Molecular sieve abstract
Method of activating a catalyst composite comprising particles
of a catalytic metals-free crystalline zeolitic molecular sieve
dispersed in a gel matrix comprising silica-alumina, a Group VI
hydrogenating component and a Group VIII hydrogenating component,
which method comprises heating said catalyst composite in an oxygen-containing
gas stream at 1200.degree. to 1600.degree. F. for 0.25 to 43 hours,
and the catalyst composite so activated.
Molecular sieve claims
What is claimed is
1. A hydrotreating process, which comprises contacting a hydrocarbon
feed in a reaction zone under hydrotreating conditions with hydrogen
and a catalyst comprising:
A. a gel matrix comprising:
a. at least 15 weight percent silica,
b. alumina, in an amount providing an alumina-to-silica weight
ratio of 15/85 to 80/20
c. nickel or cobalt, or the combination thereof, in the form of
metal, oxide, sulfide, or any combination thereof, in an amount
of 1 to 10 weight percent of said matrix, calculated as metal,
d. molybdenum or tungsten, or the combination thereof, in the form
of metal, oxide, sulfide or any combination thereof, in an amount
of 5 to 25 weight percent of said matrix, calculated as metal;
B. a crystalline zeolitic molecular sieve substantially in the
ammonia or hydrogen form, substantially free of any catalytic loading
metal or metals, said sieve further being in particulate form and
being dispersed through said matrix;
said catalyst composite being further characterized by an average
pore diameter below 100 Angstroms and a surface area above 200 square
meters per gram;
said catalyst composite being further characterized by hydrocracking
activities and stabilities developed therein by heating said catalyst
composite in an oxygen-containing gas stream at temperatures in
the range 1200.degree. F. to 1600.degree. F. for 0.25 to 48 hours;
and recovering hydrotreated products from said reaction zone.
2. A process as in claim 1 further characterized in that said gel
matrix further comprises a Group IV component.
3. A process as in claim 2 further characterized in that said Group
IV component is titania.
4. A process as in claim 1 further characterized in that said gel
matrix comprises nickel and tungsten, in the form of metal, oxide,
sulfide, or any combination thereof.
Molecular sieve description
INTRODUCTION
In said application Ser. No. 749836 filed on Aug. 2 1968 for
"Hydrotreating Catalyst and Process", there is described
a novel and unusually effective hydrofining-hydrocracking catalyst.
Said catalyst comprises a crystalline zeolitic molecular sieve component
substantially free of any catalytic metal or metals, a silica-containing
gel component, a Group VI hydrogenating component, and a component
selected from titanium, zirconium, thorium, hafnium, and compounds
thereof. It has now been found that catalyst of this general type,
either with or without a Group IV component, can be even further
improved in various respects by a novel heat treatment procedure,
which serves both to activate and stabilize the catalyst. Said heat
treatment procedure, hereinafter for convenience called an activation
or thermactivation treatment or procedure, is applied to the total
catalyst composite, following dispersion of the crystalline zeolitic
molecular sieve component in the gel matrix.
STATEMENT OF INVENTION
In accordance with the present invention catalysts of the aforesaid
type are thermactivated in an oxygen-containing gas stream at temperatures
in the range 1200.degree. to 1600.degree. F., preferably 1250.degree.
to 1400.degree. F., for 0.25 to 48 hours. The oxygen-containing
gas stream, which may be air, preferably is as dry as practicable.
The improved results obtainable with the process of the present
invention are optimized as the gas stream becomes extremely dry;
although for most practical purposes the gas stream need be only
as dry as ambient air, greater dryness is preferred. Those skilled
in the art will be aware of various methods for drying the gas stream
to any desired extent.
Although the process of the present invention is applicable to
activation of catalysts of the aforesaid type with a wide range
of silica content, it is especially useful with such catalysts that
contain less than 40 weight percent silica in the total catalyst,
and less than 35 weight percent silica in the catalyst matrix.
Further in accordance with the present invention there is provided
the method of activating a catalyst composite comprising:
A. A gel matrix comprising:
A. at least 15 weight percent silica,
b. alumina, in an amount providing an alumina-to-silica weight
ratio of 15/85 to 80/20
c. nickel or cobalt, or the combination thereof, in the form of
metal, oxide, sulfide or any combinaton thereof, in an amount of
1 to 10 weight percent of said matrix, calculated as metal,
d. molybdenum or tungsten, or the combination thereof, in the form
of metal, oxide, sulfide or any combination thereof, in an amount
of 5 to 25 weight percent of said matrix, calculated as metal;
B. A crystalline zeolitic molecular sieve substantially in the
ammonia or hydrogen form, substantially free of any catalytic loading
metal or metals, said sieve further being in particulate form and
being dispersed through said matrix;
said catalyst composite being further characterized by an average
pore diameter below 100 Angstroms and a surface area above 200 square
meters per gram; which method comprises heating said catalyst composite
in an oxygen-containing gas stream at temperatures in the range
1200.degree. to 1600.degree. F. for 0.25 to 48 hours.
Further in accordance with the present invention there is provided
a catalyst composite comprising:
A. A gel matrix comprising:
a. at least 15 weight silica,
b. alumina, in an amount providing an alumina-to-silica weight
ratio of 15/85 to 80/20
c. nickel or cobalt, or the combination thereof, in the form of
metal, oxide, sulfide or any combination thereof, in an amount of
1 to 10 weight percent of said matrix, calculated as metal,
d. molybdenum or tungsten, or the combination thereof, in the form
of metal, oxide, sulfide or any combination thereof, in an amount
of 5 to 25 weight percent of said matrix, calculated as metal;
B. A crystalline zeolitic molecular sieve substantially in the
ammonia or hydrogen form, substantially free of any catalytic loading
metal or metals, said sieve further being in particulate form and
being dispersed through said matrix;
said catalyst composite being further characterized by an average
pore diameter below 100 Angstroms and a surface area above 200 square
meters per gram; said catalyst composite being further characterized
by hydrocracking activities and stabilities developed therein by
heating said catalyst composite in an oxygen-containing gas stream
at temperatures in the range 1200.degree. to 1600.degree. F. for
0.25 to 48 hours.
The gel matrix of the aforesaid catalyst composite additionally
may comprise titanium, zirconium, thorium, hafnium, or any combination
thereof, in the form of the metal, oxide, sulfide or any combination
thereof, in an amount of 1 to 10 weight percent of said matrix,
calculated as metal.
The reference to a crystalline zeolitic molecular sieve "substantially
free of any catalytic loading metal or metals" means that the
molecular sieve contains no more than 0.5 weight percent of catalytic
metal or metals, based on the sieve. The catalytic metal or metals
include the Group VI and VIII metals, excluding sodium.
EXAMPLES
The following examples are given for the purpose of further illustrating
the process and catalyst of the present invention, without limiting
the scope thereof.
EXAMPLE 1
The catalyst was prepared by the following steps, using sufficient
quantities of the various starting materials to produce the above-indicated
weight percentages of the components of the final catalyst:
1. An aqueous acidic solution was prepared, containing AlCl.sub.3
TiCl.sub.4 NiCl.sub.2 and acetic acid.
2. Three alkaline solutions were prepared: (1) a sodium silicate
solution; (2) a sodium tungstate solution; and (3) an ammonia solution
containing sufficient excess ammonia so that upon combining the
alkaline solutions with the acidic solution coprecipitation of all
of the metal-containing components would occur at a neutral pH of
about 7.
3. The acidic and alkaline solutions were combined, and coprecipitation
of all of the metal-containing components of those solutions occurred
at a pH of about 7 resulting in a slurry.
4. Linde "Y" crystalline zeolitic molecular sieve in
finely divided form was added to the slurry.
5. The molecular sieve-containing slurry was filtered to produce
a molecular sieve-containing hydrogel filer cake, which was washed
repeatedly with dilute ammonium acetate solution to remove sodium
and chloride ionic impurities from both the hydrogel and the molecular
sieve contained therein.
6. The molecular sieve-containing hydrogel was dried in an air-circulating
oven and then was activated in flowing air at 950.degree. F. for
5 hours.
The finished catalyst was characterized by a surface area of about
400 M.sup.2 /g., a pore volume of about 0.4 cc./g., an average pore
diameter of about 40 Angstroms, and a molecular sieve component
substantially free of catalytic metals; that is, substantially all
of the nickel, tungsten and titanium in the catalyst was located
in the gel portion of the catalyst rather than in the molecular
sieve component thereof.
EXAMPLE 2
A cogelled catalyst (Catalyst B), of exactly the same composition
as Catalyst A of Example 1 was prepared. The catalyst was prepared
in exactly the same manner as Catalyst A of Example 1 except that
upon completion of the activation at 950.degree. F. for 5 hours
the catalyst was further activated at 1275.degree. F. for 2 hours.
The finished catalyst was characterized by a surface area of about
350 M.sup.2 /g., a pore volume of about 0.4 cc./g., an average pore
diameter of about 40 Angstroms. The molecular sieve component remained
substantially free of catalytic metals.
EXAMPLE 3
A cogelled catalyst (Catalyst C, a comparison catalyst) was prepared.
The composition was similar to that of Catalyst A of Example 1 except
that it contained only 10 weight percent of crystalline zeolitic
molecular sieve and the weight percentages of the other components
were proportionally adjusted. Catalyst C was prepared in exactly
the same manner as Catalyst A of Example 1 including a final activation
treatment in flowing air at 950.degree. F. for 5 hours. |