CN1095487C - Active oxide coated porous powder and its preparing process and application - Google Patents

Abstract

The invention relates to a highly active oxide-coated porous powder, a preparation method and application. The powder includes nano-scale titanium dioxide or aluminum oxide or chromium oxide or nickel oxide or iron oxide, or a mixture of two or more of these substances in any weight ratio of 25% to 65%; alkaline earth metal oxide 5% to 60%; silicide and/or boride and/or rare earth oxide 5% to 45%. The preparation method is to prepare the above components, water, high molecular polymer and acid into a homogenized slurry and then further process it. The powder is used to make ambient air purification, self-cleaning, deodorizing, antibacterial and antifouling coatings, as well as inks with photocatalytic properties and filler additives for printable coatings. The dispersibility, durability and weather resistance of the powder are all improved and enhanced.

Description

Active oxide-coated porous powder material and its preparation method and use

The invention belongs to the technical field of nano inorganic powder materials, and in particular relates to porous powder materials coated with highly active oxides, especially powder materials coated with nanoscale TiO ₂ and its preparation method and application.

So far, powder materials coated with titanium dioxide can not only be coated on the surface of paper, plastic, wood and metal to play a pearlescent or shading effect, but also because of its small particle size, large specific surface, and air, making it The density is reduced, and when it is combined with some special additives, the function of the coating (such as photocatalytic activity) will be brought into play beyond the conventional.

The disclosed coated nano-scale oxide powder is usually prepared into a fine powder by wet chemical methods such as coprecipitation method, emulsion method and hydrothermal method, and then undergoes emulsion polymerization method, interface polymerization method, simple coagulation method, etc. Fine coated microcapsule powder materials can be prepared by the method and drying bath method. These coated powder materials have high activity and large specific surface, but they also have the disadvantages of easily adsorbing gas and liquid, and making the powder easy to agglomerate, which makes it difficult to exert its proper performance. For reports in this regard, see the article on page 50 of the 19th issue of the 19th issue of the "Modern Chemical Industry" magazine in 1999 and the article on the 18th-20th page of the 5th issue of the 1999 volume 5 of the "China Powder Technology" magazine.

The purpose of the present invention is to overcome the shortcomings of the above-mentioned technologies, and provide a porous powder material coated with a highly active oxide, especially a powder material coated with nanoscale TiO ₂ and its preparation method and application. This oxide-coated powder material has improved dispersion, durability, and weather resistance due to its special surface morphology, thereby increasing its surface activity and endowing its surface with new physical, chemical, and optical properties. To adapt to different application requirements, thereby greatly improving the added value of powder materials prepared by this technology.

The purpose of the present invention is achieved like this:

The porous powder coated with highly active oxides provided by the present invention has a composition (percentage by weight) containing:

Nanoscale titanium dioxide; or a mixture of nanoscale titanium dioxide and one, two or more selected from nanoscale alumina, nanoscale chromium trioxide, nanoscale nickel oxide and nanoscale iron oxide in any weight ratio: 25% to 65%;

Alkaline earth metal oxides: 5% to 60%;

Silicide; or a mixture of silicide, boride and/or rare earth oxide, wherein the silicide accounts for more than half of the weight of the mixture: 5% to 45%. Among them, alkaline earth metal oxides are BaO, CaO or MgO, etc.; silicides are SiO ₂ or Na ₂ SiO ₃ , etc.; borides are B ₂ O ₃ , H ₃ BO ₃ or Na ₂ B ₄ O ₇ , etc.; rare earth oxides are La ₂ O ₃ or CeO ₂ etc.

The preparation method of the porous powder coated with highly active oxides provided by the present invention is carried out in the following steps:

First add one, two or more of nanoscale titanium dioxide, nanoscale alumina, nanoscale chromium trioxide, nanoscale nickel oxide and nanoscale iron oxide with a weight percentage of 10% to 25%. The mixture mixed in weight ratio, alkaline earth metal oxide with a weight percentage of 10% to 30% and water with a weight percentage of 40% to 65% is stirred evenly; silicides and borides and/or rare earth oxides (wherein the silicides account for more than half of the weight of the mixture), the weight percentage is 0.1% to 5% of water-soluble high molecular polymers, and the weight percentage is 0 to 10 % of inorganic acid or organic acid, fully stirred at 50-90°C, and ground for more than 1 hour to form a fine homogeneous slurry, wherein the grinding medium is zirconia pellets; then the fine homogeneous slurry is Processed into granular powder; then sintered at a high temperature of 500°C to 1200°C for 0.01 to 3 minutes to obtain a porous powder carrier; then put the sintered porous powder carrier into the oxide-containing aqueous suspension for coating , fully stirred for 10 minutes to 30 minutes and then dried or sintered at a high temperature of 500°C to 1200°C to obtain a porous powder material coated with a highly active oxide;

Wherein the composition and weight percent content of the oxide-containing aqueous suspension for coating are:

  Nano-scale titanium dioxide 2% to 10%;

Titanium compound 0～15%;

Soluble alkaline earth metal salt 5% to 30%;

                                   

Silicide 0～10%;

Water 65% to 90%.

in

The alkaline earth metal oxides in the fine homogeneous slurry are BaO, CaO or MgO, etc.; the silicides are SiO ₂ or Na ₂ SiO ₃ , etc.; the borides are B ₂ O ₃ , H ₃ BO ₃ or Na ₂ B ₄ O _7, etc.; rare earth oxides are La ₂ O ₃ or CeO _2, etc.; water-soluble polymers are polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyethylene oxide (PEO), methyl cellulose ( MC), carboxymethyl cellulose (CMC) or carboxyethyl cellulose (EC); the inorganic acid or organic acid is hydrochloric acid, nitric acid, acetic acid or oxalic acid and the like.

The conventional drying process is air drying, spray drying or boiling drying.

The soluble alkaline earth metal salt in the oxide-containing aqueous suspension for coating is barium nitrate, magnesium nitrate, calcium chloride or magnesium chloride; the titanium compound is n-butyl titanate; the boride is Boric acid; the silicide is silicic acid or fumed silica.

Uses of the present invention: The highly active oxide-coated porous powder provided by the present invention can be used to make environmental air purification, self-cleaning, deodorizing, antibacterial and anti-fouling coatings and a series of special inks and inks with photocatalytic properties. Filler additive for printable coatings.

The advantages of the present invention: the oxide-coated powder material of the present invention, due to the special shape of its surface, its dispersibility, durability, and weather resistance are improved and improved, and its surface activity is further improved, so that its surface is endowed with new The physical, chemical, and optical properties of the powder can be adapted to different application requirements, thereby greatly increasing the added value of the powder material produced by this technology.

The present invention is described in detail below in conjunction with examples: but described embodiment is in no way limiting protection scope of the present invention.

Example 1:

Nano Titanium Dioxide 20% (weight)

BaO 20% (weight)

SiO ₂ 5% (weight)

Polyvinyl alcohol (PVA) 2% (weight)

Water 50% (by weight)

Hydrochloric acid 3% (weight)

First add nano-scale titanium dioxide, BaO and water according to the above ratio, stir evenly, then add SiO ₂ , polyvinyl alcohol (PVA), hydrochloric acid, stir thoroughly at 50°C, and grind for 3 hours to a fine homogeneous slurry, in which the grinding medium Zirconium dioxide pellets. Then air drying is used to process the fine homogeneous slurry into particle powder with an average particle size of 25 μm. Then sinter at a high temperature of 500°C for 3 minutes to obtain a porous powder carrier. Then put the sintered porous powder carrier into an aqueous solution of 5% titanium dioxide and 10% barium nitrate by weight, stir thoroughly for 30 minutes, then dry and sinter at 500°C to obtain an average particle size of 26μm highly reactive oxide coated porous powder material. The components and weight percentages are: 50% of nano titanium dioxide; 40% of BaO; 10% of SiO ₂ .

Example 2

Nanoscale alumina 23% (weight)

CaO 20% (weight)

SiO ₂ and B ₂ O ₃ 5% (weight)

Wherein the weight ratio of SiO ₂ and B ₂ O ₃ is 3:2

Polyethylene oxide (PEO) 0.2% (weight)

Water 50% (weight)

Inorganic acid or organic acid 1.8% (weight)

First add nano-scale alumina, CaO and water according to the above ratio, stir evenly, then add other components, stir thoroughly at 60°C, and grind for 2 hours to form a fine homogeneous slurry, wherein the grinding medium is zirconia pellets. Then the slurry is spray-dried under the condition of 115° C., and the fine homogeneous slurry is processed into a particle powder with an average particle diameter of 30 μm. Then sinter at a high temperature of 800°C for 2 minutes to obtain a porous powder carrier. Then put the sintered porous powder carrier into the homogeneous aqueous solution containing 3% by weight of nano-scale titanium dioxide and 5% by weight of calcium chloride, stir thoroughly for 10 minutes and then dry at 120°C A highly active oxide-coated porous powder material with a diameter of 30.5 μm can be obtained; the components and weight percentages are: nano-scale titanium dioxide 5.9%, nano-scale alumina 45.1%, CaO 39.2%, SiO ₂ and _{B2O3 9.8} %.

Example 3

Nanoscale Chromium Trioxide 25% (weight)

MgO 15% by weight

Na ₂ SiO ₃ 5% (weight)

Polyethylene glycol (PEG) 1% (by weight)

Water 54% (weight)

First add nano-scale chromium trioxide, MgO and water according to the above ratio, stir evenly, then add Na ₂ SiO ₃ and polyethylene glycol (PEG), stir thoroughly at 80°C, and grind for 1.5 hours to form a fine homogeneous slurry , wherein the grinding medium is zirconia pellets. Then the slurry is spray-dried under the condition of 120° C., and the fine homogeneous slurry is processed into a particle powder with an average particle diameter of 20 μm. Then sinter at a high temperature of 1000°C for 1 minute to obtain a porous powder carrier. Then the porous powder carrier after the sintering is dropped into the aqueous solution containing 6% (weight percentage) of nano-scale titanium dioxide, 5% (weight percentage) of magnesium chloride and 5% (weight percentage) of boric acid and through homogeneous treatment, fully stirred for 20 minutes After drying at 120° C., a highly active oxide-coated porous powder material with an average particle size of 21 μm can be obtained. The components and weight percentages are: nanoscale titanium dioxide 11.8%, nanoscale chromium trioxide 49.0%, MgO 29.4%, Na ₂ SiO ₃ 9.8%.

Example 4

Nano-scale nickel oxide 20% (weight)

BaO 15% by weight

Na ₂ SiO ₃ , La ₂ O ₃ and Na ₂ B ₄ O ₇ , 10% by weight

Its weight ratio is Na ₂ SiO ₃ : La ₂ O ₃ : _{Na 2} B ₄ O ₇ =3:1:1;

Carboxymethylcellulose (CMC) 2% (weight)

Water 53% (weight)

First add nano-scale nickel oxide, BaO and water according to the above ratio, stir evenly, then add Na ₂ SiO ₃ , La ₂ O ₃ , Na ₂ B ₄ O ₇ , carboxymethyl cellulose (CMC) and acetic acid, at 90 After fully stirring at ℃, grind for 3 hours to form a fine homogeneous slurry, wherein the grinding medium is zirconium dioxide pellets. Then the slurry is spray-dried under the condition of 120° C., and the fine homogeneous slurry is processed into a particle powder with an average particle diameter of 30 μm. Then sinter at a high temperature of 1200° C. for 0.02 minutes to obtain a porous powder carrier. Then put the sintered porous powder carrier into the homogeneously treated aqueous solution containing 10% (weight percent) of nano-scale titanium dioxide, 15% (weight percent) of barium nitrate and 5% (weight percent) of silicic acid, and fully stir After 30 minutes, dry at 120°C to obtain a highly active oxide-coated porous powder material with an average particle size of 30 μm. The components and weight percentages are: nanoscale titanium dioxide 18.2%, nanoscale nickel oxide 36.4% %, BaO 27.3%, Na ₂ SiO ₃ , and La ₂ O ₃ , Na ₂ B ₄ O ₇ 18.1%.

Example 5

Nanoscale iron oxide 20% (weight)

CaO 20% (weight)

SiO ₂ 5% (weight)

Carboxyethyl cellulose (EC) 2% (weight)

Water 51% (weight)

Nitric acid 2% (weight)

First add nanoscale iron oxide, CaO and water according to the above ratio, stir evenly, then add SiO ₂ , polycarboxyethyl cellulose (EC) and nitric acid, fully stir at 70°C, and grind for 4 hours to form a fine homogeneous slurry , wherein the grinding medium is zirconia pellets. Then the slurry is spray-dried under the condition of 120° C., and the fine homogeneous slurry is processed into a particle powder with an average particle diameter of 8 μm. Then sinter at 900°C for 1 minute to obtain a porous powder carrier. Then the porous powder carrier after the sintering is dropped into containing nanoscale titanium dioxide 10% (weight percent), n-butyl titanate 3% (weight percent), magnesium chloride 10% (weight percent), boric acid 5% (weight percent) and Silicic acid 2% (weight percent) and homogeneously treated aqueous solution, fully stirred for 30 minutes and then dried at 120 ° C to obtain a highly active oxide-coated porous powder material with a particle size of 9 μm in diameter. The components and weight percentages are: 18.2% of nanoscale titanium dioxide, 36.4% of nanoscale iron oxide, 36.4% of CaO, and 9.1% of SiO ₂ .

Example 6

A mixture of nanoscale titanium dioxide and aluminum oxide and nickel oxide, wherein titanium dioxide is 10% by weight,

Aluminum oxide is 5% (weight) Nickel oxide is 3% (weight) 18% (weight)

BaO 20% (weight)

SiO ₂ 5% (weight)

Carboxymethylcellulose (CMC) 2% (weight)

Water 53% (weight)

Hydrochloric acid 2% (weight)

First add the mixture of nano-scale titanium dioxide, aluminum oxide and nickel oxide, BaO and water according to the above ratio, stir evenly, then add SiO ₂ , carboxymethyl cellulose (CMC) and hydrochloric acid, stir thoroughly at 90°C, and grind for 3 Hours into a fine homogeneous slurry, in which the grinding medium is zirconia pellets. Then the slurry is spray-dried under the condition of 120° C., and the fine homogeneous slurry is processed into a particle powder with an average particle diameter of 35 μm. Then sinter at a high temperature of 1200° C. for 0.02 minutes to obtain a porous powder carrier. Then put the sintered porous powder carrier into the homogeneously treated aqueous solution containing 10% (weight percent) of nano-scale titanium dioxide, 5% (weight percent) of barium nitrate and 5% (weight percent) of silicic acid, and fully stir After 30 minutes, dry at 120°C to obtain a highly active oxide-coated porous powder material with an average particle size of 36 μm. The components and weight percentages are: a mixture of nano-scale titanium dioxide, alumina and nickel oxide 52.8%, BaO 37.7%, SiO ₂ 9.4%.

Claims (5)

1. the porous powder material that coats of an activating oxide is characterized in that comprising that following component and weight percentage are:

Nano titanium dioxide; Or Nano titanium dioxide and be selected from a kind of in alumina in Nano level, nano level chromium sesquioxide, nano level nickel oxide and the nanometer ferro oxide, two or more mixture of forming by any part by weight: 25%～65%;

Alkaline earth metal oxide BaO, CaO or MgO:5%～60%;

Silicide SiO ₂Or Na ₂SiO ₃Or silicide SiO ₂Or Na ₂SiO ₃With boride B ₂O ₃, H ₃BO ₃Or Na ₂B ₄O ₇And/or rare earth oxide La ₂O ₃Or CeO ₂The mixture of forming, wherein silicide accounts for weight over half:

5％～45％；

Its preparation method is:

Add earlier weight percent and be 10%～25% be selected from a kind of in Nano titanium dioxide, alumina in Nano level, nano level chromium sesquioxide, nano level nickel oxide and the nanometer ferro oxide, two or more is that 10%～30% alkaline earth metal oxide BaO, CaO or MgO and weight percent are 40%～65% water by any part by weight blended mixture, weight percent, stir; Add weight percent again and be 0.5%～10% silicide SiO ₂Or Na ₂SiO ₃, or silicide SiO ₂Or Na ₂SiO ₃With boride B ₂O ₃, H ₃BO ₃Or Na ₂B ₄O ₇And/or rare earth oxide La ₂O ₃Or CeO ₂The mixture of forming, over half, the weight percent that wherein said silicide accounts for mixture weight is that 0.1%～5% high molecular weight water soluble polymer, weight percent are 0～10% mineral acid or organic acid, stir through abundant down at 50～90 ℃, grinding becomes meticulous homogeneous slurry more than 1 hour, wherein grinding medium is the zirconium dioxide bead; Adopt conventional drying process then, meticulous homogeneous slurry is processed into granular powder; Through 500 ℃ to 1200 ℃ high temperature sinterings 0.01～3 minute, promptly obtain the porous powder carrier then; Then the porous powder carrier behind the sintering is put in the oxidiferous aqeous suspension that coats usefulness, fully stir after 10 minutes～30 minutes again drying or handle, can obtain the porous powder material that high activity oxide coats through 500 ℃～1200 ℃ high temperature sinterings;

The component of the oxidiferous aqeous suspension of wherein said coating usefulness and weight percent content are:

Nano titanium dioxide 2%～10%;

The positive factory of metatitanic acid ester 0～15%;

Soluble alkaline earth salt 5%～30%;

Boric acid 0～10%;

Silicic acid or aerosil 0～10%;

Water 65%～90%.

2. the porous powder material that activating oxide as claimed in claim 1 coats, the drying process that it is characterized in that described routine is air stream drying, spraying drying or fluidized drying.

3. the porous powder material that activating oxide as claimed in claim 1 coats is characterized in that described high molecular weight water soluble polymer is polyvinyl alcohol, polyoxyethylene glycol, polyoxyethylene, methylcellulose gum, carboxymethyl cellulose or carboxyethyl cellulose.

4. the porous powder material that activating oxide as claimed in claim 1 coats is characterized in that the soluble alkaline earth salt in the oxidiferous aqeous suspension of described coating usefulness is nitrate of baryta, magnesium nitrate, calcium chloride or magnesium chloride.

5. the purposes of a porous powder material that coats as any described activating oxide of claim 1-4, but it is characterized in that being used for production environment purifying air, self-cleaning, deodorization, antibiotic and the coating of antiscale and printing ink and printing coatings with a series of special uses of photocatalysis characteristic.