CN1194813C - Method of preparing SnO2 cladded Tio2 nano particle photocatalyst - Google Patents

Abstract

The invention discloses a method for preparing _SnO2 coated _TiO2 nano particle photocatalyst. The present invention aims to provide a method for preparing _SnO2- coated _TiO2 nanoparticle photocatalyst with low cost and short process cycle. The present invention uses TiOSO ₄ and SnCl ₂ inorganic salts as raw materials, successively uses different concentrations of ammonia water as precipitant, adds non-ionic and anionic polymer dispersants respectively during the precipitation process, and adds appropriate amount of macromolecule surfactant before drying the obtained product , through heat treatment and ball milling to obtain composite powder. The primary particle size of the powder obtained in the present invention is less than 20 nanometers, has good dispersibility, high activity, obvious photocatalytic degradation effect on common organic matter in water and air, has high ultraviolet shielding ability, and can be used for weather-resistant and self-cleaning high-performance nano-coatings The preparation is suitable for preparing nanometer multifunctional ceramic powder.

Description

Method for preparing SnO2 coated TiO2 nanoparticle photocatalyst

Technical field

The invention relates to a method for preparing a nanoparticle photocatalyst, and more specifically relates to a method for preparing a monodisperse, highly active _SnO2- coated _TiO2 nanoparticle photocatalyst by using a step-by-step precipitation method.

Background technique

The preparation of SnO ₂ coated TiO ₂ composite powder usually uses sol-gel process and co-precipitation process. In the sol-gel process, the raw materials are expensive and difficult to obtain; while the particle distribution of the powder obtained by the co-precipitation process is uneven, and the particle size of the powder is wide, which makes the powder activity low.

Contents of Invention

The present invention aims to overcome the deficiencies in the prior art and provide a method for preparing _SnO2- coated _TiO2 nanoparticle photocatalysts with low preparation cost, short process cycle and high product activity.

The present invention is realized through the following technical scheme: add 2-5wt% non-ionic dispersant in distilled water; heat to 38～45 ℃, dropwise add the ammoniacal liquor of TiOSO ₄ and 6N of 0.5-0.8mol/L at the same time, stir Adjust and keep the pH at 4.8-5.5; continue to stir after the dropwise addition and keep warm at 38-45°C for 0.5-1 hour; continue to add 0.5-2.0wt% anionic dispersant to the reaction solution, and drop 0.5- 1.0N ammonia water and 0.5-1.5mol/L SnCl ₂ , adjust the titration rate so that the pH is 4.8-5.5; keep warm at 38-45°C for 1 hour; filter the reaction solution under reduced pressure, and filter the obtained filter cake with deionized Rinse with water; add 2-5wt% macromolecule surfactant to the filter cake; then dry the filter cake at 80-100°C for 3-5 hours; dry-mill the dried product for 0.5-1 hour; Calcining at 380-700°C for 0.5-1 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

The non-ionic dispersant is PEG1000 or PEG1540, the anionic dispersant is PAA1000 or PAA2000, the macromolecular surfactant is O∏-10 or PVA, and the dried product is dry-milled using microparticles ball mill.

The invention has the advantages of novel process, wide sources of raw materials, low product cost, primary powder particle size less than 20 nanometers, good dispersibility, high activity, obvious photocatalytic degradation effect on common organic matter in water and air, and high ultraviolet shielding ability. It can be used in the preparation of weather-resistant and self-cleaning high-performance nano-coatings, and is suitable for preparing nano-functional ceramic powders.

The invention has the advantages of novel process, wide sources of raw materials, low product cost, primary powder particle size less than 20 nanometers, good dispersibility, high activity, obvious photocatalytic degradation effect on common organic matter in water and air, and high ultraviolet shielding ability. It can be used in the preparation of weather-resistant and self-cleaning high-performance nano-coatings, and is suitable for preparing nano-functional ceramic powders.

Figure 1 shows that the main crystal phase of SnO ₂ /TiO ₂ composite particles is rutile at 400°C, and all of them are rutile phase at 700°C; usually pure TiO ₂ needs to be above 750°C to appear rutile phase, while SnO ₂ prepared by other methods /TiO ₂ composite particles generally need to be above 600°C before the rutile phase appears, which fully shows that the powder obtained in the present invention has high activity and the crystal phase transition temperature is lowered by 200-300°C.

It can be clearly seen from Fig. 2 that the powder produced by the present invention has good comprehensive properties, and the particles are not only nanometer, but also uniform in size, that is, the particle size distribution is very narrow.

Description of drawings

Figure 1: XRD pattern of SnO ₂ /TiO ₂ composite particles;

Figure 2: TEM image of SnO ₂ /TiO ₂ composite particles (magnified 100,000 times at 600°C).

Detailed ways

The present invention will be further described below in conjunction with embodiment.

First add 100ml of distilled water into the beaker _, then add 2-5wt% (accounting for TiO 2 in the product SnO ₂ /TiO ₂ ) non-ionic dispersant, heat the temperature bulb to 38-45°C, and drop 0.5-0.8mol/ L of TiOSO ₄ and 6N ammonia water, stir and keep the pH between 4.8 and 5.5, so that TiOSO ₄ is hydrolyzed to form titanium hydrate; Fully done. Add 0.5~2.0wt% (accounting for SnO 2 in the _product SnO ₂ /TiO ₂ ) anionic dispersant dropwise to the reaction solution, then add 0.5~1.0N ammonia water and 0.5~1.5mol/L SnCl ₂ dropwise at the same time to adjust the dropping speed Keep the pH between 4.8 and 5.5, keep it warm at 38 to 45°C for 0.5 to 1 hour after the dropwise addition, keep stirring to make the SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 4 to 7 times, each time with water The amount is about 1/2 of the reaction solution; add 2-5wt% macromolecule surfactant (accounting for the product SnO ₂ /TiO ₂ ) into the filter cake, and then put the filter cake with the active agent under 80-100°C Drying for 3-5 hours; dry-milling the dried product with a particle ball mill for 0.5-1 hour; calcining the dry-milled product at 380-700° C. for 0.5-1 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

The following is an example of preparing _SnO2 coated _TiO2 nanoparticle photocatalyst powder.

Example 1:

Add 100ml of distilled water to the beaker, then add 80mg of dispersant PEG1540, heat the temperature bulb to 40°C, and add 100ml of 0.5mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the pH=5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep warm at 40°C for 0.7 hours to fully complete the reaction. Add 2ml of aqueous solution containing 8mg of dispersant PAA2000 to the reaction solution, and at the same time add dropwise 0.8N ammonia water and 11ml, 0.5mol/L SnCl ₂ , adjust the rate of addition to make PH = 5, and keep the temperature at 40°C for 1 hour after the addition is completed. Stir to make the SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 5 times, each time the water consumption is about 120-130ml; add 96mg of dispersant O∏-10 to the filter cake, and then put the filter cake at 80 dry at 450° C. for 0.8 hours to obtain SnO ₂ -coated TiO ₂ nanoparticle photocatalyst powder.

Example 2:

Add 100ml of distilled water to the beaker, then add 170mg of dispersant PEG1540, heat the temperature bulb to 38°C, add 100ml of 0.7mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the pH = 4.8 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep warm at 38°C for 0.7 hours to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 8mg of dispersant PAA2000 to the reaction solution, then add dropwise 0.5N ammonia water and 15ml, 0.5mol/L SnCl ₂ at the same time, adjust the dropping rate to make PH=4.8, and keep warm at 38°C for 1 hour after the dropwise addition , keep stirring to make SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water 4 times, each water consumption is about 120 ~ 130ml; add 200mg of dispersant PVA to the filter cake, and then filter the cake Drying for 3 hours; dry-milling the dried product for 0.5 hours with a particle ball mill; calcining the dry-milled product at 500° C. for 0.5 hours to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Example 3:

Add 100ml of distilled water into the beaker, then add 280mg of dispersant PEG1000, heat the temperature bulb to 45°C, add 100ml of 0.7mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the pH=5.5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep warm at 45°C for 1 hour to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 17mg of dispersant PAA1000 to the reaction solution, then add dropwise 1.0N ammonia water and 7.5ml, 1.0mol/L SnCl ₂ at the same time, adjust the dropping rate to make pH = 5.5, and keep warm at 45°C for 1 hours, keep stirring to make the SnCl ₂ fully react; filter under reduced pressure, wash 6 times with deionized water, each time the water consumption is about 120 ~ 130ml; add 330mg dispersant O∏-10 to the filter cake, and then filter the cake Dry at 100°C for 3 hours; dry-mill the dried product for 1 hour with a particle ball mill; calcinate the dry-milled product at 500°C for 1 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Example 4:

Add 100ml of distilled water to the beaker, then add 200mg of dispersant PEG1540, heat the temperature bulb to 42°C, add 100ml of 0.8mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the pH = 5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep the temperature at 42° C. for 1 hour to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 17mg of dispersant PAA2000 to the reaction liquid, then add dropwise 0.7N ammonia water and 7ml, 1.2mol/L SnCl ₂ at the same time, adjust the drop rate to make PH=5, and keep warm at 42°C for 1 hour after the dropwise addition , keep stirring to make SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 7 times, each water consumption is about 120-130ml; add 300mg of dispersant O∏-10 to the filter cake, and then filter the cake in Dry at 100°C for 4 hours; dry-mill the dried product for 1 hour with a particle ball mill; calcinate the dry-milled product at 700°C for 0.5 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Example 5:

Add 100ml of distilled water to the beaker, then add 200mg of dispersant PEG1540, heat the temperature bulb to 45°C, and at the same time add 100ml of 0.8mol/L TiOSO ₄ and 6N ammonia water dropwise, stir and keep the pH=5.2 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep the temperature at 40° C. for 0.5 hour to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 20mg of dispersant PAA1000 to the reaction liquid, then add dropwise 1.0N ammonia water and 10.5ml, 0.8mol/L SnCl ₂ at the same time, adjust the rate of addition to make pH = 5.2, and keep warm at 45°C for 1 hours, keep stirring to fully react SnCl ₂ ; filter under reduced pressure, rinse five times with deionized water, each water consumption is about 120 ~ 130ml; add 400mg dispersant PVA to the filter cake, and then put the filter cake at 100 dry at 380° C. for 1 hour to obtain SnO ₂ -coated TiO ₂ nanoparticle photocatalyst powder.

Embodiment 6:

Add 100ml of distilled water to the beaker, then add 200mg of dispersant PEG2000, heat the temperature bulb to 40°C, add 100ml of 0.6mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the PH=5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep warm at 40°C for 0.7 hours to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 12mg of dispersant PAA2000 to the reaction solution, then add dropwise 0.8N ammonia water and 7ml, 0.9mol/L SnCl ₂ at the same time, adjust the drop rate to make PH=5, and keep warm at 40°C for 1 hour after the dropwise addition is completed , keep stirring to make SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 5 times, each water consumption is about 120-130ml; add 170mg dispersant O∏-10 to the filter cake, and then filter the cake in Drying at 80°C for 4 hours; dry-milling the dried product for 0.6 hour with a micrococcus machine; calcining the dry-milled product at 550°C for 0.5-1 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Embodiment 7:

Add 100ml of distilled water to the beaker, then add 200mg of dispersant PEG1000, heat the temperature bulb to 38°C, and add 100ml of 0.5mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep the pH=5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep warm at 40°C for 0.9 hours to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 12mg of dispersant PAA1000 to the reaction liquid, then add dropwise 1.0N ammonia water and 9ml, 0.6mol/L SnCl ₂ at the same time, adjust the drop rate to make PH=5, and keep warm at 42°C for 1 hour after the dropwise addition , keep stirring to make SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 5 times, each water consumption is about 120-130ml; add 170mg dispersant O∏-10 to the filter cake, and then filter the cake in Dry at 80°C for 4.5 hours; dry-mill the dried product for 1 hour with a particle ball mill; calcinate the dry-milled product at 650°C for 0.8 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Embodiment 8:

Add 100ml of distilled water to the beaker, then add 200mg of dispersant PEG1540, heat the temperature bulb to 45°C, add 100ml of 0.7mol/L TiOSO ₄ and 6N ammonia water dropwise at the same time, stir and keep PH = 5 to hydrolyze TiOSO ₄ Titanium hydrate is generated; after the dropwise addition, continue to stir and keep the temperature at 40° C. for 1 hour to fully complete the reaction. Add dropwise 2ml of aqueous solution containing 22mg of dispersant PAA2000 to the reaction solution, then add dropwise 1.0N ammonia water and 5ml, 1.5mol/L SnCl ₂ at the same time, adjust the dropping rate to make PH=5, and keep warm at 45°C for 1 hour after the dropwise addition is completed , keep stirring to make the SnCl ₂ fully react; filter under reduced pressure, rinse with deionized water for 5 times, each time the water consumption is about 120-130ml; add 330mg dispersant O∏-10 to the filter cake, and then filter the cake in Dry at 90°C for 4 hours; dry-mill the dried product for 0.8 hour with a particle ball mill; calcinate the dry-milled product at 600°C for 1 hour to obtain SnO ₂ coated TiO ₂ nanoparticle photocatalyst powder.

Claims (5)

1. one kind prepares SnO ₂Coat TiO ₂The method of nano particle photochemical catalyst is characterized in that, comprises the steps:

(1) non-ionic dispersing agent of adding 2-5wt% in distilled water;

(2) reactant liquor is heated to 38～45 ℃, in this reactant liquor, drips the TiOSO of 0.5-0.8mol/L simultaneously ₄Regulate with the ammoniacal liquor of 6N and keep the pH of this reactant liquor to remain on 4.8～5.5;

(3) dropwising the back continues to stir and be incubated 0.5～1 hour down at 38～45 ℃;

(4) continuation adds the anionic dispersing agent of 0.5～2.0wt% in above-mentioned reactant liquor, drips 0.5～1.0N ammoniacal liquor and 0.5-1.5mol/L SnCl simultaneously ₂, regulate rate of addition and make this reactant liquor pH remain on 4.8～5.5;

(5) 38～45 ℃ of insulations 0.5～1 hour; Reactant liquor is carried out decompress filter, obtain filter cake, and the filter cake that obtains is washed with deionized water;

(6) in above-mentioned filter cake, add the 2-5wt% molecules surfactant; The filter cake that will have activating agent then descended dry 3-5 hour at 80～100 ℃;

(7) product of drying was dry grinded 0.5～1 hour;

(8) product of will dry grinding was calcined 0.5～1 hour at 380～700 ℃, obtained SnO ₂Coat TiO ₂Nano particle photochemical catalyst powder.

2. preparation SnO according to claim 1 ₂Coat TiO ₂The method of nano particle photochemical catalyst is characterized in that, described non-ionic dispersing agent is PEG1000 or PEG1540.

3. preparation SnO according to claim 1 ₂Coat TiO ₂The method of nano particle photochemical catalyst is characterized in that, described anionic dispersing agent is PAA1000 or PAA2000.

4. preparation SnO according to claim 1 ₂Coat TiO ₂The method of nano particle photochemical catalyst is characterized in that, described molecules surfactant is O ∏-10 or PVA.

5. preparation SnO according to claim 1 ₂Coat TiO ₂The method of nano particle photochemical catalyst is characterized in that, the particle sphere grinding machine is used in described dry grinding.