CN1213659A - Superfine titanium white surface cladding tech. and reactor thereof - Google Patents

Superfine titanium white surface cladding tech. and reactor thereof Download PDF

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Publication number
CN1213659A
CN1213659A CN 98117967 CN98117967A CN1213659A CN 1213659 A CN1213659 A CN 1213659A CN 98117967 CN98117967 CN 98117967 CN 98117967 A CN98117967 A CN 98117967A CN 1213659 A CN1213659 A CN 1213659A
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reactor
value
nozzle
exit end
titanium white
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CN1067967C (en
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崔爱莉
王亭杰
金涌
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Tsinghua University
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Tsinghua University
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
    • C04B20/10—Coating or impregnating
    • C04B20/1055—Coating or impregnating with inorganic materials
    • C04B20/1066—Oxides, Hydroxides

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)

Abstract

A surface coating process for ultrafine titanium oxide powder includes adding disperser to TiO2 milk, heating to a certain temp, addition of sodium silicate, regulating pH value with diluted sulfuric acid, keeping the temp constant, ageing, addition of sodium hydroxide, regulating pH value, addition of aluminium sulfate, regulating pH value, filter, washing in water, and drying. Its reactor has nozzles on side wall and material inlet and outlet. With the process, uniform and compact inorganic film is formed to wrap the titanium oxide particles for lower thioxotropy and higher powdering resistance and weatherability.

Description

Superfine titanium white surface cladding tech and reactor thereof
The present invention relates to a kind of superfine titanium white surface cladding tech and reactor thereof, belong to the material technology field.
The superfine titanic oxide particle grain size is generally 0.2～0.4 μ m.On the one hand, because the particle small specific surface is long-pending big, intergranular cohesive force strengthens, and particle is easily reunited, the dispersed reduction in resin.Therefore, before surface treatment, must make TiO 2The particle of reuniting in the slurries is dispersed into single particle.At present, domestic main dispersing apparatus is a ball mill, and there is following shortcoming in this dispersing method: 1, ball mill is owing to existing back-mixing, so the material particles size-grade distribution that grinds is wide, does not reach monodispersed requirement.2, ball mill is the method for inner dress sand grains mechanical friction, because sand grains and material (TiO 2) contact friction, can bring pollution, reduce TiO 2Purity.3, at present domestic ball mill power consumption is big, the cost height.On the other hand, if TiO 2Particle directly joins in coating, the paint and goes, and then exists weathering resistance poor, and resistance to chalking hangs down and waits detrimentally affect.Therefore; the purpose that inorganic coating is handled is to coat layer protecting film on the surface of titanium dioxide; make and set up barrier together between titanium dioxide surface and the surrounding medium; thereby reduce the photochemical activity of titanium dioxide, help improving dispersiveness, photostabilization, weathering resistance and the resistance to chalking of titanium dioxide.
Existing about TiO in United States Patent (USP) 3437502 2The report of coating method, its coating equipment are common stirring tanks, because the restriction of appointed condition and technology, the coating effect is bad, and coating is inhomogeneous, and independently SiO is arranged 2And Al 2O 3Particle self nucleation, the thixotropy that shows as product in the specific implementation process is big, and sad filter is with dried machine throughput to reduce, and causes every performance index of finished product not reach requirement.
The objective of the invention is to develop a kind of superfine titanium white surface cladding tech and reactor thereof, under the so-gel theoretical direction, the evenly technology of bag silicon, alclad is proposed, and match with novel high field of turbulent flow coating device, make particle list dispersion process and film process integrated, and making whole technological operation easy, energy consumption is low, and is easy to the engineering amplification.The finished product thixotropy is low, and film forming is even.
The superfine titanium white surface cladding tech of the present invention's development comprises following each step:
(1) in the aqueous slurry that contains 10～30% titanium dioxide, adds dispersion agent Na 2SiO 3, the pH value that makes solution is 8.0～9.0, stir about 15～20 minutes carries out pre-dispersed;
(2) above-mentioned solution is heated to 80 ℃～90 ℃, adds the water glass of 0.1～0.5mol/l, the stoichiometry that adds water glass is SiO 2: TiO 2=0.01～0.02: 1, the pH value of the dilute sulphuric acid regulator solution with 10～20% is 7.0～8.0, is incubated 3～4 hours down at 80 ℃～90 ℃, ageing;
(3) on the basis of the above-mentioned second step bag silicon fiml, make solution temperature remain on 70 ℃～80 ℃, add 0.1mol/l Tai-Ace S 150, adding the Tai-Ace S 150 stoichiometry is Al 2O 3: TiO 2=0.02～0.04: 1, use 0.1mol/l sodium hydroxide, the pH value of regulator solution is 6～7, stirs 10 minutes;
(4) transferring the pH value of above-mentioned slurries with 0.1mol/l～0.2mol/l Tai-Ace S 150 is 7.0, continues to stir 2～3 hours, filters, be washed to barium salt check sulfate radical-free ion, at last, drying is 4～5 hours under 110 ℃～120 ℃, promptly obtains the superfine titanium white with silicon oxide and aluminum oxide coating.
The present invention has designed the reactor that is specifically designed to the above-mentioned superfine titanium white of preparation, the top of reactor is provided with opening for feed, the bottom is provided with discharge port, on the two side of reactor nozzle is housed, the entrance end of nozzle is taper, and exit end is a cylindricality, and the top opening for feed communicates with the exit end of nozzle, the opening for feed cone angle of nozzle is 13 °～14 °, exit end diameter d and exit end body length L 1Ratio be d: L 1=1: 2.5～3, exit end column length L 1With the long L of entrance end awl 2Ratio be L 1: L 2=1: 2～4.
The cladding process that the present invention proposes coats layer protecting film on the surface of titanium dioxide, makes between the surperficial of titanium dioxide and its medium on every side and sets up barrier together, thereby reduce the photochemical activity of titanium dioxide.Wrap one deck Al again 2O 3Behind the film, form the silicon-aluminium binary coating, and this technology has realized the film forming coating and nuclear envelope do not occurred into.
The present invention has also designed special-purpose reactor, the reactor content import is designed to form of nozzle,, pressure can be gathered together by the contraction of nozzle endoporus cross section, and be converted into kinetic energy, form with high-speed jet outwards sprays at last, in order to material is disperseed or fragmentation, to generate even, fine and close mineral membrane, and control thickness, reduce the thixotropy of product, easily filter, thereby improved resistance to chalking and the weathering resistance of titanium dioxide in paint greatly.
Description of drawings:
Fig. 1 is the structural representation of the reactor that designs of the present invention.
Fig. 2 (a) and (b), (c), (d) prepare the electromicroscopic photograph of sample for the present invention.
Below in conjunction with accompanying drawing, introduce in detail content of the present invention.
Among Fig. 1, the 1st, reactor, 2 and 5 is nozzles, 3 and 4 is charging apertures, the 6th, discharging opening.
As shown in Figure 1, the present invention has designed the reactor that is specifically designed to the above-mentioned superfine titanium white of preparation, the top of reactor is provided with charging aperture 3 and 4, the bottom is provided with discharging opening 6, and nozzle 2 and 5 are housed on the two side of reactor, and the entrance point of nozzle is taper, the port of export is cylindricality, the top charging aperture communicates with the port of export of nozzle, and the charging aperture cone angle of nozzle is 13 °～14 °, port of export diameter d and port of export body length L1Ratio be d: L1=1: 2.5～3, port of export column length L1With the long L of entrance point cone2Ratio be L1∶L 2=1: 2～4. The mechanism of reactor is to utilize the high field of turbulent flow of nozzle 2 and 5, and the coating agent is being become Can carry out fast microcosmic before the film and mix, produce a uniform CONCENTRATION DISTRIBUTION, then equably at TiO2Superficial growth. Thing Material TiO2And H2From 2,5 pairs of sprays of nozzle, film forming agent (is Na during bag silicon to O simultaneously with pump2SiO 3And H2SO 4, be NaOH and Al during alclad2(SO 4) 3) enter spray nozzle front end through charging aperture 3,4 respectively and enter together reactor. Mixed in impact cavity Change aging tank over to from discharging opening 6 after closing, carry out next step work.
Introduce embodiments of the invention below.
Embodiment 1 adds the dispersion agent water glass in the slurries that contain 15% titanium dioxide, the pH value to 8 of regulator solution, and stirring is carried out pre-dispersed, is heated to 85 ℃, and the stoichiometry of water glass is controlled at SiO 2/ TiO 2=2%, with the pH value to 8 that 10% dilute sulphuric acid is transferred solution, the bag silicon fiml is finished in ageing.On the basis of bag silicon fiml, holding temperature adds the Tai-Ace S 150 of 0.1mol/l and 20% sodium hydroxide simultaneously at 80 ℃, and the stoichiometry of Tai-Ace S 150 is controlled at Al 2O 3/ TiO 2=2%, use the sodium hydroxide adjust pH, maintain pH=8, with the pH to 7.0 of Tai-Ace S 150 adjusting slurry, ageing is washed to no SO 4 2-,, obtain the titanium dioxide of silicon-aluminium binary coating with barium salt check, filtration, 120 ℃ of dryings.The gained sample is even, fine and close film.The TEM photo is seen Fig. 4 (a), surface composition analysis in table 1.
Embodiment 2 experimental techniques are with implementing 1.Change the acidity of bag silicon fiml, the pH to 8.5 of regulator solution carries out pre-dispersed, and wraps silicon fiml under this acidity.The gained sample is the loose membrane of sponge shape, and the TEM photo is seen Fig. 4 (b), surface composition analysis in table 1.
Embodiment 3 experimental techniques are with embodiment 1.Change over the acid degree.Wrap silicon fiml under the pH=7 condition during bag silicon fiml.The gained sample is that nucleation coats, rather than film forming coats.The TEM photo is seen Fig. 4 (c), surface composition analytical table 1.
Embodiment 4 experimental techniques are with embodiment 1.Change over the consumption of film.SiO2/TiO2=1～1.6%, Al 2O 3/ TiO 2The TEM of=2% gained sample sees Fig. 4 (d), surface composition analysis in table 1.

Claims (2)

1, a kind of superfine titanium white surface cladding tech is characterized in that, this technology comprises following each step:
(1) in the aqueous slurry that contains 10～30% titanium dioxide, adds dispersion agent Na 2SiO 3, the pH value that makes solution is 8.0～9.0, stir about 15～20 minutes carries out pre-dispersed;
(2) above-mentioned solution is heated to 80 ℃～90 ℃, adds the water glass of 0.1～0.5mol/l, the stoichiometry that adds water glass is SiO 2: TiO 2=0.01～0.02: 1, the pH value of the dilute sulphuric acid regulator solution with 10～20% is 7.0～8.0, is incubated 3～4 hours down at 80 ℃～90 ℃, ageing;
(3) on the basis of the above-mentioned second step bag silicon fiml, make solution temperature remain on 70 ℃～80 ℃, add 0.1mol/l Tai-Ace S 150, adding the Tai-Ace S 150 stoichiometry is Al 2O 3: TiO 2=0.02～0.04: 1, use 0.1mol/l sodium hydroxide, the pH value of regulator solution is 6～7, stirs 10 minutes;
(4) transferring the pH value of above-mentioned slurries with 0.1mol/l～0.2mol/l Tai-Ace S 150 is 7.0, continues to stir 2～3 hours, filters, be washed to barium salt check sulfate radical-free ion, at last, drying is 4～5 hours under 110 ℃～120 ℃, promptly obtains the superfine titanium white with silicon oxide and aluminum oxide coating.
2, a kind of reactor that is used to prepare above-mentioned superfine titanium white, it is characterized in that, the top of this reactor is provided with opening for feed, the bottom is provided with discharge port, on the two side of reactor nozzle is housed, and the entrance end of nozzle is taper, exit end is a cylindricality, the top opening for feed communicates with the exit end of nozzle, and the opening for feed cone angle of nozzle is 13 °～14 °, exit end diameter d and exit end body length L 1Ratio be d: L 1=1: 2.5～3, exit end column length L 1With the long L of entrance end awl 2Ratio be L 1: L 2=1: 2～4.
CN98117967A 1998-09-11 1998-09-11 Superfine titanium white surface cladding tech. and reactor thereof Expired - Fee Related CN1067967C (en)

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Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100439454C (en) * 2006-12-20 2008-12-03 中国科学院山西煤炭化学研究所 Titanium dioxide surface organic-inorganic modification method
CN100506922C (en) * 2006-05-18 2009-07-01 攀钢集团攀枝花钢铁研究院 Method for producing high covering power titanium dioxide pigment
CN100506923C (en) * 2006-05-18 2009-07-01 攀钢集团攀枝花钢铁研究院 Method for producing high weathering resistance titanium dioxide pigment
CN100999621B (en) * 2006-12-20 2010-09-01 中国科学院山西煤炭化学研究所 Process for inorganic-organic coating on surface of titanium white powder
CN1806018B (en) * 2003-07-18 2010-10-06 克罗内斯国际公司 Method for treating the surface of a titanium dioxide pigment
CN102093758A (en) * 2009-12-10 2011-06-15 湖南金马硅业有限公司 Artificial composite pigment and preparation method thereof
CN102199367A (en) * 2011-03-30 2011-09-28 中国科学院宁波材料技术与工程研究所 Method for preparing titanium dioxide pigment with high-temperature resistance
CN103913431A (en) * 2014-04-21 2014-07-09 济南裕兴化工有限责任公司 Method for measuring acid solubility of titanium dioxide
CN104479417A (en) * 2014-12-23 2015-04-01 安徽助成信息科技有限公司 Preparation method of rutile titanium dioxide inorganic coating film
CN105013600A (en) * 2015-07-03 2015-11-04 攀钢集团钛业有限责任公司 Device used for continuously separating coarse grains before coating process of titanium dioxide
CN105293991A (en) * 2015-10-16 2016-02-03 卓达新材料科技集团威海股份有限公司 Modifying agent for filler and preparation method of filler
CN105860592A (en) * 2016-05-05 2016-08-17 中钛集团洛阳市裕星化工有限公司 Modified titanium dioxide powder with coated polyacrylic acid
CN105968652A (en) * 2016-07-20 2016-09-28 广州市恒德环保材料有限公司 PVC compound material
CN108635241A (en) * 2018-06-07 2018-10-12 上海蔻沣生物科技有限公司 One kind having thixotropic oiliness slurry and preparation method thereof
CN110451835A (en) * 2019-09-17 2019-11-15 安徽好思家涂料股份有限公司 A kind of artificial color sand of high abrasion low-temperature sintering and preparation method thereof
CN113881227A (en) * 2021-11-20 2022-01-04 彩虹高新材料（莱阳）有限公司 Ultraviolet-resistant polyether sulfone resin and preparation method thereof
CN114507080A (en) * 2022-02-17 2022-05-17 广东欧文莱陶瓷有限公司 High-toughness ceramic sheet and preparation method thereof
CN115851000A (en) * 2022-12-06 2023-03-28 龙佰禄丰钛业有限公司 Method and device for drying titanium dioxide filter cake by contact change promotion

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3437502A (en) * 1968-03-28 1969-04-08 Du Pont Titanium dioxide pigment coated with silica and alumina
CN1008356B (en) * 1985-04-30 1990-06-13 河南师范大学 Preparation of rutile type pigment titanium white by high activity crystal
CN86101534A (en) * 1986-08-07 1988-02-17 上海京华化工厂 The preparation method of water dispersing lide powder pigment
CN1054780C (en) * 1994-10-20 2000-07-26 中国科学院山西煤炭化学研究所 Method of preparing coated superfine powder with metal surfactant by phase transfer

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CN1806018B (en) * 2003-07-18 2010-10-06 克罗内斯国际公司 Method for treating the surface of a titanium dioxide pigment
CN100506922C (en) * 2006-05-18 2009-07-01 攀钢集团攀枝花钢铁研究院 Method for producing high covering power titanium dioxide pigment
CN100506923C (en) * 2006-05-18 2009-07-01 攀钢集团攀枝花钢铁研究院 Method for producing high weathering resistance titanium dioxide pigment
CN100439454C (en) * 2006-12-20 2008-12-03 中国科学院山西煤炭化学研究所 Titanium dioxide surface organic-inorganic modification method
CN100999621B (en) * 2006-12-20 2010-09-01 中国科学院山西煤炭化学研究所 Process for inorganic-organic coating on surface of titanium white powder
CN102093758A (en) * 2009-12-10 2011-06-15 湖南金马硅业有限公司 Artificial composite pigment and preparation method thereof
CN102093758B (en) * 2009-12-10 2014-01-01 湖南金马硅业有限公司 Artificial composite pigment and preparation method thereof
CN102199367A (en) * 2011-03-30 2011-09-28 中国科学院宁波材料技术与工程研究所 Method for preparing titanium dioxide pigment with high-temperature resistance
CN103913431A (en) * 2014-04-21 2014-07-09 济南裕兴化工有限责任公司 Method for measuring acid solubility of titanium dioxide
CN104479417A (en) * 2014-12-23 2015-04-01 安徽助成信息科技有限公司 Preparation method of rutile titanium dioxide inorganic coating film
CN105013600A (en) * 2015-07-03 2015-11-04 攀钢集团钛业有限责任公司 Device used for continuously separating coarse grains before coating process of titanium dioxide
CN105293991A (en) * 2015-10-16 2016-02-03 卓达新材料科技集团威海股份有限公司 Modifying agent for filler and preparation method of filler
CN105860592A (en) * 2016-05-05 2016-08-17 中钛集团洛阳市裕星化工有限公司 Modified titanium dioxide powder with coated polyacrylic acid
CN105860592B (en) * 2016-05-05 2018-02-16 焦作市裕盛钛业有限公司 A kind of modified titanium for being coated with polyacrylic acid
CN105968652A (en) * 2016-07-20 2016-09-28 广州市恒德环保材料有限公司 PVC compound material
CN105968652B (en) * 2016-07-20 2019-02-01 广州市恒德环保材料有限公司 A kind of PVC complex material
CN108635241A (en) * 2018-06-07 2018-10-12 上海蔻沣生物科技有限公司 One kind having thixotropic oiliness slurry and preparation method thereof
CN110451835A (en) * 2019-09-17 2019-11-15 安徽好思家涂料股份有限公司 A kind of artificial color sand of high abrasion low-temperature sintering and preparation method thereof
CN110451835B (en) * 2019-09-17 2022-03-01 安徽好思家涂料股份有限公司 High-wear-resistance low-temperature sintered artificial colored sand and preparation method thereof
CN113881227A (en) * 2021-11-20 2022-01-04 彩虹高新材料（莱阳）有限公司 Ultraviolet-resistant polyether sulfone resin and preparation method thereof
CN113881227B (en) * 2021-11-20 2023-11-07 彩虹高新材料（莱阳）有限公司 Ultraviolet-resistant polyether sulfone resin and preparation method thereof
CN114507080A (en) * 2022-02-17 2022-05-17 广东欧文莱陶瓷有限公司 High-toughness ceramic sheet and preparation method thereof
CN114507080B (en) * 2022-02-17 2022-11-25 广东欧文莱陶瓷有限公司 High-toughness ceramic sheet and preparation method thereof
CN115851000A (en) * 2022-12-06 2023-03-28 龙佰禄丰钛业有限公司 Method and device for drying titanium dioxide filter cake by contact change promotion

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