200532030 玖、發明說明： (一） 發明所屬之技術領域 本發明關於從內燃機之排氣淨化用等中使用過的金屬 載體觸媒裝置之金屬載體分離回收載有含貴金屬觸媒成分 之洗塗層（washcoat)，以及關於貴金屬的回收方法。 (二） 先前技術 作用內燃機之排氣淨化用觸媒裝置的觸媒載體，有陶 瓷載體或金屬載體。 作爲由陶瓷載體觸媒裝置回收貴金屬方法，一般有藉 由鹽酸、王水等的酸溶解。然而，採用該酸溶解法於金屬 載體觸媒裝置時，需要大量的酸來溶解金屬載體，而且有 難以有效地由溶解液分離出貴金屬的問題。 因此，作爲由金屬載體觸媒裝置回收貴金屬之方法， 以往有各種提案。 例如，特開平8-26 69 1 1號公報中揭示藉由使用載有貴 金屬的金屬製蜂巢體所成的金屬載體被氧過剩火炎所燒 烤，以該蜂巢體當作燃燒過的氧化物粒子而落下粉碎後， 例如藉由磁選以去除氧化物而回收貴金屬之方法。又，特 開平Π - 1 5 8 5 6 3號公報中揭示藉由將金屬載體觸媒轉化器 的金屬載體加熱至高溫，接著以冷水來急速冷卻該金屬載 體以由該金屬載體剝離含貴金屬的洗塗層，而從金屬載體 觸媒轉化器回收貴金屬之方法。 再者’特開平8-34619號公報中揭示於金屬載體基材上 形成耐火性無機氧化物且該無機氧化物層中含有貴金屬的 200532030 金屬載體觸媒，藉由將其浸入30容量％以上的硫酸及/或 磷酸的溶液中及加熱以使金屬載體觸媒的觸媒層溶解’而 使金屬載體觸媒與金屬載體基和觸媒層分離’以從溶解 '液 和觸媒層之未溶解殘渣中回收貴金屬之方法。然後’在該 方法中，當酸溶液消耗在觸媒層的溶解時’反應係平穩地 進行，但是當觸媒層變少時，由於金屬載體基材係急劇溶 解，故難以對觸媒層作選擇地分離。 (三）發明內容 本發明之主要目的爲提供從使用過的金屬載體觸媒裝 置之金屬載體有效率地分離回收載有含貴金屬觸媒成分的 洗塗層之方法，該金屬載體係用於內燃機的排氣之淨化等。 在該方法中，該金屬載體實質上不會破碎或溶解。 本發明另一目的爲提供由所分離回收的載有含貴金屬 觸媒成分的洗塗層回收貴金屬之方法。 本發明又一目的爲提供由所分離回收的載有含貴金屬 觸媒成分的洗塗層回收貴金屬之方法。 由以下說明可明瞭本發明之其它目的和特徵。 本案發明人爲了達成上述目的而專心致力地重複檢 討’結果發現若以含硫酸和硝酸的混合酸水溶液來處理使 用過的金屬載體觸媒裝置時，則金屬載體實質上不會溶解， 且可容易地從金屬載體分離回收載有含貴金屬觸媒成分的 洗塗層，而終於完成本發明。 因此’本發明提供一種從金屬載體觸媒裝置分離回收 載有觸媒成分的洗塗層之方法，其特徵爲以含有硫酸和硝 200532030 酸的混合酸水溶液來處理一由設有洗塗層的金屬載體與該 洗塗層所承載的含貴金屬觸媒成分所構成的金屬載體觸媒 裝置。 本發明提供一種從金屬載體觸媒裝置回收貴金屬之方 法’其特徵爲從上述方法所分離回收的載有觸媒成分的洗 塗層及所回收的混合酸水溶液中，藉由本身已知的方法來 回收貴金屬。 (四）實施方式 以下更詳細說明本發明。 作爲依照本發明的方法所可處理的金屬載體觸媒裝 置，例如爲於耐熱性不鋼或鐵-鉻-鋁合金等耐熱性金屬的 箔所形成的蜂巢構造體等的金屬載體的表面上，形成活性 氧化鋁、鉻等的耐火性無機氧化物之多孔質層，即洗塗層， 於該層上載有鉑、铑、鈀等的貴金屬所成的觸媒成分者， 或是將載有觸媒成分的金屬載體收納於耐熱性金屬製外筒 內者等。它們大多使用於淨化汽車或鍋爐等的各種內燃機 之排氣，於汽車等時係於廢車手續後廢棄，而且於鍋爐等 時係於觸媒能力降低時作更換。 本發明係以含有硫酸和硝酸的混合酸水溶液來處理該 使用過的金屬載體觸媒裝置。於該混合酸水溶液中，硫酸 係主要溶解洗塗層中所含有的氧化鋁等金屬氧化物’以有 助於洗塗層的脆化，另一方面，硝酸係使得在金屬載體表 面上形成氧化被膜，而抑制金屬載體被硫酸溶解，即有助 於保護金屬載體防止溶解。 200532030 然而，在本發明所用的混合酸水溶液中，硫酸和硝酸 的濃度並沒有嚴格限制，而可視處理對象的金屬載體觸媒 裝置之材質或形狀等來改變，但通常硫酸爲5〜50重量％， 較佳7.5〜40重量％，更佳1〇〜30重量％的濃度，而且硝酸 爲0· 1〜5重量％，較佳0·5〜4重量％，更佳1〜3重量％的濃 度。 上述混合酸水溶液中視情況可含有任意成分，例如少 量的磷酸、醋酸、草酸、檸檬酸及此等之鹽等，較佳爲在 1〜5重量％的濃度範圔內。 上述混合酸水溶液對於金屬載體觸媒裝置的處理，例 如可藉由將使用過的金屬載體觸媒裝置浸入混合酸水溶液 中以進行。在此情況下，該混合酸水溶液的溫度係沒有特 別的限制，但通常可爲常溫至約1 50 °C的範圍內的溫度。 然而，在低溫時洗塗層的溶解係費時，故通常在約60〜約 1 〇〇°c溫度處理係較宜的。又，處理時間亦沒有特別的限制， 但較佳爲於硝酸被消耗而在金屬載體表面上不形成新的氧 化被膜之前結束反應，再者，該混合酸水溶液的處理，視 需要可重複數次來進行。 因此，金屬載體觸媒裝置的金屬載體上之載有含貴金 屬觸媒成分的洗塗層之相當大的部分係溶解在混合酸中， 視處理條件而定，洗塗層的一部可以未溶解狀態由金屬載 體剝離，可以未溶解的狀態於混合酸中分離回收。另一方 面，金屬載體係實質上不溶解，而可由混合酸水溶液中取 出0 200532030 含有溶解狀態的如上述所分離回收的載貴金屬成分的 洗塗層且視丨、胃況含有未溶解殘渣的混合酸水溶液，接著按 照需要’藉由一般的固-液分離手段，將溶解含有載觸媒成 分的洗塗層與未溶解的殘渣作分離後，可依照本身已知的 貴金屬回收，例如「高純度技術大系」第3冊的高純物質 製造方法第IV篇第5 73〜5 76頁（1 997年12月12日，弗西 科技統股份有限公司發行，橫濱國立大學工學部物質工學 科教授大矢晴彥監修）中所記載的方法，由其分別回收貴 金屬。 具體地，例如由溶解含有載觸媒成分的洗塗層之混合 酸水溶液，使用氫或鐵粉等的還原性物質對其作還原處理， 而可析出貴金屬。所析出的貴金屬視需要可溶解於王水中 而進一步精製。另外，未溶解的殘渣在溶解於王水後，可 藉由一般的方法（例如沈澱分離法）從該溶液回收貴金屬。 依照上述本發明的方法，以含有硫酸和硝酸的混合酸 水溶液來處理金屬載體觸媒裝置，硫酸係具有溶解金屬載 體上的載觸媒成分之洗塗層的作用，而硝酸係具有在金屬 載體表面上形成氧化被膜的作用以保護金屬載體表面避免 被硫酸所溶解，結果不會實質溶解金屬載體，而有效地從 金屬載體分離載觸媒成分的洗塗層。 實施例 以下藉由實施例來更具體說明的方法，但是應了解的 是本發明之範圍不受該些實施例所限制。 參考例1 -9- 200532030 以140克活性氧化鋁來塗覆直徑900nlm、高度126〇mm 的耐熱不銹鋼蜂巢體（以下稱爲金屬載體，容量80Occ)，烘 烤後’使每個金屬載體承載〇.3克鉑（Pt)、2.3克鈀（Pd)及 0.3克鍺（Rh)，以製作金屬載體觸媒裝置。 實施例1 依照第1圖所示的流程圖，將參考例1所製作的金屬 載體觸媒裝置浸入含20重量％硫酸及2重量％硝酸的水溶 液中，於8 0 °C處理5小時。放置冷卻後，由上述水溶液取 出金屬載體（1)，將該金屬載體水洗，使洗液和該水溶液成 一起，而得到含有未溶解殘渣的水溶液（2)。所回收的金屬 載體係與上述活性氧化鋁塗覆前的金屬載體之外觀相同， 沒有看到任何溶解的形跡。 將水溶液（2)過濾，使未溶解殘渣（3)與水溶液（4)分離 後，將10克鐵（Fe)粉加到水溶液（4)以作還成處理，析出 貴金屬（Pt、Pd、Rh)成分（5)，將其回收。接著，將所回收 的貴金屬成分（5)和未溶解殘渣（3)投入王水中使溶解，而 得到溶液化的貴金屬成分（6)。依照ICP(感應耦合氬電漿） 發光分析法來分析金屬載體（1)上所殘留的貴金屬成分及溶 液化貴金屬成分（6)，以對Pt、Pd及Rh作定量。結果示於 表1中。 實施例2 依照第1圖所示的流程圖，將參考例1所製作的金屬 載體觸媒裝置浸入含20重量％硫酸及2重量％硝酸的水溶 液中，於80°C處理5小時，由上述水溶液取出金屬載體（1)， 200532030 浸入新調製的含20重量％硫酸及2重量％硝酸的水溶液中， 再於80°C處理5小時。放置冷卻後，將該金屬載體水洗， 使洗液和該水溶液成一起，而得到含有未溶解殘渣的水溶 液（2)。所回收的金屬載體係與上述活性氧化鋁塗覆前的金 屬載體之外觀相同，沒有看到任何溶解的形跡。 將水溶液（2)過濾，使未溶解殘渣（3)與水溶液（4)分離 後，將10克鐵（Fe)粉加到水溶液（4)以作還成處理，析出 貴金屬（Pt、Pd、Rh)成分（5)，將其回收。接著，將所回收 的貴金屬成分（5)和未溶解殘渣（3)投入王水中使溶解，而 得到溶液化的貴金屬成分（6)。金屬載體（1)上所殘留的貴 金屬成分及溶液化貴金屬成分（6)分別經與實施例1同樣的 分析，以對Pt、Pd及Rh作定量。結果示於表1中。 比較例1 使用含20重量％硫酸的水溶液來代替含20重量％硫酸 及2重量％硝酸的水溶液，且使用新調製的該水溶液來作 浸漬處理重複3次，以外係與實施例1同樣地操作。結果 示於表1中。再者，確認經浸漬處理的金屬載體（1)係一部 分溶解。 比較例2 使用含3 0重量％硫酸及5重量％磷酸的水溶液來代替 含20重量％硫酸及2重量％硝酸的水溶液，且使用新調製 的該水溶液來作浸漬處理重複3次，以外係與實施例1同 樣地操作。結果示於表1中。再者’確認經浸漬處理的金 屬載體（1)係一部分溶解。 200532030 比較例3 使用含3 0重量％磷酸的水溶液來代替含20重量％硫酸 及2重量％硝酸的水溶液，且使用新調製的該水溶液來作 浸漬處理重複3次，以外係與實施例1同樣地操作。結果 示於表1中。再者，確認經浸漬處理的金屬載體（1)係一部 分溶解。 表1200532030 (1) Description of the invention: (1) The technical field to which the invention belongs The present invention relates to the separation and recovery of a wash coat containing a precious metal catalyst component from a metal carrier of a metal carrier catalyst device used in exhaust purification of internal combustion engines and the like. (Washcoat), and methods for recycling precious metals. (2) Prior technology The catalyst carrier used in the catalyst purification device for exhaust gas purification of internal combustion engines includes ceramic carrier or metal carrier. As a method for recovering a precious metal from a ceramic carrier catalyst device, there is generally a method of dissolving the precious metal with an acid such as hydrochloric acid and aqua regia. However, when this acid dissolving method is used in a metal carrier catalyst device, a large amount of acid is required to dissolve the metal carrier, and there is a problem that it is difficult to effectively separate the precious metal from the dissolving solution. Therefore, various methods have been proposed as methods for recovering precious metals from metal-supported catalyst devices. For example, Japanese Patent Application Laid-Open No. 8-26 69 1 discloses that a metal carrier formed by using a metal honeycomb body carrying precious metals is grilled by an excess oxygen flame, and the honeycomb body is used as burned oxide particles. After dropping and crushing, for example, a method of recovering precious metals by magnetic separation to remove oxides. Furthermore, Japanese Patent Application Laid-Open No. Π-1 5 8 5 6 3 discloses that a metal carrier of a metal carrier catalyst converter is heated to a high temperature, and then the metal carrier is rapidly cooled with cold water to peel off the precious metal-containing metal carrier from the metal carrier. Method for washing coating and recovering precious metal from metal carrier catalyst converter. Furthermore, Japanese Patent Application Laid-Open No. 8-34619 discloses a 200532030 metal carrier catalyst in which a refractory inorganic oxide is formed on a metal carrier substrate and a precious metal is contained in the inorganic oxide layer. The solution of sulfuric acid and / or phosphoric acid is neutralized and heated to dissolve the catalyst layer of the metal carrier catalyst, and to separate the metal carrier catalyst from the metal carrier base and the catalyst layer to dissolve the solution and the undissolved catalyst layer. Method for recovering precious metals from residues. Then, in this method, when the acid solution is consumed in the dissolution of the catalyst layer, the reaction proceeds smoothly, but when the catalyst layer becomes smaller, the metal carrier substrate system is rapidly dissolved, so it is difficult to make the catalyst layer. Selectively separate. (3) Summary of the invention The main object of the present invention is to provide a method for efficiently separating and recovering a washcoat containing precious metal catalyst components from a metal carrier of a used metal carrier catalyst device. The metal carrier is used in an internal combustion engine. Purification of exhaust gas. In this method, the metal support is not substantially broken or dissolved. Another object of the present invention is to provide a method for recovering a precious metal from a separated and recovered wash coat carrying a precious metal-containing catalyst component. Still another object of the present invention is to provide a method for recovering precious metals from a separated and recovered wash coat carrying a precious metal-containing catalyst component. Other objects and features of the present invention will be apparent from the following description. In order to achieve the above purpose, the inventor of the present case intensively repeated the review. As a result, it was found that when the used metal carrier catalyst device is treated with a mixed acid aqueous solution containing sulfuric acid and nitric acid, the metal carrier will not substantially dissolve and can be easily dissolved. The washcoat containing the precious metal catalyst component was separated and recovered from the metal carrier, and finally the present invention was completed. Therefore, the present invention provides a method for separating and recovering a catalyst-containing wash coating from a metal-supported catalyst device, which is characterized in that a mixed acid aqueous solution containing sulfuric acid and nitric acid 200532030 is used to treat A metal carrier catalyst device composed of a metal carrier and a precious metal-containing catalyst component carried by the wash coat. The present invention provides a method for recovering precious metals from a metal carrier catalyst device, which is characterized in that the catalyst component-containing washcoat layer and the recovered mixed acid aqueous solution separated and recovered from the above method are processed by a method known per se To recycle precious metals. (IV) Embodiments The present invention will be described in more detail below. As the metal carrier catalyst device that can be processed by the method according to the present invention, for example, on the surface of a metal carrier such as a honeycomb structure formed of a heat resistant metal or a foil of a heat resistant metal such as iron-chromium-aluminum alloy, Forms a porous layer of refractory inorganic oxides such as activated alumina and chromium, that is, a washcoat layer, on which a catalyst component made of precious metals such as platinum, rhodium, and palladium is carried, or The metal carrier of the medium component is housed in a heat-resistant metal outer cylinder or the like. Most of them are used to purify the exhaust gas of various internal combustion engines such as automobiles and boilers. They are discarded after the waste car procedure in the case of automobiles, etc., and they are replaced when the catalyst capacity is reduced in the case of boilers and the like. In the present invention, the used metal carrier catalyst device is treated with a mixed acid aqueous solution containing sulfuric acid and nitric acid. In this mixed acid aqueous solution, the sulfuric acid system mainly dissolves metal oxides such as alumina contained in the washcoat layer to facilitate embrittlement of the washcoat layer. On the other hand, the nitric acid system causes oxidation to form on the surface of the metal support. Coating, and inhibiting the metal carrier from being dissolved by sulfuric acid, that is, helping to protect the metal carrier from dissolution. 200532030 However, in the mixed acid aqueous solution used in the present invention, the concentrations of sulfuric acid and nitric acid are not strictly limited, and can be changed depending on the material or shape of the metal carrier catalyst device to be processed, but usually the sulfuric acid is 5 to 50% by weight It is preferably 7.5 to 40% by weight, more preferably 10 to 30% by weight, and nitric acid is 0.1 to 5% by weight, preferably 0.5 to 4% by weight, and more preferably 1 to 3% by weight. . The above-mentioned mixed acid aqueous solution may contain optional components as appropriate, such as a small amount of phosphoric acid, acetic acid, oxalic acid, citric acid, and the like, and it is preferably within a concentration range of 1 to 5% by weight. The treatment of the metal carrier catalyst device by the above mixed acid aqueous solution can be performed, for example, by immersing the used metal carrier catalyst device in the mixed acid aqueous solution. In this case, the temperature of the mixed acid aqueous solution is not particularly limited, but it can usually be a temperature in the range of ordinary temperature to about 150 ° C. However, the dissolution of the washcoat at a low temperature is time-consuming, so it is usually preferable to treat it at a temperature of about 60 to about 1000 ° C. The treatment time is not particularly limited, but it is preferable to terminate the reaction before the nitric acid is consumed and no new oxide film is formed on the surface of the metal support. Furthermore, the treatment of the mixed acid aqueous solution may be repeated several times as necessary. Come on. Therefore, a considerable part of the wash coating containing the precious metal catalyst component on the metal support of the metal carrier catalyst device is dissolved in the mixed acid. Depending on the processing conditions, a part of the wash coating may not be dissolved. The state is separated from the metal carrier, and can be separated and recovered in the mixed acid in an undissolved state. On the other hand, the metal carrier is substantially insoluble, but can be taken out from the mixed acid aqueous solution. 200532030 A mixed coating containing a noble metal component separated and recovered as described above in a dissolved state and containing undissolved residues depending on the stomach condition The acid aqueous solution is then used to separate the wash coat containing the catalyst-containing component from the undissolved residue by ordinary solid-liquid separation methods, and then can be recovered in accordance with known precious metals such as "high purity "Department of Technology" Volume 3, High-Purity Substances Manufacturing Methods, Section IV Pages 5 73 ~ 5 76 (issued on December 12, 1997 by Forsyth Technology Co., Ltd., Professor of Physical Engineering, Faculty of Engineering, Yokohama National University Supervised by Oya Haruhiko) to recover precious metals separately. Specifically, for example, a noble metal can be precipitated from a mixed acid aqueous solution in which a wash coat layer containing a catalyst component is dissolved, and a reducing substance such as hydrogen or iron powder is used for the reduction treatment. The precipitated precious metal can be dissolved in aqua regia and further refined if necessary. In addition, after the undissolved residue is dissolved in aqua regia, the precious metal can be recovered from the solution by a general method (such as a precipitation separation method). According to the method of the present invention, the metal carrier catalyst device is treated with a mixed acid aqueous solution containing sulfuric acid and nitric acid. The sulfuric acid system has the function of dissolving the catalyst-carrying coating on the metal carrier, and the nitric acid system has the function of An oxide film is formed on the surface to protect the surface of the metal carrier from being dissolved by sulfuric acid. As a result, the metal carrier is not substantially dissolved, and the catalyst-containing wash coat is effectively separated from the metal carrier. Examples The method will be described in more detail with examples below, but it should be understood that the scope of the present invention is not limited by these examples. Reference Example 1 -9- 200532030 Coated with 140 g of activated alumina, a heat-resistant stainless steel honeycomb body with a diameter of 900 nlm and a height of 1260 mm (hereinafter referred to as a metal carrier with a capacity of 80 Occ), after baking, 'each metal carrier was carried. .3 grams of platinum (Pt), 2.3 grams of palladium (Pd) and 0.3 grams of germanium (Rh) to make a metal carrier catalyst device. Example 1 According to the flowchart shown in Fig. 1, the metal-supported catalyst device produced in Reference Example 1 was immersed in an aqueous solution containing 20% by weight sulfuric acid and 2% by weight nitric acid, and treated at 80 ° C for 5 hours. After leaving to cool, the metal carrier (1) was taken out from the aqueous solution, and the metal carrier was washed with water, and the washing solution and the aqueous solution were combined to obtain an aqueous solution (2) containing undissolved residues. The recovered metal carrier had the same appearance as the metal carrier before the above-mentioned activated alumina coating, and no traces of dissolution were seen. The aqueous solution (2) was filtered to separate the undissolved residue (3) from the aqueous solution (4), and 10 g of iron (Fe) powder was added to the aqueous solution (4) to perform a reduction treatment to precipitate precious metals (Pt, Pd, Rh). ) Component (5) and collect it. Next, the recovered precious metal component (5) and the undissolved residue (3) were put into aqua regia and dissolved to obtain a solubilized precious metal component (6). The ICP (inductively coupled argon plasma) luminescence analysis method was used to analyze the noble metal components and the liquefied noble metal components (6) remaining on the metal support (1) to quantify Pt, Pd, and Rh. The results are shown in Table 1. Example 2 According to the flowchart shown in FIG. 1, the metal carrier catalyst device prepared in Reference Example 1 was immersed in an aqueous solution containing 20% by weight sulfuric acid and 2% by weight nitric acid, and treated at 80 ° C for 5 hours. The metal support (1) was taken out from the aqueous solution, and 200532030 was immersed in a freshly prepared aqueous solution containing 20% by weight sulfuric acid and 2% by weight nitric acid, and then treated at 80 ° C for 5 hours. After leaving to cool, the metal carrier was washed with water, and the washing solution and the aqueous solution were brought together to obtain an aqueous solution (2) containing undissolved residues. The recovered metal carrier had the same appearance as the metal carrier before the above-mentioned activated alumina coating, and no traces of dissolution were seen. The aqueous solution (2) was filtered to separate the undissolved residue (3) from the aqueous solution (4), and 10 g of iron (Fe) powder was added to the aqueous solution (4) to perform a reduction treatment to precipitate precious metals (Pt, Pd, Rh). ) Component (5) and collect it. Next, the recovered precious metal component (5) and the undissolved residue (3) were put into aqua regia and dissolved to obtain a solubilized precious metal component (6). The noble metal component and the solubilized noble metal component (6) remaining on the metal carrier (1) were analyzed in the same manner as in Example 1 to quantify Pt, Pd, and Rh. The results are shown in Table 1. Comparative Example 1 An aqueous solution containing 20% by weight sulfuric acid was used instead of an aqueous solution containing 20% by weight sulfuric acid and 2% by weight nitric acid, and the freshly prepared aqueous solution was used for immersion treatment and repeated 3 times. . The results are shown in Table 1. Furthermore, it was confirmed that the metal carrier (1) subjected to the immersion treatment was partially dissolved. Comparative Example 2 An aqueous solution containing 30% by weight sulfuric acid and 5% by weight phosphoric acid was used instead of an aqueous solution containing 20% by weight sulfuric acid and 2% by weight nitric acid, and the newly prepared aqueous solution was used for immersion treatment and repeated 3 times. Example 1 was performed in the same manner. The results are shown in Table 1. Further, it was confirmed that a part of the metal carrier (1) subjected to the immersion treatment was dissolved. 200532030 Comparative Example 3 An aqueous solution containing 30% by weight of phosphoric acid was used instead of an aqueous solution containing 20% by weight of sulfuric acid and 2% by weight of nitric acid, and the freshly prepared aqueous solution was used for immersion treatment three times.地 OPERATION. The results are shown in Table 1. Furthermore, it was confirmed that the metal carrier (1) subjected to the immersion treatment was partially dissolved. Table 1
Pt Pd Rh 實施例1 金屬載體（1)上所殘留的貴金屬成分(克） 0.02 0.30 0.06 溶液化的貴金屬成分(6)(克） 0.27 1.99 0.23 貴金屬成分回收率(^^)※ 93.1 86.8 79.3 實施例2 金屬載體（1)上所殘留的貴金屬成分(克） 0.00 0.00 0.00 溶液化的貴金屬成分(6)(克） 0.31 2.33 0.31 貴金屬成分回收率(％)《 99.9 99.9 99.9 比較例1 金屬載體（1)上所殘留的貴金屬成分(克） 0.08 0.61 0.16 溶液化的貴金屬成分(6)(克） 0.21 1.74 0.17 貴金屬成分回收率作)※ 72.4 74.0 51.5 比較例2 金屬載體（1)上所殘留的貴金屬成分(克） 0.13 1.00 0.15 溶液化的貴金屬成分(6)(克） 0.16 1.32 0.14 貴金屬成分回收率(％)《 55.2 56.9 48.3 比較例3 金屬載體（1)上所殘留的貴金屬成分(克） 0.24 1.90 0.27 溶液化的貴金屬成分(6)(克） 0.06 0.43 0.05 貴金屬成分回收率^义)※ 20.0 18.5 15.6 ※貴金屬成分溶液化率（％)= _溶液化的貴金屬成分(克)_x]00 金屬載體上所殘留的貴金屬成分(克)+溶液化的貴金屬成分(克） (五）圖式簡單說明 第1圖係實施例1和2所用的方法之示意流程圖。Pt Pd Rh Example 1 Precious metal component (g) remaining on metal carrier (1) 0.02 0.30 0.06 Precipitated metal component (6) (g) 0.27 1.99 0.23 Recovery rate of precious metal component (^^) ※ 93.1 86.8 79.3 Implementation Example 2 Precious metal component (g) remaining on metal carrier (1) 0.00 0.00 0.00 Precipitated metal component (6) (g) 0.31 2.33 0.31 Recovery rate of precious metal component (%) "99.9 99.9 99.9 Comparative Example 1 Metal carrier ( 1) Precious metal component (g) 0.08 0.61 0.16 Precipitated metal component (6) (g) 0.21 1.74 0.17 Recovery rate of precious metal component * 72.4 74.0 51.5 Comparative Example 2 Remaining metal substrate (1) Precious metal component (g) 0.13 1.00 0.15 Solution precious metal component (6) (g) 0.16 1.32 0.14 Precious metal component recovery (%) "55.2 56.9 48.3 Comparative Example 3 Precious metal component (g) remaining on metal carrier (1) 0.24 1.90 0.27 Soluble precious metal component (6) (g) 0.06 0.43 0.05 Precious metal component recovery rate (meaning) ※ 20.0 18.5 15.6 ※ Precious metal component solution rate (%) = _Soluted precious metal component ( (G) _x] 00 Remaining precious metal component (g) + solubilized precious metal component (g) on the metal support (e) Brief description of the diagram Figure 1 is a schematic flowchart of the method used in Examples 1 and 2.