Note: Descriptions are shown in the official language in which they were submitted.
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The C~nadian pa~e~t No. 11005,777 relates to a process for the
catalytic conversion of a residual hydrocarbon oil, in which process the
oil is first demetallized and subsequently catalytically converted. Accord-
ing to the said patent the demetallization is carried out by contacting the ~-oil at elevated temperature and pressure and in the presence of hydrogen
with a catalyst comprising one or more metals having hydrogenation activity
on a carrier, which catalyst meets a number of requirements with regard to
par~icle diameter and porosity. In the said patent it is stated tha~ for
the preparation of the catalysts the well-known nodulizing technique can be
used. According to this technique catalyst particles or catalyst carrier
particles having a diameter of at most 0.1 mm are agglomera~ed with the aid
of a granulation liquid ~o particles having a diameter of at least 1.0 mm.
Continued investiKation of the demetallization of residual hydro-
carbon oils using catalysts that meet the requirements o the said patent
with regard to particle diameter and porosity showed that the activity of
such catalysts prepared according to the nodulizing technique greatly depends
on their pore volume that consists of pores with a diameter larger than 50
nm. It has been found that these catalysts have an optimum activity when
the said pore volume is at least 0.2 ml/g.
The present invention therefore relates to a process for the cata-
lytic conversion of a residual hydrocarbon oil, in which process the oll is
first demetallized and subsequently catalytically converted and in which
demetallization is carricd out by contacting the oil at elevated temporature
and pressure and in the presence o hydrogen with a catalyst comprising one
or more metals having hydrogenation activity on a carrier, which catalyst
has been prepared according to the noduli2ing technique and which meets the
ollowing requirements:
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( 1 ? ~/d ~3,5-0.02 v, in wh;ch ~ i~ the speci~ic average ~ore diameter
in nm, d is the ~pecific average particle diameter in mm and
v is the percentage of the total pore volume tha* onsists of
pores with ~ didmeter larger than 100 nm,
(2) the total pore volume i6 lareer than 0.40 ml/K,
(3) v is smaller than 50,
(4) the pore volume consisting of pores with a diameter larger
than 50 nm i5 at least 0.2 ml/g, and
(5) ~he specific surface area is larger than 100 m2/g; for the case
that the catalyst has such a p and d that the quotient p/d is
larger than 3.5-0.02 v. but at most 10-0.15 v, the catalyst has
to meet the following additional requirements:
(a) the nitroeen pore volume is larger than o.60 m /g
~b) the specific surface area is larger than 150 m /~, and
(c) p is larger than 5 nm.
In the process according to the invention preference i8 given
to a catalyst whose pore volume consisting of pores with a diameter
larger than 50 nm i5 at least 0.3 mljg.
As mentioned hereinbefore, in the ca~alyst preparation according
to the nodulizing technique catalyst particles or catalyst-carrier
particles having a diameter of at most 0.1 mm are agglomerated with
the aid of a granulation liquid to particles having a diameter of
at least 1.0 mm. In actual practice cataly~t preparation according
to the nodulizinK technique usually takes place as follows. Cataly~t-car-
rier material having a diameter of at most 0,1 mm ia placed on a rotntin~
disc provided with a raised edge and a scraping device. ~he disc i9
disposed at a specific angle to the horizontal plane. A granulation
liquid is sprayed onto the carri¢r material that is in continuous
motion on the disc. In practice, when aIumina is used as a carrier,
3 a dilute aqueous solution of acetic acid or citric acid i8 usually
' emplcyed as the granulation liquid. During the residence of the small
particles on the disc larger particles are formed from the small ones
by agglomeration. The noduli~ing technique can be carried out both
batchwise and continuously. When the continuous process i5 used finely
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di~persed material i~ continuously supplied to ~he rotating ~isc and
agglomerated material continuously leaves the disc via the top of
the raised edge when this i9 in it8 lowest position. A~ter the sgglomerated
particles have left the di~c a ~ieve fraction with the desired diameter
is separated from it. Particles with a diameter ~maller than that
of the desired sieve fraction may be recycled to the disc. I~ the
agglomerated material contain~ particles with a diameter larger than
that of the de~ired sieve ~raction, these particles, a~ter reduction
of the particle size, for instance by grinding, ~ay also be recycled
to the disc. The conversion of the agglomerated material with the
desired particle si~e into a suitable carrier material takes place
by drying and calcination. The emplacement of one or more metals ~ith
hydrogenation activity on the carrier material thus prepared, is usually
e~ected by impregnation with an aqueous solution of compounds of
the re~pective metals, ~ollowed by drying and calcination o~ the impregnated
material.
In the process according to the invention use is preferably made
of cat~ly~ts comprising 0.1-15 pbw o~ one or more metals having hydrogenation
activity per 100 pbw carrier. The metal~ having hydrogenation activity
are pre~erably selected ~rom the group consisting of nickel, cobalt,
molybdenum and v~nadium. It i~ further preferred that the catalysts
~ho~ld comprise at lea~t one metal selected from the group consisting
o~ nickel and cobalt and at lea~t one metal selected ~rom the ~roup
consi~ting o~ molybdenum and vanadium and fur~her that the ~tomic
ratio between nickel and/or cobalt on the one hand and molybdenum
and/or vanadium on the other hand i8 between 0.05 and 3Ø Suitable
metal combinations are nickel-vanadium, cobalt-molybdenum and nickel-molybdenum.
The quantity o~ metals having hydrogenation activity present in the
catalysts pre~erably amounts to 0.5-10 pbw and in particular 2.0-7.5
pbw per 100 pbw carrier. Especially preferred demetallization catalysts
according to the invention are catalysts comprising about 0.5 pbw
nickel and about 2 pbw vanadium per 100 pbw carrier, as well as catalysts
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comprising abou-t 1 pbw nickel or cobalt and about 4 pbw molybdenum
per 100 pbw carrier. The metals may be present on the carrier in the
metallic form or in the form of their oxides or sulphides. Preference
is given to catalysts in which the metals are present on the carrier
in the form of their sulphides. Sulphidation of the present catalysts
may be carried out by any technique for the sulphidation Or catalysts
known in the art.
Suitable carriers for the present catalysts are oxides of the
elements of Group II, III or IV of the Periodic ~able of elements
or mixtures of the said oxides, such as silica, alumina, magnesia,
zirconia, silica-alumina and silica-magnesia. If for the preparation
of the present catalysts use is made of any of the above-mentioned
oxidic carriers, preference is given to the application of alumina
or silica for this purpose. Another type of material that is very
suitable to serve as a carrier for the present catalyst3 is soot,
in particular a soot obtained as by-product of the partial oxidation
of hydrocarbons with air, ox~gen or mixtures of air and oxygen, either
in the presence or in the ab~ence of steam. In addition to the suitability
of soot as a carrier for the present demetallization catalysts, the
use of soot for this purpose carries with it an additional advantage
that is not achieved if any of the oxidic carriers mentioned hereinbefore
is a~plied. This can be elucidated as follows. Although the cataly~ts .
according to the invention show a long life in the demetallization
of residual hydrocarb~n oils, even these catalysts will in the lone
run be deactivated as result Or the deposition of large amounts Or
metals9 in particular vanadium and nickel~ and therefore, after a
certain time of operation~ they have to be replaced. If it is intended
~¦ to recover the deposited metals from the deactivated catalyst, the
use Or a catalyst on soot as the carrier offers the considerable advantage
over catalysts on other carrier materials that the carrier can simply
be removed from the deactivated catalyst by combustion, after which
a mixture of the metals concerned is left behind in the form Or their
oxides for further working up.
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During the investigation o~ the preparation of demetallization
catalysts according to the nodulizing technique five modifications
of the usual procedure were found by the Applicant, which modifications
will each produce a favoura~le e~fect. These modifications will be
described in more detail hereinafter.
l. In the preparation of catalysts on the basis of alumina as a
carrier an aqueous solution Or acetic acid or citric acid is
usually applied as the granulation liquid. It has been found
that when dilute nitric acid is applied as the granulation liquid,
alumina-based catalysts can be obtained with a crushing strength
and density that are considerably higher than when an aqueous
solution of citric acid or acetic acid is applied.
2. When in the preparation of the catalysts the starting material
is mixed with B certain amount of glass powder and, in addition,
the particles formed by the nodulizing technique are subjected
to a calcination at a temperature above the so~tening temperature
Or glass, catalysts can be obtained with a considerably increased
crushing strength. The amount of glass powder applied is preferably
0.5-15 %w based on the amount Or starting material with which
it is mixed.
3, When phosphorus i9 incorporated into the catalysts their acti~ity
in the demetallization o~ residual hydrocarbon oils is considerably
increased. The incorporation of phosphorus into the catalysts
can take place durin¢ any sta~e in the cataly~t preparation.
The incorporation of phosphoru~ can, for instance, very ~uitably
take place by addition of a phosphorus compound to the granulation
liquid ~nd/or to the impregnation liquid that is applied for
the emplacement of the me~als with hydrogenation activity on
the particles formed. The amount of nhosphorus compound is preferably
chosen in such a way that a catalvst is obtained comprising 0.5-5
%w phosphorus per 100 pbw carrier.
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4. In the cataly~t preparation according to the nodulizing technique
larger particles, which are more or less ~pherical, are formed
from the starting material, The size of the particles formed
i8 determined, among other ~aGtors, by the residence time of
the material on the rotatine disc, After the particles have attained
approximately the desired Bi ze they are removed ~rom the disc
and are dried and calcined. It has been ~ound that cataly6ts
with a considerably higher density can be prepared, ~hen the
pa`rticles ~ormed3 aMer they have left the rotating disc but
beYore dr~ing and calcination, are rotated ~o~ some time, for
instance in a rotating drum. Such rotation of the particles ~ormed
preferably take~ place during a period of time at least equal
to the residence time of the material on the rotating disc.
5. In the catalyst preparation according to the nodulizing technique
the usual procedure ig ~or the carrier particles, after they
O have beep ~ormed on the disc, to be dried and calcined, rollowed
by emplacement o~ the de~ired metals with hydrogenation activit~
on the calcined materîal, for instance by impregnation with ~n
aqueous ~olution containing salts of the relevant metals. Finally,
the impregnated material is dried and calcined, It has been ~ound
that this catalyst preparation can be considerably simpli~ied
by incorporating the metal salts into the granulation liquid.
When the emplacement o~ thè metals in the catalyst i~ carried
out in thi~ way the separate impregnation ~tep as well as the
~econd drying and cQlcination steps can be omitted, which in
the large-scale preparation of the present catalyst~ obviously
a~ords a considerable saving.
Ex~mples of suitQble wster-soluble metal co~pounds which m~y
be applied in the preparation of the present c~talysts are nitrates,
chlorides, formates and acetates of nickel and cobalt, ammonium molybdate,
vanndyl oxalate, vanadyl sulphate and vanadyl acetyl acetonate and
ammoni~m vanadate~
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For the catalytic hydrodemetallization of residual hydrocarbon
oils according to the invention use is preferably made of catalyst particles
having a d of 1,0~4.0 mm and in particular of 1.5-3.5 mm.
If in the preparation according to the invention a catalyst is
applied with such a p and d that the quotient p/d is larger than 10-0.15 v,
it is preferred to choose a catalyst having a total pore volume of at least
0.50 ml/g and a specific surface area above 150 m2/g.
The invention will now be further elucida~ed with the aid of the
following example~ which refers to the demetallization s~ep of the process.
Example
A residual hydrocarbon oil having a total vanadium and nickel con-
tent of 62 ppmw~ a C5-asphaltenes content of 6.4 %w and a sulphur content
of 3~9 %w, which oil had been obtained as a residue in the atmospheric dis-
tillation of a Middle ~ast crude oil (oil B accord.ing to Canadian patent No.
1,005,777),was catalytically hydrodemetallized at different space velocities
and using 5 differ~nt catalysts. To this end the oil together with hydrogen
was passed downwards through a cylindrical vertically disposed fixed catalyst
bed at a temperature of 420C, a total pressure of 150 bar and an exit gas
rate of 250 Nl H2/kg of fresh eed. The catalysts were applied in the orm
of their sulphides.
The preparation of the 5 catalysts which were applied in the de-
metallization experiments as well as the preparation of 3 other catalysts
according to the invention, which had been prepared via the nodulizing tech-
nique, are mentioned hereinafter. The results of the demetallization experi-
ments together with the space velocities applied and the properties of the
catalysts have been collected in the table.
Catalyst A
As starting material use was made of an alumina obtained by
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~pr~y-drying with a d smaller than 0.09 mm, this alumina having a
pore volume of 1.2 ml/g consisting of pores with a diameter larger
than 50 nm. 0~ thi~ alumina 100 ~ was put on a rotatin~ disc and 100
ml o~ an aqueous solukion containing 3.5 e citric acid was ~radually
sprayed onto it. The rotating disc, which was provided with a raised
edge Or 10 cm high, had a diameter of 40 cm. The disc made 40 re~olutions
per minute and was disposed at an angle of 45 to the hori~ontal plane.
After 15 minutes' residence time the nodules formed were removed from
the disc. After dryin~ at 120C a sieve fraction with a d of 2 0 mm
was isola~ed from the dried material. After 1 hour's calcination at
600C the particles were impregnated with an aqueous solution comprising
nickel nitrate and a~monium molybdate. Finally, the impregnated material
was dried at 120C and calcined for 1 hour at 500C. '~he catalyst
thus prepared comprised 1 pbw nickel and 4 pbw molybdenum per 100
pbw alumina.
C&talyst B
This catalyst was prepared in substantially the same way as catalyst
A, the di~ference being however, that in the present case 100 ml of
an aqueous solution comprising 3.5 g nitric acid was used as the granulation
liquid.
Catalyst C
This catalyst wa~ prepared in substantially the same way as catalyst
A, the di~erence being, however, that in the present case 2 g glass
powder with a d smaller than 0.09 mm was added to the alumina starting
mater;al and that after calcination at 600C another calcination was
carried out for 1 hour at 800C.
CatalyGt D
This catalyst was prepared in substantially the same way as
catalyst C, the difference being, however, that in the present case
so much NH4H2P04 was added to the impregnation liquid comprising nickel
and molybdenum that a catalyst was obtained comprising in addition
to 1 pbw nickel and 4 pbw molybdenum, 1 pbw phosphorus per lO0 pbw alumina.
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Catalyst E
This catalyst wa~ prepared in substantially the same way BS catalyst C, the
dif'f'erence beîng, however, that in the present case the nodules, after
having left the disc, were rotated for another hour in a rotating
drum. ~ ~
Cataly~t F ~ _
This catalyst was prepared in ~ubstantially the same way as catalyst
A, the difference being, however~ that in the present case the starting
~aterial WA8 an alumina obtained by spray-dryin~ having a pore volume
of 0.36 ml/g consi3ting of pores with a diameter larger than 50 ~m.
Catalyst G
The starting material was a soot with a d smaller than 0.1 mm~
which ~oot had a pore volume of` o.58 ml/g consistin~ of pores with
a diQmeter larger than 50 nm, The soot had been obtained as a by-product
Or the partial oxidation of' hydrocarbons with air. The soot being
available in the form of' a slurry in water, was isolated from it by
filtering, drying o~ the filter cake and grinding Or the dried material
to the particle si~e mentioned The nodules were prepared f'rom the
soot in sub~tantialLy the same way as the noaules f'rom alumina as
described for catalyst A, the difference bei~g, however, that in the
present case an a~ueous ~olution of ligno sulphonate was used as the
granulation liguid. A~ter 15 minutes~ residence time the nodules were
removed from the di~c. After drying at 120C n ~ieve fraction with
a d of 1,8 mm wQs icolated from the dricd material. A~ter 1 hour~
calcination in a nitrogen~3tream at 700C these particles were impregnated
with an aqueous solution comprisin~ nickel nitrate and vanadyl oxalate.
FinQlly, the impregnated material was dried at 120C and calcined
for 1 hour at 500 C in a nitrogen stream. The catalrst thus prepared
comprised 0 5 pbw nickel and 2 pbw vanadium per 100 pbw soot.
Catalyst H
This catalyst was prepared in substantially the same way as catalyst
G, the difference beine, however, that in the present case the starting
material was a soot obtained as a by-product of the partial oxidation
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of hydrocarbons wi~h air and having a pore volume of 0.26 ml/g consisting
of pores with a dia~eter larger than 50 nm and that the nodul~s formed9 after
having left the disc, were rotated for another hour in a rotating drum.
Table
Catalyst No. A B C D E F G H
Specific surface area,
m2/g 312 270 248 264 239 230 450 49S
Total pore volume~
ml/g 1.28 1.18 1.41 1.391.10 0.85 1.50 1.24
~itrogen pore volume,
mlJg 0.73 0.69 0.69 0.740.65 0.70 0.80 0.88
Pore volume consisting
of pores with a dia-
meter larger than
50 nm, ml/g 0.59 0.63 0.75 0.800.55 0.10 0.36 0.14
v, % 36 41 44 47 38 7 8 6 ,
d, mm 2.0 2.3 2.4 2.9 2.5 1.5 1.8 1.25
p, nm 38 62 67 90 60 7.8 38 27
Crushing2strength,
kg/cm 8.0 9.5 9.4 9.1 9.3 7.8 6.5 7.2
Density, g/cm3 0.29 0.36 0,31 0.300.39 0.35 0.31 0.35
Experirnent No. 1 2 3 4 5
Space velocity,
l.l-l~h-l 4.6 4.6 3.0 3.1 3.1
V~Ni removal (%w)
after processing
5 tons feed/kg
catalyst 50 55 41 51 42
All the catalysts mentioned in the table ara catnlysts that can be
applied according to Canadian patent No. 1,005,777. Catalysts A-E, G and H
with p/d ~10.0-0.15 v also meet the other requirements of the said Canadian
patent with respect to v~50%), total pore volume ~0.40 ml/g) and specific
surface area ~ 100 m2/g). Catalyst F with 10.0-0.15 v ~p/d~3.5-0.02 v
also meets ~he other requirements of the said Canadian patent with respect
to v(c 50~), p(~5nm), nitrogen pore volume t~0.60 ml/g) and specific sur-
face area (~7150 m2/g).
Of the catalysts mentioned in the table, catalysts A-E and G, which
have been prepared according to the noduLizing technique and the pore volume
of which consisting of pores with a diameter larger than 50 nm is at least
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0,2 ml/g, are catalysts that can be ayplied according to the present patent
application. Catalys~s P and H, although prepared according to the noduliz-
ing ~chnique, bu~ whose pore volume consisting of po~es with a diameter ~-
larger than 50 nm is less than 0.2 ml/g, fall outside the scope of the pre-
sent patent application. They have been included in the table for comparison.
Comparison of the crushing strengths and the densities of catalysts
A and B shows the favourable effect of the use of dilute nitric acid as the
granulation liquid instead of an aqueous citric acid solution.
The favourable effect of the incorporation of glass powder in the
starting material in combination with calcination at a temperature above the
softening temperature of glass is found when comparin~ khe crushing strengths
of catalysts A and C.
Comparison of the densities of catalysts C and E shows the favour-
able effect of post-rotation of the nodules after these have attained the
desired size on the rotating disc.
According to Canadian patent No. 1,005,777 a catalyst, under the
conditions applied in the present demetallization experiments, mùst meet the
criterion that the catalyst is still capable of removing more than 40 %w of
the total amount of vanadium and nickel present in oil B after S tons of this
oil have been processed over the catalyst at a space velocity of at least 2.9
1.1 l.h 1.
All the experiments shown in the table ~in which the catalysts
met the above requirements concerning ~w Ni+V removal) are demetallization
axperiments within the scope o~ Canadian patènt No. 1,005,777. Of the experi~
ments shown iTI the table, experiments 1,2 and 4 (in which catalysts C, D and ?
G were applied, respectively) are demetalli~ation experiments according to
the present invention. Experiments 3 and 5 (in which catalysts F and H were
applied, respectively) all outside the scope of the present invention. They
have been included for comparison.
The influence of the catalysts' pore volume consisting of pores
with a diameter larger than 50 nm on their demetallization activity is found
when comparing the results of experiments 1 and 2 with those of experiment
3 and comparing the results of experiment 4 with those
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of experiment 5. It has been found that catalysts C and D (in which
the sQid pore volume i8 more than 0.20 ml/g) are still capable of
removing 50 and 55 ~w V+Ni, respectively, aM er processing 5 tons
feed/kg catalyst at a space velocity of 4.6 l.l .h , whereas catalyst
F (in which the said pore volume is less than 0.20 ml/g), is only
capable of removing 41 %w V+Ni after processing of the same amounts
of feed/kg catalyst, while, moreover, the space velocity is only 3.0
1.1. .h A comparable situation is found with catalysts G and H.
Catalyst G (in which~he said pore volume is more than 0.20 ml/g)
tO i8 still capable of~removing 51 %w V~i after processing 5 tons reed/kg
catalyst at a spnce velocity of 3,1 l,l .h , whereas catalyst H
(in which the said pore volume is less than 0.20 ml/g), is only capable
Or removing 42 %w V+Ni a~ter processing of the same amount Or ~eed/kg
catalyst at the same space velocity.
Comparison of the demetallization activities Or catalysts C
and D 3hows the favourable influence of the incorporation of phosphorus
in the catalysts.
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