13 m2/g, a pore volume of 0.19
cm3/g, and an average pore diameter of 56.5 nm. The
pore volume of pore diameters 2.5 to 15 nm was 3.4% by-
volume of the total pore volume of pore diameters 2 to
150 nm. It was learned from observation using an
electron microscope and particle size distribution
measurement that the physical properties of the powder
were an average primary particle diameter of 82.3 nm
and an average secondary particle diameter of 9.5 µm.
Results of measurement of the physical properties after
catalyst preparation showed an average primary particle
diameter of 59.5 nm and an average secondary particle
diameter of 6.6 µm of this catalyst. In addition, the
average pore diameter was 4 9.9 nm, wherein the pore
volume of pore diameters 2.5 to 15 nm was 5.8% by
volume of the total pore volume. Specific surface area
was 19 m2/g. Results of measurement of the post
catalysis ruthenium average crystallite diameter using
an X-ray diffractometer were 4.6 nm. The catalyst
after reaction was recovered. The ruthenium average
crystallite diameter was 6.5 nm. That is, it was
learned that the ruthenium was subjected to sintering
in the reaction field.
[0075]
[Comparative Example 3]
Catalyst preparation was carried out in the
same manner as that of (2) in Example 1, except that

zirconium hydroxide from Kojundo Chemical Laboratory
Co., Ltd., was made to serve as the carrier. The
catalyst was evaluated through reaction according to
the same procedure as those of Example 3. The reaction
results are shown in Table 1. In addition to
measurement of the specific surface area and pore
distribution of the zirconium hydroxide obtained in the
same manner as that described above, the post-catalysis
ruthenium and zinc were also measured for their
content. The results were a specific surface area of
313 m2/g, a pore volume of 0.36 cm3/g, and an average
pore diameter of 4.8 nm. The pore volume of pore
diameters 2.5 to 15 nm was 48.6% by volume of the total
pore volume of pore diameters 2 to 150 nm. From the
catalyst analysis results, the average crystallite
diameter of post-catalysis ruthenium was measured at
2.8 nm. The post-reaction catalyst was recovered,
wherein the results of measurement of the ruthenium
average crystallite diameter using an X-ray
diffractometer were 2.9 nm, which had hardly changed.
[0076]
[Comparative Example 4]
(1) Zirconia Surface-Modified Silica Porous Material
Synthesis
A 1 liter beaker was charged with 200 g of
distilled water, 160 g of ethanol and 20 g of
cethyltrimethyl ammonium bromide, which were made to
dissolve under stirring. The resulting solution was

slowly charged with 85 g of tetraethyl ortho-silicate,
thoroughly mixed under stirring, and left to stand at
room temperature. The resulting solution was filtered,
washed and then dried to obtain 22.1 g of a white
powder by calcining at 550°C. Results of measurement of
the physical properties of this white powder showed a
specific surface area of 830 m2/g and a pore volume of
1.78 cm3/g. Subsequently, 20 g of the above-described
white powder was soaked in an aqueous solution in which
18 g of zirconium oxychloride octahydrate was
dissolved. This solution was subjected to reduced-
pressure drying using an evaporator and calcined at
600°C to thereby synthesize a zirconia surface-modified
silica porous material. Results of measurement of the
specific surface area and pore distribution of the
powder which had adsorbed this zirconia were a specific
surface area of 510 m2/g, a pore volume of 0.51 cm3/g
and an average pore diameter of 3.7 nm. The pore
volume of pore diameters 2.5 to 15 nm was 4 9.1% by
volume of the total pore volume of pore diameters 2 to
150 nm. It was learned from observation using an
electron microscope and particle size distribution
measurement that the physical properties of the powder
were an average primary particle diameter of 2.1 nm and
an average secondary particle diameter of 8.4 p.m.
[0077]
(2) Catalyst Preparation and Benzene Partial
Hydrogenation

Using the above-described zirconia surface-
modified silica porous material, a catalyst was
prepared using the same catalyst preparation process as
that of (2) in Example 1, and this catalyst was used
for reaction evaluation using the same method as that
of Example 3. The pre-reaction physical properties of
the catalyst were an average primary particle diameter
of 4.3 nm and an average secondary particle diameter of
8.9 µm The average pore diameter was 4.8 nm, and the
pore volume of pore diameters 2.5 to 15 nm was 64.2% by
volume of the total pore volume. Specific surface area
was 251 m2/g, while the average crystallite diameter of
the ruthenium could not be measured from the X-ray
diffraction image since it was 2 nm or less. The
average crystallite diameter of the post-reaction
ruthenium was 3.3 nm, whereby ruthenium crystal growth
was observed. The ruthenium content and zinc content
of the prepared catalyst, and the reaction results, are
shown in Table 1.



[0079]
[Example 4]
A 200 ml polybeaker was charged with 5 g of
the hafnium oxide-containing zirconia material
synthesized in (2) of Example 1 and 100 g of an aqueous
10% by weight zinc sulfate solution, and stirred for 3
hours at 60°C. The stirred solution was then filtered
using a 0.2 µm membrane filter, and the resulting
filtrate was sampled to determine the zirconium elution
amount contained in the filtrate. The results showed
that the amount of zirconium in the aqueous solution
was at the analytical method detection limits of 2 ppm
or less. For comparison, 5 g of the zirconia surface-
modified silica material synthesized in (1) of
Comparative Example 4 were processed in the same manner
to determine the silicon elution amount contained in
that filtrate. Those results showed that the amount of
silicon in the aqueous solution was 330 PPM.
[0080]
[Example 5]
An aqueous solution of 14.8 g of lanthanum
acetate hydrate dissolved in distilled water was
charged with 20 g of the hafnium oxide-containing
porous zirconia material used in Example 2. The
resulting solution was dried under reduced pressure at
80°C, and then the dried residue was subjected to
calcination for 5 hours at 400°C. The calcined solid
contained 25% by weight of lanthanum in terms of the

oxide. Subsequently, this was charged in an aqueous
solution in which 22.24 g of an aqueous solution of
ruthenium chloride (ruthenium 9.99% by weight content)
was dissolved in distilled water. The ruthenium
component was loaded by adsorption, and then washed at
room temperature. The resulting product was then
subjected to, in order, alkali treatment for 1 hour at
60°C, washing at room temperature, filtering and drying
under reduced pressure at 110°C. After drying, the
catalyst was not subjected to a reduction operation.
The average primary particle diameter of this catalyst,
which had not undergone a reduction operation, was 8.3
nm and the average secondary particle diameter was 3.3
µm. The average pore diameter was 5.1 nm, and the pore
volume of pore diameters 2.5 to 15 nm was 60.5% by
volume of the total pore volume. Specific surface area
was 119 m2/g. Using this catalyst, after pre-processing
of the catalyst using the same process as that of (3)
of Example 1, the reaction was evaluated under the same
conditions. The reaction results and the ruthenium
content of the catalyst are shown in Table 2. The
post-reaction catalyst was removed, and results of
measuring the X-ray diffraction showed an average
crystallite diameter of the ruthenium of 2.7 nm.
Further, the average primary particle diameter of the
recovered catalyst was 8.5 nm and the average secondary
particle diameter of the same was 3.3 µm.
[0081]

[Comparative Example 5]
A 10 L stainless steel vessel was charged
with 5 kg of a zirconia sol (alkali stabilizer-
containing solution with a 10 wt% zirconia content;
manufactured by Newtecks Co., Ltd.), and then charged
with a 5 wt.% aqueous solution of lanthanum acetate
under stirring. After this solution was thoroughly
stirred at room temperature, a spray dryer was used for
spray drying, then the resulting powder was calcined to
obtain 410 g of a white powder which supported 20% by
weight of lanthanum by oxide conversion. This powder
had a specific surface area of 64 m2/g, a pore volume of
0.32 cm3/g and an average pore diameter of 22.7 nm. The
pore volume of pore diameters 2.5 to 15 nm was 18.6% by
volume of the total pore volume of pore diameters 2 to
150 nm. It was learned from observation using an
electron microscope and particle size distribution
measurement that the average primary particle diameter
was 17.8 nm, and an average secondary particle diameter
for this powder was 53 µm. Using this powder,
adsorption and support of the ruthenium was carried out
in the same manner as Example 5. The average primary
particle diameter of the catalyst was 4.3 nm and the
average secondary particle diameter of the same was 53
µm. The average pore diameter was 31.5 nm, and the
pore volume of pore diameters 2.5 to 15 nm was 20.1% by
volume of the total pore volume. Specific surface area
was 64 m2/g. This catalyst was subjected to catalyst

pre-processing using the same method used in (3) of
Example 1 for reaction evaluation under the same
conditions. The results are shown in Table 2.
[0082]
[Example 6]
A 1 liter Hastelloy autoclave was charged
with 4 g of the solid catalyst prepared in Example 5
and 280 ml of an aqueous 10% by weight zinc sulfate
solution, and purged with hydrogen under stirring.
After the temperature was raised to 170°C, hydrogen was
further added under pressure to give a total pressure
of 5 MPa. The resulting solution was left in this
state for 140 hours then subjected to reaction pre-
processing of the catalyst slurry. The autoclave
temperature was subsequently lowered to 150°C and the
pressure to 3 MPa, then 140 ml of benzene were added
under pressure along with hydrogen, and the resulting
solution was reacted under high-speed stirring at a
total pressure of 5 MPa. Reaction solution was removed
from time to time for analysis of the oil-phase
composition by gas chromatography. Cyclohexene
selectivity and the activity with respect to ruthenium
when the ratio of benzene conversion was 50% were
measured. The reaction results are shown in Table 2.
Further, the post-reaction catalyst was removed from
the autoclave, whereupon the results of measuring X-ray
analysis showed that the ruthenium average crystallite
diameter was 2.9 nm.



[INDUSTRIAL APPLICABILITY]
[0084]
The present invention is useful as a catalyst
for production of a cycloolefin which possesses high
activity and high selectivity and in which catalyst
life and handleability are improved.

WE CLAIM:
1. A catalyst for production of a cycloolefin by partial hydrogenation of a
monocyclic aromatic hydrocarbon, wherein the catalyst comprises zirconia as
a carrier and ruthenium as an active catalyst component, wherein said
catalyst is constituted from particles having an average primary particle
diameter of said catalyst in a range of from 3 to 50 nm and an average
secondary particle diameter in a range of from 0.1 to 30 µm.
2. The catalyst as claimed in claim 1, wherein the catalyst has an
average pore diameter in a range of from 2.5 to 15 nm, and a pore volume
in the 2.5 to 15 nm range of the pore diameter is 50% by volume or more of
the total pore volume having pore diameters from 2 to 150 nm.
3. The catalyst as claimed in claim 1, wherein the average crystallite
diameter of the ruthenium is from 2 to 15 nm.
4. The catalyst as claimed in claim 1 or 3, wherein the catalyst comprises
zinc or a zinc compound.
5. The catalyst as claimed in claims 1 to 4, wherein the catalyst has a
specific surface area of from 20 to 300 m2/g-
6. The catalyst as claimed in claims 1 to 5, wherein the carrier is an
interstitial-pore type porous zirconia material formed by assemblage of the
primary particles.
7. The catalyst as Claimed in claim 6, wherein the carrier is a hafnium
oxide-containing zirconia.

8. A production process of a cycloolefin by partial hydrogenation of a
monocyclic aromatic hydrocarbon, comprising partially hydrogenating the
hydrocarbon in liquid phase in the presence of water, by using the catalyst
as claimed in any of claims 1 to 7.
9. The production process as claimed in claim 8, wherein a zinc
compound or a zinc ion, or both, are present in the liquid phase.


A catalyst for production of a cycloolefin by partial hydrogenation of a
monocyclic aromatic hydrocarbon, wherein the catalyst comprises zirconia as
a carrier, and particles having an average primary particle diameter in a
range of from 3 to 50 nm and an average secondary particle diameter in a
range of from 0.1 to 30 µm.

Documents:

00023-kolnp-2007 correspondence-1.1.pdf

00023-kolnp-2007 priority document-1.1.pdf

00023-kolnp-2007-correspondence-1.3.pdf

00023-kolnp-2007-correspondence-1.4.pdf

00023-kolnp-2007-correspondence-1.5.pdf

00023-kolnp-2007-form-18.pdf

00023-kolnp-2007-others document.pdf

00023-kolnp-2007-others-1.1.pdf

0023-kolnp-2007 abstract.pdf

0023-kolnp-2007 assignment.pdf

0023-kolnp-2007 claims.pdf

0023-kolnp-2007 correspondence others.pdf

0023-kolnp-2007 description (complete).pdf

0023-kolnp-2007 form-1.pdf

0023-kolnp-2007 form-2.pdf

0023-kolnp-2007 form-3.pdf

0023-kolnp-2007 form-5.pdf

0023-kolnp-2007 international publication.pdf

0023-kolnp-2007 international serch authority report.pdf

0023-kolnp-2007 pct form.pdf

0023-kolnp-2007 priority document.pdf

0023-kolnp-2007-correspondence-1.2.pdf

0023-kolnp-2007-others.pdf

23-KOLNP-2007-ABSTRACT 1.1.pdf

23-KOLNP-2007-ABSTRACT 1.2.pdf

23-KOLNP-2007-ABSTRACT.pdf

23-KOLNP-2007-AMANDED CLAIMS 1.1.pdf

23-KOLNP-2007-AMANDED CLAIMS.pdf

23-KOLNP-2007-CANCELLED PAGES.pdf

23-KOLNP-2007-CORRESPONDENCE 1.1.pdf

23-KOLNP-2007-CORRESPONDENCE-1.2.pdf

23-KOLNP-2007-DESCRIPTION (COMPLETE) 1.1.pdf

23-KOLNP-2007-DESCRIPTION (COMPLETE) 1.2.pdf

23-KOLNP-2007-EXAMINATION REPORT.pdf

23-KOLNP-2007-FORM 1-1.2.pdf

23-KOLNP-2007-FORM 1.1.pdf

23-KOLNP-2007-FORM 13-1.1.pdf

23-KOLNP-2007-FORM 13-1.2.pdf

23-KOLNP-2007-FORM 18.pdf

23-KOLNP-2007-FORM 2-1.2.pdf

23-KOLNP-2007-FORM 2.1.pdf

23-KOLNP-2007-FORM 3.1.pdf

23-KOLNP-2007-FORM 5.pdf

23-KOLNP-2007-GRANTED-ABSTRACT.pdf

23-KOLNP-2007-GRANTED-CLAIMS.pdf

23-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

23-KOLNP-2007-GRANTED-FORM 1.pdf

23-KOLNP-2007-GRANTED-FORM 2.pdf

23-KOLNP-2007-GRANTED-SPECIFICATION.pdf

23-KOLNP-2007-OTHERS 1.1.pdf

23-KOLNP-2007-OTHERS 1.2.pdf

23-KOLNP-2007-OTHERS-1.3.pdf

23-KOLNP-2007-PA.pdf

23-KOLNP-2007-REPLY TO EXAMINATION REPORT 1.1.pdf

23-KOLNP-2007-REPLY TO EXAMINATION REPORT-1.2.pdf

23-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf

23-KOLNP-2007_2-PETITION UNDER RULE 137.pdf


Patent Number 251528
Indian Patent Application Number 23/KOLNP/2007
PG Journal Number 12/2012
Publication Date 23-Mar-2012
Grant Date 21-Mar-2012
Date of Filing 03-Jan-2007
Name of Patentee ASAHI KASEI CHEMICALS CORPORATION
Applicant Address 1-2, YURAKUCHO 1-CHOME, CHIYODA-KU, TOKYO
Inventors:
# Inventor's Name Inventor's Address
1 AKIYOSHI FUKUZAWA C/O ASAHI KASEI KABUSHIKI KAISHA, 1-2, YURAKUCHO 1-CHOME, CHIYODA-KU, TOKYO
PCT International Classification Number B01J23/60, B01J21/06, B01J23/63
PCT International Application Number PCT/JP2005/005844
PCT International Filing date 2005-03-29
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2004-202887 2004-07-09 Japan