Hydrocarbon conversion process and catalysts

A process for converting hydrocarbon oils into products of low average molecular weight and lower average boiling point comprising contacting a hydrocarbon oil at elevated temperature and pressure in the presence of hydrogen with a catalyst comprising a modified Y zeolite having a unit cell size below 24.45 .ANG., a degree of crystallinity which is at least retained at increasing SiO.sub.2 /Al.sub.2 O.sub.3 molar ratios, a water adsorption capacity (at 25.degree. C. and p/p.sub.o value of 0.2) of at least 8% by weight of modified zeolite and a pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total pore volume is made up of pores having a diameter of at least 8 nm, an amorphous cracking component, a binder and at least one hydrogenation component of a Group VI metal and/or at least one hydrogenation component of a Group VIII metal. The invention also relates to catalyst compositions suitable for use in said process.

FIELD OF THE INVENTION 
The present invention relates to hydrocarbon conversion processes and 
catalysts which can be used in such processes. The present invention also 
relates to compositions of matter suitable as catalyst or catalyst base in 
hydroprocessing, particularly in hydrocracking. 
BACKGROUND OF THE INVENTION 
Of the many hydroconversion processes known in the art, hydrocracking is 
becoming increasingly important since it offers product flexibility 
together with product quality. As it is also possible to subject rather 
heavy feedstocks to hydrocracking it will be clear that much attention has 
been devoted to the development of hydrocracking catalysts. 
Modern hydrocracking catalysts are generally based on zeolitic materials 
which may have been adapted by techniques like ammonium ion exchange and 
various forms of calcination in order to improve the performance of the 
hydrocracking catalysts based on such zeolites. 
One of the zeolites which is considered to be a good starting material for 
the manufacture of hydrocracking catalysts is the well-known synthetic 
zeolite Y as described in U.S. Pat. No. 3,130,007 issued Apr. 21, 1964. A 
number of modifications has been reported for this material which include, 
inter alia, ultrastable Y (U.S. Pat. No. 3,536,605 issued Oct. 27, 1970) 
and ultrahydrophobic Y (U.K. Patent Application GB-A-2,014,970, published 
Sept. 5, 1979). In general, it can be said that the modifications cause a 
reduction in the unit cell size depending on the treatment carried out. 
The ultrahydrophobic Y zeolites as described in GB-A-2,014,970 are also 
referred to in European Patent Application EP-B-28,938 published May 20, 
1981, and European Patent Specification EP-B-70,824 published Feb. 5, 
1986, as suitable components for hydrocracking catalysts. From said 
publications it appears that such zeolites have an intrinsically low water 
adsorption capacity. Water adsorption capacities below 5% (EP-B-28,938), 
respectively 8% (Specification EP-B-70,824) by weight of zeolite are 
considered to be the maximum levels acceptable and it is confirmed 
experimentally in EP-B-28,938 that a water adsorption capacity of 8.5% by 
weight on zeolite causes a drastic decrease in selectivity. 
In European Patent Application EP-A-162,733 published Nov. 11, 1985, 
zeolite Y components for hydrocracking catalysts are described which must 
possess a rather stringent pore diameter distribution which in essence 
means that at least 80% of the total pore volume is made up of pores 
having a diameter of less than 2 nm, and preferably at least 85% of the 
total pore volume is made up of pores having a diameter of less than 2 nm. 
In U.K. Patent Application GB-A-2,114,594 published Aug. 24, 1983, a 
process for the production of middle distillates is disclosed wherein use 
is made of catalysts comprising so-called expanded pore faujasitic 
zeolites. The pore expansion referred to in said patent specification has 
been obtained by firstly steaming the faujasitic zeolite at a temperature 
of at least 538.degree. C., in particular at a temperature above 
760.degree. C., followed by contacting the steamed faujasitic zeolite with 
an acid, preferably an acid having a pH less than 2. It should be noted 
that the degree of crystallinity retained in the expanded pore zeolite 
dramatically decreases at increasing amounts of acid used (see FIG. 3 of 
GB-A-2,114,594). Since the SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio 
substantially increases linearly with the amounts of acid used (see FIG. 
2) it appears that the crystallinity of the faujasitic zeolites treated 
according to the process described in GB-A-2,114,594 intrinsically 
decreases at increasing SiO.sub.2 /Al.sub.2 O.sub.3 molar ratios. 
It has now been found that the presence of certain modified Y zeolites 
together with an amorphous cracking component in hydrocracking catalysts 
gives an unexpected high selectivity to the desired product(s) combined 
with a significantly lower gas make than experienced thus far with 
catalysts based on Y zeolite. Also substantial amounts of polynaphthenic 
compounds present in the feed to be processed, which compounds are 
notoriously difficult to process, if at all, can be conveniently converted 
in the process according to the present invention. 
It has now been found that the presence of amorphous cracking components 
has a significant impact on the conversion of polynaphthenic compounds. 
The expression "polynaphthenic compounds" as used herein should be 
understood as relating to polynaphthenic compounds which as measured by 
mass spectroscopy have four or more rings in their respective structures 
which are predominantly condensed. Moreover, it was found that the quality 
of the product(s) was improved despite a lower hydrogen consumption. These 
improvements are even more remarkable since they can be achieved with 
catalysts showing a higher activity than thus far achievable with Y type 
zeolites. 
SUMMARY OF THE INVENTION 
The present invention relates to a process for converting hydrocarbon oils 
into products of lower average molecular weight and lower average boiling 
point comprising contacting a hydrocarbon oil at elevated temperature and 
pressure in the presence of hydrogen with a catalyst comprising a modified 
Y zeolite having a unit cell size below 24.45 .ANG., a degree of 
crystallinity which is at least retained at increasing SiO.sub.2 /Al.sub.2 
O.sub.3 molar ratios, a water adsorption capacity (at 25.degree. C. and a 
p/p.sub.o value of 0.2) of at least 8% by weight of modified zeolite and a 
pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total 
pore volume is made up of pores having a diameter of at least 8 nm, an 
amorphous cracking component, a binder and at least one hydrogenation 
component of a Group VI metal and/or at least one hydrogenation component 
of a Group VIII metal. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Preferably catalysts are used wherein between 10% and 40% of the total pore 
volume of the modified Y zeolite is made up of pores having a diameter of 
at least 8 nm. The pore diameter distribution is determined by the method 
described by E. P. Barrett, G. Joyner and P. P. Halenda (J. Am. Chem. Soc. 
73, 373 (1951)) and is based on the numerical analysis of the nitrogen 
desorption isotherm. It should be noted that inter-crystalline voids are 
excluded in the determination of the percentage of the total pore colume 
made up in pores having a diameter of at least 8 nm when said percentage 
is between 10% and 40%. 
It has been found that very good results in terms of performance and 
activity as well as conversion of unwanted polynaphthenic compounds can be 
obtained when modified Y zeolites are used having a water adsorption 
capacity of at least 10% by weight on zeolite, in particular between 10% 
and 15% by weight of zeolite. The water adsorption capacity of the 
modified Y zeolites present in the catalysts according to the present 
invention is measured at 25.degree. C. and a p/p.sub.o value of 0.2. In 
order to determine the water adsorption capacity the modified Y zeolite is 
evacuated at elevated temperature, suitably 400.degree. C., and 
subsequently subjected at 25.degree. C. to a water pressure corresponding 
to a p/p.sub.o value of 0.2 (ratio of the partial water pressure in the 
apparatus and the saturation pressure of water at 25.degree. C.). 
The unit cell size of the modified Y zeolites present in the catalyst 
compositions to be used in process according to the present invention is 
below 24.45 .ANG. (as determined by ASTM-D-3492, the zeolite being present 
in its NH.sub.4.sup.+ -form) and preferably below 24.40 .ANG., in 
particular below 24.35 .ANG.. It should be noted that the unit cell size 
is but one of the parameters which determine the suitability of modified Y 
zeolites. It has been found that also the water adsorption capacity and 
the pore diameter distribution as well as the crystallinity have to be 
taken into account in order to be able to obtain marked improvements in 
performance as referred to hereinbefore. 
As regards crystallinity it should be noted that the modified Y zeolites 
according to the present invention should at least retain their 
crystallinity (relative to a certain standard, e.g., Na-Y) when comparing 
crystallinity as a function of increasing SiO.sub.2 /Al.sub.2 O.sub.3 
molar ratio. Generally, the crystallinity will slightly improve when 
comparing modified Y zeolites with increasing SiO.sub.2 /Al.sub.2 O.sub.3 
molar ratios. 
The catalyst compositions to be used in the process according to the 
present invention suitably comprise 50-90% by weight of modified Y zeolite 
and amorphous cracking catalyst and 10-50% by weight of binder. Preferably 
the catalyst compositions comprise rather high amounts of modified Y 
zeolite: 60-85% by weight of modified Y zeolite and amorphous cracking 
component and 15-40% by weight of binder being particularly preferred. 
The process according to the present invention is suitably carried out by 
using a catalyst wherein the amount of modified Y zeolite ranges between 5 
and 95% of the combined amount of modified Y zeolite and amorphous 
cracking component. In particular, the process according to the present 
invention is carried out by using a catalyst wherein the amount of 
modified Y zeolite ranges between 10 and 75% of the combined amount of 
modified Y zeolite and amorphous cracking component. 
Suitably, silica-based amorphous cracking components can be used in the 
process according to the present invention. Preference is given to the use 
of silica-alumina as amorphous cracking component. The amount of silica in 
silica-based cracking components suitably comprises 50-95% by weight. Also 
so-called X-ray amorphous zeolites (i.e. zeolites having crystallite sizes 
too small to be detected by standard X-ray techniques) can be suitably 
applied as cracking components in the process according to the present 
invention. 
The binder(s) present in the catalyst compositions suitably comprise 
inorganic oxides. Both amorphous and crystalline binders can be applied. 
Examples of suitable binders comprise silica, alumina, clays and zirconia. 
Preference is given to the use of alumina as binder. 
Depending on the desired unit cell size the SiO.sub.2 /Al.sub.2 O.sub.3 
molar ratio of the modified Y zeolite will have to be adjusted. There are 
many techniques described in the art which can be applied to adjust the 
unit cell size accordingly. It has been found that modified Y zeolites 
having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio between 4 and 25 can be 
suitably applied as the zeolite component of the catalyst compositions 
according to the present invention. Preference is given to modified Y 
zeolites having a molar SiO.sub.2 /Al.sub.2 O.sub.3 ratio between 8 and 
15. 
Suitably, the catalyst compositions to be used in the process according to 
the present invention comprise one or more components of nickel and/or 
cobalt and one or more components of molybdenum and/or tungsten or one or 
more components of platinum and/or palladium. 
The amount(s) of hydrogenation component(s) in the catalyst compositions 
suitably range between 0.05 and 10% by weight of Group VIII metal 
component(s) and between 2 and 40% by weight of Group VI metal 
component(s), calculated as metal(s) per 100 parts by weight of total 
catalyst. The hydrogenation components in the catalyst compositions may be 
in the oxidic and/or the sulphidic form. If a combination of at least a 
Group VI and a Group VIII metal component is present as (mixed) oxides, it 
will be subjected to a sulphiding treatment prior to proper use in 
hydrocracking. 
Hydroconversion process configurations in accordance with the present 
invention are those wherein a substantial reduction in average molecular 
weight and boiling point can be accomplished by contacting the feed with a 
catalyst composition comprising a modified Y zeolite, an amorphous 
cracking component and a binder as described hereinbefore. 
Examples of such processes comprise single-stage hydrocracking, two-stage 
hydrocracking, series-flow hydrocracking as well as mild hydrocracking. 
It will be appreciated that the hydroconversion processes in accordance 
with the present invention can also be carried out suitably in bunker-type 
operations, i.e., by using reactor vessels allowing for periodical or 
intermittent catalyst removal and replenishment. Use can be made of the 
various bunker-techniques described in the art. 
Feedstocks which can be suitably applied in the process according to the 
present invention comprise gas oils, vacuum gas oils, deasphalted oils, 
long residues, catalytically cracked cycle oils, coker gas oils and other 
thermally cracked gas oils and syncrudes, optionally originating from tar 
sands, shale oils, residue upgrading processes or biomass. Combinations of 
various feedstocks can also be applied. 
It may be desirable to subject part or all of the feedstock to one or more 
(hydro)treatment steps prior to its use in the hydrocarbon conversion 
process according to the present invention. It is often found convenient 
to subject the feedstock to a (partial) hydrotreatment. When rather heavy 
feedstocks are to be processed it will be advantageous to subject such 
feedstocks to a (hydro) demetallization treatment. 
Suitable process conditions to be applied comprise temperatures in the 
range of from 250.degree. C. to 500.degree. C., pressures up to 300 bar 
and space velocities between 0.1 and 10 kg feed per liter of catalyst per 
hour (kg/1/h). Gas/feed ratios between 100 and 5000 N1/kg feed (normal 
liters at standard temperature and pressure per kilogram) can suitably be 
used. 
It has been found that at least 10% by weight of polynaphthenic components 
(either already present in the starting material or accumulated therein 
via recycle operation) can be converted in addition under the prevailing 
reaction conditions at a gross conversion level of at least 40% by weight 
per pass. 
Preferably, the hydroconversion process according to the present invention 
is carried out at a temperature between 300.degree. C. and 450.degree. C., 
a pressure between 25 and 200 bar and a space velocity between 0.2 and 5 
kg feed per liter of catalyst per hour. Preferably, gas/feed ratios 
between 250 and 2000 are applied. 
The catalysts to be used in the hydrocarbon conversion process according to 
the present invention, and in particular in the hydrocracking process 
appear to be very flexible as they are capable of producing product 
fractions with rather narrow boiling point ranges because of their 
inherent property of limited overcracking. Therefore, they can be used 
advantageously in various modes of operation dependent on the desired 
product slate. 
It is thus possible to use as feed a hydrocarbon oil fraction having a 
boiling point range slightly above the boiling point range of the product 
to be obtained in the process. However, substantially higher boiling feeds 
can also be used conveniently to produce materials of similar product 
boiling point range. For instance, a vacuum gas oil appears to be an 
excellent feedstock to produce middle distillates using the catalysts in 
accordance with the present invention but also naphtha can be produced in 
high yields. By adjusting, for instance, the operating temperature and/or 
the recycle cut-point (when operating in recycle mode) either middle 
distillate or naphtha will become the main product whilst retaining high 
selectivity with respect to the desired product. 
The present invention also relates to catalyst compositions comprising a 
modified Y zeolite having a unit cell size below 24.45 .ANG., a degree of 
crystallinity which is at least retained at increasing SiO.sub.2 /Al.sub.2 
O.sub.3 molar ratios, a water adsorption capacity (at 25.degree. C. and a 
p/p.sub.o value of 0.2) of at least 8% by weight of modified zeolite and a 
pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total 
pore volume is made up of pores having a diameter of at least 8 nm, an 
amorphous cracking component, a binder and at least one hydrogenation 
component of a Group VI metal and/or at least one hydrogenation component 
of a Group VIII metal, and wherein 50-90% by weight of the catalyst is 
made up of modified Y zeolite and amorphous cracking component and 10-50% 
by weight is made up of binder. Preference is given to catalyst 
compositions wherein 60-85% by weight of the catalyst is made up of 
modifed Y zeolite and amorphous cracking component and 15-40% by weight is 
made up of binder. 
Preferably, the catalyst compositions comprise modified Y zeolites wherein 
between 10% and 40% of the total pore volume is made up of pores having a 
diameter of at least 8 nm. The catalyst compositions preferably comprise 
modified Y zeolites having a water adsorption capacity between 10% and 15% 
by weight of modified zeolite. Suitably, the modified Y zeolites have a 
unit cell size below 24.40 .ANG., in particular below 24.35 .ANG.. 
The amount of modified Y zeolite in the catalyst compositions in accordance 
with the present invention preferably ranges between 10% and 75% of the 
combined amount of modified Y zeolite(s) and amorphous cracking component. 
Silica-based cracking components are preferred. The modified Y zeolite in 
accordance with the present invention has a SiO.sub.2 /Al.sub.2 O.sub.3 
molar ratio of from 4 to 25, in particular of from 8 to 15. 
The catalyst compositions in accordance with the present invention 
preferably comprise between 0.05 and 10% by weight of nickel and between 2 
and 40% by weight of tungsten, calculated as metals per 100 parts by 
weight of total catalyst. 
The ranges and limitations provided in the instant specification and claims 
are those which are believed to particularly point out and distinctly 
claim the instant invention. It is, however, understood that other ranges 
and limitations that perform substantially the same function in 
substantially the same manner to obtain the same or substantially the same 
result are intended to be within the scope of the instant invention as 
defined by the instant specification and claims. 
The present invention will now be illustrated by means of the following 
Examples.

EXAMPLE I 
(a) Preparation of catalyst. 
96.5 Grams of a modified Y zeolite having a unit cell size of 24.37 .ANG., 
a water adsorption capacity (at 25.degree. C. and a p/p.sub.o value of 
0.2) of 11.8% by weight, a nitrogen pore volume of 0.28 ml/g wherein 21% 
of the total pore volume is made up of pores having a diameter of &gt;8 nm 
and a loss of ignition (550.degree. C.) of 6.7% by weight is mixed with 
625.8 g amorphous silica-alumina (ex Akzo) with a loss on ignition of 
18.5% by weight. To this powdery mixture were added a slurry of 500 g of 
water and 191 g of hydrated aluminum oxide (boehmite, ex Condea) having a 
loss on ignition of 22% by weight and 7.5 g of acetic acid. After mulling 
the mixture obtained it was extruded in a Bonnot extruder provided with a 
die plate producing 1.5 mm extrudates. The extrudates obtained were dried 
at 120.degree. C. for a 2 hours and finally calcined for 2 hours at 
500.degree. C. The extrudates obtained had a water pore volume of 0.83 
ml/g. 
A nickel/tungsten solution was made up containing 107 g nickel nitrate 
solution (14% by weight of Ni), 76 g of water and 68 g of ammonium 
metatungstate (69.5% by weight of W). 25.2 Grams of the nickel/tungsten 
solution was diluted with water to 42 ml and used to impregnate 50 g of 
the extrudates described hereinbefore. Finally, the impregnated extrudates 
were dried at 120.degree. C. for 4 hours and calcined at 500.degree. C. 
for 1 hour. They contained 2.6% by weight of nickel and 8.2% by weight of 
tungsten. The ready catalyst contained 10.6% by weight of modified Y 
zeolite, 68.5% by weight of amorphous cracking component and 20.9% by 
weight of binder, on a dry metals free basis. 
(b) Hydrocracking experiments. 
The catalyst was described in Example Ia was subjected to a hydrocracking 
performance test involving a hydrotreated heavy vacuum gas oil having the 
following properties: 
______________________________________ 
C (% wt) 86.1 
H (% wt) 13.9 
S (ppm) 400 
N (ppm) 9 
d (70/4) 0.8277 
pour point (.degree.C.) 
36 (ASTM D-97) 
I.B.P. (.degree.C.) 
205.degree. C. 
10% wt rec. 360 
20% wt rec. 399 
30% wt rec. 427 
40% wt rec. 447 
50% wt rec. 465 
60% wt rec. 482 
70% wt rec. 500 
80% wt rec. 521 
90% wt rec. 544 
F.B.P. &gt;620 
______________________________________ 
The catalyst was firstly subjected to a presulphiding treatment by slowly 
heating in a 10% v H.sub.2 S/H.sub.2 -atmosphere to a temperature of 
370.degree. C. The catalyst was tested in a 1:1 dilution with 0.2 mm SiC 
particles under the following operating conditions: WHSV 1.45 kg.l.sup.1 
h.sup.-1, H.sub.2 S partial pressure 1.2 bar, total pressure 118 bar and a 
gas/feed ratio of 1,500 Nl kg.sup.-1. The experiment was carried out in 
once-through operation. The catalyst performance is expressed at 50% by 
weight conversion of 320.degree. C..sup.+ boiling point material in the 
feed after allowing the catalyst to stabilize. 
The following results were obtained: 
Temperature required (50% conv. of 320.degree. C..sup.+): 351.degree. C. 
Distribution of 320.degree. C..sup.- product (in % by weight) 
______________________________________ 
C.sub.1 -C.sub.4 
6 
C.sub.5 -140.degree. C. 
40 
140.degree. C.-320.degree. C. 
54 
______________________________________ 
The chemical hydrogen consumption amount to 0.7% by weight on feed. 
EXAMPLE II 
(a) Preparation of catalyst 
295 Grams of a modified Y zeolite having a unit cell size of 24.37 .ANG., a 
water adsorption capacity (at 25.degree. C. and a p/p.sub.o value of 0.2) 
of 11.8% by weight, a nitrogen pore volume of 0.28 ml/g wherein 21% of the 
total pore volume is made up of pores having a diameter of &gt;8 nm and a 
loss on ignition (550.degree. C.) of 6.8% by weight is mixed with 337 g of 
amorphous silica-alumina (ex Akzo) with a loss on ignition of 18.4% by 
weight. To this powdery mixture were added a slurry of 500 g of water and 
175 g of hydrated aluminum oxide (boehmite, ex Condea) having a loss on 
ignition of 21.4% by weight and 6.8 g of acetic acid. After mulling the 
mixture obtained, it was extruded in a Bonnot extruder provided with a die 
plate producing 1.5 mm extrudates. The extrudates were dried at 
120.degree. C. for 2 hours and finally calcined for 2 hours at 500.degree. 
C. The extrudates obtained had a water pore volume of 0.73 ml/g. 
A nickel/tungsten solution was made up containing 107.2 g of nickel nitrate 
solution (14% by weight of nickel), 76 g of water and 68.4 g of ammonium 
metatungstate (69.5% by weight of tungsten). 25.2 Grams of the 
nickel/tungsten solution was diluted with water to 36.5 ml and used to 
impregnate 50 g of the extrudates described hereinabove. After 
homogenizing the impregnated extrudates for 1 hour using a rolling device, 
the extrudates were dried for 1 hour at 120.degree. C. and calcined for 1 
hour at 500.degree. C. They contained 2.6% by weight of nickel and 8.2% by 
weight of tungsten. The ready catalyst contained 36.6% by weight of 
modified Y zeolite, 41.8% by weight of amorphous cracking component and 
21.6% by weight of binder, on a dry metals free basis. 
(b) Hydrocracking experiments 
The catalyst as described in Example IIa was subjected to a presulphiding 
treatment as described in Example Ib and thereafter tested in a 1:1 
dilution with 0.2 mm SiC particles under the operating conditions as 
described in Example Ib. 
The catalyst performance is expressed at 50% by weight conversion of 
320.degree. C..sup.+ boiling point material in the feed after allowing the 
catalyst to stabilize. 
The following results were obtained: 
Temperature required (50% conv. of 320.degree. C..sup.+): 334.degree. C. 
Distribution of 320.degree. C..sup.- product (in % by weight): 
______________________________________ 
C.sub.1 -C.sub.4 
9 
C.sub.5 - 140.degree. C. 
41 
140.degree.-320.degree. C. 
49 
______________________________________ 
The chemical hydrogen consumption amount to 0.9% by weight on feed. 
EXAMPLE III 
(a) Preparation of the catalyst 
A commercially available ammonium-ultra stable zeolite Y having a unit cell 
size of 24.57 .ANG., a sodium-oxide content of 0.21% %wt and a SiO.sub.2 
/Al.sub.2 O.sub.3 molar ratio of about 6 was subjected to an ion-exchange 
treatment with 0.2M aluminum sulphate for one hour under reflux 
conditions. Thereafter, the material thus treated was subjected to a 
calcination in the presence of steam for a period of one hour at 
700.degree. C. The calcined material obtained had a unit cell size of 
24.30 .ANG. and a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 6.85. 
The material obtained was then subjected to an ion exchange treatment with 
0.16M aluminum sulphate for one hour under reflux conditions followed by a 
treatment with 1M ammonium nitrate under the same conditions. This 
treatment was repeated once. The modified Y zeolite obtained had a unit 
cell size of 24.32 .ANG. and a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 
10.2. 
317 Grams of said modified Y zeolite having a unit cell size of 24.32 
.ANG., a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 10.2, a water 
adsorption capacity (at 25.degree. C. and a p/p.sub.o value of 0.2) of 
10.6% by weight, a nitrogen pore volume of 0.47 ml/g wherein 27% of the 
total pore volume is made up of pores having a diamter &gt;8 nm and a loss on 
ignition (550.degree. C.) of 21% by weight is mixed with 356 g of 
amorphous silica-alumina (ex Crosfield) with a loss on ignition of 30% by 
weight and 168 g of hydrated aluminum oxide (boehmite, ex Condea) having a 
loss on ignition of 25.8% by weight. A solution of 18.8 g of acetic acid 
and 342 g of water was added to this mixture. After mulling, the resulting 
mixture was extruded in a Bonnot provided with a die plate producing 1.5 
mm extrudates. The extrudates were dried for 2 hours at 120.degree. C. and 
calcined for 2 hours at 500.degree. C. The extrudates obtained had a water 
pore volume of 0.71 ml/g. A nickel/tungsten solution was made up 
containing 214 g of nickel nitrate solution (14% by weight of nickel), 150 
g of water and 136.7 g of ammonium metatungstate (69.5% by weight of 
tungsten). 65.7 Grams of the nickel/tungsten solution was diluted with 
water to 93 ml and used to impregnate 131 g of the extrudates described 
hereinabove. After homogenizing the impregnated extrudates for 1 hour 
using a rolling device, the extrudates were dried for 2 hours at 
120.degree. C. and finally calcined at 500.degree. C. for 1 hour. They 
contained 2.6% by weight of nickel and 8.2% by weight of tungsten. The 
ready catalyst contained 37.7% by weight of modified Y zeolite, 42.3% by 
weight of amorphous cracking component and 20.0% by weight of binder, on a 
dry metals free basis. 
(b) Hydrocracking experiments 
The catalyst as described in Example IIIa was subjected to a presulphiding 
treatment as described in Example Ib and thereafter tested as described in 
Example IIb. 
The catalyst performance is expressed at 50% by weight conversion of 
320.degree. C..sup.+ boiling point material in the feed after allowing the 
catalyst to stabilize. 
The following results were obtained: 
Temperature required (50% conv. of 320.degree. C..sup.+): 330.degree. C. 
Distribution of 320.degree. C..sup.- product (in % by weight): 
______________________________________ 
C.sub.1 -C.sub.4 
7 
C.sub.5 - 140.degree. C. 
40 
140.degree. C.-320.degree. C. 
53 
______________________________________ 
The chemical hydrogen consumption amounted to 0.8% by weight on feed. 
Comparative Example A 
(a) Preparation of catalyst 
113.8 Grams of a commercialy available ultra-stable Y zeolite having a unit 
cell size of 24.56 .ANG., a water absorption capacity (at 25.degree. C. 
and a p/p.sub.o value of 0.2) of 24% by weight and a nitrogen pore volume 
of 0.38 ml/g wherein 8% of the total pore volume is made up of pores 
having a diameter of &gt;8 nm and a loss on ignition (550.degree. C.) of 21% 
by weight was mixed with 626 g of amorphous silica-alumina (ex Akzo) 
having a loss on ignition (550.degree. C.) of 18.5% by weight. To this 
powdery mixture were added a slurry of 500 g of water and 191 g of 
hydrated aluminum oxide (boehmite, ex Condea) having a loss on ignition of 
22% by weight and 7.5 g of acetic acid. After mulling the mixture 
obtained, it was extruded in a Bonnot extruder provided with a die plate 
producing 1.5 mm extrudates. The extrudates were dried for 2 hours at 
120.degree. C. and finally calcined for 2 hours at 500.degree. C. The 
extrudates obtained had a water pore volume of 0.80 ml/g. A 
nickel/tungsten solution was made up containing 107.3 g of nickel nitrate 
(14% by weight of nickel), 76 g of water and 68.4 g of ammonium 
metatungstate (69.5% by weight of tungsten). 40 Ml of a solution 
containing water and 25.2 g of the nickel/tungsten solution was used to 
impregnate 50 g of the extrudates described hereinabove. After 
homogenizing the impregnated extrudates for 1 hour using a rolling device, 
the extrudates were dried for 2 hours at 120.degree. C. and calcined for 1 
hour at 500.degree. C. They contained 2.6% by weight of nickel and 8.2% by 
weight of tungsten. The ready catalyst contained 12.2% by weight of 
zeolite, 67.3% by weight of amorphous cracking component and 20.5% by 
weight of binder, on a dry metals free basis. 
(b) Hydrocracking experiments 
The catalyst as described in Comparative Example A (a) was subjected to a 
presulphiding treatment as described in Example I b and thereafter tested 
as described in Example I b. 
The catalyst performance is expressed at 50% by weight conversion of 
320.degree. C..sup.+ boiling point material in the feed after allowing the 
catalyst to stabilize. 
The following results were obtained: 
Temperature requirement (50% conv. of 320.degree. C..sup.+); 361.degree. C. 
Distribution of 320.degree. C..sup.- product (in % by weight); 
______________________________________ 
C.sub.1 -C.sub.4 
9 
C.sub.5 - 140.degree. C. 
56 
130.degree. C.-320.degree. C. 
35 
______________________________________ 
The chemical hydrogen consumption amounted to 1.0% by weight on feed 
Comparative Example B 
(a) Preparation of catalyst 
379.3 Grams of a commercially available ultra-stable Y-zeolite having a 
unit cell size of 24.56 .ANG., a water adsorption capacity (at 25.degree. 
C. and a p/p.sub.o value of 0.2) of 24% by weight and a nitrogen pore 
volume of 0.38 ml/g wherein 8% of the total pore volume is made up of 
pores having a diameter of &gt;8 nm and a loss on ignition (550.degree. C.) 
of 21% by weight was mixed with 368 g of amorphous silica-alumina (ex 
Akzo) having a loss on ignition (550.degree. C.) of 18.5% by weight. To 
this powdery mixture was added a slurry containing 191.1 g of hydrated 
aluminum oxide (boehmite, ex Condea), 500 g of water and 7.5 g of acetic 
acid. After mulling the mixture obtained, it was extruded in a Bonnot 
extruder with a die plate producing 1.5 mm extrudates. The extrudates were 
dried for 2 hours at 120.degree. C. and finally calcined for 2 hours at 
500.degree. C. The extrudates obtained had a water pore volume of 0.71 
ml/g. 
50 Grams of the extrudates thus obtained were impregnated with 36 ml of a 
solution comprising water and 25.2 g of a solution made up of 107.2 g of 
nickel nitrate (14% by weight of nickel), 76 g of water and 68.3 g 
ammonium metatungstate (69.5% by weight of tungsten). After homogenizing 
the impregnated extrudates were dried for 2 hours at 120.degree. C. and 
calcined for 1 hour at 500.degree. C. They contained 2.6% by weight of 
nickel and 8.2% by weight of tungsten. The ready catalyst contained 40.4% 
by weight of zeolite, 39.2% by weight of amorphous cracking component and 
20.4% by weight of binder, on a dry metals free basis. 
(b) Hydrocracking experiments 
The catalyst as described in Comparative Example B (a) was subjected to a 
presulphiding treatment as described in Example I b and thereafter tested 
as described in Example I b. 
The catalyst performance is expressed at 50% by weight conversion of 
320.degree. C..sup.+ boiling point material in the feed after allowing the 
catalyst to stabilize. 
The following results were obtained: 
Temperature required (50% conv. of 320.degree. C..sup.+): 338.degree. C. 
Distribution of 320.degree. C..sup.- product (in % by weight): 
______________________________________ 
C.sub.1 -C.sub.4 
22 
C.sub.5 - 140.degree. C. 
58 
140.degree. C.-320.degree. C. 
20 
______________________________________ 
The chemical hydrogen consumption amounted to 1.2% by weight on feed. 
It will be clear that the catalysts in accordance with the present 
invention are more active but also more selective than catalysts based on 
known ultra-stable Y zeolites. Also the chemical hydrogen consumption is 
slightly reduced.