Process for preparing multimetallic reforming catalysts

A process for the synthesis of catalysts by pre-forming a porous refractory inorganic oxide support, or carrier from a coarse particulate solid, preferably an alumina extrudate, contacting said preformed support with an acid solution, and then treating, contacting and neutralizing said preformed acid treated support with a base prior to the impregnation of said neutralized support with a metal, or metals, hydrogenation-dehyrdogenation component. The preformed solid support ranges at least about 1/32 inch diameter, and preferably at least about 1/16 inch diameter, and larger.

BACKGROUND OF THE INVENTION AND PRIOR ART 
Catalytic reforming, or hydroforming, is a process well known to the 
petroleum refining industry for improving the octane quality of naphthas 
and straight run gasolines. In a typical process, a series of reactors are 
provided with fixed beds of catalyst which receive upflow or downflow 
feed, and each reactor is provided with a heater, or interstage heater, 
because the reactions which take place are endothermic. A naphtha feed, 
with hydrogen, or recycle gas, is co-currently passed sequentially through 
a reheat furnace and then to the next reactor of the series. The vapor 
effluent from the last reactor of the series is a gas rich in hydrogen, 
which usually contains small amounts of normally gaseous hydrocarbons, 
from which hydrogen is separated from the C.sub.5.sup.+ liquid product and 
recycled to the process to minimize coke production; coke invariably 
forming and depositing on the catalyst during the reaction. 
Reforming catalysts are recognized as dual functional, the catalyst 
composite including an acidic component providing an isomerization 
function, and a metal, or metals, or a compound or compounds thereof, 
providing a hydrogenation-dehydrogenation (hydrogen transfer) function. 
Halogen, e.g., chlorine, is generally added to provide the required acid 
function. The platinum group metals (ruthenium, osmium, rhodium, iridium, 
palladium and platinum), particularly platinum, have been widely used in 
commercial reforming operations to provide the 
hydrogenation-dehydrogenation function, these metals being composited with 
an inorganic oxide base, particularly alumina; and in recent years 
promoters such as iridium, rhenium, germanium, tin, etc., have been added, 
particularly to platinum, to enhance one or more of certain of the 
characteristics which a good reforming catalyst must possess--viz., 
activity, selectivity, activity maintenance and yield stability. 
The principal reactions produced in reforming are dehydrogenation of 
naphthenes to produce the corresponding aromatic hydrocarbons; 
isomerization of n-paraffins to form branched-chain paraffins and 
isomerization of ring compounds, and dehydrogenation of the latter to form 
aromatics; dehydrocyclization of paraffins to form aromatics; and 
hydrocracking of high molecular weight feed constituents to form lower 
molecular weight, or lower boiling, constituents. The net effect of these 
reactions is to increase the concentration of aromatics and isomers, with 
consequent octane improvement of naphthas boiling within the gasoline 
range. Hydrogenolysis, a specific and severe form of hydrocracking which 
produces methane, can also occur; and hydrogenolysis is particularly acute 
in reforming with some promoted platinum catalysts, or new generation bi- 
or multi-metallic reforming catalysts. 
Methods for the preparation of reforming catalysts too are well known. 
Typically, an alumina or alumina-containing extrudate is prepared by 
passing an extrudable mixture of alumina and water through orifices of 
desired diameter within the die plate of an extruder, the extrudate 
therefrom then being broken or cut into segments of desired length. The 
extrudate supports are dried, calcined and then contacted with a 
salt-containing solution, or solutions, and impregnated with sufficient of 
the salt, or salts, to provide the desired amount of the metal, or metals, 
hydrogenation-dehydrogenation component. Impregnation aids such as 
aluminum nitrate or carbon dioxide may be added to the impregnating 
solution, or solutions, to promote dispersion and distribution of the 
catalytic metal, or metals, upon the surface of the catalyst. The catalyst 
is finished by various additional steps such as washing, drying, calcining 
and other procedures prior to its use in reforming. The halide is 
generally added simultaneously with the metal, or metals, 
hydrogenation-dehydrogenation component. 
Whereas these types of processes, and catalysts, have performed well it is 
nonetheless especially desirable to provide new and improved processes, 
and catalysts, which are capable of achieving higher activities, with 
satisfactory stability. 
It is accordingly a primary objective of the present invention to provide a 
new and improved process for the preparation of such catalysts for use in 
upgrading naphthas by reforming them to produce higher octane gasolines. 
More specifically, it is an objective to provide a new and improved process 
for the production of catalysts which, when used at suitable reforming 
conditions, are more highly active in the production of high octane 
gasolines, while yet maintaining good selectivity, activity maintenance 
and yield stability. 
These objects and others are achieved in accordance with the present 
invention embodying a process for the synthesis of reforming catalysts by 
pre-forming a porous refractory inorganic oxide support, or carrier from a 
coarse particulate solid, preferably an alumina extrudate, contacting said 
preformed support with an acid solution, and then treating, contacting and 
neutralizing said preformed acid treated support with a base prior to the 
impregnation of said neutralized support with a metal, or metals, 
hydrogenation-dehydrogenation component. The preformed solid support 
ranges at least about 1/32 inch diameter, and preferably at least about 
1/16 inch diameter, and higher. 
Surprisingly, it has been found that the sequence of acid treating a solid, 
porous refractory inorganic oxide support with subsequent neutralization 
of the acid-treated support prior to the addition of a metal, or metals 
hydrogenation-dehydrogenation component to the support results in the 
formation of more highly active catalysts. It is essential that the 
support be preformed, and that the preformed support be treated prior to 
metals impregnation by contact with an acid solution, preferably a halogen 
acid solution, without dissolving any significant portion of said support. 
Thereafter the acid treated, preformed support is neutralized by contact 
with a base, preferably a weakly basic solution, e.g., an ammonium 
hydroxide solution; again, without dissolving any significant portion of 
said support. Suitably, the neutralized preformed support is then 
impregnated with the desired hydrogenation-dehydrogenation component, 
e.g., by the addition of a metal from a single solution, or by the 
addition of more than one metal, e.g., either by simultaneous impregnation 
from a single solution or by sequential impregnation from several 
solutions to which different metals have been added. The catalyst 
thereafter is washed, dried, calcined or otherwise treated in conventional 
manner. The catalyst so produced is far superior, and consistently 
superior, to one prepared by a similar impregnation of the support with a 
given metal, or metals, except that the support was not neutralized by 
contact with a base after acidification. Whereas there is no desire to be 
bound by a specific theory of mechanism, it is believed that the acid 
treatment with subsequent neutralization provides an "activated" surface, 
or surface more amenable to the more efficient dispersion and distribution 
of the metal, or metals, hydrogenation-dehydrogenation components. It is 
also believed that this treatment changes the acid strength distribution 
of the support providing a surface with an improved cracking character. 
The support is constituted of a porous refractory inorganic oxide, 
particularly alumina, or alumina containing portions of other well known 
refractory inorganic oxides such as silica, zirconia, magnesia, etc. in 
the form of pills, pellets, beads, extrudates, or sieved particulate 
support materials. Preferred supports have an apparent bulk density of 
about 0.3 to about 0.8 g/cc and surface area characteristics such that the 
average pore diameter is about 20 to 300 Angstroms, the pore volume ranges 
about 0.1 to about 1 cc/g and the surface area ranges about 100 to about 
400 m.sup.2 /g. In general, best results are obtained with a gamma-alumina 
support material which is used in the form of extrudate particles having 
an average diameter equal to or greater than 1/32 inch, preferably about 
1/16 inch, an apparent bulk density of about 0.3 to about 0.8 g/cc., a 
pore volume of about 0.4 ml/g., and a surface area of about 150 to about 
250 m.sup.2 /g. 
The preferred alumina support material may be prepared in any suitable 
manner and may be synthetically prepared or natural occurring, preferably 
the former. Whatever type of alumina is employed, it may be activated 
prior to use by one or more treatments including drying, calcination, 
steaming, etc., and it may be in a form known as activated alumina, 
activated alumina of commerce, porous alumina, alumina gel, etc. For 
example, the alumina support may be prepared by adding a suitable alkaline 
reagent, such as ammonium hydroxide, to a salt of aluminum such as 
aluminum chloride, aluminum nitrate, aluminum alkoxide, aluminum sulfate, 
etc., in an amount to form an aluminum hydroxide gel which upon drying and 
calcining is converted to alumina. The alumina support may also be 
prepared by precipitation of sodium aluminate alone or combined with other 
aluminum salts. The alumina supports so prepared may or may not contain 
sodium and/or sulfate impurities. 
The calcined alumina extrudates are soaked in an acid solution. Suitable 
acids include inorganic acids, exemplary of which are nitric acid, 
phosphoric acid, hydrochloric acid, hydrobromic acid and the like. 
Hydrochloric and nitric acids are preferred. The acid may range in 
strength from about 0.1-15.6 N; 1-5 N being preferred and 1 N being most 
preferred. The soaking period may range from about 1 to about 24 hours, 
from about 10 to about 20 hours being generally preferred. Generally, 
ambient conditions are employed. 
Exposing the alumina to a halogen acid, e.g., hydrochloric acid, introduces 
high levels of chloride into the alumina base. This high chloride content 
inhibits subsequent metals impregnation, and the finished catalyst gives 
high acid cracking in naphtha reforming. Chloride is effectively removed 
from the acid treated alumina by the subsequent neutralization. Similarly, 
residual nitric acid on the surface of the support also inhibits the 
impregnation of the metals. For this reason nitric acid treatment of the 
support must also be followed by neutralization. 
After the acid treatment, the support is usually washed to remove the 
excess acid. Thereafter, the support is contacted with, or immersed in a 
basic solution of normality ranging from about 0.1 N to about 15 N, 
preferably from about 0.1 N to about 5 N. The contact, or soak period can 
range from about 0.1 hour to about 24 hours, preferably from about 1 hour 
to about 5 hours. One hour is generally sufficient, and is most preferred. 
Exemplary of the bases which can be employed are ammonium hydroxide, 
organic amines, quaternary ammonium bases and the like. Inorganic 
hydroxides, carbonates and other bases are less suitable due to the 
contamination of the alumina by the metal ions, these depressing the 
activity of the finished catalyst. Aqueous solutions of organic amines and 
quaternary ammonium bases are also less suitable because of the 
possibility of nitrogen poisoning the alumina. Ammonium hydroxide is most 
preferred, and preferably the support is contacted with ammonium hydroxide 
by soaking at ambient conditions for the desired time. The strength of the 
ammonium hydroxide solution ranges from 0.1-15 N; a range of 0.1-5 N being 
preferred; 0.5-1.0 N being most preferred. A soaking period ranging from 
5-60 min. is generally adequate, 60 min. being preferred. 
In preparation of the catalyst, the neutralized inorganic oxide support, in 
dry or solvated state, is next contacted, with a solution which contains a 
compound or salt, or compounds or salts, of the desired catalytic metal, 
or metals, and thereby impregnated by absorption from a dilute or 
concentrated solution to effect uptake of the metal component, or 
components, with subsequent filtration or evaporation. The metal, or 
metals, is contained in the solution in the form of any of the common 
inorganic or organic salts of the elemental metal. These include the 
halides, nitrates, nitrites, sulfates, sulfites, carbonates, hydroxides, 
bicarbonates or carboxylates, preferably the fluorides, chlorides, 
nitrates, nitrites, and hydroxides; and including the oxides. The more 
preferred salts are the fluorides, chlorides, and nitrates due to their 
availability, low cost, and ready solubility in aqueous media. 
The preferred catalyst is one which contains a platinum component, 
generally in concentration ranging from about 0.1 percent to about 2 
percent, preferably from about 0.2 percent to about 0.6 percent, based on 
the weight of the catalyst (dry basis). The preferred catalyst generally 
also contains a promoter metal, preferably iridium or rhenium, generally 
in concentration ranging from about 0.1 percent to about 2 percent, 
preferably from about 0.2 percent to about 0.6 percent, based on the 
weight of the catalyst (dry basis). Preferably, the platinum and promoter 
metal are employed in weight ratios of platinum:promoter metal ranging 
from about 0.25:1 to about 3:1, more preferably from about 0.75:1 to about 
1.25:1; and most preferably is employed in substantially equal weight 
ratios when the total content of these metals ranges from about 0.4 
percent to about 1 percent, based on the total weight of the catalyst (dry 
basis). The halogen content of the catalyst generally ranges from about 
0.1 to about 2.5 percent, preferably from about 0.7 to about 1.2 percent, 
based on the weight of the catalyst (dry basis). 
Copper can also be incorporated with the support in small and critical 
concentrations by impregnation from a halogen acid solution as disclosed 
in U.S. Ser. No. 53,374, filed June 29, 1979; hereby incorporated by 
reference. Suitably, a sufficient amount of a copper-containing compound 
is impregnated into the support to provide from about 0.01 to about 0.1 
percent copper, preferably from about 0.025 to about 0.08 percent copper, 
based on the weight of the catalyst (dry basis). A preferred catalyst is 
one which, besides copper, contains platinum and rhenium in specified 
concentrations. The copper is composited in amount sufficient to provide a 
molar ratio of copper:(platinum plus rhenium) ranging from about 0.02:1 to 
about 0.25:1, preferably from about 0.04:1 to about 0.20:1. The exact 
concentration of the copper depends to some extent on the nature of the 
feedstock and reforming conditions, but it is important that the 
concentration of copper on the catalyst be controlled to the proper level. 
High concentration of copper acts as a poison and depresses catalyst 
activity. 
While the catalyst may be used directly, it is preferred that it be 
sulfided to achieve the ultimate suppression of hydrocracking during 
reforming. Sulfur eliminates principally the formation of excessive 
methane, and copper eliminates principally the formation of the 
C.sub.2.sup.+ hydrocarbon gases. Together, a given amount of both copper 
and sulfur prove superior in the suppression of total hydrocracking than a 
corresponding amount of either copper or sulfur employed individually. The 
sulfur content of the catalyst generally ranges to about 0.2 percent, 
preferably from about 0.05 percent to about 0.1 percent, based on the 
weight of the catalyst (dry basis). The sulfur can be added to the 
catalyst by conventional methods, suitably by breakthrough sulfiding of a 
bed of the catalyst with a sulfur-containing gaseous stream, e.g., 
hydrogen sulfide in hydrogen, performed at temperatures ranging from about 
350.degree. F. to about 1050.degree. F. at pressures ranging about 1-40 
atmospheres for the time necessary to achieve breakthrough, or the desired 
sulfur level. 
Impregnation of the metals is accomplished by any conventional means. Both 
the incipient wetness technique and soaking in an excess of the 
impregnation medium are acceptable. The impregnation of the metal 
components into a support is carried out by impregnating the support with 
a solution, or solutions, of the respective salts or compounds of the 
elements or metals to be incorporated. Salts, acids or compounds of each 
metal can be dissolved in a solution, or the salts, acids or compounds can 
be separately dissolved in solutions, the solutions admixed, and the 
admixed solution used for impregnation of the carrier. One metal can be 
added initially using conventional techniques, and then another metal, or 
metals, can be added simultaneously or sequentially, suitably by 
impregnation. The amount of impregnation solution used should be 
sufficient to completely immerse the carrier, usually within the range 
from about 1 to 20 times that of the carrier by volume, depending on the 
metal concentration in the impregnation solution. The impregnation 
treatment can be carried out under a wide range of conditions including 
ambient or elevated temperatures and atmospheric or superatmospheric 
pressures. 
The catalyst, after impregnation, is dried by heating at a temperature 
above about 80.degree. F., preferably between about 150.degree. F. and 
300.degree. F., in the presence of nitrogen or oxygen, or both, in an air 
stream or under vacuum. The catalyst is calcined at a temperature between 
about 500.degree. F. to 1200.degree. F., preferably about 500.degree. F. 
to 1000.degree. F., either in the presence of oxygen in an air stream or 
in the presence of an inert gas such as N.sub.2. 
The catalyst can be activated by contact with air at temperatures ranging 
from about 500.degree. F. to about 1050.degree. F. for periods ranging 
from about 1 to about 24 hours in either flowing or static air. Reduction 
is performed by contact with flowing hydrogen at temperatures ranging from 
about 350.degree. F. to about 1050.degree. F. for periods ranging from 
about 0.5 to about 24 hours at about 1-40 atm. The catalyst can be 
sulfided by use of a blend of H.sub.2 S/H.sub.2 and performed at 
temperatures ranging from about 350.degree. F. to about 1050.degree. F. at 
about 1-40 atm. for a time necessary to achieve breakthrough, or the 
desired sulfur level. Post-sulfiding and stripping can be employed if 
desired at conditions similar to those for reduction of the catalyst. 
Treatment of the catalyst with a mixture of chlorine and oxygen can be 
substituted for air activation if desired. This procedure can correct for 
any possible maldispersion of the metals arising from improper 
impregnation, and the procedure is useful in restoring activity during 
regeneration-rejuvenation after on oil service. A blend of chlorine, 
oxygen and nitrogen can also be employed at temperatures ranging from 
about 350.degree. F. to about 1050.degree. F. for periods ranging from 
about 1 to about 24 hours at 1-40 atm. Treat times for these various 
operations is a function of gas flow rates, gas compositions, and 
conditions. The catalyst halide content can be controlled during 
impregnation, or adjusted by treatment with water or water-hydrogen 
chloride blends. 
This catalyst can be used in semi-regenerative, cyclic, semi-cyclic, or 
continuous bed reforming. The catalyst is particularly useful at severe 
reforming conditions, especially at low pressures, or pressures ranging 
from about 50 psig to about 150 psig, where maximum yield is favored. 
The feed or charge stock can be a virgin naphtha, cracked naphtha, a 
Fischer-Tropsch naphtha, or the like. Typical feeds are those hydrocarbons 
containing from about 5 to 12 carbon atoms, or more preferably from about 
6 to about 9 carbon atoms. Naphthas, or petroleum fractions boiling within 
the range of from about 80.degree. F. to about 450.degree. F., and 
preferably from about 125.degree. F. to about 375.degree. F., contain 
hydrocarbons of carbon numbers within these ranges. Typical fractions thus 
usually contain from about 20 to about 80 Vol. % paraffins, both normal 
and branched, which fall in the range of about C.sub.5 to C.sub.12, from 
about 10 to 80 Vol. % of naphthenes falling within the range of from about 
C.sub.6 to C.sub.12, and from 5 through 20 Vol. % of the desirable 
aromatics falling within the range of from about C.sub.6 to C.sub.12. 
The reforming runs are initiated by adjusting the hydrogen and feed rates, 
and the temperature and pressure to operating conditions. The run is 
continued at optimum reforming conditions by adjustment of the major 
process variables, within the ranges described below: 
______________________________________ 
Major Operating 
Typical Process 
Preferred Process 
Variables Conditions Conditions 
______________________________________ 
Pressure, Psig 50-750 100-300 
Reactor Temp., .degree.F. 
750-1100 850-1000 
Gas Rate, SCF/B 
1500-10,000 
2000-7000 
(Incl. Recycle Gas) 
Feed Rate, W/W/Hr 
0.5-10 1-3 
______________________________________ 
The invention will be more fully understood by reference to the following 
demonstrations and examples which present comparative data illustrating 
its more salient features. All parts are given in terms of weight except 
as otherwise specified.

EXAMPLES 
A series of catalysts were prepared from commercially supplied 1/16" high 
purity gamma alumina extrudates calcined in air at 1000.degree. F. for 3 
hours prior to use. 
Catalyst A 
To a solution of 37.5 ml of concentrated hydrochloric acid and 412.5 ml of 
water was added 291 g. of 1/16 inch alumina extrudates. After 20 hrs. the 
extrudates were recovered by filtration and washed with two liters of 
water to remove the hydrochloric acid. The extrudates were added to a 
solution of 33 ml of concentrated ammonium hydroxide and 417 ml of water. 
After 1 hr. the extrudates were recovered by filtration and washed with 
eight liters of water to remove ammonium hydroxide. In a two liter fritted 
glass filter funnel was placed 450 ml of water. Carbon dioxide was bubbled 
up through the frit for 30 min. The extrudates were added to the water, 
and the mixture was treated with carbon dioxide for 30 min. An aqueous 
solution (70 ml) containing 2.101 g. of PdCl.sub.4, 1.215 g. of 
HReO.sub.4, 0.210 g. of H.sub.2 PtCl.sub.6, and 3 g. of HCl was added with 
stirring, and carbon dioxide was bubbled through the mixture for 4 hrs. 
The aqueous phase was removed by decantation, and the catalyst was dried 
in a vacuum oven at 266.degree. F. for 24 hrs. The catalyst was calcined 
in a muffle furnace at 1000.degree. F. for 3 hrs. The catalyst was ground 
to a particle size of 14-35 mesh. A 25 g. sample was placed in a quartz 
reactor and was treated at 932.degree. F. with the following gases at a 
uniform flow rate of 600 cc/min: H.sub.2, 1 hr.; 0.2% H.sub.2 S in 
H.sub.2, 7 min.; H.sub.2, 2 hrs. The composition of the catalyst is given 
in Table I. 
Catalyst B 
This catalyst was prepared in the same manner as Catalyst A except the 
alumina extrudates were not treated with hydrochloric acid and ammonium 
hydroxide prior to impregnation. The composition of the catalyst is given 
in Table I. 
Catalyst C 
A Pt-Re catalyst was prepared using the procedure described for Catalyst A, 
the procedure of this invention. The composition of the catalyst is given 
in Table I. 
Catalyst D 
A Pt-Re catalyst was prepared using the procedure described for Catalyst B. 
The composition of the catalyst is given in Table I. 
Catalyst E 
A Pt-Re catalyst was prepared using the procedure described for Catalyst A, 
the procedure of this invention, except 30 ml. of concentrated nitric acid 
and 420 ml. of water were used to treat 291 g. of extrudate. The 
composition of the catalyst is given in Table I. 
TABLE I 
______________________________________ 
Components Cat A Cat B Cat C Cat D Cat E 
______________________________________ 
Platinum 0.11 0.098 0.3 0.3 0.3 
Rhenium 0.26 0.21 0.3 0.3 0.3 
Palladium 0.29 0.31 -- -- -- 
Chlorine 0.86 0.86 0.90 0.9 0.8 
Sulfur 0.085 0.056 0.053 0.08 0.10 
______________________________________ 
Catalyst A and B were each then contacted at reforming conditions in 
separate runs with heptane and naphtha feeds, respectively, the 
inspections on the petroleum naphtha being given in Table II. 
TABLE II 
______________________________________ 
ASTM Distillation, .degree.F. 
Initial 145 
10 181 
20 204 
30 222 
40 240 
50 258 
60 275 
70 293 
80 313 
90 334 
Final B.P. 363 
Octane No. RON Clear 34.8 
Gravity, .degree.API 59.7 
Sulfur, Wt. ppm &lt;0.1 
Water, Wt. ppm &lt;10 
Chloride, Wt. ppm &lt;0.1 
Analysis, Vol. Percent 
Paraffins 69.4 
Naphthenes 16.7 
Aromatics 13.9 
______________________________________ 
The results of the reforming runs are given in Tables III-A and III-B, 
respectively. 
TABLE III-A 
______________________________________ 
Heptane Reforming 
1 Atm., 500.degree. C., 2.5 W/H/W, H.sub.2 /Heptane 37/1 
Selectivity, wt. % 
Catalyst 
Conversion, % 
C.sub.6.sup.- 
Iso--C.sub.7 
Benzene 
Toluene 
______________________________________ 
A 77.3 13.9 4.0 0.9 81.2 
B 70.2 23.0 6.3 2.2 68.5 
______________________________________ 
The activity of Catalyst A, the catalyst made pursuant to this invention, 
as measured by conversion, was far greater than the activity of Catalyst 
B. Selectivity was also greatly improved by the process of this invention. 
Thus, Catalyst A gave a product of greater aromatic content than did 
Catalyst B. Catalyst A thus gave a 63.5% yield of aromatics vs. a yield of 
49.6% for Catalyst B. 
Both catalysts were evaluated for naphtha reforming; the results are shown 
below. The activity and yield credits for Catalyst A, observed in heptane 
reforming, are equally apparent in naphtha reforming. 
TABLE III-B 
______________________________________ 
Reforming of Low Sulfur Fos Paraffinic Feed 
With Pd/Re/Pt 
Relative Activity 
C.sub.5.sup.30 LV% 
Catalyst (400 hr.) @ 100 RON (4000 Hr.) 
______________________________________ 
A 1.5 71.6 
B 1.0 63.3 
______________________________________ 
Catalyst A prepared by the procedure of this invention is clearly the 
superior catalyst. 
Catalyst C and D were evaluated in heptane reforming, with the results 
given in Table IV. 
TABLE IV 
______________________________________ 
Heptane Reforming 
500.degree. C., 100 psig, 10 W/H/W, H.sub.2 /Heptane = 5 
Catalyst C.sub.5.sup.+ Yield, % 
Toluene Yield, % 
______________________________________ 
C 79.7 34.1 
D 77.5 26.0 
______________________________________ 
Catalyst C prepared by the procedure of this invention is obviously 
superior in activity and yield to Catalyst D. 
Catalyst D and E were evaluated in heptane reforming with the results given 
in Table V. 
TABLE V 
______________________________________ 
Heptane Reforming 
500.degree. C. 100 psig, 10 W/H/W, H.sub.2 /Heptane = 5 
Catalyst C.sub.5.sup.+ Yeild, % 
Toluene Yield, % 
______________________________________ 
D 77.5 26.0 
E 78.5 29.0 
______________________________________ 
Catalyst E, prepared by the procedure of this invention, is superior in 
activity and yield to Catalyst D. 
It is apparent that various modifications and changes can be made without 
departing from the spirit and scope of the present invention.