1322131 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種磷酸純化技術’特別係有關於一 種低成本且快速之電子用磷酸之純化方法’以供電子級產 品使用（納、鎮、銘、舒、約與鐵等金屬離子要求在l.Oppm 以下）。 【先前技術】 在電子產品之製造過程中經常需要使用到磷酸，例如 製造液晶面板所需用以形成金屬線路（如鋁線路）之蝕刻液 即混有70%以上的高純化磷酸，但由於電子級規範的磷酸 相當昂貴，故目前的作法為電子級規範的磷酸為佔較大比 例’再混入工業級或食品級的磷酸，以降低成本，但是品 質不好控制。1322131 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a phosphoric acid purification technology 'particularly relates to a low-cost and fast purification method for phosphoric acid for electronic use' for use in electronic grade products (Na, Zhen Metal ions such as Ming, Shu, and iron are required to be below 1.0 ppm. [Prior Art] It is often necessary to use phosphoric acid in the manufacturing process of electronic products, for example, an etching liquid for forming a metal wiring (such as an aluminum wiring) for manufacturing a liquid crystal panel, that is, more than 70% of highly purified phosphoric acid is mixed, but due to electrons The grade specification of phosphoric acid is quite expensive, so the current practice is that the electronic grade specification of phosphoric acid is a large proportion of 'mixed with industrial grade or food grade phosphoric acid to reduce costs, but the quality is not well controlled.
請參閱第1圖，目前電子級規範的磷酸要求鈉（Na)、 鎂（Mg)、鋁（A1)、鉀（K)、鈣（Ca)與鐵（Fe)等金屬離子要求 在1 ·〇 ppm以下，但工業級與食品級的磷酸雖然價格低廉 卻經檢驗得知，無法達到此一要求，其中第1圖的A廠表 示由臺灣某廠提供，B廠表示由中國某廠提供。 一種已知的磷酸純化方法為，將硫化氫與過氧化氫之 氣體通入磷酸中，使重金屬沉澱分離者（如美國專利第 4804526號所揭示者）。另一種磷酸純化方法為，利用有機 溶劑萃取磷酸中之重金屬（如美國專利第4780295號所揭 示者）。然而目前的磷酸純化方法所產生的製造成本過高， 導致電子級磷酸價格昂貴，無法普遍且大量使用。 (5) 5 1322131 【發明内容】 • 本發明之主要目的係在於提供一種電子用磷酸之純 化方法，其主要特徵在於將一工業級或食品級之磷酸溶液 加以稀釋，使其磷酸含量降至5〜20wt%，或是取得在一般 • 磷酸製程中，尚未進行最後濃縮前的5〜20wt。/。磷酸稀釋 . 液，而使磷酸溶液具有良好的去離子作業性，可有效率地 通過離子交換樹脂或/與奈米過濾膜，以除去已稀釋之磷酸 ..籲 溶液内含之早一金屬離子至0.2ppm以下，並在去離子之 後以蒸餾或其他方式脫水，可低成本且大量得到電子用構 酸，以供電子規範所需的用途。 本發明之次一目的係在於提供一種電子用碟酸之純 化方法，其中鱗酸含量降至5〜20 wt%的經稀釋碟酸溶液或 是鱗酸製程中5~20wt%磷酸稀釋液，可以通過離子交換樹 脂、通過一次以上奈米過溏膜（Nanofiltration membrane、 NF membrane)、或是先通過奈米過滤膜再通過離子交換樹 -Φ 脂，以達到高比例除去磷酸溶液内金屬離子之功效，其中 以通過奈米過濾膜及離子交換樹脂之順序為去離子效果 最好且較有量產之實用性。 ·- 依據本發明之一種電子用磷酸之純化方法，首先取得 一待純化之工業级或食品級之磷酸溶液’其含有50〜90 -wt%之碟酸；之後’稀釋上述碟酸溶液’使其碟酸含量降 • 至5〜20wt%或是在一般磷酸的製造過程中’進行最後濃縮 • 前的5~20wt°/〇之磷酸溶液；再藉由離子交換樹脂或/與奈米. 過濾膜以除去已豨釋之磷酸溶液内含之單一金屬離子至 6 1^22131 0.2ppm以下’最後’以蒸餾或其他方式脫除磷酸溶液内含 水伤，即可低成本且大量得到電子用填酸。 【實施方式】 本發明係揭示一種電子用磷酸之純化方法，主要是除 去磷酸内鈉（Na)、鎂（Mg)、鋁（A1)、鉀（κ)、鈣（Ca)與鐵（Fe) 等金屬離子至1.0 ppm以下，達到可低成本製作且可大量 得到之電子用磷酸。請參閱第2圖，該電子用磷酸之純化 方法之流程係主要包含：磷酸取得步驟u、稀釋步驟12、 去離子步驟13以及蒸餾脫水步驟14。並輔以下列幾個實 施例及實驗數據具體說明之。 首先在碟酸取得步驟U中，取得一待純化之工業級 或食品級之磷酸溶液，其含有5〇〜9〇 wt%之磷酸。之後在 稀釋步驟12中，可利用去離子水稀釋上述磷酸溶液，使 其磷酸含量降至5〜20wt%，如此經稀釋之磷酸溶液具有良 好的去離子作業性，可快速通過離子交換樹脂或/與奈米過 濾膜《或是可直接取得在一般磷酸的製造過程中，磷酸稀 釋液尚未進行最後濃縮前其磷酸濃度為5〜2〇wt%。 .之後在去離子步驟13中，則有幾種除去金屬離子的 方式。在第一具體實施例中’取得一種85wt%工業級/食品 級之磷酸溶液’設定於稀釋至含1〇wt%磷酸，再通過離子 父換樹脂以除去其内含之金屬離子，在處理前與處理後均 量測其内含金屬離子的含量《請參閱第3圖，隨著通過離 子交換樹脂之柱床體積（bed volume)填酸溶液量之變化， 其内含納（Na)、鎂（Mg)、鋁（A1)、鉀（K)、鈣（Ca)與鐵（Fe) 7 (S) 1322131 等金屬離子在處理前與處理後有著明顯的移除率，其單— 離子均可降低至0.2ppm以下。而在試驗i與試驗2之移 除率差異係與選用的離子交換樹脂之種類有關。最後，在 步帮14中’以蒸餾或其他方式脫除磷酸溶液内含水份， 使其磷酸含量係上升至8〇wt%以上，即可低成本且大量得 到電子用磷酸（其内含之單一金屬離子約在i 〇ppm左右）。 在第二具體實施例中，取得一種85wt%工業級/食品級 # 之磷酸溶液，設定於稀釋至含l〇wt%磷酸，先通過奈米過 ;慮膜（Nanofiltration membrane，NF membrane)再通過離子 交換樹脂以除去其内含之金屬離子。通常該奈米過遽膜所 倉b之截除分子量（m〇iecuiar weight cutoff，MWCO)係介於 100〜300。在本實施例中，選用的奈米過濾膜係具有耐酸 鹼性’可供作業之酸鹼值係介於〇〜14，可採用k〇Ch公 司（Koch Membrane Systems，Inc.)提供（其截.除分子量為 200)的 SelPO® MPS-34 pH Stable Membrane。接著，通過 ® 離子交換樹脂，.在本實施例中，選用的離子交換樹脂係為 Bayer 公司之 LEWATIT® MonoPlus SP 112，其基質為 styrene-divinylbenzene copolymer(苯乙歸-二乙稀苯共聚 物）。量測已稀釋之磷酸在處理前與處理後之金屬離子含 量，其數值係如第4圖所示，内含之單一金屬離子如納 (Na)、鎂（Mg)、鋁（A1)、鉀（K)、鈣（Ca)與鐵（Fe)等，隨著 通過柱床想積（bed volume)之鱗酸溶液量變化均可降至 ’ 〇.2ppm以下，故相較於第一具體實施例中，除去離子的穩 定性較佳，更可運用於實際量產；最後，在步驟14中以 8 (S) 1322131 蒸餾或其他脫水方式脫除麟酸溶液内含水份’即可有效率 且低成本地得到電子用甚至同電子級之填酸。 在第二具體實施例中’取得一種8 5 wt%食品級之磷酸 /谷液’設疋於稀釋至含2〇wt%、14 wt%與1 〇 wt°/〇碟酸，分 別通過至少一次之奈米過濾膜。請參閱第5圖，在第一次 通過奈米過濾膜以除去金屬離子之後，無論磷酸是稀釋至 20wt%、14 wt%或1〇 wt%，其金屬離子移除率介於 _ 65〜85%，但磷酸濃度太.高則會影響過濾比，使得金屬離子 移除時間加長。其中針對稀釋至1〇wt%之磷酸溶液再通過 第一次奈米過缚膜，其移除率介於75〜9〇%，即是將通過 第一次奈米過濾膜的金屬離子殘留量再移除約8〇%，故可 使鈉（Na)、鎂（Mg)、鋁（A1)、鉀（κ)、鈣（Ca)與鐵（Fe)等金 屬離子的含量下降至〇 2ppm以下。最後，在步驟14中， 以蒸餾或其他方式脫除磷酸溶液内含水份，即可低成本且 I 大量得到電子用磷酸。 本發明之保護範圍當視後附之申請專利範圍所界定 者為準，任何熟知此項技藝者，在不脫離本發明之精神和 範圍内所作之任何變化與修改，均屬於本發明之保護範 圍。 【圖式簡單說明】 第1圖.工業級與食品級之碟酸溶液的金屬離子含量及電 子級規範要求圖表。 第2圓·本發明之電子用碟酸之純化方法之主要流程圖。 第3圖：依據本發明之一第—具體實施例，以通過離子交 9 1322131 換樹脂除去金屬離子之含量表。 第4圖：依據本發明之一第二具體實施例，以通過奈米過 濾膜及離子交換樹脂除去金屬離子之含量表。 第5圖：依據本發明之一第三具體實施例，以通過奈米過 ' 滤膜除去金屬離子之含量表。 【主要元件符號說明】 11 取得工業級或食品級之磷酸溶液 φ 12 稀釋該磷酸溶液 13 除去已稀釋之磷酸溶液内含之金屬離子 蒸餾脫水 14Please refer to Figure 1. Currently, the electronic grade specification of phosphoric acid requires sodium (Na), magnesium (Mg), aluminum (A1), potassium (K), calcium (Ca) and iron (Fe) and other metal ions to be required. Below the ppm, but the industrial grade and food grade phosphoric acid, although low in price, has been tested and found to be unable to meet this requirement. The plant A in Figure 1 is provided by a factory in Taiwan, and the plant B is provided by a factory in China. A known method of purifying phosphoric acid is to pass a gas of hydrogen sulfide and hydrogen peroxide into phosphoric acid to precipitate a heavy metal precipitate (as disclosed in U.S. Patent No. 4,804,526). Another method of purifying phosphoric acid is to extract heavy metals from the phosphoric acid using an organic solvent (as disclosed in U.S. Patent No. 4,780,295). However, the current manufacturing cost of the phosphoric acid purification method is too high, resulting in an expensive electronic grade phosphoric acid which cannot be used universally and in large quantities. (5) 5 1322131 SUMMARY OF THE INVENTION The main object of the present invention is to provide a method for purifying phosphoric acid for electronic use, which is characterized in that an industrial grade or food grade phosphoric acid solution is diluted to reduce the phosphoric acid content to 5 ~20wt%, or 5~20wt before the final concentration in the general • phosphoric acid process. /. Phosphoric acid dilution, liquid, and the phosphoric acid solution has good deionization work, can be efficiently passed through the ion exchange resin or / and the nanofiltration membrane to remove the diluted phosphoric acid. It is less than 0.2 ppm, and is dehydrated by distillation or other means after deionization, and the acid structuring for electrons can be obtained at low cost and in large quantities for the purpose required for electronic specifications. A second object of the present invention is to provide a method for purifying a dish acid for electrons, wherein the bismuth acid content is reduced to 5 to 20 wt% of the diluted dish acid solution or the 5-20 wt% phosphoric acid dilution solution in the bismuth process. The effect of removing metal ions in the phosphoric acid solution by ion exchange resin, through one or more nanofiltration membranes (NF membrane), or through the nanofiltration membrane and then through the ion exchange tree-Φ lipid. Among them, the order of passing through the nanofiltration membrane and the ion exchange resin is the best and the mass production is practical. According to the method for purifying phosphoric acid for electronic use according to the present invention, first, a technical grade or food grade phosphoric acid solution to be purified, which contains 50 to 90% by weight of a disc acid, and then 'diluted the above-mentioned dish acid solution' is obtained. The acid content of the dish is reduced to 5~20wt% or in the general phosphoric acid production process, the final concentration of 5~20wt ° / 磷酸 phosphoric acid solution is carried out; and then filtered by ion exchange resin or / and nano. The membrane removes the single metal ion contained in the released phosphoric acid solution to 6 1^22131 0.2 ppm or less 'final' by distillation or other means to remove the water-containing damage in the phosphoric acid solution, so that the electron can be filled at a low cost and in a large amount. acid. [Embodiment] The present invention discloses a method for purifying phosphoric acid for electrons, mainly for removing sodium phosphate (Na), magnesium (Mg), aluminum (A1), potassium (κ), calcium (Ca) and iron (Fe). When the metal ion is less than 1.0 ppm, phosphoric acid for electrons which can be produced at a low cost and which can be obtained in a large amount is obtained. Referring to Fig. 2, the process for purifying the phosphoric acid for electronic use mainly comprises a phosphoric acid obtaining step u, a diluting step 12, a deionizing step 13 and a distillation dehydrating step 14. It is described in detail with the following examples and experimental data. First, in the dish acid obtaining step U, an industrial grade or food grade phosphoric acid solution to be purified containing 5 Torr to 9 Å wt% phosphoric acid is obtained. Then in the dilution step 12, the phosphoric acid solution can be diluted with deionized water to reduce the phosphoric acid content to 5 to 20 wt%, and the diluted phosphoric acid solution has good deionization workability and can be quickly passed through the ion exchange resin or With the nanofiltration membrane "or directly in the manufacturing process of the general phosphoric acid, the phosphoric acid dilution has not been subjected to final concentration before the final concentration of the phosphoric acid is 5 to 2% by weight. Then in the deionization step 13, there are several ways to remove the metal ions. In the first embodiment, 'obtaining an 85 wt% industrial grade/food grade phosphoric acid solution' is set to be diluted to 1 wt% phosphoric acid, and then the resin is replaced by an ion parent to remove the metal ions contained therein, before treatment. The content of the contained metal ions is measured after the treatment. Please refer to Fig. 3, which contains sodium (Na) and magnesium as the amount of the acid solution in the bed volume of the ion exchange resin changes. Metal ions such as (Mg), aluminum (A1), potassium (K), calcium (Ca) and iron (Fe) 7 (S) 1322131 have obvious removal rates before and after treatment, and single ions can be used. Reduced to below 0.2ppm. The difference in the removal rates between test i and test 2 is related to the type of ion exchange resin selected. Finally, in the step 14, the water content in the phosphoric acid solution is removed by distillation or other means, and the phosphoric acid content is increased to 8 〇wt% or more, so that the phosphoric acid for electrons can be obtained at a low cost and in a large amount. A single metal ion is about i 〇ppm). In a second embodiment, a 85 wt% industrial grade/food grade # phosphoric acid solution is obtained, which is set to be diluted to contain 1% by weight of phosphoric acid, first passed through the nanometer; and the membrane (Nanofiltration membrane, NF membrane) is passed again. The ion exchange resin is used to remove metal ions contained therein. Usually, the m〇iecuiar weight cutoff (MWCO) of the nanometer membrane is between 100 and 300. In this embodiment, the selected nanofiltration membrane has acid and alkali resistance, and the available pH value is between 〇~14, which can be supplied by Koch Membrane Systems, Inc. Cut off SelPO® MPS-34 pH Stable Membrane with a molecular weight of 200). Next, through the ion exchange resin, in this embodiment, the ion exchange resin selected is Bayer's LEWATIT® MonoPlus SP 112, and the substrate is styrene-divinylbenzene copolymer. . Measure the metal ion content of the diluted phosphoric acid before and after treatment. The values are as shown in Figure 4, and the single metal ions such as nano (Na), magnesium (Mg), aluminum (A1), and potassium are contained. (K), calcium (Ca) and iron (Fe), etc., as the amount of scaly acid solution that passes through the bed bed can be reduced to less than 2 ppm, so compared with the first implementation In the example, the stability of the removed ions is better, and it can be applied to actual mass production. Finally, in step 14, the water content in the linonic acid solution can be removed by 8 (S) 1322131 distillation or other dehydration method. And the electrons are used at low cost, even with the same level of acid filling. In the second embodiment, 'obtaining a 185 wt% food grade phosphoric acid/trough liquor' is set to dilute to 2 〇 wt%, 14 wt% and 1 〇 wt ° / 〇 酸 acid, respectively, at least once Nano filter membrane. Referring to Figure 5, after the first pass of the nanofiltration membrane to remove metal ions, the metal ion removal rate is between _ 65 and 85, regardless of whether the phosphoric acid is diluted to 20 wt%, 14 wt% or 1 wt%. %, but the phosphoric acid concentration is too high, which will affect the filtration ratio, making the metal ion removal time longer. The phosphoric acid solution diluted to 1% by weight is passed through the first nano-passing membrane, and the removal rate is between 75 and 9%, which is the residual amount of metal ions that will pass through the first nanofiltration membrane. After removing about 8〇%, the content of metal ions such as sodium (Na), magnesium (Mg), aluminum (A1), potassium (κ), calcium (Ca) and iron (Fe) can be reduced to below ppm2ppm. . Finally, in step 14, the water content in the phosphoric acid solution is removed by distillation or other means, and the phosphoric acid for electrons can be obtained in a large amount at a low cost. The scope of the present invention is defined by the scope of the appended claims, and any changes and modifications made by those skilled in the art without departing from the spirit and scope of the invention are within the scope of the present invention. . [Simple diagram of the diagram] Figure 1. Chart of metal ion content and electronic grade specifications for industrial grade and food grade dish acid solutions. Second Circle The main flow chart of the purification method of the dish acid for electronic use of the present invention. Fig. 3 is a table showing the content of metal ions removed by ion exchange 9 1322131 in accordance with one embodiment of the present invention. Fig. 4 is a view showing the content of metal ions removed by a nanofiltration membrane and an ion exchange resin according to a second embodiment of the present invention. Fig. 5 is a table showing the removal of metal ions by a nanofiltration membrane according to a third embodiment of the present invention. [Main component symbol description] 11 Obtain industrial grade or food grade phosphoric acid solution φ 12 Dilute the phosphoric acid solution 13 Remove the metal ions contained in the diluted phosphoric acid solution Distillation and dehydration 14