Preparation method of cerium-aluminum composite oxide with low cost and large specific surface area

Abstract

The invention relates to a solid solution supported catalyst, and in particular to a preparation method of a cerium-aluminum composite oxide with low cost and large specific surface area. The preparation method is characterized by comprising the following steps: (1) adding alumina hydrate in 100-170g / L of a cerium chloride aqueous solution, pulping to obtain a mixed liquid, adding 0.1-1 percent of a surfactant (by weight percentage) of the mixed liquid, uniformly stirring, putting the mixed liquid in a constant-temperature tank, and standing for 1-2h; (2) adding ammonia water or ammonium carbonate in a feed solution subjected to treatment in the first step, and controlling a pH value to be 8-10 to obtain gelatinous precipitates; (3) washing the gelatinous precipitates obtained in the second step with deionized water, and carrying out dehydration; (4) putting a product obtained through dehydration in the third step in a kiln, and roasting the product under the condition with the temperature being 500-700 DEG C for 4-6h; and (5) grinding the product subjected to roasting until the maximum particle size is 10 microns to obtain the cerium-aluminum composite oxide with large specific surface area. The preparation method is low in cost of raw materials and simple in technological process and is beneficial to large scale industrial production.

Description

technical field

[0001] The invention relates to a solid solution carrier catalyst, in particular to a method for preparing a low-cost and large specific surface area cerium-aluminum composite oxide. Background technique

[0002] As an important catalyst carrier, cerium oxide has unique oxygen storage capacity and other excellent properties. Cerium ions generate Ce in an oxidizing or reducing atmosphere 3+ and Ce 4+ Oxidation-reduction reaction between them, so as to realize the function of oxygen storage and oxygen release, which is helpful to realize the catalytic conversion of automobile exhaust, etc., but pure cerium oxide is very easy to sinter at high temperature, resulting in a decline in the ability to store and release oxygen. Doping an appropriate amount of zirconium to form a cerium-zirconium-based oxide solid solution can greatly improve the high-temperature aging resistance and oxygen storage and release properties of cerium oxide. Therefore, research on the sy...

Examples

Embodiment 1

[0021] (1) In the aqueous solution of 100g / L cerium chloride, add aluminum oxide hydrate, beat to obtain mixed solution, add the surfactant (polyethylene glycol) that is 0.5% of mixed solution in parts by weight, after stirring Place it in a constant temperature tank and let it stand for 1.5 hours, and the temperature of the constant temperature tank is constant at 45°C;

[0022] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 60 parts by weight of cerium oxide, 40 parts by weight of aluminum oxide;

[0023] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 9, can obtain a kind of colloidal precipitate;

[0024] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0025] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 500°C for 6 hours;

[0026] (5) Grinding the products ...

Embodiment 2

[0029] (1) In the aqueous solution of 150g / L cerium chloride, add aluminum oxide hydrate, make a slurry to obtain the mixed solution, add the surfactant (oleic acid) that is 0.2% of the mixed solution in parts by weight, stir evenly and place it at a constant temperature Stand in the tank for 2 hours, and the temperature of the constant temperature tank is constant at 40°C;

[0030] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 30 parts by weight of cerium oxide, 70 parts by weight of aluminum oxide;

[0031] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 10, can obtain a kind of colloidal precipitate;

[0032] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0033] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 600° C. for 5 hours;

[0034] (5) Grinding the pro...

Embodiment 3

[0037] (1) In the aqueous solution of 170g / L cerium chloride, add aluminum oxide hydrate, make a slurry to obtain the mixed solution, add the surfactant (magnesium phosphate) that is 0.8% of the mixed solution in parts by weight, stir evenly and place it at a constant temperature Stand in the tank for 1 hour, and the temperature of the constant temperature tank is constant at 50°C;

[0038] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 35 parts by weight of cerium oxide, 65 parts by weight of aluminum oxide;

[0039] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 8, can obtain a kind of colloidal precipitate;

[0040] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0041] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 700°C for 4 hours;

[0042] (5) Grinding th...

technical field

[0001] The invention relates to a solid solution carrier catalyst, in particular to a method for preparing a low-cost and large specific surface area cerium-aluminum composite oxide. Background technique

[0002] As an important catalyst carrier, cerium oxide has unique oxygen storage capacity and other excellent properties. Cerium ions generate Ce in an oxidizing or reducing atmosphere 3+ and Ce 4+ Oxidation-reduction reaction between them, so as to realize the function of oxygen storage and oxygen release, which is helpful to realize the catalytic conversion of automobile exhaust, etc., but pure cerium oxide is very easy to sinter at high temperature, resulting in a decline in the ability to store and release oxygen. Doping an appropriate amount of zirconium to form a cerium-zirconium-based oxide solid solution can greatly improve the high-temperature aging resistance and oxygen storage and release properties of cerium oxide. Therefore, research on the sy...

Examples

Embodiment 1

[0021] (1) In the aqueous solution of 100g / L cerium chloride, add aluminum oxide hydrate, beat to obtain mixed solution, add the surfactant (polyethylene glycol) that is 0.5% of mixed solution in parts by weight, after stirring Place it in a constant temperature tank and let it stand for 1.5 hours, and the temperature of the constant temperature tank is constant at 45°C;

[0022] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 60 parts by weight of cerium oxide, 40 parts by weight of aluminum oxide;

[0023] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 9, can obtain a kind of colloidal precipitate;

[0024] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0025] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 500°C for 6 hours;

[0026] (5) Grinding the products ...

Embodiment 2

[0029] (1) In the aqueous solution of 150g / L cerium chloride, add aluminum oxide hydrate, make a slurry to obtain the mixed solution, add the surfactant (oleic acid) that is 0.2% of the mixed solution in parts by weight, stir evenly and place it at a constant temperature Stand in the tank for 2 hours, and the temperature of the constant temperature tank is constant at 40°C;

[0030] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 30 parts by weight of cerium oxide, 70 parts by weight of aluminum oxide;

[0031] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 10, can obtain a kind of colloidal precipitate;

[0032] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0033] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 600° C. for 5 hours;

[0034] (5) Grinding the pro...

Embodiment 3

[0037] (1) In the aqueous solution of 170g / L cerium chloride, add aluminum oxide hydrate, make a slurry to obtain the mixed solution, add the surfactant (magnesium phosphate) that is 0.8% of the mixed solution in parts by weight, stir evenly and place it at a constant temperature Stand in the tank for 1 hour, and the temperature of the constant temperature tank is constant at 50°C;

[0038] Wherein, the addition amount of cerium chloride and aluminum oxide hydrate is calculated as oxides: 35 parts by weight of cerium oxide, 65 parts by weight of aluminum oxide;

[0039] (2) ammoniacal liquor or ammonium carbonate are added in the feed liquid after step (1) treatment, control pH value at 8, can obtain a kind of colloidal precipitate;

[0040] (3) washing and dehydrating the colloidal precipitate obtained in step (2) with deionized water;

[0041] (4) putting the product obtained by dehydration in step (3) into a kiln and roasting at 700°C for 4 hours;

[0042] (5) Grinding th...