KR20030026266A - A process for preparing an ultrafine particle of brookite-type titanium oxide, using titanium tetrachloride and aqueous hydrochloric acid - Google Patents

A process for preparing an ultrafine particle of brookite-type titanium oxide, using titanium tetrachloride and aqueous hydrochloric acid Download PDF

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KR20030026266A
KR20030026266A KR1020030009408A KR20030009408A KR20030026266A KR 20030026266 A KR20030026266 A KR 20030026266A KR 1020030009408 A KR1020030009408 A KR 1020030009408A KR 20030009408 A KR20030009408 A KR 20030009408A KR 20030026266 A KR20030026266 A KR 20030026266A
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양영석
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(주)아해
양영석
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    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00Compounds of titanium
    • C01G23/04Oxides; Hydroxides
    • C01G23/047Titanium dioxide
    • C01G23/053Producing by wet processes, e.g. hydrolysing titanium salts
    • C01G23/0536Producing by wet processes, e.g. hydrolysing titanium salts by hydrolysing chloride-containing salts
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/51Particles with a specific particle size distribution
    • C01P2004/52Particles with a specific particle size distribution highly monodisperse size distribution
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/60Particles characterised by their size
    • C01P2004/64Nanometer sized, i.e. from 1-100 nanometer

Abstract

PURPOSE: Provided is a simple preparation method of brookite TiO2 nanoparticles by regulating the concentration of HCl in a titanium solution and forming precipitates at low temperature. CONSTITUTION: The preparation method of brookite nanoparticle TiO2(50-100nm) comprises the steps of: preparing a titanium solution containing 1.0-8.0M of HCl by dropping 0.001-12.0M of HCl to TiCl4 to get a titanium stock solution, and adding aqueous HCl and distilled water; standing the solution at 30-80deg.C, preferably 50-70deg.C, to form precipitates; collecting precipitates and adjusting the pH of the solution between 2-8 with an alkali solution, non metal hydroxide solution such as NaOH, KOH or NH4OH; collecting precipitates from the solution; washing formed precipitates with water to remove remained bases; drying formed precipitates at room temperature or 40deg.C for 48hrs.

Description

사염화티타늄 및 염산수용액을 사용한 브루카이트상 이산화티타늄의 초미세 입자의 제조방법{A process for preparing an ultrafine particle of brookite-type titanium oxide, using titanium tetrachloride and aqueous hydrochloric acid}A process for preparing an ultrafine particle of brookite-type titanium oxide, using titanium tetrachloride and aqueous hydrochloric acid}

본 발명은 사염화티타늄과 염산수용액을 사용한 브루카이트상을 가지는 이산화티타늄(TiO2)의 초미세 입자의 제조방법에 관한 것이다.The present invention relates to a method for producing ultrafine particles of titanium dioxide (TiO 2 ) having a brookite phase using titanium tetrachloride and an aqueous hydrochloric acid solution.

TiO2는 결정구조에 따라 루틸(Rutile)상, 아나타제(Anatase)상 및 브루카이트(Brookite)상 등으로 구분되며, 이 가운데 아나타제상 및 브루카이트상은 고온에서 비가역 과정을 통하여 루틸상으로 전환되는 것으로 알려져 있다. 현재까지 알려진 이산화티타늄 제조방법은 황산법, 염소법, 수열법, 졸-겔법 및 침전법 등이 있다. 그러나, 브루카이트상 이산화티타늄 제조에 대한 연구는 현재까지 활발하게 진행되지 않는 상태이며, 아나타제상이나 루틸상이 혼재되어 있지 않은 순수한 브루카이트상의 제조는 매우 어려운 것으로 알려져 있다. 따라서, 이와 같은 제조상의 어려움이 광촉매와 촉매지지체로서 브루카이트상의 응용이 제한되는 원인중의 하나가 되고 있다.TiO 2 is divided into rutile phase, anatase phase and brookite phase according to crystal structure, among which anatase phase and brookite phase are converted to rutile phase at high temperature through irreversible process. Known. Titanium dioxide production methods known to date include sulfuric acid method, chlorine method, hydrothermal method, sol-gel method and precipitation method. However, research on the production of brookite phase titanium dioxide has not been actively carried out to date, and it is known that the production of pure brookite phase without anatase phase or rutile phase mixture is very difficult. Therefore, such a manufacturing difficulty is one of the reasons that the application of the brookite phase as a photocatalyst and catalyst support is limited.

브루카이트상 이산화티타늄을 제조하는 종래의 제조방법으로서, 미국특허 제6,340,711호에서는 출발물질로 사염화티타늄(TiCl4)을 사용하여 루틸상이 혼합된브루카이트상 이산화티타늄을 제조하였다. 이 방법은 사염화티타늄(TiCl4)에 증류수를 첨가한 후 50℃이상에서 가수분해 반응을 진행시켜 브루카이트상이 포함된 이산화티타늄을 제조하는 것으로, 브루카이트상의 함유율이 70%이상 포함된 입자제조를 위해서는 75℃∼100℃로 가열한 증류수를 첨가하여 75℃부터 티타늄수용액의 비점에 해당하는 온도범위에서 반응을 진행시킨다. 그러나, 이 방법으로 얻은 입자는 비 표면적이 약 20㎡/g이며, 평균입자크기가 약 500nm로서 초미세 입자(즉, 나노크기의 입자)라 할 수 없으며, 브루카이트상의 함유율을 증가시키기 위해 고온의 증류수를 사용하기 때문에, 사염화티타늄의 가수분해과정에서 발생하는 반응초기의 반응열을 효과적으로 제거하기 어려운 단점이 있다.As a conventional manufacturing method for producing brookite-type titanium dioxide, US Patent No. 6,340,711, using a titanium tetrachloride (TiCl 4 ) as a starting material to prepare a brookite-type titanium dioxide mixed with rutile phase. This method adds distilled water to titanium tetrachloride (TiCl 4 ) and then proceeds a hydrolysis reaction at 50 ° C. or higher to produce titanium dioxide containing a brookite phase. Particles containing 70% or more of brookite phase are prepared. In order to add distilled water heated to 75 ~ 100 ℃ to advance the reaction in the temperature range corresponding to the boiling point of the titanium aqueous solution from 75 ℃. However, the particles obtained by this method have a specific surface area of about 20 m 2 / g, and have an average particle size of about 500 nm, which cannot be called ultrafine particles (i.e. nano-sized particles), and have a high temperature to increase the content of brookite phase. Since distilled water is used, it is difficult to effectively remove the initial reaction heat generated during the hydrolysis of titanium tetrachloride.

또한, Pottier 등의 연구(J. of Materials Chemistry, 11, 1116-1121(2001))에 의하면 별도의 냉각장치 없이, 염산수용액과 과염소산(HClO4)에 TiCl4을 첨가하여 Ti+4농도가 0.15M이 되도록 희석한 후, 100℃에서 48시간 동안 열분해반응으로 브루카이트상의 부피분율이 50%이상을 차지하는 이산화티타늄 입자를 제조하였다. 이 방법에서 브루카이트상을 제조하기 위한 적정한 조건은 용액내 Cl-1 total: Ti+4의 몰비율이 17∼35의 범위가 유리하며, 용액의 Ti+4농도가 증가함에 따라 브루카이트상의 생성을 위한 반응조건인 Cl-1 total: Ti+4의 비율이 감소된다고 하였다. 또한, Ti+4농도가 증가함에 따라 브루카이트상 부피분율이 50%이상인 입자를 얻을 수 없으며, 반응온도가 높고 장시간의 반응시간이 요구될 뿐 아니라 순수한 브루카이트상의 제조가 불가능한 제조법이다.In addition, according to Pottier et al. (J. of Materials Chemistry, 11, 1116-1121 (2001)), Ti + 4 concentration is 0.15 by adding TiCl 4 to aqueous hydrochloric acid solution and perchloric acid (HClO 4 ) without a separate cooling device. After dilution to M, titanium dioxide particles having a volume fraction of brookite phase of 50% or more were prepared by pyrolysis at 100 ° C. for 48 hours. The suitable conditions for preparing the brookite phase in this method are advantageously in the range of 17-35 molar ratio of Cl -1 total : Ti +4 in the solution, and the formation of brookite phase as the Ti +4 concentration of the solution increases. The ratio of Cl -1 total : Ti +4 , which is a reaction condition for, was reduced. In addition, as the Ti + 4 concentration is increased, particles having a brookite phase volume fraction of 50% or more cannot be obtained, and a high reaction temperature and a long reaction time are required, and a pure brookite phase is impossible to prepare.

Ye 등의 연구결과(Nanostructure Materials, 8(7) 919-927(1997))에 의하면 2-에틸헥사놀(탄화수소) 및 소비탄 모노-올리에이트(계면활성제)를 첨가한 암모니아 수용액과 TiCl4를 사용하여 Ti(OH)4침전물을 제조하여 세척 및 건조한 후 열처리 과정을 거쳐 브루카이트상 40.8%, 아나타제상 32.7%, 루틸상 26.5%가 동시에 존재하는 혼합상을 제조하였다. 이 방법에 의하면 물성이 양호한 이산화티타늄이 생성되지만 가격이 비싼 유기용매와 계면활성제 같은 제3의 첨가물을 사용해야 하고, 침전물 제조 후 유기물 제거와 결정성 입자를 얻기 위하여 열처리 공정이 필요한 단점이 있다.According to the results of Ye et al. (Nanostructure Materials, 8 (7) 919-927 (1997)), TiCl 4 and ammonia aqueous solution containing 2-ethylhexanol (hydrocarbon) and sorbitan mono-oleate (surfactant) were added. Ti (OH) 4 precipitate was prepared, washed, dried, and heat-treated to prepare a mixed phase in which 40.8% of brookite, 32.7% of anatase, and 26.5% of rutile were simultaneously present. According to this method, titanium dioxide having good physical properties is produced, but an expensive organic solvent and a third additive such as a surfactant must be used, and a heat treatment process is required to remove organic matter and obtain crystalline particles after preparation of the precipitate.

Zheng 등의 연구(J. of American Ceramic Society, 83(10) 2634-2636 (2000), J. of Materials Science Letters, 19, 1445-1448(2000))에서는 TiCl4수용액에 NaOH 수용액을 첨가하여 제조한 무정형의 침전물을 증류수로 희석하고 245℃에서 12시간 반응시켜 순수한 브루카이트상을 제조하였다. 또한, Ti(SO4)2에 NaOH 수용액을 첨가하여 제조한 무정형의 침전물을 증류수로 희석하고 300℃에서 12시간 반응시켜 순수한 브루카이트상을 제조하였다. 그러나, 이 방법은 고온고압의 반응조건이 요구될 뿐 아니라 입자크기가 균일하지 못한 입자가 제조되는 단점이 있다.Zheng et al. (J. of American Ceramic Society, 83 (10) 2634-2636 (2000), J. of Materials Science Letters, 19, 1445-1448 (2000)) prepared by adding NaOH aqueous solution to aqueous TiCl 4 solution. One amorphous precipitate was diluted with distilled water and reacted at 245 ° C. for 12 hours to produce a pure brookite phase. In addition, an amorphous precipitate prepared by adding an aqueous NaOH solution to Ti (SO 4 ) 2 was diluted with distilled water and reacted at 300 ° C. for 12 hours to prepare a pure brookite phase. However, this method not only requires high temperature and high pressure reaction conditions, but also has disadvantages in that particles having a uniform particle size are produced.

Kominami 등의 연구(J. of Materials Chemistry, 10, 1151-1156(2000))에 의하면 옥소비스(2,4-펜탄디오나토-O,O)티타늄 [TiO(acac)2]소듐 라우레이트(sodium laurate)에 에틸렌글리콜을 첨가하고 300℃에서 2시간 반응시켜 순수한 브루카이트상 이산화티타늄을 제조한다. 이 방법은 제조공정이 비교적 단순한 반면 격렬한 가수분해반응의 제어가 어려울 뿐 아니라 첨가된 유기물 제거를 위한 고온고압의 반응기가 요구되는 단점이 있다.According to Kominami et al. (J. of Materials Chemistry, 10, 1151-1156 (2000)), oxobis (2,4-pentanedioato-O, O) titanium [TiO (acac) 2 ] and sodium laurate ( Ethylene glycol was added to sodium laurate) and reacted at 300 ° C. for 2 hours to prepare pure brookite titanium dioxide. This method has a disadvantage in that while the manufacturing process is relatively simple, it is difficult to control the violent hydrolysis reaction and a high temperature and high pressure reactor for removing the added organic matter is required.

이 밖에 다른 연구보고에 의하면 브루카이트상은 산성 반응매개체가 존재하는 상태에서 저온으로 침전반응을 진행할 때 가끔씩 부산물로서 관찰된다고 하였다.Other research reports show that the brookite phase is sometimes observed as a by-product when precipitation occurs at low temperatures in the presence of an acidic reaction medium.

이상에서 검토된 바와 같이 현재까지 알려진 브루카이트상 이산화티타늄의 제조방법은 고온의 반응온도와 장시간의 반응시간이 요구될 뿐 아니라 고온고압 반응기의 사용이 필요하기 때문에 효율적인 제조방법의 개발이 요구된다.As discussed above, the production of brookite-type titanium dioxide known to date requires not only a high temperature reaction temperature and a long reaction time but also the use of a high temperature and high pressure reactor.

한편, 본 발명자는 이산화티타늄의 초미세 입자, 특히 루틸상 이산화티타늄의 초미세 입자의 제조방법을 개발하여 특허출원을 완료한 바 있다(대한민국 공개특허 제2002-0078637호). 즉, 사염화티타늄에 염산 등의 무기산 용액을 첨가하여 Ti+4의 농도가 0.1∼1.4M이 되도록 조절한 티타늄 수용액을 15~200℃에서 방치함으로써 침전물을 형성시켜 루틸상 이산화티타늄의 초미세 입자를 제조하는 방법을 개발한 바 있다.On the other hand, the present inventors have completed the patent application by developing a method for producing ultrafine particles of titanium dioxide, in particular, ultrafine particles of rutile titanium dioxide (Korean Patent No. 2002-0078637). That is, by adding an inorganic acid solution such as hydrochloric acid to titanium tetrachloride, the aqueous titanium solution adjusted to a concentration of Ti +4 of 0.1 to 1.4 M was left at 15 to 200 ° C to form a precipitate to form ultrafine particles of rutile titanium dioxide. We have developed a method of manufacturing.

본 발명자는 브루카이트상 이산화티타늄 초미세 입자의 제조방법을 개발하고자 연구를 거듭한 결과, 놀랍게도 티타늄 수용액중의 염산농도를 소정의 범위로 조정하고, 상대적으로 저온에서 침전물을 형성시킬 경우, 순수한 브루카이트상 이산화티타늄의 초미세 입자를 제조할 수 있는 것을 발견하게 되었다.The present inventors have conducted research to develop a method for preparing ultrafine titanium dioxide fine particles, and surprisingly, when adjusting the concentration of hydrochloric acid in an aqueous titanium solution to a predetermined range and forming a precipitate at a relatively low temperature, pure brew It has been found that ultrafine particles of kite titanium dioxide can be produced.

따라서, 본 발명은 상기 발견을 기초로 완성된 것으로, 본 발명은 단순한 제조공정으로 브루카이트상 이산화티타늄의 초미세 입자를 제조하는 방법을 제공하는 것을 목적으로 한다.Accordingly, the present invention has been completed based on the above findings, and an object of the present invention is to provide a method for producing ultrafine particles of brookite titanium dioxide by a simple manufacturing process.

도 1은 실시예1에서 제조한 브루카이트상 TiO2입자의 X-선 회절분석 결과를 나타낸 것이고,Figure 1 shows the results of X-ray diffraction analysis of the brookite TiO 2 particles prepared in Example 1,

도 2은 실시예2에서 제조한 브루카이트상 TiO2입자의 X-선 회절분석 결과를 나타낸 것이고,Figure 2 shows the results of X-ray diffraction analysis of the brookite TiO 2 particles prepared in Example 2,

도 3는 실시예2에서 제조한 브루카이트상 TiO2입자의 라만 스펙트럼 분석결과를 나타낸 것이고,Figure 3 shows the Raman spectrum analysis of the brookite TiO 2 particles prepared in Example 2,

도 4은 실시예3에서 제조한 브루카이트상 TiO2입자의 X-선 회절분석 결과를 나타낸 것이고,4 shows the results of X-ray diffraction analysis of the brookite TiO 2 particles prepared in Example 3,

도 5는 실시예4에서 제조한 브루카이트상 TiO2입자의 X-선 회절분석 결과를나타낸 것이고,5 shows the results of X-ray diffraction analysis of the brookite TiO 2 particles prepared in Example 4,

도 6는 실시예4에서 제조한 브루카이트상 TiO2입자의 투과전자현미경(TEM)사진을 나타낸 것이고,6 shows a transmission electron microscope (TEM) photograph of the brookite TiO 2 particles prepared in Example 4,

도 7은 실시예5에서 제조한 브루카이트상 TiO2입자의 X-선 회절분석 결과를 나타낸 것이이다.FIG. 7 shows the results of X-ray diffraction analysis of the brookite TiO 2 particles prepared in Example 5. FIG.

상기 본 발명의 목적을 달성하기 위하여, 본 발명은 a) 사염화티타늄(TiCl4)에 염산 수용액을 가하여 용액중의 염산농도가 1.0 ∼8.0 M인 티타늄 수용액을 제조하는 단계; b) 상기 a) 단계에서 얻어진 용액을 30∼80에서 방치하여 침전물을 형성시키는 단계; c) 상기 b) 단계에서 얻어진 침전물을 회수한 후, 알칼리 수용액으로 용액의 pH를 2∼8로 조절하는 단계; d) 상기 c) 단계에서 얻어진 용액 중의 침전물을 회수한 다음, 건조시키는 단계를 포함하는 브루카이트상 이산화티타늄의 초미세 입자의 제조방법을 제공한다.In order to achieve the object of the present invention, the present invention comprises the steps of: a) adding an aqueous hydrochloric acid solution to titanium tetrachloride (TiCl 4 ) to prepare a titanium aqueous solution having a hydrochloric acid concentration in the solution of 1.0 ~ 8.0 M; b) leaving the solution obtained in step a) at 30 to 80 to form a precipitate; c) recovering the precipitate obtained in the step b), and adjusting the pH of the solution to 2 to 8 with an aqueous alkali solution; d) recovering the precipitate in the solution obtained in step c), and then providing a method for producing ultrafine particles of brookite titanium dioxide comprising the step of drying.

본 발명의 제조방법은 상기 제 a) 단계에서 얻어진 용액에 초미세 사염화티탄 수용액 또는 이산화티타늄을 가하는 단계를 더 포함할 수 있으며, 또한 상기 a)단계는 사염화티타늄에 0.001~12.0M의 염산 수용액을 적가하여 티타늄 모액(stock solution)을 제조한 후, 염산수용액 또는 증류수를 가하여 용액중의 염산농도가 1.0∼8.0 M인 티타늄 수용액을 제조함으로써 수행할 수 있다.The preparation method of the present invention may further include the step of adding an ultra-fine titanium tetrachloride solution or titanium dioxide to the solution obtained in step a), and the step a) is a hydrochloric acid solution of 0.001 ~ 12.0M in titanium tetrachloride After dropwise addition to prepare a titanium stock solution, it can be carried out by adding aqueous hydrochloric acid solution or distilled water to prepare a titanium aqueous solution having a hydrochloric acid concentration of 1.0 ~ 8.0 M in the solution.

또한, 본 발명의 제조방법에 있어서, 상기 b) 단계는 50~70℃의 범위에서 바람직하게 수행할 수 있으며, 상기 c) 단계의 알칼리 수용액은 비금속 수산화물의 수용액을 사용할 수 있다.In addition, in the production method of the present invention, the step b) may be preferably performed in the range of 50 ~ 70 ℃, the aqueous alkali solution of step c) may be used an aqueous solution of a non-metal hydroxide.

이하, 본 발명을 더욱 상세하게 설명한다.Hereinafter, the present invention will be described in more detail.

본 명세서에서 사용하는 "브루카이트상 이산화티타늄"이라는 용어는 실질적으로 루틸상 및 아나타제상이 함유되어 있지 않는 순수한 브루카이트상의 이산화티타늄을 말하며, 통상 95%이상, 바람직하게는 98%이상, 더욱 바람직하게는 99%이상이 브루카이트상인 이산화티타늄을 의미한다.As used herein, the term " brookite titanium dioxide " refers to pure brookite titanium dioxide that is substantially free of rutile and anatase phases, usually at least 95%, preferably at least 98%, more preferably Means more than 99% of titanium dioxide in the brookite phase.

또한, 본 명세서에서 사용하는 "초미세 입자"라는 용어는 "나노크기(nano-size)의 입자"를 말하며, 통상 평균입자 크기가 50~100nm, 바람직하게는 30∼50nm, 더욱 바람직하게는 10∼20nm인 입자를 의미한다.In addition, the term "ultrafine particles" as used herein refers to "nano-size particles", and the average particle size is usually 50-100 nm, preferably 30-50 nm, more preferably 10 It means the particle which is -20nm.

본 발명의 제조방법 중, a)단계는 염산농도가 1.0∼8.0M인 티타늄 수용액을 제조하는 단계로 이루어진다. 상기 티타늄 수용액을 제조함에 있어서는 사염화티타늄에 0.001~12.0M의 염산 수용액을 적가하여 티타늄 모액(stock solution)을 제조한 후, 염산수용액 또는 증류수를 가하여 용액중의 염산농도가 1.0∼8.0M인 티타늄 수용액을 제조하는 것이 바람직하다. 또한 상기 단계는 상온에서 수행할 수 있다.In the production method of the present invention, step a) consists of preparing a titanium aqueous solution having a hydrochloric acid concentration of 1.0 to 8.0M. In preparing the aqueous titanium solution, 0.001 to 12.0 M hydrochloric acid solution is added dropwise to titanium tetrachloride to prepare a titanium stock solution, and then, an aqueous hydrochloric acid solution or distilled water is added to the aqueous titanium solution having a concentration of 1.0 to 8.0 M. It is preferable to prepare. In addition, the step may be performed at room temperature.

상기와 같이 제조한 티타늄 수용액은 TiOCl2및 HCl이 함유된 수용액이 얻어지게 되며, Ti+4의 농도는 0.001∼1.8M, 더욱 바람직하게는 0.05∼1.6M 범위의 농도를 가지는 것이 바람직하다. 상기 a)단계에서 2차로 가하는 염산수용액 또는 증류수에 있어서, 염산수용액의 농도는 최종 염산농도를 고려하여 조절할 수 있으나,통상 0.001∼8.0M이 바람직하며, 1차로 가해지는 염산수용액의 농도가 높은 농도일 경우(예를 들어, 약 12M)에는 증류수를 가함으로써 전체 염산농도를 조절할 수 있다.Titanium aqueous solution prepared as described above is obtained an aqueous solution containing TiOCl 2 and HCl, the concentration of Ti + 4 is preferably in the range of 0.001 ~ 1.8M, more preferably 0.05 ~ 1.6M. In the aqueous hydrochloric acid solution or distilled water added in the second step a), the concentration of the hydrochloric acid solution may be adjusted in consideration of the final hydrochloric acid concentration, but usually 0.001 to 8.0M is preferred, and the concentration of the aqueous hydrochloric acid solution to be applied first is high. In one case (eg, about 12M), the total hydrochloric acid concentration can be adjusted by adding distilled water.

본 발명의 제조방법은 침전물 형성을 촉진하기 위한 단계로서, 상기와 같이 제조한 티타늄 수용액에 핵(seed) 물질로서 초미세 사염화티탄 수용액 또는 이산화티타늄을 핵물질로서 작용할 수 있는 통상적인 양으로 가할 수 있으나, 바람직하게는 1~50ml로, 더욱 바람직하게는 5~30ml로 가하는 단계를 더 포함할 수 있다.The manufacturing method of the present invention is a step for promoting the formation of precipitates, it can be added to the titanium aqueous solution prepared as described above in a conventional amount capable of acting as a nuclear material ultrafine titanium tetrachloride solution or titanium dioxide as a nuclear material. However, preferably 1 to 50ml, more preferably 5 to 30ml may be further included.

본 발명의 제조방법에 있어서, 침전물을 생성시키는 단계 즉 b)단계는 상기와 같은 방법으로 제조한 티타늄 수용액을 30~80℃, 더욱 바람직하게는 50~70℃에서 방치함으로써 수행할 수 있으며, 이때 얻어지는 침전물은 슬러리 형태를 가지게 된다.In the production method of the present invention, the step of generating a precipitate, that is, step b) may be performed by leaving the titanium aqueous solution prepared by the above method at 30 ~ 80 ℃, more preferably 50 ~ 70 ℃, this time, The precipitate obtained is in the form of a slurry.

본 발명의 제조방법은 상기에서 얻어진 슬러리 형태의 침전물을 회수한 후, 알칼리 수용액으로 용액의 pH를 2∼8로 조절하는 단계를 포함한다. 여기에서, 침전물의 회수는 통상의 방법, 예를 들어 여과 등의 방법을 통하여 회수할 수 있으며, 회수된 침전물은 정제수, 증류수, 등의 물로 약 3회 정도 세정하여 잔류할 수 있는 염기를 제거하는 것이 바람직하다. 또한, pH 조절을 위해서 가하는 알칼리 수용액으로는 비금속 수산화물의 수용액을 사용할 수 있으며, 예를 들면 NaOH, KOH, 또는 NH4OH 등의 수용액을 바람직하게 사용할 수 있다.The method of the present invention includes recovering the precipitate in the form of slurry obtained above, and adjusting the pH of the solution to 2 to 8 with an aqueous alkali solution. Here, the recovery of the precipitate can be recovered through a conventional method, for example, by filtration, etc., and the recovered precipitate is washed three times with purified water, distilled water, or the like to remove remaining base. It is preferable. Also, with an aqueous alkali solution applied to the pH adjustment may be used an aqueous solution of a base metal hydroxide, for example, it can be preferably used an aqueous solution, such as NaOH, KOH, or NH 4 OH.

본 발명의 제조방법은 상기에서 얻어진 용액중의 침전물을 회수한 다음, 건조시키는 단계를 포함한다. 침전물의 회수는 통상의 방법 즉 여과 등의 방법으로 회수할 수 있으며, 회수한 침전물은 정제수, 증류수 등의 물로 약 3회 정도 세정하는 것이 바람직하고, 통상의 건조방법 예를 들어 상온 또는 약 40℃에서 약 48시간동안 건조시킬 수 있다.The production method of the present invention includes the step of recovering the precipitate in the solution obtained above, followed by drying. The precipitate can be recovered by a conventional method, that is, by filtration or the like, and the recovered precipitate is preferably washed about three times with water such as purified water and distilled water, and is usually dried at room temperature or about 40 ° C. Can be dried for about 48 hours.

이하, 실시예를 통하여 본 발명을 더욱 상세히 설명한다. 그러나 이들 실시예는 단지 본 발명을 예시하기 위한 것이므로, 본 발명의 범위가 이들 실시예에 의해 제한되는 것으로 해석되지는 않는다.Hereinafter, the present invention will be described in more detail with reference to Examples. However, these examples are only for illustrating the present invention, and the scope of the present invention is not to be construed as being limited by these examples.

실시예 1Example 1

반응기에 사염화티타늄 20ml 를 넣은 후, 12.0M 염산수용액 20ml를 적가하여 Ti+4의 농도가 4.55M인 모액(stock solution)을 제조하였다. 이렇게 제조한 모액 2.2ml 와 3.0M 염산수용액 197.8㎖를 혼합하였다. 이때 용액 중 Ti+4의 농도는 약 0.05M이었으며, HCl의 농도는 3.05M이었다.After adding 20 ml of titanium tetrachloride to the reactor, 20 ml of 12.0 M aqueous hydrochloric acid solution was added dropwise to prepare a stock solution having a concentration of 4.55 M of Ti +4 . 2.2 ml of the mother liquor thus prepared and 197.8 ml of 3.0M aqueous hydrochloric acid solution were mixed. At this time, the concentration of Ti +4 in the solution was about 0.05M, HCl concentration was 3.05M.

상기 용액을 50℃에서 90시간 동안 방치하여 침전물을 형성시키고, 여과하여 얻은 슬러리 형태의 침전물을 증류수로 3회 세정한 다음, 3.0M의 NaOH 수용액을 첨가하여 용액의 pH를 pH 2 로 조절하였다. 얻어진 용액을 여과하여 침전물을 얻은 다음, 증류수로 3회 세정한 후 40℃에서 48시간 동안 건조하여 브루카이트상 이산화티타늄의 초미세 입자를 얻었다.The solution was left at 50 ° C. for 90 hours to form a precipitate, and the precipitate in the form of a slurry obtained by filtration was washed three times with distilled water, and then the pH of the solution was adjusted to pH 2 by adding 3.0 M aqueous NaOH solution. The resulting solution was filtrated to obtain a precipitate, which was then washed three times with distilled water and dried at 40 ° C. for 48 hours to obtain ultrafine particles of brookite titanium dioxide.

도 1은 상기와 같이 제조한 입자의 X-선 회절분석한 결과를 나타낸 것으로, 순수한 브루카이트상 이산화티타늄 초미세 입자가 얻어진 것을 확인할 수 있다. 또한, X-선 회절분석로부터 쉐러식(Scherrer equation)을 이용하여 계산한 평균입자크기는 약 12nm 였다.Figure 1 shows the results of the X-ray diffraction analysis of the particles prepared as described above, it can be confirmed that the pure brookite phase titanium dioxide ultrafine particles were obtained. In addition, the average particle size calculated using the Scherrer equation from the X-ray diffraction analysis was about 12 nm.

실시예 2.Example 2.

반응기에 사염화티타늄 100㎖ 를 넣은 후, 1.0M 염산수용액 73 ml를 적가하여 Ti+4의 농도가 5.27M인 모액(stock solution)을 제조하였다. 이렇게 제조한 모액 15㎖와 4.0M 염산수용액 185㎖를 혼합하였다. 이때 용액 중 Ti+4의 농도는 약 0.4M이었으며, HCl의 농도는 4.5M이었다.100 ml of titanium tetrachloride was added to the reactor, and 73 ml of 1.0M aqueous hydrochloric acid solution was added dropwise to prepare a stock solution having a concentration of Ti +4 of 5.27M. 15 ml of the mother liquor thus prepared and 185 ml of 4.0M aqueous hydrochloric acid solution were mixed. At this time, the concentration of Ti +4 in the solution was about 0.4M, the concentration of HCl was 4.5M.

상기 용액을 70℃에서 24시간 동안 방치하여 침전물을 형성시키고, 여과하여 얻은 슬러리 형태의 침전물을 증류수로 3회 세정한 다음, 1.0M의 NaOH 수용액을 첨가하여 용액의 pH를 pH5로 조절하였다. 얻어진 용액을 여과하여 침전물을 얻은 다음, 증류수로 3회 세정한 후 40℃에서 48시간 동안 건조하여 브루카이트상 이산화티타늄의 초미세 입자를 얻었다.The solution was left at 70 ° C. for 24 hours to form a precipitate, and the precipitate in the form of a slurry obtained by filtration was washed three times with distilled water, and then the pH of the solution was adjusted to pH 5 by adding 1.0 M aqueous NaOH solution. The resulting solution was filtrated to obtain a precipitate, which was then washed three times with distilled water and dried at 40 ° C. for 48 hours to obtain ultrafine particles of brookite titanium dioxide.

도 2는 상기와 같이 제조한 입자의 X-선 회절분석한 결과를 나타낸 것으로, 순수한 브루카이트상 이산화티타늄 초미세 입자가 얻어진 것을 확인할 수 있다. 또한, 도 3은 이렇게 얻은 초미세 입자의 라만 스텍트럼(Raman spectra) 분석결과를 나타낸 것으로, 322, 366, 412, 454, 502, 545, 585, 636㎝-1에서 피크가 나타나 순수한 브루카이트상임을 확인할 수 있다. 또한, X-선 회절분석으로부터 쉐러식(Scherrer equation)을 이용하여 계산한 평균입자크기는 약 10.5nm 였다.Figure 2 shows the results of the X-ray diffraction analysis of the particles prepared as described above, it can be seen that the pure brookite phase titanium dioxide ultrafine particles were obtained. In addition, Figure 3 shows the Raman spectra (Raman spectra) analysis results of the ultra-fine particles thus obtained, the peak appears at 322, 366, 412, 454, 502, 545, 585, 636 cm -1 to be pure brookite phase You can check it. In addition, the average particle size calculated using the Scherrer equation from the X-ray diffraction analysis was about 10.5 nm.

실시예 3.Example 3.

반응기에 사염화티타늄 20ml 을 넣은 후, 2.0M 염산수용액 20ml를 적가하여 Ti+4의 농도가 5.0M인 모액(stock solution)을 제조하였다. 이렇게 제조한 모액 24㎖와 3.5M 염산수용액 176㎖를 혼합하였다. 이때 용액 중 Ti+4의 농도는 0.6M이었으며, HCl의 농도는 4.6M이었다.After adding 20 ml of titanium tetrachloride to the reactor, 20 ml of 2.0M aqueous hydrochloric acid solution was added dropwise to prepare a stock solution having a concentration of 5.0M of Ti +4 . Thus prepared mother solution 24ml and 3.5M aqueous hydrochloric acid solution 176ml was mixed. At this time, the concentration of Ti +4 in the solution was 0.6M, the concentration of HCl was 4.6M.

상기 용액을 60℃에서 36시간 동안 방치하여 침전물을 형성시키고, 여과하여 얻은 슬러리 형태의 침전물을 증류수로 3회 세정한 다음, 1.0M의 KOH 수용액을 첨가하여 용액의 pH를 pH 4.5로 조절하였다. 얻어진 용액을 여과하여 침전물을 얻은 다음, 증류수로 3회 세정한 후 40℃에서 48시간 동안 건조하여 브루카이트상 이산화티타늄의 초미세 입자를 얻었다.The solution was left at 60 ° C. for 36 hours to form a precipitate, and the precipitate in the form of a slurry obtained by filtration was washed three times with distilled water, and then the pH of the solution was adjusted to pH 4.5 by adding 1.0 M aqueous KOH solution. The resulting solution was filtrated to obtain a precipitate, which was then washed three times with distilled water and dried at 40 ° C. for 48 hours to obtain ultrafine particles of brookite titanium dioxide.

도 4는 상기와 같이 제조한 입자의 X-선 회절분석한 결과를 나타낸 것으로, 순수한 브루카이트상 이산화티타늄 초미세 입자가 얻어진 것을 확인할 수 있다. 또한, X-선 회절분석로부터 쉐러식(Scherrer equation)을 이용하여 계산한 평균입자크기는 약 11nm 였다.Figure 4 shows the results of the X-ray diffraction analysis of the particles prepared as described above, it can be confirmed that the pure brookite phase titanium dioxide ultrafine particles were obtained. In addition, the average particle size calculated using the Scherrer equation from the X-ray diffraction analysis was about 11 nm.

실시예 4.Example 4.

반응기에 사염화티타늄 200ml 를 넣은 후, 3.0M 염산수용액 185ml를 적가하여 Ti+4의 농도가 4.7M인 모액(stock solution)을 제조하였다. 이렇게 제조한 모액 34㎖와 3.0M 염산수용액 166㎖를 혼합하였다. 이때 용액 중 Ti+4의 농도는 0.8M이었으며, HCl의 농도는 4.7M이었다.After 200 ml of titanium tetrachloride was added to the reactor, 185 ml of 3.0M aqueous hydrochloric acid solution was added dropwise to prepare a stock solution having a concentration of 4.7M of Ti +4 . 34 ml of the mother liquor thus prepared and 166 ml of 3.0M aqueous hydrochloric acid solution were mixed. At this time, the concentration of Ti +4 in the solution was 0.8M, HCl was 4.7M.

상기 용액을 50℃에서 72시간 동안 방치하여 침전물을 형성시키고, 여과하여 얻은 슬러리 형태의 침전물을 증류수로 3회 세정한 다음, 2.0M의 NH4OH 수용액을 첨가하여 용액의 pH를 pH7로 조절하였다. 얻어진 용액을 여과하여 침전물을 얻은 다음, 증류수로 3회 세정한 후 상온에서 48시간 동안 건조하여 브루카이트상 이산화티타늄의 초미세 입자를 얻었다.The solution was left at 50 ° C. for 72 hours to form a precipitate, and the precipitate in the form of a slurry obtained by filtration was washed three times with distilled water, and then the pH of the solution was adjusted to pH 7 by adding 2.0 M aqueous NH 4 OH solution. . The resulting solution was filtered to obtain a precipitate, which was then washed three times with distilled water and dried at room temperature for 48 hours to obtain ultrafine particles of brookite titanium dioxide.

도 5는 상기와 같이 제조한 입자의 X-선 회절분석한 결과를 나타낸 것으로, 순수한 브루카이트상 이산화티타늄 초미세 입자가 얻어진 것을 확인할 수 있다. 또한, 도 6은 상기에서 제조한 입자의 TEM사진을 나타낸 것으로서, 입자크기가 5nm∼20nm인 구형의 형태를 나타내고 있으며, BET법으로 측정한 비표면적은 약 184.34㎡/g이었다.Figure 5 shows the results of the X-ray diffraction analysis of the particles prepared as described above, it can be seen that the pure brookite phase titanium dioxide ultrafine particles were obtained. 6 shows TEM photographs of the particles prepared above, and shows a spherical shape having a particle size of 5 nm to 20 nm, and the specific surface area measured by BET method was about 184.34 m 2 / g.

실시예 5Example 5

반응기에 사염화티타늄 250ml 를 넣은 후, 1.0M 염산수용액 190ml를 적가하여 Ti+4의 농도가 4.55M인 모액(stock solution)을 제조하였다. 이렇게 제조한 모액 61.6㎖와 1.0M 염산수용액 138.4㎖를 혼합하였다. 이때 용액 중 Ti+4의 농도는 약 1.6M이었으며, HCl의 농도는 4.0M이었다.After adding 250 ml of titanium tetrachloride to the reactor, 190 ml of 1.0M aqueous hydrochloric acid solution was added dropwise to prepare a stock solution having a concentration of 4.55M of Ti +4 . 61.6 ml of the mother liquor thus prepared and 138.4 ml of 1.0M aqueous hydrochloric acid solution were mixed. At this time, the concentration of Ti +4 in the solution was about 1.6M, the concentration of HCl was 4.0M.

상기 용액을 80℃에서 15시간 동안 방치하여 침전물을 형성시키고, 여과하여 얻은 슬러리 형태의 침전물을 증류수로 3회 세정한 다음, 1.0M의 NH4OH 수용액을 첨가하여 용액의 pH를 pH8로 조절하였다. 얻어진 용액을 여과하여 침전물을 얻은 다음, 증류수로 3회 세정한 후 60℃에서 48시간 동안 건조하여 브루카이트상 이산화티타늄의 초미세 입자를 얻었다.The solution was left at 80 ° C. for 15 hours to form a precipitate, and the precipitate in the form of a slurry obtained by filtration was washed three times with distilled water, and then the pH of the solution was adjusted to pH 8 by adding 1.0 M aqueous NH 4 OH solution. . The resulting solution was filtrated to obtain a precipitate, which was then washed three times with distilled water and dried at 60 ° C. for 48 hours to obtain ultrafine particles of brookite titanium dioxide.

도 7는 상기와 같이 제조한 입자의 X-선 회절분석한 결과를 나타낸 것으로, 순수한 브루카이트상 이산화티타늄 초미세 입자가 얻어진 것을 확인할 수 있다. 또한, X-선 회절분석로부터 쉐러식(Scherrer equation)을 이용하여 계산한 평균입자크기는 약 11.5nm 였다.Figure 7 shows the results of the X-ray diffraction analysis of the particles prepared as described above, it can be confirmed that the pure brookite phase titanium dioxide ultrafine particles were obtained. In addition, the average particle size calculated using the Scherrer equation from the X-ray diffraction analysis was about 11.5 nm.

이상 설명한 바와 같이, 본 발명에 따르면 나노크기를 갖고 입도분포가 균일한 순수한 브루카이트상 이산화티타늄 입자를 간단한 공정과 저렴한 비용으로 제조할 수 있다. 따라서, 제조상의 어려움으로 인하여 사용되지 않았던 브루카이트상 이산화티타늄 초미세 입자 적용분야의 다양화 및 시장성 확대를 이룰 수 있다.As described above, according to the present invention, pure brookite-type titanium dioxide particles having a nano size and a uniform particle size distribution can be manufactured in a simple process and at low cost. Therefore, it is possible to diversify and expand the marketability of the application of brookite-type titanium dioxide ultrafine particles which have not been used due to manufacturing difficulties.

Claims (5)

a) 사염화티타늄(TiCl4)에 염산 수용액을 가하여 용액중의 염산농도가 1.0 ∼ 8.0 M인 티타늄 수용액을 제조하는 단계;a) adding an aqueous hydrochloric acid solution to titanium tetrachloride (TiCl 4 ) to prepare an aqueous titanium solution having a hydrochloric acid concentration of 1.0 to 8.0 M in the solution; b) 상기 a) 단계에서 얻어진 용액을 30∼80℃에서 방치하여 침전물을 형성시키는 단계;b) leaving the solution obtained in step a) at 30-80 ° C. to form a precipitate; c) 상기 b) 단계에서 얻어진 침전물을 회수한 후, 알칼리 수용액으로 용액의 pH를 2∼8로 조절하는 단계;c) recovering the precipitate obtained in the step b), and adjusting the pH of the solution to 2 to 8 with an aqueous alkali solution; d) 상기 c) 단계에서 얻어진 용액 중의 침전물을 회수한 다음, 건조시키는 단계를 포함하는 브루카이트상 이산화티타늄의 초미세 입자의 제조방법.d) recovering the precipitate in the solution obtained in step c), and then drying the ultrafine particles of brookite titanium dioxide. 제1항에 있어서, 상기 a) 단계에서 얻어진 용액에 초미세 사염화티탄 수용액 또는 이산화티타늄을 가하는 단계를 더 포함하는 것을 특징으로 하는 제조방법.The method according to claim 1, further comprising adding an ultra-fine titanium tetrachloride solution or titanium dioxide to the solution obtained in step a). 제1항 또는 제2항에 있어서, 상기 a)단계가 사염화티타늄에 0.001~12.0M의 염산 수용액을 적가하여 티타늄 모액(stock solution)을 제조한 후, 염산수용액 또는 증류수를 가하여 용액중의 염산농도가 1.0∼8.0 M인 티타늄 수용액을 제조하는 것으로 이루어짐을 특징으로 하는 제조방법.The hydrochloric acid concentration in the solution according to claim 1 or 2, wherein step a) comprises adding a hydrochloric acid solution of 0.001 to 12.0 M dropwise to titanium tetrachloride to prepare a titanium stock solution, and then adding an aqueous hydrochloric acid solution or distilled water. Is 1.0-8.0 M of titanium solution. 제1항 또는 제2항에 있어서, 상기 b) 단계의 온도가 50∼70℃인 것을 특징으로 하는 제조방법.The method according to claim 1 or 2, wherein the temperature of step b) is from 50 to 70 ° C. 제1항 또는 제2항에 있어서, 상기 d) 단계의 알칼리 수용액이 비금속 수산화물의 수용액인 것을 특징으로 하는 제조방법.The method according to claim 1 or 2, wherein the aqueous alkali solution of step d) is an aqueous solution of a nonmetallic hydroxide.
KR10-2003-0009408A 2003-02-14 2003-02-14 A process for preparing an ultrafine particle of brookite-type titanium oxide, using titanium tetrachloride and aqueous hydrochloric acid KR100519039B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100579911C (en) * 2007-11-23 2010-01-13 中国科学院过程工程研究所 Method for low-temperature synthesis of titanium dioxide nano powder

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