Title of Invention

A METHOD OF MANUFACTURING IN-SITU CATALYSED CARBON USEFUL AS CARRIER MATERIAL CARBON

Abstract The present invention provides an energy, time and cost effective method of manufacturing carrier material with all required physico-chemical properties for effective catalyst distribution. The method involves dissolving precursor material such as glycine in water, adding and mixing surfactant and catalyst salt solution. The mixture is pre-heated to a temperature in the range of 60 to 70 °C for about 30 minutes and heated to a final temperature in the range of 280 to 350 °C for 2 to 5 minutes. The formed product is heat treated in an inert atmosphere, cooled down to room temperature and stored. The catalyzed carbon will be useful as carrier material carbon for fine chemicals, pharmaceuticals and fuel cell industries and also useful to prepare various catalysts with carbon as a carrier material.
Full Text This invention relates to a method of manufacturing in-situ catalyzed carbon useful as carrier material carbon. This invention particularly relates to a method of preparing in-situ platinized carbon useful as carrier material carbon.
The catalyzed carbon will be useful as carrier material carbon for fine chemicals, pharmaceuticals and fuel cell industries and also useful to prepare various catalysts with carbon as a carrier material.
One of the challenges in low temperature fuel cells like PEM and DMFC is to develop an energy, time and cost effective method of manufacturing carrier material with all required physico-chemical properties for effective catalyst distribution in one step. The carrier material not only provides good electronic conduction but also area with required pore structure and surface properties for effective catalyst distribution. The carrier material carbon used in the preparation of fuel cell electrodes provides structures but does not participate in the electrochemical process.
The conventional processes to fabricate catalyst electrodes involved catalyzation of pre-synthesized carbon powders. The carbon powders were synthesized separately through various methods. Some of the methods like vacuum pyrolysis are costlier and the others with poor surface properties. The surface properties are improved by additional chemical and / or heat treatment methods involving energy, time and cost.
One hitherto known prior art method of producing lamp black is by the partial combustion of pitch resin or tung oil, or fatty substances, such as naphthalene, in a vessel within a collector hood made of paper. The smoke is deposited on the inside of the hood, which is then removed by mechanical means. The collected soot is then heated several times to a very high temperature in order to remove the impurities. The product has a surface area of 20-25 m2/g.
Another hitherto known prior art method of preparing carbon black, amorphous carbon is by the thermal decomposition of natural hydrocarbons with a surface area of 90 - 460 m2/g.
The major drawback of the conventional method of preparing catalyzed carbon is pre-synthesized carbon with the required surface morphology was taken and catalyzed by different known methods, such as chemical reduction, vapor deposition, electro-deposition. This is a two-step process and some of the methods to synthesis carbon with the required surface morphology itself have to follow additional chemical or physical process. Moreover the pre-synthesized carbon may not have the same surface morphology which was taken for catalyzation, as the freshly prepared one due to time gap between these two processes.
There is a definite need to circumvent these problems associated with the above said hitherto known prior art conventional methods of preparing carbon and catalyzation of the same.
The main objective of the present invention is to provide a method of manufacturing in-situ catalyzed carbon useful as carrier material carbon which obviates the draw backs of the hitherto known prior art conventional methods of preparing carbon and catalyzation of the same, as detailed above.
Another objective of the present invention is to provide a novel method of in-situ carbon preparation and catalyzation of the same to obtain in-situ platinized carbon useful as carrier material carbon, which circumvents the draw backs as detailed above.
Yet another objective of the present invention is to provide, a method wherein fresh carbon and fresh catalyst surface interact and form a catalyzed carbon. The present invention provides a novel method for manufacturing of in-situ catalyzed carbon useful as carrier material carbon. The present invention provides an energy, time and cost effective method of manufacturing carrier material with all required physico-chemical properties for effective catalyst distribution. The method involves dissolving precursor material such as glycine in water, adding and mixing surfactant and catalyst salt solution. The mixture is preheated to a temperature in the range of 60 to 70 °C for about 30 minutes and heated to a final temperature in the range of 280 to 350 °C for 2 to 5 minutes. The formed product is heat treated in an inert atmosphere, cooled down to room temperature and stored. The catalyzed carbon will be useful as carrier material carbon for fine chemicals, pharmaceuticals and fuel cell industries and also useful to prepare various catalysts with carbon as a carrier material.
Accordingly the present invention provides a method of manufacturing in-situ catalyzed carbon useful as carrier material carbon, which comprises; characterized in dissolving precursor material, such as glycine in water at room temperature, adding and mixing surfactant followed by adding and mixing catalyst solution, warming the resultant mixture to a temperature in the range of 60 to 70 °C for a period of the order of 30 minutes, followed by heating to a reaction temperature in the range of 280 to 350 °C for a period of 2 to 5 minutes to obtain the resultant product platinized carbon, heat treating the product so obtained in an inert atmosphere , allowing to cool to room temperature.
In an embodiment of the present invention, the concentration of the precursor solution is in the range of 0.1 to 1 molar.
In another embodiment of the present invention, the dissolving of precursor material, such as glycine in water is effected at room temperature in the range of 25 to 35 °C, under magnetic stirring. In yet another embodiment of the present invention, the mixing of precursor solution, surfactant and catalyst solution is done under magnetic stirring.
In still another embodiment of the present invention, the surfactant used is such as triton X-100.
In still yet another embodiment of the present invention, the surfactant concentration is in the range of 0.1 to 1 wt percentage.
In a further embodiment of the present invention, the water is triple distilled water.
In a still further embodiment of the present invention, the catalyst solution used is hexacholroPlatinic acid.
In a yet further embodiment of the present invention, the concentration of the catalyst solution is in the range 1 to 10 molar.
In another embodiment of the present invention, the reaction is carried out at atmospheric conditions.
In yet another embodiment of the present invention, the product platinized carbon is heat treated in inert atmosphere, such as nitrogen atmosphere at a temperature in the range of 200 to 300 °C for a period in the range of 30 to 90 minutes.
Yields were compared with the respective theoretical values as calculated from the respective stochiometric equations 1 with the assumption that no carbon atom in the precursor is converted into gaseous product.
(Formula Removed)
The yield and particle size highly depend on acid / basicity of the precursor glycine.
Different concentrations of HNO3 were added to glycine (sulphuric acid and hydrochloric acid are not used in order to avoid contamination due to chloride and sulphur). The results of effect of nitric acid concentration on carbon yield are as shown in table 1 with respective particle size values also. It is interesting to note that, not only the yield but also the particle size follows the same reducing trend with variation in nitric acid concentration.
Table 1
Variation in yield and particle size with respect to nitric acid concentration

(Table Removed)
The observed trend of effect of nitric acid concentration on carbon yield is as shown in figure 1 of the drawings accompanying this specification. At the concentration of 1N HNO3, yield was reduced by ~50% and particle size by four times than without any HNO3 addition. Beyond this acid concentration no appreciable change in yield and particle size is observed. This is because that the addition of HNO3 to glycine at room temperature gives hydroxy acid as shown below.
(Table Removed)
Because of this hydroxy acid formation, the molecule has both carboxylic and alcoholic group, which is more prone to conversion into oxide of carbon. From the stochiometric equation it is calculated that, 63g (One mole) of HNO3 is needed for 75 g (one mole) of glycine to get one mole of hydroxy acid. For the experimental purpose we have dissolved 3 g of glycine in 40 ml of 1 N nitric acid, the amount of HNO3 exactly needed for complete conversion to hydroxy acid. At this concentration of nitric acid carbon yield and particle size values reached minimum and further increase in acid concentration has no appreciable effect. This observation confirms that the yield and particle size values reduced till the glycine is completely converted into hydroxy acid and after full conversion no appreciable change is observed, that is; the structural and chemical change just before the combustion/decomposition reaction plays an important role in deciding the yield and particle size of the product carbon.
Accordingly the present invention provides a novel method of in-situ carbon preparation and catalyzation of the same to obtain in-situ platinized carbon useful as carrier material carbon. The non-obvious inventive steps of the present invention provides a novel method wherein fresh carbon and fresh catalyst surface interact and form a catalyzed carbon useful as carrier material carbon.
The following examples are given by way of illustration of the method of the present invention for manufacturing in-situ catalyzed carbon and therefore should not be constructed to limit the scope of the present invention.
Example 1
One molar solution of glycine was prepared by dissolving 3.068 grams of glycine powder with 20 ml of 0.1wt percentage of Triton X-100 in triple distilled water, and stirred with a magnetic stirrer for 15 seconds with out vortex. 60 ml of 0.01 M hexacholroPlatinic acid was added and once again mixed with magnetic stirrer for about 5 minutes. The mix was taken in a pyrex glass crucible and introduced in to a muffle furnace and warmed at 60 ° C for about 30 minutes so that minimum amount of left out solution was less than 10 ml. Then the temperature of the muffle furnace was raised quickly to the final temperature of 280 °C. The reaction was completed after 5 minutes. The furnace was put off and the formed product platinized carbon was then heat treated in Nitrogen atmosphere for one hour at 250 °C. The yield was found to be one gram along with the platinum catalyst.
Example 2
One molar solution of glycine was prepared by dissolving 9.204 grams of glycine powder with 60 ml of 0.1 wt percentage of Triton X-100 in triple distilled water, and stirred with a magnetic stirrer for 15 seconds with out vortex. 180 ml of 0.01 M hexacholroPlatinic acid is added and once again mixed with magnetic stirrer for about 5 minutes. The mix was taken in a pyrex glass crucible and introduced
in to a muffle furnace and warmed at 70 °C for about 30 minutes so that minimum amount of left out solution was less than 10 ml. Then the temperature of the muffle furnace was raised quickly to the final temperature of 350 °C. The reaction was completed after 2 minutes. The furnace was put off and the formed product platinized carbon was then heat treated in Nitrogen atmosphere for one hour at 250 °C. The yield was found to be 2.93 grams along with the platinum catalyst.
The particle size of the carbon material obtained was of the order of 5 µm.
In figures 2 (a) and 2 (b) of the drawings accompanying this specification are shown the X-ray diffractogram of carbon and catalyzed carbon respectively.
It was observed from figure 2 (a), that the carrier material carbon is amorphous and from figure 2 (b), peaks at 26 value of 40 (111), 47 (200), 67 (220) and 82 (311) occurred in the diffractogram are due to fcc Platinum crystal structure. The mean particle size of platinum was determined using Scherrer's equation and found to be 47.84 °A.
The main advantages of the method of the present invention for manufacturing in-situ catalyzed carbon useful as carrier material carbon are:
1. The catalyzed carbon will be useful as carrier material carbon for fine chemicals, pharmaceuticals and fuel cell industries and also useful to prepare various catalysts with carbon as a carrier material.
2. An energy, time and cost effective method of manufacturing carrier material with all required physico-chemical properties for effective catalyst distribution in one step.
3. The carrier material not only provides good electronic conduction but also area with required pore structure and surface properties for effective catalyst distribution.
4. One step economical process for the synthesis of carbon with the required surface morphology.
5. A novel method of in-situ carbon preparation and catalyzation of the same to
obtain in-situ platinized carbon useful as carrier material carbon, which
circumvents the draw backs as detailed above.
6. A method wherein fresh carbon and fresh catalyst surface interact and form a
catalyzed carbon.









We claim:
1. A method of manufacturing in-situ catalyzed carbon useful as carrier material carbon, which comprises; Characterized in dissolving precursor material, glycine in water at room temperature, adding and mixing surfactant followed by adding and mixing catalyst solution, warming the resultant mixture to a temperature in the range of 60 to 70 °C for a period of the order of 30 minutes, followed by heating to a reaction temperature in the range of 280 to 350 °C for a period of 2 to 5 minutes to obtain the resultant product platinized carbon, heat treating the product so obtained in an inert atmosphere, allowing to cool to room temperature.
2. A method as claimed in claim 1, wherein the concentration of the precursor solution is in the range of 0.1 to 1 molar.
3. A method as claimed in claims 1-2, wherein the dissolving of precursor material, glycine in water is effected at room temperature in the range of 25 to 35 °C, under magnetic stirring.
4. A method as claimed in claims 1-3, wherein the mixing of precursor solution, surfactant and catalyst solution is done under magnetic stirring.
5. A method as claimed in claims 1-4, wherein the surfactant used is non-ionic triton X-100.
6. A method as claimed in claims 1-5, wherein the surfactant concentration is in the range of 0.1 to 1 wt percentage.
7. A method as claimed in claims 1-6, wherein the water is triple distilled water.
8. A method as claimed in claims 1-7, wherein the catalyst solution used is hexacholroPlatinic acid.
9. A method as claimed in claims 1-8, wherein the concentration of the catalyst solution is in the range 1 to 10 molar.

10. A method as claimed in claims 1-9, wherein the reaction is carried out at atmospheric conditions.
11. A method as claimed in claims 1-10, wherein the product platinized carbon is heat treated in inert atmosphere, such as nitrogen atmosphere at a temperature in the range of 200 to 300 °C for a period in the range of 30 to 90 minutes.
12. A method of manufacturing in-situ catalyzed carbon useful as carrier material carbon, substantially as herein described with reference to the examples and drawings accompanying this specification.

Documents:

1479-DEL-2004-Abstract-(27-08-2010).pdf

1479-del-2004-abstract.pdf

1479-DEL-2004-Claims-(27-08-2010).pdf

1479-del-2004-claims.pdf

1479-DEL-2004-Correspondence-Others-(27-08-2010).pdf

1479-del-2004-correspondence-others.pdf

1479-DEL-2004-Description (Complete)-(27-08-2010).pdf

1479-del-2004-description (complete).pdf

1479-del-2004-drawings.pdf

1479-del-2004-form-1.pdf

1479-del-2004-form-18.pdf

1479-del-2004-form-2.pdf

1479-DEL-2004-Form-3-(27-08-2010).pdf

1479-del-2004-form-3.pdf

1479-del-2004-form-5.pdf


Patent Number 243908
Indian Patent Application Number 1479/DEL/2004
PG Journal Number 46/2010
Publication Date 12-Nov-2010
Grant Date 10-Nov-2010
Date of Filing 09-Aug-2004
Name of Patentee COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH
Applicant Address RAFI MARG, NEW DELHI-110 001, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 SUBBARAJU DHEENADAYALAN CENTRAL ELECTROCHEMICAL RESEARCH INSTITUTE, KARAIKUDI-630 006, TAMIL NADU, INDIA
2 RAJAM PATTABIRAMAN CENTRAL ELECTROCHEMICAL RESEARCH INSTITUTE, KARAIKUDI-630 006, TAMIL NADU, INDIA
3 RAMASAMY CHANDRASEKARAN CENTRAL ELECTROCHEMICAL RESEARCH INSTITUTE, KARAIKUDI-630 006, TAMIL NADU, INDIA
PCT International Classification Number C01B 31/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA