201141609 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種具有作爲光觸媒、氧化觸媒有用的 結晶面（001)之金紅石型氧化鈦之製造方法。 【先前技術】 所謂光觸媒反應係一旦將紫外線照射於具有光觸媒性 能之固體化合物時，激發電子與電子離開後之洞（正電洞： hole )將生成，該激發電子係具有還原作用，該正電洞係 具有強的氧化作用，藉由此等作用而氧化或是還原反應物 之反應。習知具有代表性之光觸媒性能的固體化合物係氧 化鈦。氧化鈦係一旦吸收紫外線時，能夠發揮強的氧化作 用。例如，已被應用於空氣淨化、水質淨化、污染防止、 除臭、抗菌、醫院內感染防止、防霧等廣泛之用途。 氧化鈦之主要晶形習知爲金紅石型與銳鈦礦型。與非 晶性氧化鈦（非晶形）作一比較，此等之結晶性氧化鈦係 顯示高的化學安定性且大的折射率。而且，已知與結晶度 低的氧化鈦粉末作一比較，結晶度高的氧化鈦粒子能夠發 揮優異的光觸媒性能，結晶之尺寸越大，發揮越優異的光 觸媒性能。 於專利文獻1中，記載有對氧化鈦實施鹼性過氧化氫 水處理、硫酸處理、或氣氟酸處理而製作表現新穎結晶面 的氧化鈦結晶之方法，也記載所獲得之表現新穎結晶面的 氧化鈦而成的光觸媒係具有高的氧化觸媒性能。該表現新 201141609 穎結晶面的氧化鈦已被揭示：（1 )由金紅石型氧化鈦所獲 得之表現新穎（1 2 1 )面的氧化鈦結晶、（2 )由金紅石型 氧化鈦所獲得之表現新穎（〇〇1) (121) (〇21) (010) 面的氧化鈦結晶、（3 )由金紅石型氧化鈦所獲得之表現新 穎（02 1)面的氧化鈦結晶、（4 )由銳鈦礦型氧化鈦所獲 得之表現新穎（120)面的氧化鈦結晶、（5)由銳鈦礦型 氧化鈦所獲得之表現新穎（1 22 )面的氧化鈦結晶、（6 ) 由銳鈦礦型氧化鈦所獲得之表現新穎（1 1 2 )面的氧化鈦結 晶。 另外’於專利文獻2中，記載有藉由以1 5 0 °C以上之溫 度、在此溫度之飽和蒸氣壓以上之壓力下將鈦化合物水 解，而銳鈦礦型與金紅石型會混合存在的氧化鈦，能夠獲 得結晶度高、粒徑一致之微粒氧化鈦，進一步藉由調整鈦 化合物之濃度而能夠容易控制銳鈦礦型與金紅石型之組成 比率。 然而，基於光觸媒性能之觀點，利用上述之製造方法 所獲得之金紅石型氧化鈦並非能夠充分地滿足。亦即，現 狀尙未發現具有能夠充分地滿足之光觸媒活性的金紅石型 氧化鈦之製造方法。 〔先前技術文獻〕 〔專利文獻〕 專利文獻：日本特開2005 -29 8296號公報 專利文獻：日本特開2002- 1 54824號公報 201141609 【發明內容】 〔發明所欲解決之問題〕 因而’本發明之目的在於提供一種具有高的光觸媒活 性的金紅石型氧化鈦之製造方法。 〔用以解決問題之手段〕 本發明人等爲了解決上述問題而鑽硏探討之結果，發 現通常一旦在水性介質中進行三氯化鈦等之3價鈦化合物 的水熱處理時，雖然可以獲得具有結晶面（11 〇 ) (111) 之桿狀金紅石型氧化鈦，但若於特定之溫度、壓力下，對 4價鈦化合物實施特定時間之水熱處理時，能夠獲得具有 結晶面（00 1 )( 1 1 0 )( 1 1 1 )之桿狀金紅石型氧化鈦（參 閱第1圖）、及具有所獲得之結晶面（〇〇1) (110) (111) 之桿狀金紅石型氧化鈦，可發揮優異的光觸媒性能。本發 明係基於此等之見解所完成者。 亦即，本發明係提供一種金紅石型氧化鈦之製造方. 法，其特徵係藉由在反應溫度1 10°C至220°C、在此反應溫 度中之飽和蒸氣壓以上之壓力下，在水性介質中，對4價 鈦化合物實施2小時以上之水熱處理，而獲得具有結晶面 (001) (110) (111)之桿狀金紅石型氧化鈦。 4價鈦化合物較佳爲四氯化鈦。 另外，水性介質中之4價鈦化合物濃度較佳爲調整至 1.5至17.0重量％ (鈦換算）之範圍內》 還有，較佳爲交付藉由交叉流動方式而進行上述所獲 201141609 得之桿狀金紅石型氧化鈦的膜過濾之操作，尤其，藉由交 叉流動方式而進行桿狀金紅石型氧化鈦爲濃度爲〇.丨至40 重量％的桿狀金紅石型氧化鈦水分散液之膜過濾，獲得與 透過液一倂分離去除離子性不純物所濃縮的桿狀金紅石型 氧化鈦水分散液’將水加入該所濃縮的桿狀金紅石型氧化 鈦水分散液中’使桿狀金紅石型氧化鈦濃度稀釋成爲上述 範圍’藉由再度重複藉由交叉流動方式的膜過濾操作來精 製桿狀金紅石型氧化鈦的同時，也定期地逆洗淨濾膜爲較 佳。 〔發明之效果〕 若根據有關本發明之金紅石型氧化鈦之製造方法，藉 由於特定之條件下，在水性介質中實施4價鈦化合物之水 熱處理，能夠效率佳地合成具有結晶面（00 1 )之桿狀金紅 石型氧化鈦。若根據有關本發明之金紅石型氧化鈦之製造 方法，由於能夠使用四氯化鈦等之廉價原料，故能夠大幅 削減成本。另外，通常桿狀金紅石型係由結晶面（1 1 0 )與 (1 1 1 )所構成，結晶面（1 1 0 )係發揮還原部位、結晶面 (1 1 1 )係發揮氧化部位之作用，利用關於本發明之金紅石 型氧化鈦之製造方法所獲得之桿狀金紅石型氧化鈦係除了 結晶面（1 1 0 ) ( 1 1 1 )之外，也具有結晶面（0 0 1 )，由於 結晶面（1 1 0 )係發揮還原部位、結晶面（00 1 )與（1 1 1 ) 係發揮氧化部位之作用，具有更提高藉由照射紫外線所生 成的激發電子與所活化的正電洞之分離性的構造。因此， 201141609 能夠發揮強的氧化作用。若將利用關於本發明之金紅石型 氧化鈦之製造方法所獲得之桿狀金紅石型氧化鈦作爲光觸 媒使用時，由於能夠效率佳地氧化有機物質，有用於空氣 之淨化、除臭、淨水、抗菌、防污等之目的。 【實施方式】 〔用於實施發明之形態〕 有關本發明之金紅石型氧化鈦之製造方法，其特徵係 藉由在反應溫度1 10°c至220 °C、在此反應溫度中之飽和蒸 氣壓以上之壓力下，在水性介質中，對4價鈦化合物實施 2小時以上之水熱處理，而獲得具有結晶面（00丨）(11〇) (1 1 1 )之桿狀金紅石型氧化鈦。 (4價鈦化合物） 例如，本發明中之4價鈦化合物可舉例··下式（1 )所 代表之化合物等。[Technical Field] The present invention relates to a method for producing rutile-type titanium oxide having a crystal face (001) useful as a photocatalyst or an oxidation catalyst. [Prior Art] When a photocatalytic reaction is performed by irradiating ultraviolet rays to a solid compound having photocatalytic properties, a hole (positive hole: hole) which excites electrons and electrons to leave is generated, and the excited electron system has a reducing action, and the positive electric current The cave system has a strong oxidation effect by which the reaction of the reactants is oxidized or reduced. A solid compound which is representative of photocatalytic properties is titanium oxide. When the titanium oxide system absorbs ultraviolet rays, it can exert a strong oxidation action. For example, it has been used in a wide range of applications such as air purification, water purification, pollution prevention, deodorization, antibacterial, hospital infection prevention, and anti-fog. The main crystal form of titanium oxide is conventionally known as rutile and anatase. In comparison with the amorphous titanium oxide (amorphous), these crystalline titanium oxides exhibit high chemical stability and a large refractive index. Further, it is known that titanium oxide particles having a high crystallinity can exhibit excellent photocatalytic performance as compared with titanium oxide powder having a low degree of crystallinity, and the larger the crystal size, the more excellent the photocatalytic performance. Patent Document 1 describes a method in which titanium oxide is subjected to alkaline hydrogen peroxide water treatment, sulfuric acid treatment, or hydrofluoric acid treatment to produce a titanium oxide crystal having a novel crystal surface, and the obtained novel crystal surface is also described. The photocatalyst system made of titanium oxide has high oxidation catalyst properties. The titanium oxide of the new 201141609 crystalline surface has been revealed: (1) a novel (1 2 1 ) surface titanium oxide crystal obtained from rutile titanium oxide, and (2) a rutile titanium oxide. The performance is novel (〇〇1) (121) (〇21) (010) titanium oxide crystals on the surface, (3) titanium oxide crystals with novel (02 1) surface obtained from rutile-type titanium oxide, (4) a novel (120) surface titanium oxide crystal obtained from anatase titanium oxide, (5) a novel (1 22) surface titanium oxide crystal obtained from anatase titanium oxide, (6) A titanium oxide crystal having a novel (1 1 2 ) surface obtained from anatase type titanium oxide. Further, in Patent Document 2, it is described that a titanium compound is hydrolyzed at a temperature of 150 ° C or higher and a pressure higher than a saturated vapor pressure at the temperature, and an anatase type and a rutile type are mixed. The titanium oxide can obtain fine particle titanium oxide having a high crystallinity and a uniform particle diameter, and the composition ratio of the anatase type to the rutile type can be easily controlled by adjusting the concentration of the titanium compound. However, the rutile-type titanium oxide obtained by the above-described production method is not sufficiently satisfied from the viewpoint of photocatalytic performance. Namely, the present invention has not found a method for producing rutile-type titanium oxide having a photocatalytic activity which can be sufficiently satisfied. [Prior Art Document] [Patent Document] Patent Document: Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. It is an object of the invention to provide a method for producing rutile-type titanium oxide having high photocatalytic activity. [Means for Solving the Problems] As a result of intensive investigations in order to solve the above problems, the present inventors have found that it is generally possible to carry out hydrothermal treatment of a trivalent titanium compound such as titanium trichloride in an aqueous medium. a rod-shaped rutile-type titanium oxide having a crystal face (11 〇) (111), but when a tetravalent titanium compound is subjected to a hydrothermal treatment for a specific period of time at a specific temperature and pressure, a crystal face (00 1 ) can be obtained. ( 1 1 0 ) ( 1 1 1 ) rod-shaped rutile-type titanium oxide (see Fig. 1), and rod-shaped rutile-type oxidation having the obtained crystal face (〇〇1) (110) (111) Titanium exhibits excellent photocatalytic properties. The present invention is based on the findings of such findings. That is, the present invention provides a method for producing rutile-type titanium oxide, which is characterized by being subjected to a reaction temperature of from 10 ° C to 220 ° C at a pressure above the saturated vapor pressure in the reaction temperature. The tetravalent titanium compound is subjected to hydrothermal treatment for 2 hours or more in an aqueous medium to obtain a rod-shaped rutile-type titanium oxide having a crystal face (001) (110) (111). The tetravalent titanium compound is preferably titanium tetrachloride. Further, the concentration of the tetravalent titanium compound in the aqueous medium is preferably adjusted to be in the range of 1.5 to 17.0% by weight (in terms of titanium). Further, it is preferred to carry out the above-mentioned 201141609 rod by the cross-flow method. The membrane filtration operation of the rutile-type titanium oxide, in particular, the rod-shaped rutile-type titanium oxide is a rod-shaped rutile-type titanium oxide aqueous dispersion having a concentration of 〇.丨 to 40% by weight by a cross-flow method. Membrane filtration, obtaining a rod-shaped rutile-type titanium oxide aqueous dispersion concentrated by removing ionic impurities from the permeate, and adding water to the concentrated rod-shaped rutile-type titanium oxide aqueous dispersion The rutile-type titanium oxide concentration is diluted to the above range. It is preferable to re-clean the filter membrane periodically while refining the rod-shaped rutile-type titanium oxide by a membrane filtration operation by a cross-flow method. [Effects of the Invention] According to the method for producing rutile-type titanium oxide according to the present invention, it is possible to efficiently synthesize a crystallized surface by performing hydrothermal treatment of a tetravalent titanium compound in an aqueous medium under specific conditions. 1) Rod-shaped rutile-type titanium oxide. According to the method for producing rutile-type titanium oxide according to the present invention, since an inexpensive raw material such as titanium tetrachloride can be used, the cost can be significantly reduced. Further, in general, the rod-shaped rutile type is composed of a crystal face (1 1 0 ) and (1 1 1 ), and the crystal face (1 1 0) functions as a reduction site, and the crystal face (1 1 1) functions as an oxidation site. The rod-shaped rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the present invention has a crystal face (0 0 1 in addition to the crystal face (1 1 0 ) (1 1 1 ). ), since the crystal plane (1 1 0) functions as a reduction site, and the crystal faces (00 1 ) and (1 1 1 ) act as oxidation sites, the excitation electrons generated by irradiation of ultraviolet rays are further enhanced and activated. Separate structure of positive holes. Therefore, 201141609 can exert strong oxidation. When the rod-shaped rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the present invention is used as a photocatalyst, it is effective for oxidizing organic substances, and is used for purification, deodorization, and purification of air. , antibacterial, anti-fouling, etc. [Embodiment] [Formation for Carrying Out the Invention] A method for producing a rutile-type titanium oxide according to the present invention is characterized in that it is saturated vapor at a reaction temperature of from 10 ° C to 220 ° C at the reaction temperature. Under the pressure above the pressure, the tetravalent titanium compound is subjected to hydrothermal treatment for 2 hours or more in an aqueous medium to obtain a rod-shaped rutile-type titanium oxide having a crystal face (00 丨) (11 〇) (1 1 1 ). . (Tetravalent Titanium Compound) For example, the tetravalent titanium compound in the present invention may, for example, be a compound represented by the following formula (1).
Ti ( OR ) ,X4.> ( 1 ) (式中，R係表示烴基，X係表示鹵素原子，t係表示 〇至3之整數）。 R中之烴基’例如，可舉例：甲基、乙基、丙基、異 丙基、正丁基、二級丁基、三級丁基等之Cl.4脂肪族烴基 等。 X中之鹵素原子可舉例：氯、溴、碘等。 如此之4價欽化合物，例如，可舉例：τ i c 14、T i B r 4、 Til<t 等之四 _ 化欽：Ti(0CH3) Ch、Ti(〇C2H5) CI3、Ti 201141609 (OC4H9) Cl3、Ti ( 〇C2H5) Bn、Ti ( OC4H9) Bn 等之三鹵 化院氧基鈦；Ti ( OCH3) 2ci2、Ti ( OCD 2C12、Ti ( OCNHO 2Ch、Ti(〇C2H5) 2Br2 等之二鹵化二烷氧基鈦；Ti(〇cH3) 3CI ' Ti ( 〇C2H5) jCI ' Ti ( OC4H9) 3CI ' Ti ( OC2H5) 3Br ^ 之單鹵化三烷氧基鈦等。於本發明中，其中，基於廉價、 容易取得之觀點，較佳爲四鹵化鈦，特佳爲四氯化鈦 (TiCh )。 (水性介質） 於本發明中，用於水熱處理之際的水性介質，例如， 可舉例：水或是水與水溶性有機溶劑之混合液等。該水溶 性有機溶劑，例如，可舉例：甲醇、乙醇等之醇；乙二醇 二甲基醚等之醚；丙酮等之酮；乙腈等之腈；醋酸等之羧 酸等。 使用水與水溶性有機溶劑的混合液之情形的水與水溶 性有機溶劑之比率係前者/後者（重量比）=10/90至 99.9/0.01，較佳爲50/50至99/1左右。於本發明中，其中， 基於不需要有機溶劑之回收作業之觀點，較佳爲使用水。 另外，也可以將鹵化物（例如，氯化鈉、氯化鉀、、 氯化鋰、溴化鈉、溴化鉀、溴化鋰等之鹼金屬鹵化物等） 添加於水性介質中。但是，於本發明中，尤其，即使未添 加鹵化物，也能夠獲得高的結晶度、粒徑一致的桿狀金紅 石型氧化鈦。 水性介質中之4價鈦化合物濃度（鈦換算）較佳成爲 201141609 1.5至17.0重量％ (較佳爲2.5至15.0重量％，特佳爲2.5 至8 · 0重量％ )之濃度。若水性介質中之4價鈦化合物濃 度（鈦換算）超過上述範圍時，因副產生的氯而反應器有 變容易腐蝕的傾向，另一方面，若水性介質中之4價鈦化. 合物濃度（鈦換算）低於上述範圍時，由反應所獲得之氧 化鈦中混合結晶型不同者而具有結晶型之均一性降低的傾 向。 水熱處理時之反應溫度爲1 10°C至22(TC，較佳爲140°C 至220°C，特佳爲150°C至220°C。若水熱處理時之反應溫 度超過上述範圍時，由副產生的氯而具有反應器變得容易 腐蝕，另一方面，若水熱處理時之反應溫度低於上述範圍 時，未形成結晶面（001 )。 水熱處理係在反應溫度之飽和蒸氣壓以上的壓力下 (亦即，於密閉系中）進行。水熱處理時之反應壓力（絕 對壓力）例如爲0.14 MPa至1.6 MPa，較佳爲0.36 MPa至 1.6 MPa，特佳爲 0.48 MPa 至 1.6 MPa。 另外，實施水熱處理之時間爲2小時以上（例如，2 小時至24小時，較佳爲2小時至15小時，特佳爲5小時 至1 5小時）。若實施水熱處理之時間過長時，具有生產性 將降低之傾向。另一方面，若實施水熱處理之時間低於上 述範圍時，則未形成結晶面（〇〇 1 )。 本發明中之水熱處理能夠利用分批式、半分批式、連 續式等之習用方法而進行，例如，藉由使用高壓釜等之密 -10- 201141609 閉系反應容器’且將反應溫度、反應壓力、反應時間、及 必要時之水性介質中之4價鈦化合物濃度（鈦換算）調整 至上述範圍而能夠進行。 利用_h述方法所獲得之桿狀金紅石型氧化鈦係藉由組 合例如過濾、濃縮、蒸餾、萃取、結晶析出、再結晶、管 柱層析等之分離手段，或組合此等之分離手段而能夠分離 精製。 於本發明中，其中，基於不密壓化桿狀金紅石型氧化 鈦而能夠分離/去除離子性不純物之觀點，較佳爲對桿狀金 紅石型氧化鈦水分散液實施藉由交叉流動方式所進行的膜 過濾之操作。所謂藉由交叉流動方式所進行的膜過濾之操 作係將供應液平行流向濾膜面，一邊防止因濾渣之沉降所 造成的濾膜污染，且一邊在供應液之流動側面而將供應液 之一部分作爲透過水，進行分離/去除而獲得濃縮液之方 法。藉由交叉流動方式而膜過濾桿狀金紅石型氧化鈦水分 散液時，能夠減低離子性不純物之含量，且既簡便又效率 佳地獲得具有高分散性之桿狀金紅石型氧化鈦。 藉由交叉流動方式所進行的膜過濾中之濃縮倍率較佳 約爲1至400倍左右（其中，1至20倍，特佳爲1至10倍）。 若濃縮倍率超過上述範圍時，具有對膜面之附著物質的堆 積抑制將變得困難，過濾速度及膜壽命有變得容易降低之 傾向。另一方面，若濃縮倍率低於上述範圍時’具有離子 性不純物之分離效率將降低、洗淨水之用量將增加之傾向。 -11 - 201141609 藉由交叉流動方式所進行的膜過濾中之濃縮 藉由桿狀金紅石型氧化鈦水分散液之膜面線速度 動速度）而調整。因爲含有桿狀金紅石型氧化鈦 之供應液的膜面線速度越大，越能夠抑制對膜面 質的堆積而可以獲得高的過濾通量，例如，膜面線 叉流動速度）例如0.02 m/s以上、低於3 m/s ,較 m/s以上、低於1.5 m/s。 就交付藉由交叉流動方式而作膜過濾之操作 紅石型氧化鈦水分散液而言，較佳爲使用利用水 精製水、蒸餾水、純水、離子交換水等）進行稀 狀金紅石型氧化鈦含量成爲例如0.1至40重量％ 佳成爲0.1至20重量％左右。若桿狀金紅石型氧 脫離上述範圍時，將有離子性不純物之去除效率 傾向。另外，桿狀金紅石型氧化欽含量超過上述 形，也將有黏度變得過高、變得容易阻塞（堵塞） 而且，藉由膜過濾處理，由於水與離子性不純物 透過液而被分離，例如可以獲得濃縮成1至400倍 中，1至20倍，尤其1至10倍）的桿狀金紅石型 分散液。 於本發明中，重複進行藉由上述交叉流動方 濾之操作，基於能夠充分地分離/去除離子性不, 點，故較佳。較佳爲藉由利用水（例如，精製水、 純水、離子交換水等）稀釋依照交叉流動方式所 倍率能夠 (交叉流 水分散液 之附著物 速度（交 佳爲0 · 0 5 的桿狀金 (例如， 釋任一桿 左右，較 化鈦含量 將降低之 範圍之情 之傾向。 一倂作爲 :左右（其 氧化鈦水 式而膜過 純物之觀 蒸餾水、 進行的膜 -12- 201141609 過濾所獲得之所濃縮的桿狀金紅石型氧化鈦水分散液，將 桿狀金紅石型氧化鈦水分散液之濃度調整至上述範圍，之 後，再度交付膜過濾處理。藉此，能夠使離子性不純物之 分離效率提高，而且能夠減輕因阻塞（堵塞）等所造成的 濾膜之負荷、使濾膜之壽命提高。 因而’於本發明中，尤其藉由交叉流動方式而膜過濾 桿狀金紅石型氧化鈦濃度爲0.1至40重量％左右，較佳爲 0.1至20重量％左右之桿狀金紅石型氧化鈦水分散液，與 透過液一併分離去除離子性不純物而獲得所濃縮之桿狀金 紅石型氧化鈦水分散液，將水加入該所濃縮之桿狀金紅石 型氧化鈦水分散液中，使桿狀金紅石型氧化鈦濃度成爲上 述範圍的方式來稀釋，藉由再度重複操作藉由交叉流動方 式而膜過濾的循環膜過濾方式來精製桿狀金紅石型氧化 鈦’同時也定期地逆洗淨濾膜，基於提高離子性不純物之 分離效率、抑制與此同時對膜面的附著物質堆積、提高膜 壽命之觀點，故較佳。 第2圖係顯示藉由金紅石型氧化鈦之循環膜過濾方式 所進行的精製方法之一例的槪略圖。含有進料槽中所進料 的桿狀金紅石型氧化鈦水分散液的供應液係以交叉流動過 濾方式予以膜過濾’ ·可以獲得所濃縮的桿狀金紅石型氧化 鈦水分散液（濃縮液）。所濃縮的桿狀金紅石型氧化鈦水 分散液再度循環至進料槽，以稀釋用之水（稀釋用水）予 以稀釋’再度以交叉流動方式而予以膜過濾。 -13- 201141609 上述離子性不純物，例如，可舉例：源自成爲原料之 4價鈦化合物之鈦離子、鹵素離子（例如，氯離子，、溴離 子、碘離子）等。 於本發明中’於桿狀金紅石型氧化鈦中所含之離子性 不純物量’例如，較佳爲減低直到1 〇至3000 ppm左右（較 佳爲10至200 0 ppm左右）。若桿狀金紅石型氧化鈦中所 含之離子性不純物之含量減低至上述範圍時，能夠提高桿 狀金紅石型氧化鈦之對光的應答性。 上述濾膜’例如，可舉例：超濾膜、精密濾膜、奈米 濾膜、逆滲透膜等。於本發明中，其中，基於示差分子量 之觀點，較佳爲使用超濾膜。 超濾膜係孔尺寸爲1至10 nm(較佳爲1至5 nm)， 以分子量1000至300000之物質（分子尺寸爲0.001至0.01 μιη左右）〔較佳爲分子量1〇〇〇至30000 (作成分子尺寸爲 1至5 nm)〕作爲分離對象的分離膜。 超濾膜之膜形式，例如，也可以爲中空絲型濾膜、管 型膜、螺旋型膜、平膜等中任一種，但基於逆洗淨較容易 進行之觀點，較佳爲使用中空絲型濾膜或螺旋型膜。 從防止污染物質閉塞、提高對膜P組之中空絲塡充率 之觀點，中空絲型濾膜中之中空絲膜之內徑較佳爲〇. 1至 2_0 mm左右之範圍，進一步較佳爲0.5至l.〇mm之範圍。 瀘膜之材質可使用一般之物，例如醋酸纖維素、聚丙 烯腈、聚颯、聚醚颯、芳香族聚醯胺、聚偏氟乙烯、聚氯 -14- 201141609 乙烯、聚乙烯、聚丙烯、聚醯亞胺、陶瓷等。此等之中， 濾膜之材質較佳爲醋酸纖維素、聚颯、聚醚颯（PES)、聚 丙烯腈、芳香族聚醯胺。 中空絲膜可舉例：醋酸纖維素系中空絲膜、聚颯系中 空絲膜、聚丙烯腈系中空絲膜、聚偏氟乙烯中空絲膜等。 此等之中’由於對酸之承受性高，較佳爲聚颯系中空絲膜。 使用中空絲型濾膜之情形，流通桿狀金紅石型氧化鈦 水分散液之方法（過濾方式）可舉例：將含有桿狀金紅石 型氧化鈦水分散液之供應液流入內側（中空絲膜之內側）， 將透過水流入外側（中空絲膜之外側）的方式（內壓過濾 方式）：與相反地，將含有桿狀金紅石型氧化鈦水分散液 之供應液流入外側，使透過水流向內側的方式（外壓過濾 方式）。於本發明中’其中，基於能夠維持膜面流速高之 觀點，較佳爲內壓過濾方式。 實施藉由交叉流動方式而膜過濾之操作之際係用以防 止對濾膜面之附著物質的堆積、減輕對濾膜之負擔、進行 長期間膜過濾運轉’較佳爲藉由洗淨水而對濾膜實施間歇 性之逆洗淨。逆洗淨較佳爲一邊控制壓力且一邊以所預定 的周期進行’例如，在0.5至3小時進行1次左右。逆洗 淨之時間較佳爲0.5至2分鐘左右。此時，過濾回收率可 以設定爲90%以上’更佳設定爲95%以上。過濾回收率係 以下式（2 )所代表。 過濾回收率（％) =100x(膜過濾流量—逆洗淨水量） -15- 201141609 /膜過濾流量 （2 ) 還有，用於逆洗淨之洗淨水較佳爲使用水（例如，精 製水、蒸餾水、純水、離子交換水等）。另外，藉由逆洗 淨而通過膜之洗淨水較佳作爲所濃縮的桿狀金紅石型氧化 鈦水分散液之稀釋用水而再利用（參閱第3圖）。 於藉由交叉流動方式而膜過濾之操作中，藉由監視透 過液之pH而能夠容易地確認離子性不純物之去除處理的 進行程度，例如，較佳爲藉由使透過液之pH成爲2至7(較 佳爲2至5)爲止，重複藉由交叉流動方式而膜過濾之操 作。透過液之pH超過上述範圍之情形，具有離子性不純物 之去除處理爲不充分之情形。 由於藉由關於本發明申請案之金紅石型氧化鈦之製造 方法所獲得之桿狀金紅石型氧化鈦係具有結晶面（00 1 ) (1 1 0 )( 1 1 1 )，能夠抑制激發電子與正電洞之再結合， 且能夠更進一步抑制逆反應之進行。藉此，由於能夠發揮 高的光觸媒活性，能夠對各種化學反應（例如，氧化反應、 有害物質之分解反應等）或殺菌等，作爲光觸媒利用。 利用關於本發明之金紅石型氧化鈦之製造方法所獲得 之桿狀金紅石型氧化鈦係藉由照射低於3 80 nm之紫外線 (根據桿狀金紅石型氧化鈦之種類，藉由照射從紫外線區 域直到650nm左右之長波長的可見光線區域爲止之廣波長 範圍內之光）而能夠發揮高的觸媒活性。 由於利用關於本發明之金紅石型氧化鈦之製造方法所 -16 - 201141609 由於利用關於本發明之金紅石型氧化鈦之製造方法所 獲得之桿狀金紅石型氧化鈦係藉由上述光之照射而能夠將 有害化學物質分解成水或二氧化碳爲止，能夠應甩至抗菌 防霉、除臭、空氣淨化、水質淨化、防污等各式各樣，以 室內之壁紙或家具爲主’並能夠應用至在家庭內或醫院、 學校等之公共設施內之環境淨化、家電製品之高機能化等 之廣範圍。 〔實施例〕 以下，藉由實施例而更具體說明本發明，但本發明並 不受此等實施例所限定。 實施例1 在室溫（25°C )，使Ti濃度成爲5.4重量％的方式來 利用離子交換水稀釋市售的T i C11水溶液（和光純藥公司製 試藥化學用’含有約16.5%Ti之稀鹽酸溶液）。將此稀釋 後之TiCh水溶液56 g加入塗裝有特夫綸（Teflon，註冊商 標）之容量l〇〇ml之高壓釜內而密閉。將上述高壓釜投入 油浴中’經歷.30分鐘而將在高壓釜內之TiCh水溶液的溫 度升溫至1 8 0 °C爲止。之後，以反應溫度1 8 〇 t、反應壓力 1 ·〇 MPa之條件下’保持1 〇小時之後，澆淋冰水而冷卻高 壓釜。3分鐘後’確認使高壓釜內之溫度成爲3〇t以下後， 開封高壓釜，取出反應物（1 )。於1 〇 ，離心分離所獲得 之反應物（1 ) ’利用去離子水進行漂洗，於內溫6 5它之真 空乾燥機（真空烘箱）減壓乾燥12小時，獲得5.2 g之氧 -17- 201141609 氧化鈦粒子爲具有結晶面（00 1 ) ( 1 1 0 ) ( 1 1 1 )之桿狀金 紅石型氧化鈦粒子（第4圖）^ 實施例2 除了將反應時間從1 0小時變更成3小時以外，進行相 同於實施例1之方式而獲得4.7 g之氧化欽粒子。 實施例3 除了將反應時間從1 0小時變更成1 4小時以外，進行 相同於實施例1之方式而獲得5.2 g之氧化鈦粒子。 實施例4 除了將反應溫度從1 80°C變更成1 40°C以外，進行柑同 於實施例1之方式而獲得4.9 g之氧化鈦粒子。 實施例5 除了將反應溫度從180°C變更成200°C以外，進行相同 於實施例1之方式而獲得5.2 g之氧化鈦粒子》 實施例6 除了將反應溫度從180°C變更成220°C以外，進行相同 於實施例1之方式而獲得5.2 g之氧化鈦粒子。 實施例7 以純水而將上述實施例1所獲得之反應物（1 ) 56 g稀 釋成 10 倍之後，使用超濾膜（商品名 「FB10-HVC-FUS03C1」、材質：PES、標稱示差分子量：3 萬、Dicel Membrane Systems (股）製），以室溫（25°C )、 過濾壓力0.05 MPa，進行藉由交叉流動方式而膜過濾之操 • 18 - 201141609 作，分離離子性不純物與氧化鈦粒子，將分離離子性不純 物排出至系統外，獲得所精製之氧化鈦粒子水分散液56 g。利用60°C之真空乾燥機而1 2小時乾燥所精製之氧化鈦 粒子水分散液，獲得5.2 g之氧化鈦粒子。 比較例1 除了將反應時間從1 0小時變更成1小時、將反應溫度 從180°C變更成200°C以外，進行相同於實施例1之方式而 獲得4.5 g之氧化鈦粒子。利用穿透式電子顯微鏡（TEM ) 確認所獲得之氧化鈦粒子爲具有結晶面（1 1 0 )( 1 1 1 )之 桿狀金紅石型氧化鈦粒子，結晶面（00 1 )則無法鑑定（第 5圖）。 比較例2 除了將反應溫度從180°C變更成100°C以外，進行相同 於實施例1之方式而獲得4.3 g之氧化鈦粒子。利用穿透式 電子顯微鏡（TEM )確認所獲得之氧化鈦粒子爲具有結晶 面（1 1 0 )( 1 1 1 )之桿狀金紅石型氧化鈦粒子，結晶面（00 1 ) 則無法鑑定。 <光觸媒活性評估> 在氣相中氧化乙醛，測定所生成的C〇2量而評估實施 例1至7及比較例1、2所獲得之氧化鈦粒子之光觸媒性能。 藉由將Tedlar bag (取樣袋）（As〇ne (股）公司製） 作爲反應容器使用。分別將實施例1至7及比較例1、2所 獲得之氧化鈦粒子1 00 mg展開於玻璃製皿上，置入反應容 -19- 201141609 獲得之氧化鈦粒子1 〇〇 mg展開於玻璃製皿上，置入反應容 器之中，將500 ppm之乙醛飽和氣體注入反應容器中。氣 體與乙醛達到平衡後，於室溫（)進行光照射。光源 中使用500 W之氙燈用光源裝置（商品名「SX-UI501XQ」、 Ushio電機（股）製），並使用UV-35濾浓器而遮斷較350 nm爲短的波長之光線。進一步將精細不銹鋼製之篩作爲光 量調節用濾波器使用，將光量調整至30 mW/cm2。 使用裝設有甲烷化器之氫火燄離子化檢測器之氣相層 析儀（商品名「GC-8A」、「GC-14A」、島津製作所製） 而測定從光照射開始至150分鐘後之C〇2生成量（反應容 器內之C〇2濃度）。 將上述光觸媒活性評估結果彙整而顯示於下表中。 〔表1〕 實施例 1 實施例 2 實施例 3 實施例 4 實施例 5 實施例 6 實施例 7 比較例 1 比較例 2 ca濃度 (ppm) 520 315 477 338 510 450 542 153 149 由以上結果，得知利用有關本發明之金紅石型氧化鈦 之製造方法所獲得之金紅石型氧化鈦係一種具有結晶面 (00 1 )( 1 1 0 )( 1 1 1 )之桿狀金紅石型氧化鈦，能夠發揮 優異的光觸媒性能，且能夠發揮有機化合物之優異的氧 化、分解作用。 〔產業上利用之可能性〕 若將利用關於本發明之金紅石型氧化鈦之製造方法所 -20- 201141609 獲得之桿狀金紅石型氧化纟太作爲光觸媒使用時’由於能夠 效率佳地氧化有機物質’而有用於空氣之淨化、除臭、淨 水、抗菌、防污等之目的。 【圖式簡單說明】 第1圖係示意表示水熱處理3價鈦化合物所獲得之結 晶、與在特定條件下水熱處理4價鈦化合物所獲得之結晶 的模示圖。 第2圖係顯示藉由金紅石型氧化鈦之循環膜過濾方式 所進行的精製方法之一例的槪略圖。 第3圖係顯示藉由金紅石型氧化鈦之循環膜過濾方式 所進行的精製方法中之逆洗淨方法之—例的槪略圖。 第4圖係顯示在實施例1所獲得之金紅石型氧化鈦之 TEM照片。 第5圖係顯示在比較例1所獲得之金紅石型氧化鈦之 TEM照片。 【主要元件符號說明】 (001 ) 結晶面 (110) 結晶面 (111 ) 結晶面 -21-Ti (OR ) , X4. (1) (wherein R represents a hydrocarbon group, X represents a halogen atom, and t represents an integer of 〇 to 3). The hydrocarbon group in R may, for example, be a Cl. 4 aliphatic hydrocarbon group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, a secondary butyl group or a tertiary butyl group. The halogen atom in X can be exemplified by chlorine, bromine, iodine, and the like. Such a tetravalent compound, for example, may be exemplified by: τ ic 14, T i B r 4, Til <t, etc. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Trihalogenated titanium oxide of Cl3, Ti (〇C2H5) Bn, Ti (OC4H9) Bn, etc.; dihalogenated titanium of Ti(OCH3) 2ci2, Ti ( OCD 2C12, Ti ( OCNHO 2Ch, Ti(〇C2H5) 2Br2 , etc. Titanium alkoxide; Ti(〇cH3) 3CI 'Ti (〇C2H5) jCI 'Ti (OC4H9) 3CI 'Ti(OC2H5) 3Br ^ monohalogenated trialkoxy titanium, etc. In the present invention, among them, based on inexpensive The viewpoint of easy availability is preferably titanium tetrahalide, particularly preferably titanium tetrachloride (TiCh). (Aqueous medium) In the present invention, an aqueous medium used for hydrothermal treatment, for example, water or The water-soluble organic solvent is, for example, an alcohol such as methanol or ethanol; an ether such as ethylene glycol dimethyl ether; a ketone such as acetone; and a nitrile such as acetonitrile. a carboxylic acid such as acetic acid, etc. The ratio of water to a water-soluble organic solvent in the case of using a mixture of water and a water-soluble organic solvent is the former/the latter (heavy The ratio is from 10/90 to 99.9/0.01, preferably from about 50/50 to about 99/1. In the present invention, it is preferred to use water based on the viewpoint of a recovery operation which does not require an organic solvent. A halide (for example, an alkali metal halide such as sodium chloride, potassium chloride, lithium chloride, sodium bromide, potassium bromide or lithium bromide) may be added to the aqueous medium. However, in the present invention In particular, even if a halide is not added, a rod-shaped rutile-type titanium oxide having a high crystallinity and a uniform particle diameter can be obtained. The concentration of the tetravalent titanium compound in the aqueous medium (in terms of titanium) is preferably 201141609 1.5 to 17.0 by weight. The concentration of % (preferably 2.5 to 15.0% by weight, particularly preferably 2.5 to 8.0 % by weight). If the concentration of the tetravalent titanium compound in the aqueous medium (in terms of titanium) exceeds the above range, In the case where the concentration of the tetravalent titanium compound in the aqueous medium (in terms of titanium) is less than the above range, the mixed crystal form of the titanium oxide obtained by the reaction is different. Pour with reduced uniformity of crystalline form The reaction temperature in the hydrothermal treatment is from 1 10 ° C to 22 (TC, preferably from 140 ° C to 220 ° C, particularly preferably from 150 ° C to 220 ° C. If the reaction temperature in the hydrothermal treatment exceeds the above range The chlorine generated by the by-product causes the reactor to be easily corroded. On the other hand, when the reaction temperature in the hydrothermal treatment is lower than the above range, the crystal face (001) is not formed. The hydrothermal treatment is carried out at a pressure equal to or higher than the saturated vapor pressure of the reaction temperature (i.e., in a closed system). The reaction pressure (absolute pressure) at the time of hydrothermal treatment is, for example, 0.14 MPa to 1.6 MPa, preferably 0.36 MPa to 1.6 MPa, and particularly preferably 0.48 MPa to 1.6 MPa. Further, the time for performing the hydrothermal treatment is 2 hours or longer (for example, 2 hours to 24 hours, preferably 2 hours to 15 hours, particularly preferably 5 hours to 15 hours). If the time for performing the hydrothermal treatment is too long, the productivity tends to be lowered. On the other hand, when the time for performing the hydrothermal treatment is lower than the above range, the crystal face (〇〇 1 ) is not formed. The hydrothermal treatment in the present invention can be carried out by a conventional method such as a batch type, a semi-batch type, or a continuous type, for example, by using a closed-loop reaction vessel of an autoclave or the like and the reaction temperature and reaction are carried out. The pressure, the reaction time, and, if necessary, the concentration of the tetravalent titanium compound in the aqueous medium (in terms of titanium) can be adjusted to the above range. The rod-shaped rutile-type titanium oxide obtained by the method described by _h is a separation means by combining, for example, filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography, or the like, or a combination thereof. It can be separated and refined. In the present invention, it is preferable to carry out the cross flow method for the rod-shaped rutile-type titanium oxide aqueous dispersion from the viewpoint of being capable of separating/removing ionic impurities without densely pressing the rod-shaped rutile-type titanium oxide. The membrane filtration operation performed. The membrane filtration operation by the cross-flow method is to supply the supply liquid in parallel to the filter membrane surface, while preventing the membrane fouling caused by the sedimentation of the filter residue, and one part of the supply liquid on the flow side of the supply liquid. As a method of obtaining a concentrated liquid by separating/removing through water. When the rod-shaped rutile-type titanium oxide moisture dispersion is membrane-filtered by the cross-flow method, the content of the ionic impurities can be reduced, and the rod-shaped rutile-type titanium oxide having high dispersibility can be obtained simply and efficiently. The concentration ratio in the membrane filtration by the cross-flow method is preferably about 1 to 400 times (1 to 20 times, particularly preferably 1 to 10 times). When the concentration ratio exceeds the above range, it is difficult to suppress the deposition of the adhering substance on the film surface, and the filtration speed and the film life tend to be lowered. On the other hand, when the concentration ratio is lower than the above range, the separation efficiency with ionic impurities is lowered, and the amount of washing water tends to increase. -11 - 201141609 Concentration in membrane filtration by cross-flow method is adjusted by the membrane surface linear velocity of the rod-shaped rutile-type titanium oxide aqueous dispersion. Since the film surface speed of the supply liquid containing the rod-shaped rutile-type titanium oxide is larger, the deposition of the film surface quality can be suppressed, and a high filtration flux can be obtained, for example, the film surface line flow velocity), for example, 0.02 m. Above /s, below 3 m/s, above m/s, below 1.5 m/s. It is preferable to use a water-refined water, distilled water, pure water, ion-exchanged water or the like to carry out a thin rutile-type titanium oxide in the operation of a redstone-type titanium oxide aqueous dispersion which is subjected to membrane filtration by a cross-flow method. The content is, for example, 0.1 to 40% by weight, preferably about 0.1 to 20% by weight. When the rod-shaped rutile-type oxygen deviates from the above range, the removal efficiency of the ionic impurities tends to be high. In addition, when the content of the rod-shaped rutile-type oxidized sulphur exceeds the above-mentioned shape, the viscosity becomes too high, and it becomes easy to block (clogging), and is separated by the membrane filtration treatment due to the permeation of water and ionic impurities. For example, a rod-shaped rutile-type dispersion which is concentrated to be 1 to 400 times, 1 to 20 times, particularly 1 to 10 times, can be obtained. In the present invention, the operation by the above-described cross-flow filtration is repeated, and it is preferable because the ionicity is not sufficiently separated and removed. It is preferable to use a water (for example, purified water, pure water, ion-exchanged water, etc.) to dilute the ratio according to the cross-flow method (the velocity of the cross-flow aqueous dispersion (the cross-shaped water is 0·0 5 of the rod-shaped gold) (For example, the tendency to release the rod to the left or right, the titanium content will be reduced. One 倂 as: about the titanium oxide water type and the membrane is purely distilled water, the membrane is carried out-12- 201141609 Filtration The concentration of the rod-shaped rutile-type titanium oxide aqueous dispersion obtained in the obtained rod-shaped rutile-type titanium oxide aqueous dispersion is adjusted to the above range, and then the membrane filtration treatment is again carried out, whereby ionicity can be obtained. The separation efficiency of the impurities is improved, and the load of the filter due to clogging (clogging) or the like can be reduced, and the life of the filter can be improved. Thus, in the present invention, the membrane-like rutile is especially filtered by a cross-flow method. The rod-shaped rutile-type titanium oxide aqueous dispersion having a concentration of titanium oxide of about 0.1 to 40% by weight, preferably about 0.1 to 20% by weight, is separated from the permeate to remove ionicity. Obtaining a concentrated rod-shaped rutile-type titanium oxide aqueous dispersion, and adding water to the concentrated rod-shaped rutile-type titanium oxide aqueous dispersion to make the rod-shaped rutile-type titanium oxide concentration into the above range By diluting, the rod-shaped rutile-type titanium oxide is replenished by a cyclic membrane filtration method of membrane filtration by a cross-flow method, and the filter membrane is also periodically washed back, based on improving the separation efficiency of the ionic impurities, It is preferable to suppress the deposition of the adhering substance on the film surface and to improve the film life. Fig. 2 is a schematic view showing an example of a purification method by a circulating membrane filtration method of rutile-type titanium oxide. The supply liquid containing the rod-shaped rutile-type titanium oxide aqueous dispersion fed in the feed tank is subjected to membrane filtration by cross-flow filtration method. · The concentrated rod-shaped rutile-type titanium oxide aqueous dispersion can be obtained (concentrated Liquid). The concentrated rod-shaped rutile-type titanium oxide aqueous dispersion is recycled to the feed tank again, and diluted with dilution water (diluted water). In the above-mentioned ionic impurities, for example, titanium ions derived from a tetravalent titanium compound which is a raw material, halogen ions (for example, chloride ions, bromide ions, iodide ions), etc., may be exemplified. In the present invention, 'the amount of ionic impurities contained in the rod-shaped rutile-type titanium oxide' is, for example, preferably reduced to about 1 〇 to about 3000 ppm (preferably about 10 to 200 0 ppm). When the content of the ionic impurities contained in the rutile-type titanium oxide is reduced to the above range, the responsiveness of the rod-shaped rutile-type titanium oxide to light can be improved. For example, the filter membrane can be, for example, an ultrafiltration membrane. A microfiltration membrane, a nanofiltration membrane, a reverse osmosis membrane, etc. In the present invention, an ultrafiltration membrane is preferably used from the viewpoint of the molecular weight difference. The ultrafiltration membrane has a pore size of 1 to 10 nm (preferably 1 to 5 nm) and a molecular weight of 1,000 to 300,000 (molecular size of about 0.001 to 0.01 μm) (preferably a molecular weight of 1 to 30000 ( As a separation membrane having a component size of 1 to 5 nm) as a separation object. The membrane form of the ultrafiltration membrane may be, for example, any one of a hollow fiber membrane, a tubular membrane, a spiral membrane, and a flat membrane. However, it is preferred to use a hollow filament from the viewpoint that the reverse washing is easier to carry out. Type filter or spiral membrane. The inner diameter of the hollow fiber membrane in the hollow fiber type filter membrane is preferably in the range of about 1 to 2_0 mm, more preferably from the viewpoint of preventing clogging of the contaminant and increasing the hollow fiber charge rate of the membrane P group. 0.5 to l. 〇 mm range. The material of the ruthenium film can be used in general, such as cellulose acetate, polyacrylonitrile, polyfluorene, polyether oxime, aromatic polyamine, polyvinylidene fluoride, polychloro-14- 201141609 ethylene, polyethylene, polypropylene , polyimine, ceramics, etc. Among these, the material of the filter membrane is preferably cellulose acetate, polyfluorene, polyether oxime (PES), polyacrylonitrile, or aromatic polyamine. Examples of the hollow fiber membrane include a cellulose acetate hollow fiber membrane, a polyfluorene hollow fiber membrane, a polyacrylonitrile hollow fiber membrane, and a polyvinylidene fluoride hollow fiber membrane. Among these, it is preferably a polyfluorene hollow fiber membrane because of its high acceptability to acid. In the case of using a hollow fiber type filter, the method of filtering the rod-shaped rutile-type titanium oxide aqueous dispersion (filtration method) can be exemplified by flowing a supply liquid containing a rod-shaped rutile-type titanium oxide aqueous dispersion into the inside (hollow fiber membrane) (inside), a method in which the permeated water flows into the outside (the outer side of the hollow fiber membrane) (internal pressure filtration method): Conversely, the supply liquid containing the rod-shaped rutile-type titanium oxide aqueous dispersion flows into the outside to make the permeated water The way to the inside (external pressure filtration). In the present invention, the internal pressure filtration method is preferred from the viewpoint of maintaining a high flow velocity of the membrane surface. When performing the membrane filtration operation by the cross-flow method, it is preferable to prevent the deposition of the adhering substance to the filter surface, reduce the burden on the filter membrane, and perform the long-term membrane filtration operation. The filter was subjected to intermittent backwashing. The backwashing is preferably carried out at a predetermined cycle while controlling the pressure, for example, about once in 0.5 to 3 hours. The time for backwashing is preferably about 0.5 to 2 minutes. At this time, the filtration recovery rate can be set to 90% or more, and more preferably 95% or more. The filtration recovery rate is represented by the following formula (2). Filtration recovery rate (%) = 100x (membrane filtration flow rate - backwash water volume) -15- 201141609 / membrane filtration flow rate (2) Further, it is preferred to use water for the reverse washing of the washing water (for example, refining) Water, distilled water, pure water, ion exchange water, etc.). Further, the washing water which has passed through the membrane by backwashing is preferably reused as the dilution water of the concentrated rod-shaped rutile-type titanium oxide aqueous dispersion (see Fig. 3). In the operation of membrane filtration by the cross-flow method, the progress of the removal treatment of the ionic impurities can be easily confirmed by monitoring the pH of the permeate, and for example, it is preferable to make the pH of the permeate 2 to The operation of membrane filtration by the cross flow method is repeated until 7 (preferably 2 to 5). When the pH of the permeate exceeds the above range, the removal treatment of the ionic impurities is insufficient. Since the rod-shaped rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the application of the present invention has a crystal plane (00 1 ) (1 1 0 ) (1 1 1 ), excitation electrons can be suppressed. It is combined with the positive hole and can further suppress the progress of the reverse reaction. As a result, it is possible to exhibit high photocatalytic activity, and it can be used as a photocatalyst for various chemical reactions (for example, oxidation reaction, decomposition reaction of harmful substances, etc.) or sterilization. The rod-shaped rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the present invention is irradiated with ultraviolet rays of less than 380 nm (according to the type of rod-shaped rutile-type titanium oxide, by irradiation) The ultraviolet light region can exhibit high catalytic activity in light in a wide wavelength range up to a long-wavelength visible light region of about 650 nm. The rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the present invention is irradiated with the above-mentioned light by the method of producing rutile-type titanium oxide according to the present invention. It can decompose harmful chemicals into water or carbon dioxide, and can be applied to various types of indoor wallpapers or furniture, such as antibacterial, mildew, deodorization, air purification, water purification, and antifouling. To a wide range of environmental purification in the public facilities of homes, hospitals, schools, etc., and high functionalization of home appliances. [Examples] Hereinafter, the present invention will be specifically described by way of Examples, but the present invention is not limited by the Examples. Example 1 The commercially available T i C11 aqueous solution was diluted with ion-exchanged water at a room temperature (25 ° C) to have a Ti concentration of 5.4% by weight (the reagent for chemical use by Wako Pure Chemical Industries Co., Ltd.) contained about 16.5% Ti. Diluted hydrochloric acid solution). 56 g of this diluted TiCh aqueous solution was placed in an autoclave having a capacity of 10 ml of Teflon (registered trademark) and sealed. The autoclave was placed in an oil bath and the temperature of the TiCh aqueous solution in the autoclave was raised to 180 °C for 30 minutes. Thereafter, the mixture was kept at a reaction temperature of 1 8 Torr and a reaction pressure of 1 · 〇 MPa for 1 hour, and then ice water was poured to cool the autoclave. After 3 minutes, it was confirmed that the temperature in the autoclave was 3 Torr or less, and the autoclave was opened, and the reactant (1) was taken out. At 1 Torr, the reactant (1) obtained by centrifugation was rinsed with deionized water, and dried under reduced pressure at an internal temperature of 6 5 in a vacuum dryer (vacuum oven) for 12 hours to obtain 5.2 g of oxygen-17- 201141609 Titanium oxide particles are rod-shaped rutile-type titanium oxide particles having a crystal plane (00 1 ) ( 1 1 0 ) (1 1 1 ) (Fig. 4) ^ Example 2 except that the reaction time was changed from 10 hours to 10 hours. Other than 3 hours, 4.7 g of oxidized granules were obtained in the same manner as in Example 1. Example 3 5.2 g of titanium oxide particles were obtained in the same manner as in Example 1 except that the reaction time was changed from 10 hours to 14 hours. Example 4 In the same manner as in Example 1 except that the reaction temperature was changed from 180 °C to 140 °C, 4.9 g of titanium oxide particles were obtained. Example 5 In the same manner as in Example 1, except that the reaction temperature was changed from 180 ° C to 200 ° C, 5.2 g of titanium oxide particles were obtained. Example 6 except that the reaction temperature was changed from 180 ° C to 220 ° Other than C, 5.2 g of titanium oxide particles were obtained in the same manner as in Example 1. Example 7 After diluting 56 g of the reactant (1) obtained in the above Example 1 into 10 times with pure water, an ultrafiltration membrane (trade name "FB10-HVC-FUS03C1", material: PES, nominal deviation) was used. Molecular weight: 30,000, Dicel Membrane Systems (manufactured by Dicel Membrane Systems), at room temperature (25 ° C), filtration pressure 0.05 MPa, membrane filtration by cross-flow method • 18 - 201141609, separation of ionic impurities and The titanium oxide particles were discharged to the outside of the system, and 56 g of the purified aqueous dispersion of titanium oxide particles was obtained. The purified aqueous dispersion of titanium oxide particles was dried by a vacuum dryer at 60 ° C for 12 hours to obtain 5.2 g of titanium oxide particles. Comparative Example 1 4.5 g of titanium oxide particles were obtained in the same manner as in Example 1 except that the reaction time was changed from 10 hours to 1 hour and the reaction temperature was changed from 180 °C to 200 °C. It was confirmed by a transmission electron microscope (TEM) that the obtained titanium oxide particles were rod-shaped rutile-type titanium oxide particles having a crystal face (1 1 0 ) (1 1 1 ), and the crystal face (00 1 ) could not be identified ( Figure 5). Comparative Example 2 4.3 g of titanium oxide particles were obtained in the same manner as in Example 1 except that the reaction temperature was changed from 180 °C to 100 °C. It was confirmed by a transmission electron microscope (TEM) that the obtained titanium oxide particles were rod-shaped rutile-type titanium oxide particles having a crystal face (1 1 0 ) (1 1 1 ), and the crystal face (00 1 ) could not be identified. <Photocatalyst Activity Evaluation> The photocatalytic performance of the titanium oxide particles obtained in Examples 1 to 7 and Comparative Examples 1 and 2 was evaluated by oxidizing acetaldehyde in the gas phase and measuring the amount of C〇2 produced. A Tedlar bag (sampling bag) (manufactured by As〇ne Co., Ltd.) was used as a reaction container. Each of the titanium oxide particles obtained in Examples 1 to 7 and Comparative Examples 1 and 2 was spread on a glass dish, and the titanium oxide particles obtained in the reaction volume of -19-201141609 were placed in a glass. The dish was placed in a reaction vessel, and 500 ppm of acetaldehyde saturated gas was injected into the reaction vessel. After the gas and acetaldehyde are equilibrated, light irradiation is performed at room temperature (). A light source device (product name "SX-UI501XQ", manufactured by Ushio Electric Co., Ltd.) of 500 W is used for the light source, and a light having a wavelength shorter than 350 nm is blocked by using a UV-35 filter. Further, a fine stainless steel sieve was used as a light adjustment filter, and the amount of light was adjusted to 30 mW/cm2. The gas chromatograph (trade name "GC-8A", "GC-14A", manufactured by Shimadzu Corporation) equipped with a hydrogen flame ionization detector equipped with a methanator was used to measure from the start of light irradiation to 150 minutes later. The amount of C〇2 produced (concentration of C〇2 in the reaction vessel). The above photocatalyst activity evaluation results are summarized and shown in the table below. [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative Example 1 Comparative Example 2 Ca concentration (ppm) 520 315 477 338 510 450 542 153 149 From the above results, The rutile-type titanium oxide obtained by the method for producing rutile-type titanium oxide according to the present invention is a rod-shaped rutile-type titanium oxide having a crystal face (00 1 ) (1 1 0 ) (1 1 1 ). It exhibits excellent photocatalytic performance and exhibits excellent oxidation and decomposition of organic compounds. [Possibility of industrial use] When the rod-shaped rutile-type cerium oxide obtained by the method for producing rutile-type titanium oxide of the present invention -20-201141609 is used as a photocatalyst, it is capable of oxidizing organically efficiently. The substance 'is used for the purpose of purifying, deodorizing, purifying water, antibacterial, antifouling, etc. of air. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a crystal obtained by hydrothermal treatment of a trivalent titanium compound and a crystal obtained by hydrothermal treatment of a tetravalent titanium compound under specific conditions. Fig. 2 is a schematic view showing an example of a purification method by a circulating membrane filtration method of rutile-type titanium oxide. Fig. 3 is a schematic view showing an example of a reverse washing method in a purification method by a circulating membrane filtration method of rutile-type titanium oxide. Fig. 4 is a TEM photograph showing the rutile-type titanium oxide obtained in Example 1. Fig. 5 is a TEM photograph showing the rutile-type titanium oxide obtained in Comparative Example 1. [Explanation of main component symbols] (001) Crystallized surface (110) Crystallized surface (111) Crystallized surface -21-