Title of Invention

A METAL IONIC CATALYST COMPOSITION AND A PROCESS THEREOF

Abstract The present invention relates to a metal ionic catalyst composition for the catalytic conversion of industrial pollutants and the process of preparation of the same. The present invention also relates to a process of coating of the said catalyst composition on a cordierite honeycomb.
Full Text

Field of the Invention
The present invention relates to a nanosized active catalyst comprising noble-metal ions
catalytic conversion of auto exhaust gases including CO oxidation, NO reduction, 'HC
oxidation and a process of preparing the same. The present invention also relates to the
process of coating of nanosized active catalyst on a honeycomb made of cordierite
ceramic.
Background of the invention
Cordierite honeycomb is used for preparation of catalytic converters, which are used for the treatment of industrial pollutants e.g. exhaust pollutants. The monoliths are coated with the active metal catalysts by various processes. Cordierite honeycomb monolith is generally first wash coated with y- AI2O3. Most recent method of coating y-AI2O3 is by sol-gel method. Jiang P., Lu G., Guo Y., Quo Yang., Zhang S. and WangX. Surf.& Coat. Tech. 190(2005) 314-320, recently have studied the wash coat properties of y- AI2O3 prepared by sol-gel method.
Cordierite dipped in Aloha (pseudo-boehmite) mixed with urea and 0.3M nitric acid in 2:1:5. Sol is claimed at 450V producing y- AI2O3 coating, Duiesterwinkel, A.E. Clean Coal Combustion with In-Situ Impregnated Sol-Gel Sorbent. Ph.D. Thesis, Delft University of Technology, Delft, 1991.
After washcoating of y-Al203 active phase is coated onto it. Well-optimized methods already exist for the preparation of various powder catalysts. These catalysts can simply be coated on a monolith support using slurry made of the same catalysts. The method is called slurry coating method.
For coating a catalyst using slurry method, Adding, W.P.; Lachman, L.M.; Patel, M.D.; Williams, J.L.; Zion, K.E. High Surface Area Wash coated Substrate and Method for producing Same. U.S. Patent 5, 212, 130, 1993 (assigned to Corning Inc.), a number of components are needed; a solvent, properly sized catalyst particles, the binder and, optionally a surfactant and a temporary binder. All components of the coating slurry should be well mixed using a high-shear mixer until the slurry is homogeneous. A dried monolith is dipped in this slurry for a short period (few seconds). Thereafter drying is done horizontally while rotating the monolith continuously. Finally calcinations is done typically at 400-900’C depending upon the catalyst to be coated. In a recent study by Tagliaferri, S., Coppell, Rene A., Baker, A., ApplCatal.B: Environment, 15, 159-177,

(1998). Behaviour of the different types of catalyst has been investigated. Compositions of various catalysts are: Pd/ , Pd-Rh/AbOs, Pd/Ce/AbOa, Pd-Rh/Ce/AbOs. In the hand book of heterogeneous catalysis Hand Book of Heterogeneous Catalysis, Editors; G. Ertl, H. KnOzinger and J. Weitkamp. Publisher; Wiley-Vhh, vol.4,1591-1594 (1997). Reactions over coated honeycomb have been demonstrated. Conversion temperatures are fairly high and in the range of 300-400’C. Prior Art
In the aforementioned patent citation it is evident that it describes a well known impregnation method in which support and catalytically active component are taken separately. After the calcinations the metal component is dispersed over support in the form of a metal.
Further, it is also evident from the above citations that they utilize high surface area refractive oxide such as activated alumina is taken and to that metal component in the form of an aqueous solution is added. Solution is made acidic by adding some acid like nitric acid. pH is maintained 2-2.5.
Furthermore, the above citations make use of Promoters, which are rare earth materials along with binder (zirconia). The whole mixture is ball milled to get slurry or a known particle size. This slurry is claimed to get a catalyst where metal is impregnated over the support Or the same slurry can be sprayed to a monolith carrier followed by the calcinations to get a monolith coated with the same catalyst. If desirable, oxygen storage component such as cerium dioxide can also be added to the slurry. The activated alumina should be dry enough to absorb all the aqueous solution of active metal component. To stabilize the high surface area metal oxide, a stabilizer such as lanthanum nitrate can be added.
Thus, it is evident from the prior art that all the specified compositions utilize various additives like binders, promoters and stabilizers. However, the instant invention is distinct as it does not utilize any of the additives as mentioned. In addition, it is also evident from the prior art that all the citations do utilize high processing temperatures to bring about the conversion of effluents. However, the instant invention was successfully able to arrive at low processing temperatures for conversion of the effluents.
Therefore, the instant invention is both novel and inventive. It is novel at it is able to arrive a t a catalyst composition which is achieved by dispersing the metal in the form

of ions on the support. It is inventive as it is able to arrive at low full conversion temperature for conversion of effluents. Drawbacks of the prior art:
a) Numbers of precursors are more as we have to use binders (temporary and
permanent) and surfactant. Binder decreases the activity of the catalyst.
b) Adhesion between catalyst and the cordierite surface is poor.
Object of the present invention:
The principal object of the present invention is to develop a metal ionic catalyst
composition.
Another object of the present invention is to develop a process for the preparation of
metal ionic catalyst composition.
Yet another object of the present invention is to develop a method of coating the metal
ionic catalyst composition over monolith surface.
Still another object of the present invention is to bring about catalytic conversion of
industrial pollutants.
Still another object of the present invention is to bring about catalytic conversion of a
gas comprising hydrocarbons, carbon monoxide and nitrogen oxide.
Statement of the Invention
The present invention is in relation to a metal ionic catalyst composition, said
composition represented by formula, Cei-x-y-zMxNyKz02-6 wherein, x is 0-0.09; y is 0-
0.09; z is 0-0.09; 5 is 0.01-0.09; and M, N, K is a metal; a process to obtain a metal
ionic catalyst composition of the formula, Cei-x-y-zMxNyKz02-6 wherein, x is 0-0.09; y is
0-0.09; z is 0-0.09; 5 is 0.01-0.09; and M, N, K is a metal, said process comprising
steps of dissolving stoichiometric amounts of metallic salts in a solvent to obtain a
solution; and heating the solution to obtain the metal ionic catalyst composition; a
process of coating the catalyst of Formula Cei.x-y-zMxNyKzOa-s on monolithic surface,
said process comprising step of coating the solution having stoichiometric amount of
metallic salts on the surface followed by heating to obtain the coated monolith; and a
method for treating a gas at low conversion temperature using a metal ionic catalyst
composition of formula Cei.x-y-zMxNyKzOa-s.
Brief description of the accompanying drawings:
Figure 1: SEM images of bare cordierite.

Figure 2: SEM image of cordierite coated with y- AI2O3
Figure 3: SEM image of cordierite coated with Y-AI2O3 followed by Cei_xPdx02-6.
Figure 4(a): XRD pattern of bare cordierite.
Figure 4(b): XRD pattern of cordierite coated with Cei-xPdxOa-g.
Figure 5(a): XPS spectra of Pd (3d5/2,3/2)
Figure 5(b): XPS spectra Ce (3d).
Figure 6: CO oxidation by O2 over Ceo.98Pto.oiRho,oi02-6 powder catalyst concentration
of CO and O2 is 2 and 6 vol% respectively.
Figure?: % CO conversion for vol% of CO plotted as a function of temperature.
Figure 8: Percent NO conversion for 1 vol % NO by 1 vol % CO over monolith.
Figure 9: Percent C2H2 conversion for 1 vol % C2H2 by 5vol % O2 over monolith.
Figure 10: Three way catalytic performance of 10,000ppm of CO, 2000ppm of NO,
2000ppm of C2H2 in presence of Troops of O2 monolith.
Table 1: Shows the comparison between commercial available monolithic catalyst and
our monolithic catalyst in metal loading, wash coat loading and conversion temperature
of CO conversion.
Detailed description of the present invention
The present invention is in relation to a metal ionic catalyst composition, said
composition represented by formula, Cei_x-y.zMxNyKz02-5 wherein, x is 0-0.09; y is 0-
0.09; z is 0-0.09; 5 is 0.01-0.09; and M, N, K is a metal.
Another embodiment of the present invention wherein the metal is selected from a
group comprising Pd, Pt, Rh, Ru, Zr, Ni and Cu.
Yet another embodiment of the present invention wherein the catalyst is Pdo.o2Ceo,9802-
6. Pto.o5 Rho.o5Ceo.9902-6 and Ceo.98Pto.oiRho.oi02-5
Yet another embodiment of the present invention wherein the catalyst composition is in
a fine powder form.
The present invention is in relation to a process to obtain a metal ionic catalyst
composition of the formula, Cei-x-y-zMxNyKz02-5 wherein, x is 0-0.09; y is 0-0.09; z is
0-0.09; 8 is 0.01-0.09; and M, N, K is a metal, said process comprising steps of:
a) dissolving stoichiometric amounts of metallic salts in a solvent to obtain a solution; and
b) heating the solution to obtain the metal ionic catalyst composition.

Another embodiment of the present invention wherein the metal is selected from a
group comprising Pd, Pt, Rh, Ru, Zr, Ni and Cu.
Yet another embodiment of the present invention wherein Pt and Rh are derived from
H2PtCl6 and RhCb.
Still another embodiment of the present invention wherein Pt and Pd are derived from

Still another embodiment of the present invention wherein Cu and Pd are derived from
Cu (N03)2 and PdCb.
Still another embodiment of the present invention wherein heating the solution at
temperature ranging between 200-1500°C.
Still another embodiment of the present invention wherein the catalyst has a particle
size in the range of 25-30 nm.
Still another embodiment of the present invention wherein the catalyst is in fine
crystalline powder form.
The present invention is in relation to a process of coating the catalyst of formula Ce-
y.z]VIxNyKz02-5 on monolithic surface, said process comprising step of coating the
solution having stoichiometric amount of metallic salts on the surface followed by
heating to obtain the coated monolith.
Another embodiment of the present invention wherein heating at a temperature ranging
between 400-700°C.
The present invention is in relation to a method for treating a gas at low conversion
temperature using a metal ionic catalyst composition of formula Cei_x-y.zMxNyKz02-6,
Another embodiment of the present invention wherein said gas comprises carbon
monoxide, hydrocarbons and nitrogen oxide.
Yet another embodiment of the present invention wherein the carbon monoxide
conversion is 100 % at temperature less than 130 C.
Still another embodiment of the present invention wherein the hydrocarbons conversion
is 100 % at temperature less than 240°C.
Still another embodiment of the present invention wherein the nitrogen oxide
conversion is 100 % at temperature less than 175
Still another embodiment of the present invention wherein the three way conversion is
100% at temperature less than 225

Still another embodiment of the present invention wherein the composition is used for
conversion of pollutants.
The present invention is illustrated by the following examples, which are set forth to
illustrate the present invention and are not construed as limiting thereof.
Example 1
Preparation of Pto.o5Rho.o5Ceo,9902-6
For the preparation of 0.5 atom% Pt-0.5 atom% Rh in CoA, (NH4)2Ce(N03)6, HsPtCU, RhCl3.xH20 and ODH were taken in the mole ratio 0.99: 0.005 : 0.005 : 2.376 in minimum volume of water (-30 cm’) in a borosilicate dish of 130 cm"‘ capacity followed by introduction of the dish containing the redox mixture into a muffle furnace maintained at --350 ‘C. Solution burns after dehydration with a flame (-1000 °C) yielding a voluminous solid product within 2 minutes. The flame itself lasts for 10-20 seconds and within a time interval of 60 seconds the temperature falls from -1000 **C to -350 "C. Example 2
Coating the monolith with Pdo.o2Ceo,9802.a
0.06 M eerie ammonium nitrate and 0.144 M ODH with 1.2 x 10"‘ M PdCb are
dissolved in 150mL of water to get a clear solution. Monolith is first dried at about
200’C. After cooling it is dipped in the precursor solution for a few seconds. Blowing
the air shakes out excess solution. Monolith is finally fired at 450-500 ‘C. Process is
repeated until we get the desired catalyst loading. Sonication is carried out at the end to
remove blockage in the channels. Finally weight gain is calculated.
The present invention will now be further illustrated by the following Figures and examples.
which do not limit the scope of the invention in any way.
In Figure 1, 2, and 3, SEM of bare monolith, monolith coated with y- AI2O3 and monolith
with y- AI2O3 + active catalyst phase are shown. In figure 1 we see the plate like
morphology while in figure 2 we see the white porous material over the surface. Figure 3
shows the Ceo.98Pdo,o202-5 surface of cordierite. Difference in the surface morphology is
apparent.
The active catalyst phase is coated over the wash-coated honeycomb surface. In the present
investigation we have coated Ceo.ggPdo 02O2-6 over honeycomb surface.

XRD results given in the following figure 4(a) shows the XRD of bare cordierite and (b)
that of alumina + Ceo.ggPdo 0202-5- Diffraction lines due to active ceria phase are identified
in figure 4(b).
An X-ray photoelectron spectra is given in figure 5(a) and 5(b). It shows the oxidation
state of palladium is +2 and not in zero valent state. Cerium dioxide can also be seen
over cordierite surface with Ce in +4 state.
Example 3
Performance of CenQsPtnniRhooiG -fi metal ionic powder catalyst:
CO oxidation over this catalyst is carried out with 150 mg of the catalyst with 2 vol% of CO and 6 vol% of O2 and at total flow of loco/ min which gives rise to a gas hourly space velocity of 43000 hr"'. 100% conversion occurs below 130 Actual rate of CO conversion is 2x 10"‘ moles/gm/sec at 1 loc.
Rate of C2H4 oxidation over the catalyst Ceo.98Pto.oiRho.oi02-5 at 200’C is 1,2x10"‘
moles/gm/sec.
Rate of NO reduction by CO over the same active catalyst at 150’C is 1.5x10"‘
moles/gm/sec.
Example 4
Performance over Pdo.o2Ceo.9802-5 coated monolithic catalyst:
Honeycombs coated with 2%Pd/Ce02 are investigated through various catalytic
reactions like CO oxidation by O2, CO + NO reaction both in presence and absence of
O2 with different composition. Reactions are done in a temperature programmed
reaction (TPR) system. Two coated honeycombs (length 2.5cm/ honeycomb, diameter
1.876 mm and channel density is 74/ cm ) are taken in the reactor and gases are passed
through it. Total flow was kept lOOcc/min for all the studies. This gives rise to the
space velocity 55600 lif 1 hr'‘ in side the channel. Percent conversions are plotted
against the temperature.
Example: 5
Carbon monoxide oxidation:
Percent CO conversion for C0:02, Ivol % CO and Ivol % O2 at 100cc/min.(55600 lifth"
' space velocity in the channel) is given in figure 6. Clearly below 75°C CO is converted
completely to CO2. At space velocity 213000 lif'- hr"' 100% CO conversions occurs at
130’C as shown in figure 7.

NO reduction by CO:
Ivol % NO (10,000 ppm) and Ivol % CO (10,000 ppm) gas mixture at 55600 lit"' hr'
shows 100 % conversion ofNObelowl75’C as can be seen in figure 8.
Acetylene Oxidation:
Figure 9 shows the acetylene oxidation by O2 with 1 vol.% acetylene and 5 vol.%
oxygen. Clearly below 240’C, acetylene is completely converted into H2O and CO2.
Example: 6
Three-way catalytic performance over Pdo.o2Ceo.9802-6 coated honeycomb catalyst:
Three-way catalytic Reactions with Pdo.o2Ceo.9802-6 over honeycomb have been investigated. A gas mixture containing 10,000 ppm of CO, 2000 ppm of C2H2, 2000 ppm of NO and 7000 ppm of O2 is passed over the monolith at 55600 lit"' hr"' space velocity. Total reductant are equal to 12000 ppm and total oxidants are equal to 15000 ppm equivalent to [O]. 2000 ppm of NO gives 2000 equivalent of [O] and 14000 ppm of [O] from 7000 ppm of O2. Thus there is a small excess of 1000 ppm of [O]. Total conversion profile is given in figure 10. As can be seen from increase in CO2 vs. temperature curve below 225’C, total conversion of CO, NO and C2H2 occur. CO and C2H2 are converted before NO conversion. NO is fully converted below 200’C. Thus, under stoichiometric and even with -15% excess oxygen the pollutants CO, NO and 'HC (acetylene) are converted to CO2, N2 and H2O below 225’0.
The performance of the monolith is shown in Table: 1 and is found that it is extremely high at lower temperature for CO, NO as well as 'HC as compared to the current literature. The details of which can be found in reference, Indian Institute of Science Mangalore 560012.


a. Commercial varieties
b. A metal ionic catalyst composition of instant invention




We Claim:
1. A metal ionic catalyst composition, said composition represented you formula, Cei_x.y-zMxNyKz02-6 wherein, x is 0-0.09; y is 0-0.09; z is 0-0.09; 5 is 0.01-0.09; and M, N, K is a metal.
2. The composition as claimed in claim 1, wherein the metal is selected from a group comprising Pd, Pt, Rh, Ru, Zr, Ni and Cu.
3. The composition as claimed in claim 1, wherein the catalyst is Pdo.o2Ceo,9802-6, Pto.o5 Rho.o5Ceo.9902-6 and Ceo.98Pto.oiRho,oi02-5
4. The composition as claimed in claim 1, wherein the catalyst composition is in a fine powder form.
5. A process to obtain a metal ionic catalyst composition of the formula, Cei_x-y-zMxNyKz02.6 wherein, x is 0-0.09; y is 0-0.09; z is 0-0.09; 5 is 0.01-0.09; and M, N, K is a metal, said process comprising steps of:

c) dissolving stoichiometric amounts of metallic salts in a solvent to obtain a solution; and
d) heating the solution to obtain the metal ionic catalyst composition.

6. The process as claimed in claim 5, wherein the metal is selected from a group comprising Pd, Pt, Rh, Ru, Zr, Ni and Cu.
7. The process as claimed in claim 6, wherein Pt and Rh are derived from H2PtCl6 and Rhc
8. The process as claimed in claim 6, wherein Pt and Pd are derived from H2PtCl6 and
PdCb
9. The process as claimed in claim 6, wherein Cu and Pd are derived from Cu (N03)2 and PdCb.
10. The process as claimed in claim 5, wherein heating the solution at temperature ranging between 200-1500°C.
11. The process as claimed in claim 5, wherein the catalyst has a particle size in the range of 25-30 nm.
12. The process as claimed in claim 5, wherein the catalyst is in fine crystalline powder form.
13. A process of coating the catalyst of Formula Cei_x-y-zMxNyKz02-6 on monolithic surface, said process comprising step of coating the solution having stoichiometric

amount of metallic salts on the surface followed by heating to obtain the coated monolith.
14. The process as claimed in claim 13, wherein heating at a temperature ranging
between 400-700°C.
15. A method for treating a gas at low conversion temperature using a metal ionic
catalyst composition of formula Cei.x-y-2MxNyK202-6
16. The method for treating a gas as claimed in claim 15, wherein said gas comprises
carbon monoxide, hydrocarbons and nitrogen oxide.
17. The method for treating a gas as claimed in claim 15, wherein the carbon monoxide conversion is 100 % at temperature less than 130^ C.
18. The method for treating a gas as claimed in claim 15, wherein the hydrocarbons conversion is 100 % at temperature less than 240*^ C.
19. The method for treating a gas as claimed in claim 15, wherein the nitrogen oxide
conversion is 100 % at temperature less than 175^ C.
20. The method for treating a gas as claimed in claim 16, wherein the three way
conversion is 100 % at temperature less than 225 C.
21. The method for treating as claimed in claim 15, wherein the composition is used for
conversion of pollutants.


Documents:

0106-che-2006 complete specification as granted.pdf

106-CHE-2006 CORRESPONDENCE OTHERS.pdf

106-CHE-2006 CORRESPONDENCE PO.pdf

106-che-2006 correspondence-others.pdf

106-CHE-2006 FORM 18.pdf

106-che-2006 form-3.pdf

106-che-2006 pct.pdf

106-CHE-2006 PETITIONS.pdf

106-che-2006-abstract.pdf

106-che-2006-claims.pdf

106-che-2006-correspondnece-others.pdf

106-che-2006-correspondnece-po.pdf

106-che-2006-description(complete).pdf

106-che-2006-drawings.pdf

106-che-2006-form 1.pdf

106-che-2006-form 26.pdf

106-che-2006-form 3.pdf

106-che-2006-form 5.pdf

106-che-2006-form 9.pdf

EXAMINATION REPORT REPLY.PDF


Patent Number 237260
Indian Patent Application Number 106/CHE/2006
PG Journal Number 51/2009
Publication Date 18-Dec-2009
Grant Date 11-Dec-2009
Date of Filing 24-Jan-2006
Name of Patentee INDIAN INSTITUTE OF SCIENCE
Applicant Address SOLID STATE AND STRUCTURAL CHEMISTRY UNIT, BANGALORE 560 012, KARNATAKA, INDIA.
Inventors:
# Inventor's Name Inventor's Address
1 HEGDE NO:288, KEB LAYOUT,GELDALAHALLI, BANGALORE 560 012, KARNATAKA, INDIA.
2 K.C. PATIL RETIRED PROFESSOR, IPC, NO. 440, 5TH CROSS, TATA NAGAR, KODIGEHALLI, BANGALORE 560 092, KARNATAKA, INDIA.
3 SCDHANSHU SHARMA SOLID STATE AND STRUCTURAL CHEMISTRY UNIT, BANGALORE 560012, KARNATAKA INDIA.
PCT International Classification Number C10G73/38
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA