Note: Descriptions are shown in the official language in which they were submitted.
j,
0~6 ~ 4
1 This invention relates to a catalyst composition,
2 a method of making the catalyst, and its use in the c~talytic
3 conversion of hydrocarb~n oils.
4 Various processes such as cracking, hydrocracking,
etc. are known for the conversion of hydrocarbons to lower
6 molecular weight productsO Illustrative of "fluid" catalytic
7 convercion processes is the fluid catalytic cracklng process
8 w~erein suitably preheated high molecular weight hydrocarbon
9 liquids and vapors are contacted with hot, finely-divided,
0 ~olid catalyst particles, either in a fluidized bed reactor
11 or in an elongated riser reactor~ and maintained at an ele-
12 vated temperature in a fluidized or dispersed state for a
13 period of time sufficient to effect the desired degreè of
14 cracking to lower molecular weight hydrocarbons.
In the catalytic process, ~ome non-volatile car-
6 bbnaceous material, or "coke", is deposi~ed on thè catalyst
7 particles. As coke builds u~ on ~he catalyst, the activity
8 of the catalyst for cracking and the select~vity of the cata-
9 lyst for producing desirab~e produc~s diminish. The catalyst
~articles may recover a major proportion of their original
21 activity by removal of most of the coke by a suitable regen-
22 eration processO Catalyst regeneration is acco~plished by
23 burning the coke deposits from the ca~alyst surface wi~h an
24 oxygen-containing gas, such as air. Many regenerationitech-
2s niques are practiced commercially whereby a significant res-
26 toration of ca~alyst activity is achieved. The burning of
27 coke deposits from the catalysts requires a large volume of
28 oxygen or air and produces subst ntial quantities of CO and
29 C02. Ordinarily, the regeneration is conducted at a temper-
ature ranging from abou~ 1050 to about 1250F. The effect
31 of any increase in tempera~ure is reflected in an i~creased
32 rate of combustion of carbon and a more complete removal of
."' -
~
. . ~ , ., : ,
:
.
. . -. , . .: .
.. , .. ., . , ; .:
-'~
~0~ 34
1 carbon, or coke, from the catalyst particles.
2 A major problem often encountered in the practice
3 of fluid catalyst regeneration is the phenomenon known as
4 "afterburning", which is descriptive of the further combus-
tion of C0 to C02. The operators of fluid catalyst regenera-
6 tors avoid afterburning becaw3e it could lead ~o very high
7 temperatures which are damaging to equipment and possibly to
8 the catalyst particlesO ~r
9 - More recently9 as operators have soug~t to raise
0 regenera~or temperatures for various reasons, elaborate ar-
11 rangemen~s have also been developed for control of regener-
12 ator temperatures at the point of incipient afterburning by
13 suitable means for control of the oxygen supplied to t~e re-
14 generator. ~owever, with the control of afterburning, the
flue gas ~rom catalyst regenerators usually contains very
16 little oxygen and a substantial quantity of C0 and C02. In
7 order to substantially eliminate the C0 from the flue gas and
18 to recover heat energy from the combustion o C0 to C0~, the
19 regenera~or flue gas is generally sent to a C0 boiler~where-
in the combustion of C0 is performed.
21 There has appeared in the literature, vario~s tech-
22 nlques for substantially eliminating both uncontrolled`after-
23 burning and the presence of C0 in the regener~tor effluent
24 flue gas. These techniques generally involve ~he ùse of
relatively high regeneration tempera~ure~, e.g., 1275-
. I .
26 1400F., and the presence of relatively high concentrations
; 27 o~ 2 in the regenerator so that there i9 substantially
. , .
complete combustion of the spent catalyst coke to C02 in
the regeneration vessel.
It has also been dlsclosed in the li~erature that
~ 31 the presence of CO in the regenerator e~fluent gas from ~
i 32 catalytic cracklng operation can be substantially reduced by
.. .. . . . . .
: . .
~0'~8~
. ~ .
1 incorporating a small amount of a CO oxidation promoter in
2 the cracking ca~alyst composition. ~or example, cracking
3 catalyst composites consisting of a crystalline aluminosili-
4 cate zeolite~ a silica-alumina matrix and a small amount of
platinum or palladium are known to produce relatively small
6 amounts of CO during the regeneration thereof. Catalysts
7 prepared in accordance with ~he présent invention have im~
8 proved characteristics as compared to the prior art cracking
9 catalysts.
A hydrocarbon conversion catalyst for promoting
11 the oxidation of carbon monoxide during regeneration of the
; 12 catalyst by the burning of coke therefrom has been dis-
13 covered. This catalyst comprises (a) particles o~ a porous
4 oxide support containing a CO oxidation promoter, (b) a
crystalline aluminosilicate zeolite, and (c) a porous oxide
16 matrix material.
7 In one embodiment of ~hi~ invention ~he hydro~ar-
13 bon conversion catalyst comprises (a) the ultra-stable variety
19 of the Y-type crys~alline aluminosilicate zeolite con~aining
a CO oxidation promoter, (b) a rare earth metal-containing
21 zeolite, and (c) an inorganic porous oxide matrix material.
22 The catalyst of the invention comprises a metaI or
23 compound thereof whlch promotes the combustion of CO to CO2
24 under conditions which are employed to regenerate the spent
catalyst by burning the coke depo~ited thereon in the pres-
26 ence of oxygen~ Accordingly, the catalyst will contain one
27 or more metals (or compounds thereof) selected from Periods
28 5 and 6 of Group VIII of the Periodic Table ~Handbook`of
29 Chemistry and Physics, 38th Ed., 1957), rhenium, chromium
and mangane~e or their compounds. Specific examples of
31 such metals include platinum9 palladium, rhenium, irid~um,
32 ruthenium, rhodium, 09mium, manganese, etc. The aforedes-
- 4 -
;'' '. ' ' ,,
.; .. . . . . . . ..
6 ~ ~
l cribed metals may also be pre~ent in the oxidized state of
2 an oxide, sulfide, or other.
3 The inorganic porou~ oxide used as a base and/or
4 matrix in the catalyst composition of th~ i~ventlon will in-
clude any of the readily available porous materials such as
6 alumina, boria, silica, chrom:ia, magnesla, zirconia, titania,
7 the like, and mixtures thereo:E. These materials may also
8 include one or more of the various well known clay~ such as
9 montmorillonite, kaolin, halloysite, bentonite, a~tapulgite,
,
and the l~ke. Preferably, the inorganic porous oxide will
ll be one or more of the conven~ional siliceous varietie~ con-
12 taining a major amount of silica and a mlnor amount of an
13 oxide o~ at least one metal in Groups II-A, III-~ and IV-B
lA of the Periodic Table (Handbook of Chem~stry and Physics,
lS 38th Ed., 1957). Representative materials include sllica-
16 al~mina, siliea-magnesia, silica-zirconia3 silica-thoria,
17 ~ilica-titania, silica-alumina-zirconia, magnesia, etc. ; .
18 Generally, alumina is preferred as the inorganic porous
l9 oxide used as a suppor~ for ~he CO oxida~ion promoter, while
silica-alumina is generally pre~erred as the inorgani~ porous :-
2l oxide matrix material. As is generally know~, the~e'mater-
22 ials are typically prepared from silica hydrogel or ~yidrosol, :~
23 which is mi~ed with alumina to secure the de~ired sillca-
24 alumina eompasition. The alumina content will typically
range from about 5 to 40 wt, % with the preferred comE~08i-
26 tion having an alumina content of about 10 to 35 wt. ~t..
27 Various procedures are described in the literature fo~ mak-
28 ing silica-alumina, e.gO, U.S~ Patent NosO 2,908,635 and
29 2,844,523-
In addition to the above, ~he inorganic porous
31 oxide used as a base or support for the CO oxidation pro- :
32 moter may aLso comprise wha~ are commonly known as "ultra-
.
~ ' ' ' . .
:,. . . . . .
, . . . .. .
'' ~O~
l stable" faujasite or Y-type zeolite. These ultra-stable
2 zeolites are well known and conventionally used in various
3 conversion processes. They are described, for example, in
4 U.S. Patents 3,133,006; 3,293~1~2 and 3,402,996 and the
S publication, Society of Chemical Engineering (London)
6 Monograph Mole~ular Sieves, pp. 186 ~1968) by C. V. McDanlel
7 and P. K. Maher. In general, "ultra-stable" refers to a Y-
8 typa zeolite which is highly resistant to degradat~on of
9 crystallinity by high temperatures and steam treatment and
is characterized by an R20 content (where R is Na, K, or any
11 other alkali metal ion) of less than 1 wt. % and a unit cell
12 slze less than 24.50~ (usually in the range of 24.2 to
l3 24.45A) and an SiO2/A1203 mol ratio in the range of 3.5-7
~; 14 or highqr. The ultra-stable form of the Y-type zeolite is
obtained primarily by the virtual elimination of the alkali
r - .
l6 metal ion and the resulting uni~ cell shrinkage during the
7 alkali metal removal steps. In other words, the ultra-
18 stable zeolite is identified both by the smaller unit rell
l9 and he lack of alkali me~al in the cry~al ~tructureO
As is generally known, the ultra-s~able for~ of
21 the Y-type zeolite can be prepared by successively base-
22 exchanging a Y~type zeolite with an aqueous solution of an
23 ammonium salt, sùch as ammonium nitrate, until the alkali
24 metal content of the Y~type zeolite is reduced to less than
about S wt. %. The base-exchanged zeolite is ~hen calcined
2h at a temperature of 1000F. to 1500F. for several hours,
27 cooled and thereafter again successively base-excha~ged with
:~ .
28 an aqueous solution of an 8mmonium salt until the alkali
29 metal content is reduced to less than 1 wt. %, followed by
3~ washing and calcining ag~in at a temperature of 1000 to
, . . .
3i 1500F. to produce the ultra-stable zeolite Y. This sequence
32 Of ion exchange and heat treatment results in the vir~ua~
- 6 -
:
.,
': '`- '
;. ~ ,
1046484
1 elimination of the alkali metal content of the origlnal
2 zeolite and results in unit cell shrinkage which are believed
3 to ~ead to the ultra high stab~ility of the resultant ~-type
4 zeolite.
The crystalline aluminosilicate zeolltes uæed as
6 the zeolite co~ponent in the catalyst composition of t~e
7 present i~vention are well known and conventionally used in
8 hydr~carbon convers~n processes. The zeolites are charac-
9 terized by their highly ordered crystalline structure and
0 uniformly dimensioned pores, and are distinguishable from
11 each other on the basis of composition, crystal struct~re, ..
12 adsorption properties, and the like In general, these
13 zeolites will have uniform pore openings of about 3-15 Ang-
14 strom units, preferably about 6-13 Angstrom units. T~ese
values refer to the effective pore diameter of thé pore
;: 16 openings, i.e., the diamet~ a~ the conditions of use~cap-
17 sble of substantially admitting entry to smaller size~mole-
18 cules while subs.tantially excluding larger size molecules.
19 A number of naturally occurring crystalline alum-` .
inosilicate zeolites or "molecular sieves" are known and in- ~:
21 clude such materials as faujasite, mordenite, erionitë,
22 chabazite, and the like. Synthetically produced zeolites or
23 "molecular sieves" are also well known and include 8UC~ '~
~ 24 materials as zeolite A (U.S. 2,882,243), zeolite X (U. S.
: 25 ~,882,244), zeolite K-G (U.S. 3,055,654), zeolite ZK-5
26 (U.S. 3,247,195), zeolite Y (U.S. 3,130,007~, etc. Pre-
27 ferred zeolites include synthe~ic faujasite or zeolit`es X
28 and Y, with particular preference being accorded zeol~te Y.
~ For use in hydrocarbon conversion processes such
30 as catalytic cracking, it is desirable to reduce the initial
31 alkali metal content of the crystalline aluminosilicate zco-32 lites by replacing their alkali metal content with other
: - 7 -
..
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34
1 metals or hydrogen-containing components which promo~e the
2 desired conversion reaction. Typically, the alkali metal,
3 e.g., sodium, content is reduced to levels below 10 weight
4 percent, preferably below 4 weight percent and more prefer-
ably below 2 weight percent. Reduction of alkali metal con-
~ tent is readily accomplished iin accordance with well known
7 techniques by ion-e~change procedures wherein a desired
8 cation is introduced into the zeolitic structure to rë'place
the alkali metal cation initially presentO Desirabl~''cations
lQ include calcium, magnesium, hydrogen9 lithium, manganese,
11 lan~hanum, cerium, and mixtures of ~he rare earth metals,
12 etc. The rare earth metal cations are particularly p~e-
13 ferred. "
14 A wide variety of rare earth compounds can be em-
ployed as the source of rare earth ions~ Operable compound~
16 include rare earth chlorides, bromides, iodides, nitr'~tes,
.;
17 acetates, sulfates, formates, and the likeO The only limita-
18 tion on a particular rare ear~h metal salt or salts employed
9 is that it ~e su~ficiently soluble in the fluid medium in
2Q which it is used to give the necessary rare earth'ion`'trans-
21 fer. The preferred rare earth salts are the chlorides,
22 ni~rates, and sulfates. Representative of the rare earth
23 metals are cerium~ lanthanum, praseodymium, neodymium, pro-
24 methium, samarium, europium, gadolinium, terbium, dysprosium,
holmium, erbium, yttrium, thulium9 scandium, and lutecium
2\6 The rare earth metal salt employed can either be ~he salt
27 of a single rare earth metal or mixtures of rare earth'met~ls,
28 such as rare earth chlorides or didymium chlorldes. A's here-
29 inafter referred to, a rare earth chloride solution is a
.,
mixture of rare earth chlorides consisting ess~ntiall~ of
i 31 the chlorides of lanthanum, cerium, neodymium, and praseo-
32 dymium with minor amount~ of samarium9 gadolinium and
:
~ - 8 -
' , .
,
,. . . ... ~ ~.. ...
:: .
~ 0~6;~ ~
1 yttrium. Rare earth chloride solutions are commercially
2 available such as a mixture containing the chlorides of rare
3 earth having the approximate composition cerium (as CeO2)
4 48 percent by weight, lanthan~lm (as La203) 24 percent by
weight, neodymium (as Nd203) 1.6 percen~ by weight, praseody- :
6 mium (as Pr2O3) 5 percent by weight, and lesser amounts o~
7 samarium, gadolinium~ and other rare earth oxides. In
8 accordance with a preferred embodiment of this inven~ion,
9 at leas~ a portion of the alkal~ metal content of the zeo-
lite component of the catalyst composition i~ replaced with
ll - rare.earth metal cations. The rare earth metal content o~ .
12 the zeolite may range from 0 to 22 wt. % as oxides based on
3 the weight of the rare earth met.al-cvntaining zeolite. Pre- ~
4 ferably, the rare earth metal content of the zeolits will be . ~.
in the range o~ 14 to 22 wt. % expressea as oxidés. .
16 As with other exchangeable metal ions, the rare
17 earth metal is pre~erably incorporated into the crystalline
18 aluminosilicate zeolite by ion-exchange methods well ~nown
19 in the art. In a typical method, an alkali metal crystalline
aluminosilicate is base e~changed by contacting with a 5-10%
21 (wt.) rare earth chloride solution at 130-190F. for 2-24
22 hours, filtering, drying and:calcining at 750-1200,F. for
?3 0..5-2.0 hours in ambient air. To achieve higher leveIs of
24 exchange the process may be repeated. Other suitable methods
have also been descri~ed in the patent and general liter-
26 ature. The rare earth metal content o the crystalline
27 aluminosilicate zeolite will generally be in the rangè of
23 0-22 weight percent, preferably in the range o 14-2~2 wei~h~
2~ percent based on the weight of the zeolite. ~ ~`
The aforedescribed CO oxidation promoter which i~
31 incorporated into ~he ultra-stable Y-type æeolite is pre-
32 pared by known techniques 9uch as ion exch~nge, impregna-
_ g _
. . . .
j
il~4~i48~
1 tion, and v~por deposition. Preferably, the C0 o~idation
2 promoter is supported on the ultra-stable zeolite by impreg-
nation or ion exchange with a solution of a compound of one
4 or mo~ of the aforementioned metals in an amount sufficient
to provide the ~esired concentration. For example, an
aqueous solution of palladium nitrate and/or chloroplatinic
7 acid and/or platinum tetra-amine dichloride may be contacted
8 with the zeolite to produce a slurry which may thereafter
9 be iltered, dried, calcined, and/or pre-reduced with hydro-
gen or other suitable reducing agents. The ultra-sta~le
11 Y-type zeolite will generally contain 500 to 5000 ppm, pre-
12 ferably lO00 to 3500 ppm, of the C0 oxidation promoteP (on
13 a metal basis) where said ppm are based on the weigh~-~of ~he
14 CO oxid~tion promoter-containing ultra-stable Y-type zeolite
For use in petroleum hydrocarbon conversion such
16 as catalytic cracking operations~ it is important tha~ the
17 concentration o~ the components be adjusted to give maximu~
18 cracking to desirable products during the cracking opëration
19 an~ maximum converslon to C02 during the regeneration opera-
tion. In other words, the amount of CO oxidation promoter
21 should be neither too high 80 as to impart significant dehy-
22 drogenation activity to the catalyst during ca~alytlc `crack-
23 ing nor too low ~o promote adequate conversion of C0. to C2
24 during regeneration. The total catalyst composition of the
invention wlll, therefore, contain 2 to lO0, preferably 8
?6 to 50, p8rts per million (ppm) of the C0 oxidation promoter
27 component; 78 to 98, preferably 84 to 95, weight percênt o
28 the inorganic porous oxide matrix component; and 2 ~o 20,
29 pre~erably 5 to l5, weight percent of the crystalline alum-
$nosilicate zeolite component, based on the weight o the
31 total composition. Of particular interes~ i8 a catalytic
32 cracking compo8ition comprising 2 ~o lO0 ppm of metal or
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` :~LQ4~,484
1 compound of a metal selected from the group consisting of
2 platinum, palladium, iridium, rhenium or combinations there-
3 o~; O.l to L0 wt. % of alumina support material for said
4 metal or compound thereof; 78 to 98 wt. % of a silica-alumP
ina matrix binder; and 2 to 20 w~. % of a rare earth metal
6 ion and hydrogen ion exchanged zeolite Y, based on the weight
7 of the total composition. Preferably, ~he silica-alumina
8 matri2 will contain lO to 27 wt. % alumina and sufficient
9 hydrogen ion and/or rare earth metal ion will be exchanged
with the zeolite to produce a material having a ~odium level
of less than about 2 wt. % (as Na20)0
12 In the embodiment of the present invention`wherein
3 the ultra-stable faujasite or Y-type zeolite is used às the
4 inorganic porous oxide support for the C0 oxidation promoter
. . .
1~ the total catalyst composition wlll contain 2 to lOO,r pre-
16 erably 8 to 50, parts per mi~lion (ppm) of the C0 oxida~ion
1~ promoter component; 75 to 96, preferabl~ 82 to 95, wt. % o~
18 the inorganic porous oxide ma~rix component; and 4 to~259
: 19 preferably 5 to 18, wt. % zeolite where there is sufficient
.. .
C0 oxidation promoter-containing ultra-ætable Y-type~zeolite
21 and rare earth metal-containing zeolite so that the cataly~t
22 co~position will contain the aforesaid amount of C0 oxida-
23 tion promot~r and 0.8 to 4.5, preferably l.0 to 3.5,Y~wt. %
24 f rare earth metal (as oxides) or compound thereo*, all
based on the weight of the total composition. A typical
26 catalyæt conposition of this embodiment of the inven~ion
27 useful in catalytic cracking of petroleum feedstocks will
28 çomprise 0.5 to 5.0, preferably l.0 to 3.0, wt. % of the C0
29 oxidation promoter-containing ultra-stable Y~type zeolite
~ (where said zeolite contains 500 to 5000 ppm o~ the C0 oxl-
31 dation promoter~, 3.5 to 24.5, preferably 4.5 to 17.5, wt. %
.
32 Of the rare e~xth metal-containing X- or Y-type zeolite
. .
,
.
. .
.
~ ~6 ~ 8 ~
l (where said zeolite contains 14 to 22 wt. % of rare earth
2 metal on an RE203 basis) and 75 to 96 wt. % of a clay and/or
3 silica-alumina matrix material. Preferably, the matrix will
4 be the silica-alumina containing 10 to 27 wt. ~/0 alumina.
Particularly good cracking and carbon monoxide
6 conversion characteristics are exhibited by the catalyst
7 prepared in accordance with the present invention. The
8 catalyst of the invention is prepared by first supporting
4 the aforedescribed GO oxidation promoter on the aforedes-
cribed inorganic porous oxide, and thereafter embedding ~he
ll supported CO oxidation promoter and the aforedescribed crys-
12 talline aluminosilicate zeollte in the inorganic porous oxide,
13 most preferably silica-alumina or clay. Thus, the cataly~t
14 of the invention will comprise supported metal CO~oxidation
lS promoter particles and crystalline aluminosilicate particles
lG eimbedded in an inorganic porous oxide matrix.
l7 The supported CO oxida~ion promoter w~lch is incor-
18 porated into the catalyst composition is prepared by known
19 techniques such as~impregnation and vapor deposition. Pre-
2q ferably? the CO oxidation promoter is supported on an inor-
21 ganic porous oxide material by impregnation with a soIuticn
2~ of a compound of o~e or more of the aforementioned met~ls in
23 an amount sufficient to provide the desired concentration.
24 ~or example, an aqueous solutlon of palladium nitrate and/o~
chloroplatinic acid may be contacted with a porous inorganic
26 oxLde ~upport such as ~or example alumi~a or ultra-stable
27 Y-type zeolite, to produce a slurry which may thereafter be
28 filtered, drLed, c~lcined~ and/or pre-reduced with hydrogen
~ or other suitable reducing agents. The supported metal CO
oxidation promoter so produced will then preferably be pul-
31 verized to a partiçle size smaller than 10 microns diameter
32 size, preferably less than 1 micron diameter si2e. Option-
- 12 -
.
,
, ~,
10~i4~3~
1 ally, the support material may be pulverized before impreg-
2 nating with the metals.
3It is desirable to calcine the supported CO oxida-
4 tion promoter prior to its combination with the crystalline
aluminosilicate zeolite and matrix components. Such calcin-
6 a~ion tends to lock in the impregnated C0 oxidation promoter
7 on the porous oxide support. Accordingly, the C0 oxidation
- 8promoter supported on the porous oxide base is preferably
calcined in air at about 750-1250F. f3r several hours, e.g.
2-16 ~ours, prior to its combination with the zeolite and
1 matrix components. After calcina~ion, if desired, the 8Up-
12 ported CO oxidation promoter may be reduced with hydrogen at
13 700-1000F. or several hours in accordance with convéntional
14 practice. Alternately~ the supported C0 oxidation promoter
may also be reduced with hydrogen prior to calcination in
16 air and subsequent combination with the zeolite and ma~rix
17 components.
18The supported C0 oxidation promoter and crystal-
19 line aluminosilicate zeolite are thereafter embedded in the
i! 20 aforedeseribed inorganic porous oxide matrix. This may be
21 conveniently accomplished by dispersing the zeoli~e and the
22 supported metal C0 combustion promoter in a hydrogel of the
23 matrix material to produce a composite which is spray dried,
24 washed free of residual soluble salts and ~lash dried. For
examplç, rare earth e~c~anged zeolite Y par~icles (usually
26 less than about 5 microns) may be dispersed in impure silica-
27 alumina h~drogel or prewashed silica-alumina hydrogel-and
28 thereafter blended with p~rticles comprising the metar C0
2~ oxidation promoter supported upon a~ in~rganic porous oxide
3Q as described above to produc~ a composite which i8 thèresfter
31 spray dried, washed and flash dried. I de~ired, the finlsh-
32 ed catalyst may also be sulfided in a con~entional manner
- 13 -
104~
l prior to use. Other method~ Eor compositing the components
2 of the invention are known to those skilled in the art and
3 are meant to be included withLn the scope of this invention.
The feedstocks suit~ble for conversion in accor-
dance with the invention include any of the well known feeds
6 conventionally employed in hydrocarbon conversion processes.
7 Usually they will be petroleum derived, although other
8 sources such as shale oil, tar sands oil, and coal aré not
9 to be excluded. Typical of such feeds are heavy and ~ight
virgin gas oils, heavy and light virgin naphthas, solvent
ll extrac~ed g~s oils, coker gas oils, ~team-cracked gas oils,
12 cycle oils, deasphalted residua, etc.
13 For use in hydrocarbon conversion, the catalys~ of
14 the in~ention will be contacted wlth a hydrocarbon ~èèdstock
. .
l$ at a temperature in the range of about 500 to 1000F., a
l~ pressure of 0 to 50 psig, a feed rate of 0.1 to 10.0 ~lV/H~.
l7 In a prefèrred e~bodiment, the catalyst of the invention
18 will be employed for the catalytic cracking of a hydrocarbon
19 feedstock at a temperature in the range of about 875 to
;ii 2~ 1000~F., pressure of 0 to 25 psig and a feed rate of ~ to 50
21 V/V/Hr. ~he catalytic cracking catalyst composition of the
2~ invention may be regenerated at conditions whi~h include a
23 tempera~ure in the range of 1100 to 1400F., prefera~ly 1150
24 to 1325~.
The following examples further illustrate the
26 present inven~ion. Unless otherwise speci~ied, all percent-
~; 27 ageq and parts are by weight.
28 EXAMPLE 1
29 A catalyst of the invention was prepared as fol-
lowq: 1665 grams of a silica/alumina hydrogel (equivalçnt
31 to 151.3 gram of silica-alumina havislg an aIumina con~ent
32 of ~13 weight percent) were blended with 600 cc H20 and
. . .
.: .
.. .
, ,
10~6484
1 colloid milled. Separately, 22.5 grams of rare earth ex-
2 changed "Linde" zeolite Y (RE-Y) on a dry basis ~equivalent
3 to 17.0 grams as H-Y) were slurried in 250 cc H20 and to this
4 were added 0.67 grams of commercially available reforming
s catalyst sold under the trade ~ Cyanamid PHF-4. The
6 PHF-4 catalyst which comprises 0.3% P~ on an alumina support
7 had been pretreated with H2 at 925F. for 16 hours to re-
8 duce the Pt to el~mental form and then ground to pass a 200
9 mesh screen. The zeolite employed herein was prepared by
o sub~tantially completely exchanging the original a~kali
11 metal ions of ~he zeolite Y with a mi~ed rare ear~h chloride -~
12 solution (about 10 weight percent cerium, 55 weight percent
13 lanthanum, 20 weight percent neodymium, 10 weight percent
l4 p~eodymium), ~ilterin~, drying and calcining thè ma~erial
2 hours at 1000F., and then repeating the treatment two more
16 times. The zeolite after the flnal exchange con~ained 0.99
17 weight percent Na20 and 23.4 weight percent mixed rarè earth
18 oxides. The slurry of RE-Y and prereduced PHF-4 was adde~ ~o
19 the ~ilica/alumina hydrogel and homo~enized by colloid milling
twice. The composite was oven dried at 230F., groundL~nd
21 washed free of extraneous sal~s. The resulting catalyst was
2~ calcined in air at 1000F. It is designated "A" i~ s~bse-
23 q~ent examples and comprises about 12 ppm Pt, lOqo R~-~ and
24 90% sillca/alumina- ` `
EXAMPLE 2
26 Th~ example describss the preparation of anothe~
27 catalyst of the invention. I t was made in the manner of
28 ~xample 1 except the amount of prereduced PHF-4 wa~ i~creas-
29 ed. The catalyst of thl~ example is desi~ænated "B" and was
calcined in air a~ 1000F. It comprises about 30 ppm Pt,
31 10% RE-Y and 90% ~ilica-alumina.
- 15 -
1 ~6 ~ 4
1 EXAMPLE_3
2 This example describes the preparation o~ another
3 catalyst of the invention. ~e catalyst was made in the
4 manner of Example 1 except the PHF-4 cataly~t was replaced
with a composition comprising 0.3% Pt and 0.3% Ir on A1203,
6 The catalyst of this example is designa~ed "C" and was cal-
7 cined in air at 1000F. It oomprises about 12 ppm Pt, 12
8 ppm Ir, 10% RE-Y and 90% silica-alumina. ~'
~ EXkMPL~ 4
.
This example describes the preparati~n of another
c~alyst of the invention. It was made in the manner of
12 Example 1 except the PHF-4 catalyst wa~ replaced with a com- -
13 position comprising~0.3% Pt and 0.3% Re on A1203. This cata-
14 lyst is designated "D" and was calcined in air at 1000F.
It comprises about i2 ppm pt, 12 ppm ~e, 10% RE-Y and 90%
16 silica alumina.
17 EXAMPLE 5
18 The catalysts of ~his example are all c~alysts of
l9 the inventîon. They were made in s~milar fashion as cata-
20 lysts ~A", 19C~, and ~'D" except t~at the supported ~et~l CO
21 oxidation components were not prereduced with H2. Instead,
22 these metal C0 oxidat~on components were calcined in air at
23 1000F. prior to grinding and compositing with the RE-Y and
24 silica-alumina hydrogel. me composite catalysts were each
calcined at 1000F. in air. They are designated "E",~i"F'I,
26 and "G" and have the following compositions:
27Catalyst Compo~ition*
`;
28 E 10 ppm Pt/8.5% RE-Y/91.5% silica-alumina
29 F 101 ppim Pt-lO ppm Ir/8.5% RE-Y, 91.5% sLlica
31 G 10 ppm Pt-10 ppm Re/8.5% RE-Y/91.5% silica
32 alumina
33 ~ The noble metals are assumed to be present as oxides.
- 16 -
..~
~6 48 4
~XAMPLE 6
.....
2 Portions of Catalysts "A" through "G" were each
3 steamed at L400F. for 16 houræ at 0 psig and then used as
4 catalysts in a batch fluid bed reactor cracking a 500-700~F.
virgin gas oil at 950F. over a 2 minute cracking cyclç.
6 Thç results are summar~zed in the following table at a con-
7 stant 75% conversion for compariscn purposes.
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1 The data in Table 1 show that all of the catalysts,
2 "A" through "G", remain active and selectlv~ and do not"show
3 excessive amounts o~ coke, free hydrogen, and olefins with
4 the possible exception of cata'Lyst "G". The data show the
use of the metals in prereduced form as in catalysts "A"
6 through "D" show no ill effects of the noble metals in a
7 normal cracking operation~ Normal hydrogen yields with
8 catalysts having no noble metals present would yield about
9 25-35 SCF/B in the above test so it is seen that "A" through
"G" do not make excessive amounts of H2.
ll Catalysts "E", "F", and "G" show slightly lower
12 activity than catalysts "A" - "D" due to their lower RE-Y
13 c~ntents. In these catalysts the noble metals were pre- '
14 served in their'oxidized states (as oxides9 presumably~. '
Only catalyst 'IG'l shows a drop in activity with increases
: ~ .
16 in coke and H~ makes and a loss in naphtha yield, although ''
17 these changes in yield pattern are not considered exc~ssive
18 but merely directional. Normal equilibrium catalysts of
19 conventional types (without added noble metals) and compri-
sing several hundred ppm nickel and vanadium show hydrogen
21 yields of about 40~60 SCF/B H2. '~
. .
: 22 Exam~le 7
:~ .
,
' 23 Catslysts "Al' through "G" were sub;ected to a
: , . .
24 simNlated regenerator flue gas to demonstrate'their capabi- ''
2s lities or oxidizing CO to CO2. In the experiment, 10 grams
26 of the catalyst present as a ~luid bed was contacted with
27 N2 for 10 minutes at 1150F. to flush other gases from the
" 28 system and then the regenerator flue gas passed through the
:
' 29 system at a rate of 250 cc/minute for 8 minutes. At the end
'~ 30 o the period a sample of the exit gas was analyzed by mass
'~ 31 spectrograph for composition. Two se~s o experiments were
32 conducted: (a) with the fresh catalysts calcined at 1000F.
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10~6~84
l in air before testing, and (b) with the catalysts presteamed
2 at 1400F. for 16 hours and 0 psig. In the latter set the
3 possibility exists that the noble metals would agglomerate
4 in large crystals and thus be rendered ineffective as oxi-
dation catalysts. The simulated regenerator flue gas com-
6 prised air, CO, CO2, and added nitrogen. The amount of
7 oxygen (as air) was not sufficient to stoichiometrically
8 convert all of the CO to CO2. The results follow for each
9 set of experiments.
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1 The data in Table 2 show in all cases that the
: 2 ca~alysts are extremely effect:ive in converting CO to C2
3 and that with catalysts "C", "D", "E", and "F" the oxidation
4 was quantitative. This is particularly surprising when you
5 consider that as the 2 supply is depleted the reaction
6 still proceeds to completion with the noble metal level of
7 the composlte catalyst only in the 10-30 ppm range. The
8 cracking data demonstrate clearly that the catalysts are
9 highly active and selective, and do ~ot yield excessive ;~
10 amounts of coke and free hydrogen.
ll In another set of experiments, cat~ysts "A" `~
12 through "G" were each steamed at 140~F. for 16 hour~ and 0 ;
13 psig pressure. The catalys~swe~e then each charged ~o a
14 reactor at 1150~F., purged wi~h flow~ng n~trogen and then ,
15 subjected to flowing simulatqd rege~erator flue gas or.l0
16 minutes aS described above. Ihe r~ults follow~
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l The da~a in Table 3 show again,that the oxidation of CO to
2 C02 is effected essentially quantitatively. This demonstrates
3 that the steaming of the catalysts did not render the
4 noble metals to a non catalytic form. Hence the cracking
results with the steamed catalysts of the examples are made
6 valid by the fact that the noble metals in catalysts A
7 through G are still effective CO oxidation catalysts and do
8 not adversely effect the performance of the catalysts in
' 9 cracking operation.
; 10 The data,shown in the examples demonstrate that
11 the noble metal may be Pt alone or Pt/Ir and Pt/Re combina-
12 tions, all of which are extremely effective as catalysts
, 13 of this invention.
.
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1 EXAMPLE 8 ~ 0~6 ~8 4
2 A catalyst of the invention was prepared as follows:
3 1950 grams of ~ silica/alumina hydrogel (equivalent to about
4 177 grams of silica-alumina having an alumi~a content of 13
wt. %) were blended with 29.9 grams of rare earth exchanged
6 I'Linde" zeolite Y ~RE-Y) equivalen~ to 22.0 grams fau~a~ te
7 based on silica and alumina content. The RE-Y zeolite em-
a ployed herein was prepared as described i~ Exampl~ 1. To
9 the mixture of RE-Y and silica/alumina hydrogel was added
1.0 gram of a C0 oxidation ca~.~lyst component consisting of
ll about 20 wt. ~ alum~na and about 80 wt. % ultra-s~able zeo-
12 lite Y containing 0.5% Pt and 0.5% Pd by ion exchange ba~ed
13 on the ~otal weight of C0 oxidation catalyst component. The
14 ultra~stable zeolite Y was prepared by multiple exchanges
w~th ammonium ion solutions interspersed with caleinatio~
l6 at about 1000F. for 2 hour~. The composite was oven dried
17 ~ 230F., ground and washed free of ex~raneous sal~s. The
a resulting catalyst was cal~ined in air at 1000F. I~ is
19 designated "H" in subsequent examples and comprises `àbout .
0.5% of the C0 o~idation ca~alyst component, 11% RE-Y~,` and
21 88.5% silica/alumina matri~. The noble metal content of
22 the total composite catalyst "H" is about 25 ppm Pt and 25
23 ppm Pd.
24 EXAMPL2 9
Thi~ example describes the preparation of another
ca~yst of ~he inven~ion. It was made in the m~nner of
27 ExampLe 8 except the C0 oxidation catalyst component con- ;~
28 sisted o~ an ultra-stable zeolite Y containing 0.12% Na20
2~ and having an SiO2/A1203 mol ratio of 5.86. The ultra-
stable ~eoIite Y wa~ base exchanged with an aqueous 801u-
31 tion of Pd(~03)2 and H2PtCl~ to incorporate 0.5% Pt and 0~2~/o
32 Pd into the ultra-stable zeolit~. The catalyst of this
- 25 -
.. . :: .
1~4~84
1 example is designated "I" ~nd w~s calcined in alr at lOOO~F.
2 It contains 0.S% of ~he C0 oxidation catalyst component,
3 11% RE-Y and ~8.5% silica-alumina matrix. The noble metal
4 cQntent of the total catalyst composite is about 25 ppm Pt
s and 10 ppm Pd.
6 EXAMPLE 10
7 Por~ions of catalysts H and I after heating at
8 1000F. were examined for C0 oxidation of a simulated 1ue
9 gas. The gas wa~ passed through a bed of the catalyst at
lo 1150F. for 8 minutes after w~ich tlme the product gà's wa~
11 sampled and analyzed by mass spectrometry. The simulated
12 flue gas did not have a stoichiometric 2 content required
13 to eonvert all CO ~ Ç2 The results given beIow in Table
14 4 show that both catalysts H and I were effective for con-
verting CO ~o C0~. !
16 . TABL~ 4 . . .
.
17 Gas Feed Gas, ~ Y~ 5
18 ~oe~ E~ Mole? % Cat lYst H ~
.~ 19 2 3.48 0.07 0.02 -
. . .
C0 8.53 0.00 0.00
21 C02 12.00 20.1~ 20.05
22 N2 75.51 79.75 79.93
23 % CO Effçctively ~xidized 100 100 ~ .
24 ~XAMPLE 11
Portions of catalyst~ H and I were steamed at
' 26 1400F. for 16 hours and 0 psig. These catalysts were
27 evaluated for C0 oxidation in a manner simil~r to Example
28 10 above. The results are given beLow in Table 5.
: - 26 -
.
. .
4~
1 TABLE 5
2 Gas Feed Gas Flue Gas, Mole %
3 Components Mole % Ca
. _ . .
4 2 3.48 o.oo O 0O
CO 8.53 3.00 0.92*
6 C02 12.00 1'~.13 19.14
7 ~2 75.51 7~).87 79.94
8 % CO Effectively Oxidized 79~5 100
*Due to 2 deficienc in feed gas, about 1.57 mol % CO
should remain stoic~iometrically.
11 The data show that all of the oxygen was used up to effec-
12 tively oxidize all of the CO with catalyst I and about 80%
13 of it with catalyst H. This indicates that some of the noble
14 me~als i~ catalyst H may have been agglomerated by the steam
or interferred Wi~h by the alumina and thus rendered less
16 effective (25 ppm Pd in catalyst H vs. 10 ppm Pd in cata-
17 lyst I).
18 EXAMPLE 12
1~ Portions of H and I which had been steamed @1400F.
2Q for 16 hours at O psig were subjected to a fluidiæed bed
21 cracking operation at 950F. feeding a 500-700DF. virgin gas
22 oil over a 2 minute process period. The results are tabu-
23 l~ted below in Table 6 and axe correlated values at a con-
24 stant 75% con~erslon level twt. % 430F.-)-
TABLE 6
26 Catalyst Catalyst Reference
27 H I CatalYst
28 W/Hr/W(l) 11.5 10.7 10.3
29 Çarbon, Wt.% 2.3 2.4 1.9
C3-Gas, Wt. % 6.4 6.7 7~2
31 Total C4, Wt. % 9.7 9.8 10.5
32 Cs/430F., Wt. % 56.6 56.1 55.4
33 H2, SCF/B(2) 55 42 ,-~30
34 (1) Weight of feed processed per hour per weight of
~5 catalyst to give 75% conversion to carbo~ and
36 430F. product.
37 (2) Standard cubic feet per barrel of feed.
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1 Reference catalyst in the above table are averaged d~t~ for
2 a commercial zeolite catalyst of the same nominal composition
3 but which did not have any noble metals present. The data
4 show that notwithstanding the presence of Pt and Pd, there
is no debit in activity and in gasoline yields for the cata-
6 lysts of the invention.
7 EXAMPLE 13
8 Another ca~alyst of the invanti~n was prepared as
9 follows: 49.6 grams of the ultrs-stable zeolite Y (dry bas- ~- ;
10 is) of Example 9 was ion-exchanged first with 53 cc of an
11 aqueous solution of platinum ~etra-amine dichloride ~equiva-
12 lent to 0.25 gr Pt), dried at 250F. and then treated with
13 50 cc Pd(N03)2 solution tequivalent to O.lO gr Pd), d~ied
14 at 250F. and then calcined 3 hours at 1000F. The treatment
lS incorporated 0.5% Pt and 0.2% Pd into the ultra-stable 7-eo-
.
16 lite Y. In a separate blending vessel 1960 g. silica1alum-
17 ina (13% alumina) hydrogel was co~posited with the pre-ex-
18 changed precalcined RE-Y of Example 8 and with a portion of
19 the above noble metal exehanged ultra-stable zeolite Y. The
composite was dried and washed free of extraneous sol~ble
21 salts. The washed composite catalyst was oven dried at about
22 22SF. and calcined at 1000F. The catalyst, designated "J", ~:
23 comprised 10% RE-Y, 89% silica-alumina gel, 1% ultra-stable
. . .
24 zeolite ~, 50 ppm Pt and 20 ppm Pd. The noble metals are all
; 25 associated with the ultra-stable Y-type faujasite.
26 EXAMPLE l4
~ ..
27 The catalyst of this exsmple is al~o a catalyst of
28 the lnvention and was prepared by the procedure used as des-
` 29 cribed in Example 13. The composite catalyst was oven dried
.. 3~ at 225F. and calcined at lO00F. in air. The catalyst,
31 deslgnated "K'1, comprises 8P RE-Y faujasite, 89% silica- .
32 alumina gel, 3% ultra-stable Y ~aujasite, 50 ppm Pt and 20
- 28 -
,1 .
.. . . . . . .
~ 04~ ~ 4
1 ppm Pd. The noble metals are all associated with ~he ultra-
2 stable Y-type fau;asite.
3 EXAMPLE 15
.. . .
4 The catalyst of this example is not a catalyst of
S this invention. A commercial catalyst comprising about 8.5%
6 RE-Y faujasite and a~out 91~5~o silica-alumina gel was im-
- 7 pregnated with dilu~ed platin~m ~etra-amine dichloride solu-
~ 8 tion, left to soak at ambient temperatures for 4 hours and
i .
9 then oven dried. It was then calcined at 1000F. for 6
hours in air. m e catalyst, designated "L", comRrised 50
11 ppm Pt.
` 1~ EXAMPLE 16
.
13 Catalyst "J", "K" and "L" were each steamed at
14 1400F. for 16 hours and 0 psig and examined for C0 oxida-
tion of a simulated flue gas as described in Example 10
1~ above. The results are presented in Table 7 below.
17 The feed gas for catalyst l'Li' was of slightly
18 different cQmpoSition than that used for catalysts "J" and
19 "K".
'
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The data show that all three catalysts were very effective in pro-
moting the oxidation of Co to CO2, with catalysts "J" and "K" of
the invention showing esentially quantitative utilization of oxygen
in the process period.
EXA~IPLE 17
Catalysts "J", "K", and-"L" were-evaluated for cracking
properties under the same conditions as described in Example 12.
- The catalysts were steamed at 1400F. before testing. The results
; are shown below in Table 8 and are correlated values at a constant
75% conversion level.
TABLE 8
Catalyst J K L References
% RE-Y 10 88.5 11
% Ultra-stable-Y 1 3 0 0
Pt, ppm 50 50 50 0
Pd, ppm 20 20 0 0
` ~t 75% Conversion
W/Hr./W 12.8 10.87O7 10.3
Carbon, Wt. %2.7 2.94.2 1.9
C3- Gas, Wt. %6.6 7.49.1 7.2
1~ Total C4, ~1t. % 9.610.5 11.9 ln.5
Cs/430F., Wt.:%56.1 54.249.8 55.4
H2, SCF/B 62 71107 ~J30
The data show that the catalysts of the invention, "J" and "K" are
more active and just as selective to naphtha as the reference cata-
lyst, even though "J" and "K" have lower RE-Y contents. There is a -~
small increase in coke and hydrogen makes noted for "J" and "K" rela-
tive to the reference catalyst due to the 70 ppm total noble metals
on these catalysts, a level which probably is higher than necessary
to effectively promote CO oxidation as shown in Tables 4 and 5 above.
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Comparing "K" and "L" which are at about the same RE-Y content,
: the performance of "K" of the invention is much superior in both
product selectivity and :
.
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1 in activity. Here the increased coke and hydrogen makes
2 and decreases CsY430F. yields in addition to severely
3 lower activity for "L" show that impregnation of the com-
4 posite catalyst with noble metal i5 not a particularly de-
sired way to incorporate the oxidation promoter into the
6 catalyst.
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