The catalyst preparation method of the catalyst and the method of purification of enriched hydrogen gas mixtures of carbon monoxide

 

(57) Abstract:

The invention relates to a catalyst, the method of its preparation and process for the catalytic purification method from the carbon monoxide-enriched hydrogen gas mixtures. Hydrogen is one of the most important industrial gases. It is used in various fields of chemical industry, including hydrogen energy, for example, as fuel for fuel cells. Task to be solved by the present invention is directed, is to increase the efficiency of oxidation of CO in hydrogen-rich gas mixtures to less than 10 ppm. The task is solved through the use of more active and selective catalysts based on noble metals ( platinum, palladium, ruthenium, rhodium, iridium), mainly of ruthenium and platinum, deposited on a graphite-like carbon carrier in an amount not less than 0.01 wt. percent, mainly of 0.05-5 wt.%, and catalysts on the basis of mixtures or alloys of noble metals (platinum, palladium, ruthenium, rhodium, iridium) containing two or more metal deposited on a graphite-like carbon carrier with the total metal content not less than 0.01 wt.%. 3 S. and 8 C.p. f-crystals, 5 PL.

Fuel cells are seen as a real alternative to the automobile internal combustion engines, because they have much higher efficiency, they are quiet, work at a sufficiently low temperature (80-110oC).

There are two main method of supplying hydrogen to the fuel cell (J. V. Ogden, M. M. Steinbugler, T. G. Kreutz, A Comparison of Hydrogen, Methanol and Gasoline as Fuels for Fuel Cell Vehicles: Implications for Vehicle Design and Infrastructure Development, Journal of Power Sources, vol.79 (1999) pp. 143-168).

By the first method, the hydrogen serves in pure form from the storage tanks, where it is compressed. The disadvantage of this method is the necessity of using equipment operating at high pressures, which adds cost and complexity to the process and increases the consumption of plants.

On the second way hydrogen is produced in a catalytic chemical process of substances vehicles hydrogen directly on a mobile vehicle. As carriers of hydrogen is the most promising hydrocarbon nature of the AI in the hydrogen-containing recycle gas mixture. The mixture typically consists of N2, CO2N2N2Oh and to ~1 vol. %. It is known that the carbon monoxide at a concentration of more than about 0.001. % (10 ppm) is poison to the fuel electrode. Therefore, such vodorodsoderzhashchee gas mixture must be cleaned of carbon monoxide before it is supplied to the fuel cell. From all existing methods such cleaning is the most advanced purification by oxidation of carbon monoxide.

When carrying out such cleaning are two reactions:

2CO+O2-->2SD2< / BR>
2H+O2-->2H2O(gas)

Their course is customary to characterize the selectivity for oxygen. This selectivity is equal to the ratio of the amount of oxygen spent on the oxidation of CO, to the consumed amount of oxygen in both reactions:

< / BR>
Currently known method (prototype) the reaction of oxidation of carbon monoxide in the presence of hydrogen, which catalyst is used Pt supported on zeolites (US Patent 6168772, 01 31/20, 2001). The content of platinum in that the catalyst is 6.4 wt. %. Work in the field of CO oxidation in hydrogen-rich gas mixtures (Igarashi N., Uchida H., Suzuki, M., Sasaki Y., Watanabe M. Removal of carbon monoxide from hydrogen-rich fuels by selective oxidation of CO in Reformed Gases. // Chem. Lett. (1995) 25) showed that this catalyst operates at temperatures exceeding 200o(I.e., approximately 100oWith higher than the operating temperature of the fuel cell). Another disadvantage of this catalyst is relatively high molar ratio of oxygen to carbon monoxide (O2:CO=2:1). Thus, for the oxidation of CO below 10 ppm required a fourfold excess OF2from the desired stoichiometry. Thus there is a decrease in the selectivity of the process and thus there is a loss of hydrogen fuel.

Recent developments in this area were aimed at improving the selectivity of the Pt catalyst supported on zeolite for oxidation of CO in the enriched hydrogen gas mixtures (H. Igarashi, H. Uchida, Suzuki M. Sasaki Y., Watanabe M, Removal of carbon monoxide from hydrogen-rich fuels by selective oxidation over platinum catalyst supported on zeolite. // Applied Catal. A: General, 159, (1997), 159-169). This are trying to achieve by changing the reactor design and careful control of temperature and flow rate of oxygen into the reactor. One such attempt is the use of multi-stage reactor for selective oxidation with the optimization of the amount of oxygen at each stage. The disadvantage of this method afleet improve the cleaning process - is the use of more active and selective catalysts than currently used Pt/Zeolite.

Task to be solved by the present invention is directed, is to increase the efficiency of oxidation of CO in hydrogen-rich gas mixtures to less than 10 ppm.

The task is solved through the use of more active and selective catalysts based on noble metals (platinum, palladium, ruthenium, rhodium, iridium), mainly of ruthenium and platinum, deposited on a graphite-like carbon carrier in an amount not less than 0.01 wt. %, mainly 0.05-5 wt. %, and catalysts on the basis of mixtures or alloys of noble metals (platinum, palladium, ruthenium, rhodium, iridium) containing two or more metal deposited on a graphite-like carbon carrier with the total metal content not less than 0.01 wt. %. Graphite-like carbon material is a three-dimensional carbon matrix with the pore volume of 0.2-1.7 cm3/g formed by the belt layers of carbon with a thickness and radius of curvature having a true density equal 1,80-2,10 g/cm3, x-ray density 2,112-2,236 g/cm3and porous structure with a pore distribution with a maximum 649, SW/10, 1990; the Patent of the Russian Federation 1706690, SW/10, 1992).

The task is also solved by a method of preparation of the catalyst for purification of enriched hydrogen gas mixtures of carbon monoxide by oxidation of carbon monoxide with oxygen, application of complex compounds of noble metals such as Ptn(CO)2n, Ru[(CO(NH2)2)]Cl2, RuOHCl3, [PD(H20)4](NO3)2and so on, on the graphite-like carbon material, which is a three-dimensional carbon matrix with the pore volume of 0.2-1.7 cm3/g formed by the belt layers of carbon with a thickness and radius of curvature having a true density equal 1,80-2,10 g/cm3, x-ray density 2,112-2,236 g/cm3and porous structure with a pore distribution with a maximum in the range or biporous structure with pore distribution with an additional maximum in the range .

The task is also solved by a method of purification of enriched hydrogen gas mixtures of carbon monoxide by oxidation of carbon monoxide with oxygen on the catalyst described above. The process is carried out at a molar ratio of oxygen to carbon monoxide, present in the enriched hydrogen gas mixture from 0.5 to 3 at a temperature of not ve not less than about 0.1. % of carbon dioxide and at least about 0.1. % water vapor.

The process of purification of hydrogen-containing gas mixtures of carbon monoxide is carried out in a flow reactor with a single layer of catalyst. The reactor is a quartz tube with an inner diameter of 8 mm Layer consists of 0.6 g of catalyst was mixed with 1 g of inert material SiC. As catalysts take Pt, Ru on graphite-like carbon carrier (Pt/C, Ru/C). The volumetric rate varies in the range of 1000-100000 h-1the temperature of the catalyst layer in the range of 20-250oC. the Reaction proceeds in the range of pressures of 1-10 ATM. The reaction gas mixture has a composition of about 10-100. % H2, 0-30 about. % CO2, 0.01 to about 2. % Of CO, 0.01-5 about. % O2, 0-10 about. % H2O, 0-90 about. % N2.

The invention is illustrated by the following examples for the preparation of the catalysts defined above composition and examples describing the results of the tests of the catalysts in the oxidation of CO in the presence of large quantities of hydrogen.

I. Preparation of catalysts

Example 1. Get sample 0.2 wt. % Ru/C

a) chloride complex of ruthenium

22 mg RuOHCl3dissolve in 5 ml of 2% hydrochloric acid at a temperature of 100oWith that and heated on a water bath with constant stirring until complete drying. Obtained air-dry the sample incubated 1.5 h at 100oWith air and then restore in a stream of hydrogen at 400oC for 4 h

b) urea complex of ruthenium

To 22 mg RuOHCl3add 32 mg hydroxylamine sulfate, 58.5 mg of urea and 2 ml of water. The suspension is boiled for 2 hours until its complete dissolution. 5 g of graphite-like carbon material is poured thus prepared solution and perform all subsequent operations under paragraph 1.a).

Example 2. Get sample 0.5 wt. % Ru/C

The sample prepared similarly to p. 1.b), but for preparation of the impregnating solution to 55 mg RuOHCl3add 80 mg hydroxylamine sulfate, 146.25 mg urea and 5 ml of water. All subsequent operations are performed according to the point 1.b).

Example 3. Get sample 1 wt. % Ru/C

The sample prepared similarly to p. 1.b), but for preparation of the impregnating solution to 110 mg RuOHCl3add 160 mg hydroxylamine sulfate, 292.5 mg of urea and 10 ml of water. All subsequent operations are performed according to the point 1.b).

Example 4. Get sample 2 wt.% Ru/C

The sample prepared similarly to p. 1.b), but for the preparation of impregnating restorepeace perform according to the point 1.b).

Example 5. Preparation of sample 1 wt. % Pt/C

9.9 g of graphite-like carbon material is placed in a flask, poured 40 ml of acetone and vacuum to remove air from the pores of the carrier. Then fill the flask with carbon monoxide and with vigorous stirring, add 18 ml of an acetone solution of carbonyl cluster platinum - H2[PT3(CO)6]5with a concentration of 5.7 mg Pt/ml After stirring the suspension for 2 h, the solution is drained and the catalyst was dried in air at 80oC for 2H.

Example 6. Sample preparation 0.5 wt.% Pt/C

The catalyst is prepared analogously p. 5, but to 4.5 g of graphite-like carbon material is poured 20 ml of acetone and vacuum to remove air from the pores of the carrier. Then fill the flask with carbon monoxide and with vigorous stirring, add 9 ml of an acetone solution of carbonyl cluster platinum - H2[Pt3(CO)6]5with a concentration of 5.7 mg Pt/ml

After stirring the suspension for 2 h, the solution is drained and the catalyst was dried in air at 80oC for 2H.

Example 7. Sample preparation 0.5 wt. % (Pt+Ru)/C

a) 0.2 wt. % Ru and 0.3 wt. % Pt

The application of EN carried out similarly to p. 1.a). Then is zdwhu from the pores of the carrier. Then fill the flask with carbon monoxide and with vigorous stirring, 3 ml of an acetone solution of carbonyl cluster platinum H2[Pt3(CO)6]5with a concentration of 5.7 mg Pt/ml After stirring the suspension for 2 h, the solution is drained and the catalyst was dried in air at 80oC for 2 h

b) 0.3 wt. % Ru and 0.2 wt. % Pt

The application of EN carried out similarly to p. 1. but 33 mg RuOHCl3dissolve in 5 ml of 2% hydrochloric acid at a temperature of 100oC for two hours. 5 g of graphite-like carbon material is poured thus prepared solution and heated on a water bath with constant stirring until complete drying. All subsequent operations are performed according to paragraph 1.a). Pt put on p. 5, but 5 g of the sample is poured 20 ml of acetone and vacuum to remove air from the pores of the carrier. Then fill the flask with carbon monoxide and with vigorous stirring, 2 ml of an acetone solution of carbonyl cluster platinum N2[PT3(CO)6]5with a concentration of 5.7 mg Pt/ml After stirring the suspension for 2 h, the solution is drained and the catalyst was dried in air at 80oC for 2H.

II. Test EUT in flow reactor catalyst of 0.5 wt. % Pt/C at flow rate of 6000 h-1and atmospheric pressure. The reaction gas mixture consists of at 0.59 on. %, 0.69 about. % O2and 98.72 about. % H2. The results are shown in Table 1.

Example 9. A process similar to the one described in Example 8, is performed on the catalyst 1.0 wt. % Pt/C. the Reaction gas mixture consists of about 0.6. %, About 0.6. % O2and 98.8 about. % H2. The results are shown in Table 2.

Example 10. A process similar to the one described in Example 8, is performed on the catalyst 2.0 wt. % Ru/C. the Reaction gas mixture consists of 0.53 about. %, 0.61 about. % O2, about 20. % CO2, 3 vol. % H2Oh and 75.86 about. % H2. The results are presented in Table 3.

Example 11. A process similar to the one described in Example 8, is performed on the catalyst 1.0 wt. % Ru/C. the Reaction gas mixture consists of about 0.55. %, About 0.75. % O2, about 20. % CO2, 3 vol. % H2Oh and 75.7 about. % H2. The results obtained are presented in Table 4.

Example 12. A process similar to the one described in Example 8, is performed on the catalyst (0.3 wt. % Ru + 0.2 wt. % Pt/C. the Reaction gas mixture consists of 0.56 about. %, 0.73 about. % O2and 98.71 about. % H2. The results are presented effective to carry out the cleaning process enriched hydrogen gas mixtures to the level of CO content less than 10 ppm.

1. The catalyst for purification of enriched hydrogen gas mixtures of carbon monoxide by oxidation of carbon monoxide by oxygen, containing precious metals, characterized in that as the active components of catalysts containing noble metals in the amount of 0.05-5.0 wt.%, deposited on the graphite-like carbon media, representing a three-dimensional carbon matrix with the pore volume of 0.2-1.7 cm3/g formed by the belt layers of carbon with a thickness and radius of curvature having a true density equal 1,80-2,10 g/cm3, x-ray density 2,112-2,236 g/cm3and porous structure with a pore distribution with a maximum in the range or biporous structure with pore distribution with an additional maximum in the range

2. The catalyst p. 1, characterized in that the active ingredient it contains one or at least two metals from the series: platinum, palladium, ruthenium, rhodium, iridium.

3. The method of preparation of the catalyst for purification of enriched hydrogen gas mixtures of carbon monoxide by oxidation of carbon monoxide with oxygen, including the application of noble metal on a carrier, characterized in that the catalyst is prepared applying the three-dimensional carbon matrix with the pore volume of 0.2-1.7 cm3/g formed by the belt layers of carbon with a thickness and radius of curvature having a true density equal 1,80-2,10 g/cm3, x-ray density 2,112-2,236 g/cm2and porous structure with a pore distribution with a maximum in the range or biporous structure with pore distribution with an additional maximum in the range

4. The method according to p. 3, characterized in that as the active component, the catalyst contains one or at least two metals from the series: platinum, palladium, ruthenium, rhodium, iridium.

5. The method according to PP.3 and 4, characterized in that the catalyst contains an active ingredient in amount of 0.05-5.0 wt.%.

6. The method of purification of enriched hydrogen gas mixtures of carbon monoxide by oxidation of carbon monoxide with oxygen, wherein the catalyst using the catalyst according to any one of paragraphs.1-5.

7. The method according to p. 6, wherein the process is carried out at a molar ratio of oxygen to carbon monoxide, present in the enriched hydrogen gas mixture from 0.5 to 3.

8. The method according to PP.6 and 7, characterized in that the process is carried out at a temperature not lower than the 20oC.

9. The method according to PP.6-8, characterized those who returned enriched hydrogen gas mixture contains not less than 0.1 vol.% carbon dioxide.

11. The method according to PP.6-10, characterized in that the purified enriched hydrogen gas mixture contains not less than 0.1 vol.% water vapour.

 

Same patents:

The invention relates to the field of combustion and can be used to produce steam or hot water and carbon dioxide

The invention relates to inorganic chemistry, namely to receive the carbon dioxide, which can be used in the food industry, as a component of fire extinguishing compositions in gas lasers and in the production of various substances

The invention relates to the production of carbon dioxide labeled with carbon-14, which is used in research in chemistry, biology and medicine

The invention relates to the field of chemical analysis and can be used for quantitative transfer of molecular oxygen in carbon dioxide, for example, to transfer oxygen obtained from the analyzed samples of their fluoridation in carbon dioxide for subsequent mass spectrometric determination of the isotopic composition of oxygen

The invention relates to processes for obtaining carbon dioxide from combustion gases and may find application in chemical technology for the production of carbon dioxide with low impurities content

The invention relates to a catalyst used for the synthesis of mercaptan from methanol and hydrogen sulfide, as well as to a method for producing this catalyst

The invention relates to methods of producing the catalyst for purification of exhaust gases of internal combustion engines

The invention relates to a catalyst for the synthesis of methylmercaptan and method thereof

The invention relates to catalysts and methods of producing oxide catalysts used in the processes of deep oxidation of organic compounds and carbon monoxide in the gas emissions from industrial productions

The invention relates to catalysts for efficient removal of nitrogen oxides from waste gases with a high content of oxygen, the method of producing catalysts and the method of purification of waste gases from nitrogen oxides

The invention relates to the field of preparation of microspherical alumina carriers for catalysts

The invention relates to catalytic chemistry, in particular to catalysts for the synthesis of olefins from monohalogenated paraffins, and may find application in the disposal of chlorinated organic wastes, as well as in the production of synthetic rubber

The invention relates to a deposited palladium-gold catalyst for production of vinyl acetate from ethylene, acetic acid and oxygen

The invention relates to the production of palladium catalysts for selective hydrogenation of organic compounds

The invention relates to a method for heterogeneous bimetallic palladium-gold catalyst to obtain a vinyl acetate from ethylene, acetic acid and oxygen
Up!