200926497 九、發明說明： 【發明所屬之技術領域】 本發明係關於-觀騎合成方法，尤指㈣電池重組器觸 媒的合成方法。 【先前技術】 Ο 近年來由於環境保護意識的抬頭，加上能源銳減、石油曰益 栝竭的危機，迫使人們不得不重視能源危機的問題，使得非石化 能源的燃料電池(Fuel ceii)越來越受到重視。過去幾十年，國際 上燃料電池技術突破性發展，燃料電池除了具高效率、原料易取 得及污染性低等優勢之外，另外在廢棄物方面，也僅產生熱和水， 可大量減少空氣受到汙染的影響，這使得燃料電池被認為最具有 潛力之能源方式。正因為如此，燃料電池已逐漸取代傳統發電機 ❹及内燃機’而被廣泛運用於發電及交通工具上。 燃料電池依電解質不同而有不同的種類，分磷酸型（PAFC， Phosphate Fuel Cell )、溶融碳酸鹽型（MCFC，Melt Carbonate Fuel Cell )、固態氧化物型（SOFC，Solid Oxide Fuel Cell )、 與質子交換膜型（PEMFC，Proton Exchange Membrane Fuel Cel 1 ) 等。 目前以PEMFC所謂高分子電解質燃料電池（、PEMFC )研究最 深’是指其電解質是使用高分子薄膜所組成的燃料電池，高分子 200926497 薄膜為一種絕緣體，具有傳導氫離子功能，可隔絕陰極和陽極的 反應氣體’氣體通常為氫氣和氧氣。發展至今，在1〇千瓦以下的 燃料電池以質子交換膜燃料電池（PEMFC)的技術最為成熟。 燃料電池中必備之要素為氧氣及氫氣。氧氣可直接取至大 乾’而氫氣可利用太陽能、水力發電方式電解產生氫氣，但是由 於受到環境及技娜礙，魏紐突破。再加上卿電解反應產 生氫氣不易儲存，且在運送上可能發生不穩定或是***的可能 ❹性，因此目前傾向利用燃料製程器（fuel pr〇cess〇r)中的重組器 (reformer)將碳氫化合物(如甲⑨、甲醇、天燃氣、輕油等富氯化 α物)經燃燒反應方式取得絲，可藉此避免氮氣在儲存、填充和 運送^安全性等_考#，只需填充碳氫化合物柿於重組器來 製造氫氣，隨後氫氣再提供給燃料電池即可，一氣口可成。 石反風化合物之中，以甲醇的燃料品質較高（硫含量<5ppm)，易 貯存、運輸等優點，亦可在低溫下重組反應（約·c〜35(rc)，高 ❹溫型的燃料電池需操作在1，因此不適合應用在交通工具 上所以在小型燃料電池當中甲醇較其它碳氫化合更適合做氯氣 的來源，故目前應用最廣。 使肝醇重綠料提高安全性，但是仍有料地方有待改 =譬如應用縣㈣擎上啟動性與反應性太慢、設計大麵格 :貝播:科選擇性少、C〇含量過高等缺點，這都導致它無法商業 化’種種缺財待未來-_究改善。 200926497 完整的燃料重組系統中，不僅包括重組器、仍有高溫與低溫 轉移反應器以及co氧化器。這其中，為了避免c〇毒化燃料電池 之觸媒，因此設計重組***時必須盡量降低⑺濃度至1〇ppmA 下。2002年Gervasio提到’對於一個理想蒸氣重組反應，除了尋 找一個南氫產率的觸媒之外，也希望能將一氧化碳選擇率控制於 1%以下，之後再利用其它純化，如水氣轉移反應(WGSH)、部分氧 化選擇反應(PrOX)或其它反應將一氧化碳濃度降低至1〇ppm以下 〇 (Gervasio e_t al.，2002)，而避免一氧化碳毒化燃料電池組觸媒 (Oetjen et al.，1996; Mukerjee et al.，1999)。另外，重組器 的醇類濃度大於5000ppm時，亦會毒化電池組的陽極觸媒，因此 醇類的轉化率必須高於95 vol%，甚至99 vol%以上。 若重組反應的溫度高於30(TC時，觸媒容易產生劣化的情形， 但是溫度低於200°C時，則無法發揮銅觸媒的活性，因此，一般銅 觸媒於甲醇蒸氣重組反應的操作溫度約為2〇〇〜300°C。另外，當曱 ❹醇轉化率達百分之百時’如只考慮氫氣、一氧化複和二氧化碳， 則氫氣體積百分率應為75vol%，剩餘25vol%為C0及C〇2，比起部 分氧化反應最高40vol%、自動熱能重組反應50vol%的氫氣濃度高 出許多，故曱醇重組反應比起其它反應擁有此高濃度氫氣的優 勢’而且C0濃度最低(0. 3〜lvol%)，如此只須經過pr〇x反應即可 將C0濃度降至i〇ppm以下，可以省略WGSH反應步驟。 曱醇重組反應會因進料不同而有所改變，大致區分成： 200926497 (a)蒸氣重組反應(Steam Reforming Reaction，SR) 蒸氣重組反應是利用水蒸氣與一氧化碳反應取得(：〇2及H2，一 方面可提高氫氣產量，另一方面亦可減少C0產生。 CHsOH + H2O CO2 + 3H2 ΔΗ=+49. 7kJ/mol (1-1) 在（1-1)反應中，為了使曱醇和水蒸氣反應，所以必須在充分 吸熱環境下進行’這使得反應過程中需要外界提供熱能並加熱一 段時間，這使得利用此種反應所製成的燃料電池，無法在低溫條 Ο 件下快速啟動’加上得考慮絕熱效率，成本也相對提高，使得蒸 氣重組反應存在著很大的缺點(Ma et al.，2000>。 在（1-2)反應中，則屬於放熱反應，而隨著另一個水媒氣轉化 反應(water-gas-shift reaction，WGSR)，但所產生的熱氣仍無 法完全提供蒸氣重組反應(Peppley et al.，1999)。 CO + H2O ^ C〇2+H2 (WGSR), ΔΗ=-41. lkJ/mol (1-2) 在(1-3)反射，-氧化碳會經由甲醇分解反應(iflethan〇i ❹deco即osition reaction，MDR)產生，並且由於此反應速率最緩 慢’而為速率決定步驟(rate determining step)，故無法忽略 (Seiichiro et al.， 1999; Yasuyuki et al.， 1998)。 CH3〇H->CO + 2H2(MDR), ΔΗ=+92.〇 kJ/mol (1-3) WGSR *歷兩種方法都會使得反應變得相當複雜且難以控 制，為了能事先預測出產物濃度，針對重組反應在不同情況下的 反應動力學逐漸被重視’未來可利用速率動力式去賴產物濃 200926497 度，目前也正快速發展。 (b) 部分氧化反應（Partial Oxidation Reaction, P0R) CHaOH + 〇. 25〇2-> 〇. 5C0 +0. 5C〇2 +2H2 , ΔΗ=-50. 8kJ/mol (1-4) 整個（1-4)反應為放熱反應，反應會依不同曱醇及氧氣的比例 進行’氧的比例愈高’放熱愈劇烈，因此外界不需額外提供熱能， 預熱時間可忽略’反應加快；反應器的設計也比較簡單，僅考慮 〇 氡氣與進料的比例即可。雖說增加啟動時間，但是由於放熱使溫 度升高不利反應進行’轉化效果減弱，加上氧氣易與空氣中氮氫 形成NOx等化合物，氫氣產率降低。除此之外，反應亦會伴隨著 甲醇分解反應及C0與〇2的（1-5)與（1-6)燃燒反應 CH3〇H^CO + 2H2, ΔΗ=+92. 0 kJ/mol (1-5) CO + O2 CO2 , ΔΗ=-283. 0 kJ/mol (ΐ_β) 燃燒反應的放熱量更大，如果無法適時將熱量去除，反應受 ® 到限制情況更嚴重’加上溫度控制不易，反應速率常數易發生變 化，動力學推演的困難度也相對提高(Cubeiro et al., 1998; Edwards et al·， 1998)。 (c) 自動熱能重組反應(Autothermal Reforming Reaction, ATR) CHaOH + 〇.25〇2 +0. 5H2〇^C〇2 +2. 5H2 , ΔΗ=-71.4kJ/mol (1-7) 9 200926497 此反應器設計主要是將蒸氣重組和部份氧化反應(b)結合，一 方面可利用部份氧化反應產生的熱提供蒸氣重組反應所需，不再 由外界提供熱能，可加快重組反應速率；另一方面則利用蒸氣重組 帶來的高效率彌補整組反應器的效能，彼此有互補功效，也解決 了熱量得失問題。蒸氣重組反應被啟動後，調整曱醇、水蒸氣及 氧氣的比例’隨後反應可再轉化成高效能水蒸氣重組反應即可。 雖然看似簡單，但仔細觀察反應卻是錯綜複雜、變化多端，裡頭 ❹所含的反應機構多種’包含了上述所介紹的各種反應，如果要加 以控制，將會遇到不小困難，而且控制進料的設計成本也會相對 提高（Maetal·，1996)。 (d)電漿重組反應(Plasma Reforming Reaction，PR) '電漿重組器是利用熱電漿離子將短鏈碳氫化合物直接轟擊解 離成氫氣，因此基本上與使用之燃料種類無關，且不像一般觸媒 式重組器容易受到污染毒害。使用高動能電漿燃料分子鍵結打斷 €1需要大量能量’如分解甲烧⑽)之能量則為18kcal偏。通常一 個重組器都是希望要求能使用多種類的燃料才能達到多工的效 果’電漿重組ϋ具有這方面_點’不過太依魏力提供能量， 是最大的缺點（吳和生等人，2002)。 般來說，進行重減應時大錄用價格昂貴的貴重金屬（如 =RU等)作為觸媒，但是事實上觸媒可以連結於不同的擔體上， 使件其形紐展趨於錄化。目此，對f醇重岐應來說，就可 200926497 選用價格低廉的Cu/ZnO/AhO3作為觸媒。不過，不同觸媒製程對 觸媒活性也有相當的影響，因此尋找出觸媒在不同合成方法、環 境條件以及比例上調配的最大的效益為各界所追求的目標。 關於以Cu/ZnO/Al2〇3觸媒進行重組反應與脫氫反應、觸媒活性 衰退、觸媒合成，已有許多文獻存在，簡單介紹如下： 1995年’ Elliot等人利用共沉澱法合成出的Cu/Zn〇/Al2()3 可以將所產生的C0-H2進行大量水蒸氣重組反應轉變成c〇2_h2，因 〇 此幫助了減少C0生成，避免觸媒受到毒化且發現在銅鋅觸媒中添 加鋁的成份’對於觸媒的穩定性及壽命有明顯的提升。 2002年，¥〇1^&611等人發現(：11/211〇/^12〇3觸媒在水的比例增 加，約43%以上’有助於加速反應且可減少副產物dimethy丨e让從， methyl ether, methyl formate, methane 及一氧化碳的生成降至 1%以内；此外也提出反應過量的水分子及溫度提升，約高於· C溫度，可以有效的與碳原子鍵結，可防止積碳的現象。 © Cu/Zn0/Al2〇3觸媒於脫氫反應之應用 1911年’ Amphlett等人的研究中發現，其實曱醇合成反應與 甲醇蒸氣重組反應的逆反應是類似的。過去幾十年針對甲醇合成 方式已有許多相關研究發表，而以Cu/Zn〇為基礎觸媒對反應最具 有活性’雖然對於活性位置及Zn0角色扮演仍存有爭議，但一般 接受ZnO做為銅觸媒支稽材料。銅鋅觸媒也開始被使用於甲醇蒸 氣重組反應實驗及應用。 11 200926497 1989年，Cheng及Isogai等人在蒸氣重組反應中加入 Cu/ZnO/AhO3觸媒’發現除了貴重金屬觸媒之外，銅觸媒也為呈現 出高活性金屬；然而在反應時卻易產生衰退情形，主要原因在於其 低熔點（1083°C)，以致於發生燒結(sintering)現象，使得銅觸媒 表面積下降’反應位置減少。為了增加觸媒壽命，許多高溶點之 金屬氧化物，如Cn〇3、C〇0、ZnO及MgO等也被嘗試添加於銅觸媒 上來抑制燒結現象。 ❹ 丨970年，Klisurski等人用不同的單一金屬氧化物進行甲醇 氧化生一氧化碳反應’比較其活性。發現二氧化碳生產速率及二 氡化碳選擇率隨著觸媒還原性的增加而增加，氧化物順序為Cu〇 > C〇3〇4 > Mm〇3 > Ni 0 > Fe2〇3 > V2O5。 1988年’ Matsukata等人提出Cu/Al在曱醇水蒸氣重組反應 的活性是高於Cu/ZnO系觸媒。即使Cu/ZnO觸媒當時已被廣泛應 用於甲醇水蒸氣重組反應，並表現出不錯活性。 ❹ 1992年，kPe春人以2-丙醇脫氫為反應式，發現Zn0的加入 有助於提高轉化數(TOF，turnover frequency)，而會使還原溫度 稍微下降有利於Cu(n)的還原。而在450K〜540K反應時，會同時 有脫氫和脫水的反應存在，可能原因是氫與氡化鋅形成ZnH_〇H之 化合物’或Ζη2+-02存在於氧化鋁之擔體上有助於活化氫分子，因 此可能存在ΕΤ-ίΓ，H—有利於CuOl)變成Cu(0)，而低銅比例之 Cu/ZnO/Al2〇3觸媒活性較純銅觸媒為高，但若只有單獨的氧化辞存 12 200926497 在則沒^錄朗，故其推論應為鱗氧鱗的仙力。用不同 比例Cu/ZnO/Am為觸媒，發現反應溫度低於4概時此觸媒僅有 脫氫的活性，且速率常賴Cu⑻活性表面積成正比。所以認以〇) 為反應之活性中心。 1995年’ Elliot等人利用共沉澱法製備Cu/Zn〇/Al2〇3可以將 所產生的C0-H2進行蒸氣重組反應轉變成c〇H[J2，因此幫助了減少 C0生成，避免觸受到毒化且發_銅鋅觸中添加㈣成份， Ο 對於觸媒的穩定性及壽命有明顯的提升。 1998年’ Graeme等人發現銅辞觸媒含有較高的銅分散度、金 屬表面積及較小的活性觸媒粒徑，因此可得到高的甲醇轉化率。 在這些研究中Cu/ZnO觸媒則是利用不同比例的Cu(N〇3)2及 Zn(N〇3)2前趨物混合製備而成。 2001年’ Toyir等人利用含浸法製備cu/zn〇的觸媒用於甲醇 合成的反應上，ZnO有四項功用：（1)有AhO3的存在下，zn〇展現 ©耐高溫的功能且降低銅原子在高溫長時間的反應操作下所造成聚 集的現象;(2)使銅有較高的分散性；（3)使銅粒子不易被進料的 雜質(硫化物)所毒化;⑷抑制甲醇再轉變為二甲醚。而擔體種類 對活性的影響很人’ C0/H2合成甲醇而言，~活性之比較為200926497 IX. INSTRUCTIONS OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for synthesizing a ride, and more particularly to a method for synthesizing a catalyst for a battery recombiner. [Prior technology] 近年来 In recent years, due to the rise of awareness of environmental protection, coupled with the sharp decline in energy and the exhaustion of oil, people have to pay attention to the issue of energy crisis, making the fuel cell (Fuel ceii) of non-petrochemical energy more The more you pay attention. In the past few decades, the international fuel cell technology has made breakthroughs. In addition to the advantages of high efficiency, easy availability of raw materials and low pollution, fuel cells only generate heat and water in waste, which can greatly reduce air. Affected by pollution, this makes fuel cells the most promising way of energy. Because of this, fuel cells have gradually replaced traditional generators and internal combustion engines, and are widely used in power generation and transportation. Fuel cells have different types depending on electrolytes, such as PAFC, Phosphate Fuel Cell, Melt Carbonate Fuel Cell (MCFC), Solid Oxide Fuel Cell (SOFC), and protons. Exchange membrane type (PEMFC, Proton Exchange Membrane Fuel Cel 1) and the like. At present, PEMFC's so-called polymer electrolyte fuel cell (PEMFC) is the deepest researcher. The electrolyte is a fuel cell composed of a polymer film. The polymer 200926497 film is an insulator with a function of conducting hydrogen ions to isolate the cathode and anode. The reaction gas 'gas is usually hydrogen and oxygen. Up to now, the technology of proton exchange membrane fuel cells (PEMFC) for fuel cells below 1 kW is the most mature. Essential elements in fuel cells are oxygen and hydrogen. Oxygen can be taken directly to the large dry gas, and hydrogen can be produced by electrolysis using solar energy or hydroelectric power. However, due to environmental and technical difficulties, Wei New has broken through. In addition, the electrolysis reaction produces hydrogen which is difficult to store, and may be unstable or explosive in transport. Therefore, it is currently preferred to use a reformer in the fuel process (fuel pr〇cess〇r). Hydrocarbons (such as methyl 9, methanol, natural gas, light oil and other chlorinated alpha) are obtained by burning reaction, which can avoid the storage, filling and transportation of nitrogen in the safety, etc. It is necessary to fill the hydrocarbon persimmon in the reformer to produce hydrogen gas, and then the hydrogen gas is supplied to the fuel cell, and one gas port can be formed. Among the stone anti-wind compounds, the fuel quality of methanol is high (sulfur content < 5ppm), easy to store, transport, etc., and can also be recombined at low temperature (about · c ~ 35 (rc), high temperature type The fuel cell needs to operate at 1, so it is not suitable for use in vehicles. Therefore, methanol is more suitable for chlorine gas source than other hydrocarbons in small fuel cells, so it is the most widely used. It improves the safety of liver alcohol heavy green materials. However, there are still some areas to be changed = such as the application county (four), the start-up and reactivity is too slow, the design of the face: shelling: less selective, low C 〇 content, etc., which makes it impossible to commercialize Lack of money for the future - _ research improved. 200926497 Complete fuel recombination system, including not only recombiners, there are still high temperature and low temperature transfer reactors and co oxidizers. Among them, in order to avoid the poisoning of fuel cells, When designing the recombination system, it is necessary to reduce the concentration (7) to 1 〇ppmA as much as possible. In 2002, Gervasio mentioned 'for an ideal steam recombination reaction, in addition to finding a catalyst for the South hydrogen yield, The carbon monoxide selectivity can be controlled to less than 1%, and then other purifications such as water vapor shift reaction (WGSH), partial oxidation selective reaction (PrOX) or other reactions can be used to reduce the carbon monoxide concentration to less than 1 〇 ppm (Gervasio e_t al. , 2002), while avoiding carbon monoxide poisoning fuel cell catalysts (Oetjen et al., 1996; Mukerjee et al., 1999). In addition, when the recombiner has an alcohol concentration greater than 5000 ppm, it also poisons the anode catalyst of the battery. Therefore, the conversion rate of alcohol must be higher than 95 vol% or even 99 vol%. If the temperature of the recombination reaction is higher than 30 (TC, the catalyst is prone to deterioration, but when the temperature is lower than 200 ° C, then The activity of the copper catalyst cannot be exerted. Therefore, the operating temperature of the general copper catalyst in the methanol vapor recombination reaction is about 2 〇〇 to 300 ° C. In addition, when the sterol conversion rate is 100%, the hydrogen is only considered. For oxidation and carbon dioxide, the volume fraction of hydrogen should be 75 vol%, and the remaining 25 vol% is C0 and C 〇 2, which is much higher than the partial oxidation reaction up to 40 vol%, and the autothermal recombination reaction 50 vol% is much higher. The sterol recombination reaction has the advantage of having a high concentration of hydrogen compared to other reactions' and the C0 concentration is the lowest (0.3 to vol%), so that the C0 concentration can be reduced to below i〇ppm by only the pr〇x reaction. The WGSH reaction step is omitted. The sterol recombination reaction will vary depending on the feed, and is roughly divided into: 200926497 (a) Steam Reforming Reaction (SR) The steam recombination reaction is obtained by reacting water vapor with carbon monoxide (: 〇2 and H2, on the one hand, can increase hydrogen production, on the other hand, it can also reduce C0 production. CHsOH + H2O CO2 + 3H2 ΔΗ = +49. 7kJ/mol (1-1) In the (1-1) reaction, in order to react sterol with water vapor, it must be carried out under a sufficiently endothermic environment. It is necessary to provide external heat and heat for a period of time, which makes the fuel cell made by such a reaction unable to be quickly started under a low temperature strip. In addition, the adiabatic efficiency is considered, and the cost is relatively increased, so that the vapor recombination reaction exists. A big disadvantage (Ma et al., 2000). In the (1-2) reaction, it is an exothermic reaction, and with another water-gas-shift reaction (WGSR), The resulting hot gas still does not fully provide a vapor recombination reaction (Peppley et al., 1999). CO + H2O ^ C〇2+H2 (WGSR), ΔΗ = -41. lkJ/mol (1-2) at (1-3) ) Reflection, - Carbon monoxide is produced by the methanol decomposition reaction (iflethan〇i ❹deco or osition reaction, MDR), and because the reaction rate is the slowest, it is a rate determining step and cannot be ignored (Seiichiro et al) , 1999; Yasuyuki et al., 1998). CH3〇H->CO + 2H 2 (MDR), ΔΗ=+92.〇kJ/mol (1-3) WGSR * Both methods make the reaction quite complicated and difficult to control. In order to predict the product concentration in advance, the recombination reaction is different in different cases. The reaction kinetics under the gradual emphasis on the future utilization rate of the dynamic de-producting product concentration 200926497 degrees, is also rapidly developing. (b) Partial Oxidation Reaction (P0R) CHaOH + 〇. 25〇2-> ; 5C0 +0. 5C〇2 +2H2 , ΔΗ=-50. 8kJ/mol (1-4) The whole (1-4) reaction is an exothermic reaction, and the reaction will be carried out according to the ratio of different sterols and oxygen. The higher the ratio, the more intense the heat release, so there is no need to provide additional heat. The preheating time can be neglected. The reaction is quicker. The design of the reactor is relatively simple. Only the ratio of helium to feed can be considered. Time, but due to the exothermic temperature increase, the adverse reaction proceeds, the conversion effect is weakened, and the oxygen easily forms a compound such as NOx with nitrogen and hydrogen in the air, and the hydrogen yield is lowered. In addition, the reaction is accompanied by methanol decomposition reaction and C0 and 〇2 (1-5) and 1-6) Combustion reaction CH3〇H^CO + 2H2, ΔΗ=+92. 0 kJ/mol (1-5) CO + O2 CO2 , ΔΗ=-283. 0 kJ/mol (ΐ_β) Exothermic heat of combustion reaction Larger, if the heat is not removed in time, the reaction is more severely limited by the condition of 'the temperature is not easy to control, the reaction rate constant is easy to change, and the difficulty of dynamic deduction is relatively increased (Cubeiro et al., 1998; Edwards Et al., 1998). (c) Autothermal Reforming Reaction (ATR) CHaOH + 〇.25〇2 +0. 5H2〇^C〇2 +2. 5H2 , ΔΗ=-71.4kJ/mol (1-7) 9 200926497 The reactor design is mainly to combine the vapor recombination and the partial oxidation reaction (b). On the one hand, the heat generated by the partial oxidation reaction can be used to provide the steam recombination reaction, and the heat energy can no longer be supplied from the outside, and the recombination reaction rate can be accelerated; On the one hand, the high efficiency brought by steam recombination compensates the efficiency of the whole set of reactors, complement each other, and solves the problem of heat gain and loss. After the steam reforming reaction is initiated, the ratio of sterol, water vapor and oxygen is adjusted. Then the reaction can be converted into a high-performance steam reforming reaction. Although it seems simple, the observation of the reaction is complicated and varied. The various reaction mechanisms contained in the ❹ 包含 contain the various reactions described above. If you want to control it, you will encounter difficulties and control. The design cost of the material will also increase relatively (Maetal·, 1996). (d) Plasma Reforming Reaction (PR) 'The plasma recombiner uses thermal plasma ions to directly dissociate short-chain hydrocarbons into hydrogen, so it is basically independent of the type of fuel used, and unlike the general Catalytic reconstitutors are susceptible to contamination. The use of high kinetic energy plasma fuel molecular bonds to interrupt €1 requires a large amount of energy, such as the decomposition of A (10), and the energy is 18kcal. Usually a recombiner wants to use a variety of fuels to achieve the multiplex effect. 'Plastic recombination has this aspect _ point' but too much energy is provided by Wei Li, which is the biggest disadvantage (Wu et al., 2002) . Generally speaking, the reduction of expensive precious metals (such as =RU, etc.) is used as a catalyst, but in fact, the catalyst can be connected to different supports, so that the shape of the exhibition tends to be recorded. . For this reason, for the case of heavy alcohol, it is possible to use inexpensive Cu/ZnO/AhO3 as a catalyst for 200926497. However, different catalyst processes have a considerable impact on the activity of the catalyst. Therefore, it is the goal pursued by the public to find the maximum benefit of the catalyst in different synthesis methods, environmental conditions and proportions. There are many literatures on the recombination reaction and dehydrogenation reaction, catalyst activity decay and catalyst synthesis with Cu/ZnO/Al2〇3 catalyst. The following is a brief introduction: In 1995, Elliot et al. synthesized by coprecipitation. The Cu/Zn〇/Al2()3 can convert the produced C0-H2 into a large amount of steam reforming reaction into c〇2_h2, which helps reduce the formation of C0, avoids poisoning of the catalyst and is found in copper and zinc. The addition of aluminum to the media has a significant increase in the stability and longevity of the catalyst. In 2002, ¥〇1^&611 and others found that (the ratio of 11/211〇/^12〇3 catalyst in water increased, about 43% or more' helped to accelerate the reaction and reduced by-product dimethy丨e The production of methyl ether, methyl formate, methane and carbon monoxide is reduced to less than 1%; in addition, excessive reaction of water molecules and temperature rise, which is higher than · C temperature, can be effectively bonded to carbon atoms, which can prevent Carbon deposition phenomenon © Cu/Zn0/Al2〇3 catalyst for dehydrogenation reaction 1911 'Amphlett et al. found that the reverse reaction of sterol synthesis reaction with methanol vapor recombination reaction is similar. Ten years of research on methanol synthesis has been published, and Cu/Zn〇 is the most active catalyst for the reaction. Although there is still controversy about the active site and Zn0 role play, ZnO is generally accepted as a copper touch. Media support materials. Copper-zinc catalysts have also begun to be used in methanol vapor recombination experiments and applications. 11 200926497 In 1989, Cheng and Isogai et al. added Cu/ZnO/AhO3 catalyst in steam recombination reaction to find in addition to precious metals. touch In addition to the medium, the copper catalyst also exhibits a highly active metal; however, it is prone to decay during the reaction, mainly due to its low melting point (1083 ° C), so that sintering occurs, making the copper catalyst The decrease in surface area reduces the reaction site. In order to increase the lifetime of the catalyst, many high-melting point metal oxides such as Cn〇3, C〇0, ZnO and MgO have also been tried to be added to the copper catalyst to suppress the sintering phenomenon. In 970, Klisurski et al. used different single metal oxides for methanol oxidation to produce carbon monoxide. 'Compared to its activity. It was found that the carbon dioxide production rate and the carbon dioxide selectivity increased with the increase of catalyst reducibility. The order of oxides was Cu〇> C〇3〇4 > Mm〇3 > Ni 0 > Fe2〇3 > V2O5. 1988 'Matsukata et al. proposed that the activity of Cu/Al in the rehydration reaction of sterol water vapor is higher than that of Cu /ZnO-based catalyst. Even Cu/ZnO catalyst has been widely used in methanol steam reforming reaction and showed good activity. ❹ In 1992, kPe spring people dehydrogenated with 2-propanol as the reaction formula and found Zn0. Joining helps The conversion number (TOF, turnover frequency) will make the reduction of the reduction temperature favor the reduction of Cu(n). In the reaction of 450K~540K, there will be both dehydrogenation and dehydration reactions, possibly due to hydrogen and helium. Zinc-forming ZnH_〇H compound 'or Ζ 2+ 2+ -02 exists on the support of alumina to help activate hydrogen molecules, so there may be ΕΤ-ίΓ, H—favors CuOl) to become Cu(0), and low The Cu/ZnO/Al2〇3 catalyst activity of copper ratio is higher than that of pure copper catalyst. However, if there is only a single oxidation term, 200926497 is not recorded, so the inference should be the Xianli of scales and oxygen scales. Using different ratios of Cu/ZnO/Am as catalyst, it was found that the catalyst had only dehydrogenation activity when the reaction temperature was lower than 4, and the rate was often proportional to the active surface area of Cu(8). Therefore, it is recognized as the active center of the reaction. In 1995, Elliot et al. used coprecipitation to prepare Cu/Zn〇/Al2〇3 to convert the produced C0-H2 into a vapor recombination reaction to c〇H [J2, thus helping to reduce C0 formation and avoid poisoning. And the addition of _ copper and zinc to the (four) component, Ο has a significant improvement in the stability and life of the catalyst. In 1998, Graeme et al. found that copper catalysts contain high copper dispersion, metal surface area and small active catalyst particle size, thus providing high methanol conversion. In these studies, Cu/ZnO catalysts were prepared by mixing different ratios of Cu(N〇3)2 and Zn(N〇3)2 precursors. In 2001, Toyir et al. used the impregnation method to prepare cu/zn〇 catalyst for methanol synthesis. ZnO has four functions: (1) in the presence of AhO3, zn〇 exhibits the function of high temperature resistance and reduces The phenomenon of aggregation of copper atoms under high temperature and long-term reaction operation; (2) high dispersibility of copper; (3) poisoning of copper particles which are not easily contaminated by impurities (sulfide); (4) inhibition of methanol It is then converted to dimethyl ether. The effect of the type of the carrier on the activity is very good. For the synthesis of methanol in C0/H2, the comparison of ~ activity is
Cu/ZnQ/Al.CZA) >Cu/ZnO/Si()2(CZS) >Cu/ZnQ/活性碳(CZC)，但 對CO/H2/C〇2則較無影響。Cu/ZnQ/Al.CZA) >Cu/ZnO/Si()2(CZS) >Cu/ZnQ/activated carbon (CZC), but has no effect on CO/H2/C〇2.
Cu/ZnO/A12〇3觸媒活性衰退Cu/ZnO/A12〇3 catalyst activity decline
X 13 200926497 1989年’ Cheng及IS0gai等人提出觸媒退化的原因為銅分子 的燒結，其產生原因主要是在高溫狀態⑽^左右），銅分子間的 阻抗降低，銅分子互相聚集而形成顆粒較大銅粒子。此燒結會使 得觸媒活f·生基粒控變大，表面積減少，直接得影響觸媒活性。因 此有不少鮮家研究如何防止此縣發生，除了將溫度降低之 外增加或改變促進劑成為被討論的對象。許多高熔點之金屬氧 化物，如Cn〇3、Co0、Zn0及Mg〇等也被嘗試添加於_媒上來抑 ❹制燒結現象，以增加觸媒壽命。 1995年，lswasa等人發現對於觸媒活性退化，主要由於兩個 因素’-個是銅的燒結現象，另一個則是積碳累積。其中當含碳 物質被加齡解時會造成積韻產生，它触财鱗活性基位 置被佔據以及孔洞堵塞’碳沉積在觸媒及表面，而碳的形成涉及 I多變的物理及化學結構，有石墨及其餘晶狀態，比較特別的 是’在某些擔體或是小顆粒的金屬觸媒上會出現呈絲狀積碳，長 度皆小於0.5⑽而且金屬麵存會在絲狀的積碳的頂端，伴隨 成長。如前所提，水的比例增加，約百分之50以上，有助於加速 反應並減州餘產生，此収親量的水分子在咖。c以上，可 以有效的與碳原子鍵結’可防止積碳的現象。 - 2005年KaWamura等人利用共沉澱法製備⑽麟吣觸媒， 指出觸媒活性油表面積有關，當加入Zn〇之後會提高銅金屬的 分散度而增加活性。另夕卜也指出PH值對觸媒活性有相關影塑，當 200926497 ρΗ=8· 8時，溶液中ΟΙΓ增加’能有效阻止銅金屬聚集成銅礦且分 解銅結晶結構使活性與穩定度增加。 2005年Agrwal等人研究中指出積碳作用產生時會覆蓋銅金 屬活性位置，造成甲醇脫附，進而使重組反應速率下降。其中利 用 XPS(X-ray Photoelectron Spectroscopy)分析出主要積碳物質 為石墨與C〇3。X 13 200926497 1989 'Cheng and IS0gai et al. proposed that the cause of catalyst degradation is the sintering of copper molecules, which is mainly caused by high temperature (10)^), the impedance between copper molecules decreases, and copper molecules aggregate to form particles. Larger copper particles. This sintering causes the activity of the catalyst to be increased, and the surface area is reduced, which directly affects the activity of the catalyst. Therefore, many fresh families have studied how to prevent this county from happening, except that the increase or change of the accelerator is the object of discussion. Many high melting point metal oxides, such as Cn〇3, Co0, Zn0 and Mg〇, have also been tried to be added to the sintering medium to suppress the sintering phenomenon to increase the catalyst life. In 1995, lswasa et al. found that the degradation of catalyst activity was mainly due to the fact that two factors were the sintering of copper and the accumulation of carbon. When the carbonaceous material is aged, it will cause the accumulation of rhyme, which is occupied by the active scale of the scaly scale and the pores are blocked. Carbon is deposited on the catalyst and surface, and the formation of carbon involves the physical and chemical structure of I. There are graphite and other crystal states, and it is particularly special that 'the filaments will be formed on the metal catalyst of some of the supports or small particles, the length is less than 0.5 (10) and the metal surface will be in the filamentous product. The top of the carbon grows with it. As mentioned above, the proportion of water increases by more than 50%, which helps to accelerate the reaction and reduce the amount of water produced by the state. Above c, it can be effectively bonded to carbon atoms to prevent carbon deposition. - In 2005, KaWamura et al. used co-precipitation method to prepare (10) linden catalyst, which indicated that the surface area of the catalyst active oil was related. When Zn ruthenium was added, the dispersion of copper metal was increased to increase the activity. In addition, it also pointed out that PH value has a related effect on the activity of the catalyst. When 200926497 ρΗ=8·8, the increase of niobium in the solution can effectively prevent the copper metal from accumulating into the copper ore and decompose the crystal structure of the copper to increase the activity and stability. . In the 2005 study by Agrwal et al., it was pointed out that carbon deposition occurred when it covered the active sites of copper metal, causing methanol desorption, which in turn reduced the rate of recombination. Among them, XPS (X-ray Photoelectron Spectroscopy) was used to analyze the main carbonaceous materials as graphite and C〇3.
Cu/ZnO/Al2〇3觸媒合成 ❹ 1996年，Jingfa等人利用草酸共沉澱法製備（：11/211〇/^12〇3進 行C〇2與H2合成甲醇的反應’發現可以得到較高活性。在製備過程 中，銅與鋅之間產生作用，可生成同晶形狀的銅辞粒子，此種結 構的結晶對於曱醇合成反應有重要的影響。 1997年，Sun等人提出銘的加入可使銅鋅粒子進一步形成更 小的非晶向的粒子，它們不僅使得活性提高，也增加了甲醇的選 擇率。主要因為它能提升10〜60%銅粒子的表面積。 ® 1997年，JinSfa等人利用草酸共沉澱法製備Cu/ZnO/Al2〇3進 行C〇2與H2合成曱醇的反應’發現可以得到較高活性。在製備過程 中，銅與鋅之間產生作用，可生成同晶體形狀的銅鋅粒子，此種 結構的結晶對於甲醇合成反應有重要的影響。之後，同年Sun提 出，鋁的加入可使銅鋅粒子進一步形成更小的非晶向的粒子，它 們不僅使得活性提高，也增加了甲醇的選擇率。主要因為它能提 升10〜60%銅粒子的表面積。 15 200926497 〇年’ Ma等人開始針對觸媒合成過程中，鍛燒氧化的 對觸媒树影響。其中發現觸媒經分段的鍛燒後活性提高，並且 比較氧氣、空纽聽作為鍛減料，氧氣可制較好結果。 推論分段魄可戦加細域敝，糾觸職結，而氧氣便 從中扮演更多及更好的氧化劑的角色。 2〇〇1年’ Wensheng等人利用SEM、、勘等相關儀器觀察 草酸共沉澱法及尿素沉澱法合成Μ··表面結構，可發現 ❹後者銅粒子易於鋅表面聚集，造成銅表面積下降，除此之外，測 反應活性時，也得到較差結果。 2002年’么£^11等人利用微乳化法製造(^11/211〇當觸媒，而 此法與傳統的共沉澱法比較，在BET的表面積上，微乳化法(3〇_7〇 wt% Cu)其表面積為22〜36 m2/g低於共沉澱法所製之觸媒的册τ 表面積（約60m2/g) ’然而微乳化法所製備之觸媒在甲醇部份氧化 的反應上顯現高的氫氣及二氧化碳選擇性。當在〇2/CH3〇H (莫耳比) ❾=〇. 1時’利用微乳化觸媒做反應’在185〇c時就開始有氫氣的產 生’然而沉殿法所製備觸媒在同一狀況下做反應卻是在2151才開 始有氫氣的生成’而在TPR實驗中得知利用微乳化法製備銅鋅觸 媒’其還原波峰會有拖曳現象，他們認為是因為少有的銅和氧化 鋅間有強烈的交互作用（strong interact ion)所致。 2005年，鐘順章發現以草酸共沉澱法製得銅觸媒分散性佳， 所製知觸媒的重量百分比為Cu/ZnO/Al2〇3=15:15:5,另外又找出在 16 200926497 最佳溫度240°C下，得到甲醇轉化率為97. 6%，氫氣產生速率為〇打 mole/h/g，濃度為58. 89 ν〇1%，一氧化碳產生逮率為2 4朗 mmole/h/g ’ 濃度為 〇. 2163 vol%。 為了讓燃料電池能夠被應用至攜帶型電子叢置中，因此目前 迫切需要發展攜帶型重組H，此攜帶型重組_為微型燃料重^ 器（miCr〇_ref〇rmer)。為了將此應用在筆記型電腦中，重組反應 必須具備低溫、啟動快速且反應活性高之條件，其中必要條件為 ❹在反應溫度.22〇Τ下，甲醇轉化率大於9〇%，一氧化碳濃产在 1%以下，氫氣濃度則在50%以上。因此，很明顯地可以發覺辰ς順 ，所提出_媒合成方法，雖歸有著相料好的反應結果，但 是其最佳溫度為240Χ，並不適合於攜帶型重組器。為此，本發明 主要的在於碰下找出最符合微麵料纽_狀觸媒。 此外’在文獻中主要是以固定溫度高溫下锻燒與還原銅觸 媒’但是這卻容易使得銅金屬燒結。為改善此問題，在本發明方 去中’主要是採用多段式升溫，而避免此問題產生。另外，以空 氣為載流氣體能大幅提高二氧化碳選擇率。 【發明内容】 本發明主要目的在於，探討用Ce與以改質Cu/Zn_晶觸 媒並探时在固定Cu/Zn〇/A12〇3觸媒重量比為時，對於 曱醇重組反應的影響。 在本發明觸媒合成方法中，仍採用草酸共沉殿法，但先探討 17 200926497 以不同pH值製備Cu/ZnO/AhO3觸媒，並以氫氣的產生速率為標 準，得到最適化的反應之銅觸媒。接者，添加第四種金屬（Ce、Cr) 於Cu/ZnO/AhO3觸媒中’尋找出200T低溫下最佳反應活性。 於反應時則控制觸媒量為2〜0. 3g、進料組成H2〇/CH3〇H莫耳 比為1. 2、反應溫度200°C至26(TC及重量時空速率(WGSH，weight hourly space velocity)6.13(l/h)的條件下，載氣選擇為空氣， 其含量為20 SCCM。並將觸媒以ASAP(BET)、XRD、TPR、SEM等儀 〇 器進行觸媒特性的鑑定，以便鏗別最佳條件參數。 由不同pH值製備Cu/ZnO/AlzO3觸媒進行甲醇蒸氣重組反庳 可發現以pH 7擁有最大產氫濃度64. 4vol%，此觸媒活性最佳，bet 測得最大觸媒表面積為41.13m2/g，銅觸媒活性面積為7. 62m2/g cat. ’觸媒粒徑為2· 40nm，分散度為6. 25%，活性值(Aa)為175. 0 mmol/h/g cat.與週轉頻率（T0F)為 〇. 115s-1。 以製備pH 7之Cu/ZnO/Al2〇3觸媒為基礎添加ce〇2與Cr2〇3時， © 而得知加入Ce〇2,會對一氧化碳濃度有抑制作用，這主要在於Ce〇2 能使水氣轉移反應往逆反應進行。添加Cr2〇3能提高曱醇轉化使得 在甲醇重組反應在觸媒重量百分比Cu/ZnO/A12〇3/ει·2〇3= 1 & 1 ϋ 1 的作用下，於反應溫度20(TC時曱醇轉化率為91· 7%，氳氣濃度為 5〇· 5vol%，產氫速率為〇· 524mol/h/g ’ 一氧化碳濃度為 〇. 323vol% ’ 一氧化碳生成速率為2· 66mmol/h/g，二氧化碳選擇率 為98. 5%為最佳反應狀態’在觸媒性質鑑定方面’銅粒子粒徑為 18 200926497 U5nm，分散度為8·灌’活性值為175. 5咖〇1物眺與轉化 頻率為0.255s_1。 _於本發明之優點與精神可以藉由以下的發明詳述及所附圖 式得到進一步的瞭解。 【實施方式】 在本發明燃料電池觸媒的合成方法中，主要是加入金屬（可為 © Ce或Cr)至Cu/ZnO/AhO3 ’而進行觸媒合成，以增強燃料電池的甲 醇自熱式重組反應（主要是對一氧化碳濃度有抑制作用、在低溫下 提高甲醇轉化率）。不過，影響觸媒在反應過程中的活性大小與製 備過程中許多變因有關’例如pH值、煅燒溫度、還原溫度與篩析 觸媒篩網(mesh)數，或者放大製備觸媒產量等，因此底下除了清 楚說明燃料電池觸媒的合成方法以外，更會提出最佳的製程參數。 草酸共沉澱法合成觸媒： ❹ 1.將 Cu(N〇3)2 · 2. 5H2O、Zn(N〇3)2.6H2O、A1 (N〇3)3 · 9H2〇、Cr(N〇3)3. 9M)與Ce(N〇3)3 · 6H2〇在室溫下分別溶於乙醇中配製成1 hoi/jjj3 溶液後，取適當比例混合為100 cm3溶液且授拌均勻，使觸媒 〇11/211/^1/^6((：1')重量百分比為15:15:5:0〜10。 2·混合溶液與過量20%的草酸(1 kmol/m3)反應’使沉澱作用完全。 3.使用氨水(25%腿3)將混合溶液pH值控制在pH 6〜pH 8。 4·將沉澱物經由抽氣過濾法過濾且置於100°C烘箱中烘乾μ小 時，其中乾燥目的在於去除物理吸附的水分子。 19 200926497 5.將乾燥之觸顧行_析步驟，峨控侧媒職大小，其筛網 mesh數為60〜80之間。 觸媒在το成之剛必須經過煅燒步驟，此步驟目的在於使硝，酸銅 經由熱分解形絲蝴，❹卜增_翻機械強度與強化 金屬鋪賴伽力。本實驗使祕（⑽（:m3/min )，並藉 由程式升溫方式锻燒觸媒先驅物，其程式升溫步驟如下·· 開始-^15(Γ(： __^15(rc」^2〇忙 腦。c © -^^250°C -^>250〇C -^^300°C 3〇〇°C 〇 7.最後利用⑽祕（刚cm3/min )還原觸媒，使氧化銅還原 成銅，其中升溫步驟為： 開始一!i£m^30(rc j、t >3〇(rc。 以草酸共沉澱法合成出觸媒之後’首先將觸媒放置在直徑lcm 長度為15cm石英管，再將此石英管置入電熱加熱式反應床，藉由 熱電偶探測且控制溫度。其中觸媒重量為〇. 2〜〇. 3g，此外在石英 Φ 管中於觸媒上方及下方放置石英棉。觸媒下方石英棉可固定觸媒 位置，而觸媒上方石英棉則具有避免觸媒在反應過程中喷出之功 用。 使用進料為曱醇與水的混合溶液，其中水/曱醇莫耳比為 1 · 2。藉由注射幫浦注射曱醇水溶液進入反應器中，注射速率為2. 2 cm3/h。起初甲醇水溶液先進入蒸發器（13〇°c)蒸發成氣體且混合均 勻後，接著進入觸媒反應床中，反應溫度控制在200〜300T之間且 20 200926497 在大氣壓下反應。經過觸媒反應之後連接冷凝管使得未反應完的 甲醇冷凝下來，並且氣體繼續通入氣相層析儀分析混合氣體。在 過程中以電熱式加熱帶與絕熱棉包裹管路，避免液體在管路中遇 到空氣中的冷空氣而冷凝。 在重組反應中’對於選擇載氣之考量，一般多使用惰性氣體 做為曱醇重組反應之攜帶氣體，如氦氣、氮氣等，以避免載氣參 與反應，但是不管使用何種惰性氣體’一但使用將會使成本及重 ® 量提高，因此若能設法利用空氣來取代，則載氣取自於大自然， 如此不僅可以降低成本’而且也不用擔心會有诮耗殆盡的問題。 為此，在本發明重組反應中，可使用空氣為載流氣體，其流量為 20SCCM (cm3/min) ’其中氧氣與曱醇莫耳比為〇. 269。其中對於甲 醇來說’計算出重量時空速率（Space velocity )為6.13服別 (weight hourly space velocity，h_1 )。 請參閱第1A〜1C圖，第1A〜1C圖為本發明參數條件之示意圖。 _ 如第1Α圖所示，在反應溫度為240Τ下，不同pH值對甲醇重組反 應的影響。由此圖可發現pH值對於甲醇轉化率以及二氧化礙選擇 率上並無明顯改變，都能維持在95%以上，但是在氫氣濃度上有較 明顯的差異。pH 7之觸媒相較於PH 6觸媒與pH 8之觸媒能提高 氫氣濃度至64.4vol%，因此PH 7之觸媒是較佳的參數條件之一。 第1B圖為固疋Cu/ZnO/AhO3含量15:15:5時，在不同Ce〇2含 量下，對於反應溫度之變化圖。由圖可知隨著溫度增加，甲醇轉 21 200926497 化率會提高’而氫氣濃度與一氧化碳濃度也會增加，因此二化碳 選擇率則會下降。其中也可看出Ce〇2含量對於重組反應的影響， Ce〇2含量增加則曱醇轉化率提高，但是相較於Cu/Zn〇/Al2〇3觸媒來 說’對甲醇轉化率上並無幫助。此外，經檢測發現，在Cu/ZnO/Al2〇3 觸媒中加入Ce〇2並沒有提高銅的分散度，而且可以發現以〇2加入 反而增強ZnO的結晶結構使得觸媒表面積下降，造成反應性不佳。 此外’可得知一氧化碳濃度隨溫度增加，上升趨勢較 ❹ Cu/Zn〇/Al2〇3觸媒低’因此造成二氧化碳選擇率較高，其中主要原 因在於Ce〇2添加可加速水氣轉移反應的逆反應。2〇〇6年patel與 Pant提出相同理論’ Cu/ZnO/A 1A觸媒中加入Ce〇2能使得水氣轉 移反應偏向逆反應進行。另外也提出Ce〇2於還原步驟中，會將部 份Ce〇2還原成Ce，當甲醇重組反應進行時會產生〇2幫助積碳氣 化’因此積碳作用較小，穩定性高。 在氫氣產生方面，與甲醇轉化率具有相同趨勢，皆隨溫度上 #升而上升’且反應溫度到達240T時，氫氣濃度與產生速率到達穩 定值。但是仍不及Cu/ZnO/Ah〇3觸媒之氫氣濃度與產率。整體而 e ’ Ce〇2含量為l〇wt%時與Cu/ZnO/AhO3觸媒有相同活性，包括曱 醇轉化率、氫氣濃度與氫氣產生速率，而唯一不同點在於加入⑽ 能降低一氧化碳濃度與產生速率’此結果對於甲醇重組器而言很 重要，過多的一氧化碳會毒化燃料電池之電極，因此必須控制一 氡化碳濃度越小越好，最低標準在1%以下。而Cel〇觸媒在溫度 200926497 260°C下’一氧化碳濃度僅〇. 336vol%遠小於Cu/ZnO/Al2〇3觸媒 〇·716 vol%。 第1C圖為固定Cu/ZnO/Al2〇3含量15:15:5時在不同Cn〇3含量 下對於反應溫度之變化圖。圖中得知隨溫度增加甲醇轉化率、氫 氣濃度、一氧化碳濃度皆會增加，而二氧化碳選擇率則下降。比 較不同CnCb含量對重組反應的影響可知Cn〇3加入對甲醇轉化率 有幫助，Cu/ZnO/AhOa/CnO3觸媒能在低溫下進行重組反應時使轉 化率緩慢下降，因此對於氳氣產生速率而言能保持一穩定值，但 是相對於-氧化碳生成量來看’比起Gu/ZnQ/Al2()3觸有偏高的 趨勢。而隨著㈣3含量的增加’甲醇轉化率下降，反而不利於重 组反應進行’在纽H巾過量的情也會毒化電極，因此最低甲 醇轉化率必須達到寶以上才符合微量型燃料重級器之標準。_ 對於二氧化碳選料上可看$ ’⑽在二氧化碳選擇率上 •隨著溫度增加下降趨勢較為緩和。和在於當&增加時，觸媒， 的_會形成與CuCr〇4 · 2Cu〇幫助甲醇直接氧化成二氧化石 與水（wang et al.，2002)。因此造成二氧化碳選擇率較高。 圖中可歸納出-結杲，鉻的添加有利於甲醇轉化 =對於一氧化碳生成並沒有__，因此可知反應路徑上偏南 2甲醇裂解聽，餅情轉城—概额域岐率增加。 :體而言，⑽含量不可太高，Crl觸媒在2帆反應時甲物 率月b到達9L 7%’氫氣濃度為5〇. 5賴，一氧化碳為〇爲⑽ 23 200926497 * 二氧化碳選擇率為98. 5%為最佳反應狀態。與圖3-8 XRD圖譜相比 對有相同結果’ Crl觸媒鋼粒徑最小，分散度最佳，因此反應性最 好。 由以上實驗數據可知，Cr2〇3添加比起&仏更具有反應性，因 此比較CnCb含量對於反應性的影響，找出最佳以2〇3含量。 含置過辦f轉化率0聰下降，*二氧化碳珊率祕持穩定 不下降’氫氣濃度隨著含量增加也趨於—穩定值。所以得知 ❹ Crl擁有最佳反應活性。 藉由以上較佳具體實施例之詳述’係希望能更加清楚描述本 發明之舰與精神’而並非以上述賴露的較佳具體實施例來對 本發明之齡加嫌制。城地，其目的鱗魏各種改變 及具相等性的安排於本發明所欲申請之專利範圍的範嘴内。 【圖式簡單說明】 Λ 第1Α〜1C圖為本發明參數條件之示意圖。 【主要元件符號說明】 無 24Synthesis of Cu/ZnO/Al2〇3 Catalysts In 1996, Jingfa et al. used oxalic acid coprecipitation to prepare (: 11/211〇/^12〇3 for the reaction of C〇2 with H2 to synthesize methanol). In the preparation process, copper and zinc have an effect, which can produce copper crystal particles of the same crystal shape. The crystal of this structure has an important influence on the sterol synthesis reaction. In 1997, Sun et al. The copper-zinc particles can be further formed into smaller amorphous particles, which not only increase the activity, but also increase the selectivity of methanol. Mainly because it can increase the surface area of 10 to 60% of copper particles. ® 1997, JinSfa et al. The preparation of Cu/ZnO/Al2〇3 by oxalic acid coprecipitation method for the reaction of C〇2 with H2 to synthesize sterols has been found to have higher activity. In the preparation process, copper and zinc have an effect and can form the same crystal. The shape of copper-zinc particles, the crystal of this structure has an important influence on the methanol synthesis reaction. Later, in the same year, Sun proposed that the addition of aluminum can further form copper-zinc particles into smaller amorphous particles, which not only enhance the activity. It also increases the selectivity of methanol, mainly because it can increase the surface area of 10~60% copper particles. 15 200926497 The following year, Ma et al. began to influence the catalytic catalyst of calcination oxidation in the process of catalyst synthesis. It is found that the activity of the catalyst is improved after segmentation of calcination, and oxygen and air are used as forging and reducing materials, and oxygen can produce better results. Inferior segmentation can be added to the fine field, the tactile knot, and oxygen It will play the role of more and better oxidants. 2〇〇1年' Wensheng et al. used SEM, investigation and other related instruments to observe the oxalic acid coprecipitation method and urea precipitation method to synthesize the surface structure of Μ·· Copper particles tend to aggregate on the zinc surface, causing a decrease in the surface area of copper. In addition, when the reactivity is measured, poor results are also obtained. In 2002, it was produced by microemulsion method (^11/211〇catalyst). Compared with the conventional coprecipitation method, the microemulsion method (3〇_7〇wt% Cu) has a surface area of 22~36 m2/g lower than that of the coprecipitation method. Book τ surface area (about 60m2/g) 'However, microemulsification The prepared catalyst exhibits high hydrogen and carbon dioxide selectivity in the partial oxidation of methanol. When 〇2/CH3〇H (mole ratio) ❾=〇.1 'reacts with microemulsified catalyst' Hydrogen production began at 185 ° C. However, the catalyst prepared by the Shen Dian method reacted under the same conditions but hydrogen production began in 2151. In the TPR experiment, it was found that copper was prepared by microemulsification. Zinc catalysts have a drag phenomenon in their reduction peaks, which they believe is due to the strong interaction between copper and zinc oxide. In 2005, Zhong Shunzhang found that the copper catalyst was prepared by the co-precipitation method of oxalic acid, and the weight percentage of the known catalyst was Cu/ZnO/Al2〇3=15:15:5, and the best was found at 16 200926497. At a temperature of 240 ° C, the methanol conversion rate was 97.6%, the hydrogen production rate was beaten mole / h / g, the concentration was 58. 89 ν 〇 1%, the carbon monoxide production rate was 2 4 langmmole / h / The concentration of g ' is 〇. 2163 vol%. In order to enable the fuel cell to be applied to a portable electronic cluster, there is an urgent need to develop a portable recombination H, which is a micro-fuel refiller (miCr〇_ref〇rmer). In order to apply this in a notebook computer, the recombination reaction must have the conditions of low temperature, rapid start-up and high reactivity. The necessary condition is that the reaction rate is 〇Τ at the reaction temperature of .22〇Τ, the methanol conversion rate is more than 9〇%, and the carbon monoxide is rich. Below 1%, the hydrogen concentration is above 50%. Therefore, it is obvious that Chen Yushun can be found. The proposed method of synthesizing the medium has a good reaction result, but its optimum temperature is 240 Χ, which is not suitable for a portable recombiner. To this end, the main purpose of the present invention is to find the most suitable micro-materials. Further, in the literature, calcined and reduced copper catalysts are mainly used at a fixed temperature and high temperature, but this easily causes the copper metal to be sintered. In order to improve this problem, in the present invention, the multi-stage heating is mainly employed to avoid this problem. In addition, the use of air as a carrier gas can greatly increase the carbon dioxide selectivity. SUMMARY OF THE INVENTION The main object of the present invention is to investigate the recombination reaction of sterols when Ce and the modified Cu/Zn_crystal catalyst are combined to fix the Cu/Zn〇/A12〇3 catalyst weight ratio. influences. In the catalyst synthesis method of the present invention, the oxalic acid co-precipitation method is still used, but firstly, 17 200926497 is used to prepare Cu/ZnO/AhO3 catalyst at different pH values, and the optimum reaction is obtained by using the hydrogen generation rate as a standard. Copper catalyst. In addition, a fourth metal (Ce, Cr) was added to the Cu/ZnO/AhO3 catalyst to find the optimum reactivity at 200T. In the reaction, the amount of the catalyst is controlled to be 2~0. 3g, the composition of the feed is H2〇/CH3〇H molar ratio is 1. 2. The reaction temperature is 200°C to 26 (TC and weight hourly rate (WGSH, weight hourly) Space velocity) Under the condition of 6.13 (l/h), the carrier gas is selected as air, and its content is 20 SCCM. The catalyst is identified by ASAP (BET), XRD, TPR, SEM, etc. In order to identify the optimal conditions, the Cu/ZnO/AlzO3 catalyst prepared from different pH values can be found to have a maximum hydrogen production concentration of 64. 4 vol% at pH 7. The maximum catalyst surface area is 41.13 m2/g, and the copper catalyst active area is 7.62 m2/g cat. 'The catalyst particle size is 2·40 nm, the dispersion is 6.25%, and the activity value (Aa) is 175. 0 mmol/h/g cat. and the turnover frequency (T0F) is 115. 115s-1. When adding ce〇2 and Cr2〇3 based on the Cu/ZnO/Al2〇3 catalyst prepared at pH 7, © It is known that the addition of Ce〇2 will inhibit the concentration of carbon monoxide, which is mainly because CeC2 can make the water gas transfer reaction go to the reverse reaction. Adding Cr2〇3 can increase the conversion of sterol so that the reaction in methanol is in contact with Weight percentage Cu/ZnO/A12〇3/ει·2〇3= 1 & 1 ϋ 1 under the action of reaction temperature 20 (TC conversion of sterol is 91·7%, helium concentration is 5〇· 5% vol. In terms of catalyst property identification, the copper particle size is 18 200926497 U5nm, the dispersion is 8 · irrigation' activity value is 175. 5 curry 1 substance and conversion frequency is 0.255s_1. _ The advantages and spirit of the present invention can be borrowed The following detailed description of the invention and the accompanying drawings are further understood. [Embodiment] In the method for synthesizing the fuel cell catalyst of the present invention, a metal (which may be Ce or Cr) to Cu/ZnO/AhO3 is mainly added. 'The catalyst synthesis is carried out to enhance the methanol autothermal recombination reaction of the fuel cell (mainly inhibiting the concentration of carbon monoxide and increasing the methanol conversion rate at low temperatures). However, it affects the activity of the catalyst during the reaction. Many factors related to the preparation process, such as pH, calcination Temperature, the temperature of the reduction catalyst and sieve analysis mesh (mesh) number, or other amplifying catalyst preparation yield, and therefore clearly described below in addition to the synthetic method of the fuel cell other than the catalyst, it will propose the best process parameters. Synthesis of Catalyst by Oxalic Acid Coprecipitation: ❹ 1. Cu(N〇3)2 · 2. 5H2O, Zn(N〇3)2.6H2O, A1 (N〇3)3 · 9H2〇, Cr(N〇3) 3. 9M) and Ce(N〇3)3 · 6H2〇 are dissolved in ethanol at room temperature to prepare 1 hoi/jjj3 solution, then mix in a proper ratio to 100 cm3 solution and mix evenly to make the catalyst 〇11/211/^1/^6((:1') The weight percentage is 15:15:5:0~10. 2. The mixed solution reacts with an excess of 20% oxalic acid (1 kmol/m3) to make precipitation 3. Use ammonia water (25% leg 3) to control the pH of the mixed solution at pH 6~pH 8. 4. The precipitate is filtered by suction filtration and dried in an oven at 100 ° C for μ hours. The purpose of drying is to remove the physically adsorbed water molecules. 19 200926497 5. The dryness of the contact is analyzed, and the size of the screen mesh is between 60 and 80. The catalyst is in the το成之刚. It must be subjected to a calcination step. The purpose of this step is to make the nitrate, acid copper through the thermal decomposition of the silk, and to increase the mechanical strength and strengthen the metal. This experiment makes the secret ((10) (: m3 / min), and by Temperature-programmed calcination catalyst precursor, its process The temperature rise step is as follows: · Start -^15 (Γ(: __^15(rc"^2〇 busy brain. c © -^^250°C -^>250〇C -^^300°C 3〇〇 °C 〇7. Finally, use (10) secret (just cm3/min) to reduce the catalyst, and reduce the copper oxide to copper. The heating step is: Start one! i£m^30(rc j, t > 3〇(rc After synthesizing the catalyst by oxalic acid co-precipitation, the catalyst is first placed in a quartz tube with a diameter of 15 cm and a length of 15 cm. The quartz tube is placed in an electrothermal heating reaction bed, and the temperature is detected by a thermocouple. The weight of the medium is 〇. 2~〇. 3g, in addition, quartz wool is placed above and below the catalyst in the quartz Φ tube. The quartz cotton under the catalyst can fix the position of the catalyst, while the quartz cotton above the catalyst has the catalyst to avoid The function of the squirting during the reaction. The feed is a mixed solution of decyl alcohol and water, wherein the water/sterol molar ratio is 1.25. The injection pump is injected into the reactor by injecting a sterol aqueous solution at an injection rate of 2. 2 cm3 / h. Initially the methanol aqueous solution first enters the evaporator (13 ° ° C) and evaporates into a gas and mixes well, then enters the catalyst reaction bed, the reaction The degree is controlled between 200 and 300 T and 20 200926497 at atmospheric pressure. After the catalyst reaction, the condensation tube is connected to condense the unreacted methanol, and the gas continues to pass through the gas chromatograph to analyze the mixed gas. The electric heating belt and the insulating cotton wrap the pipeline to prevent the liquid from condensing in the pipeline encountering the cold air in the air. In the recombination reaction, for the selection of carrier gas, inert gas is generally used as a carrier gas for sterol recombination reaction, such as helium gas, nitrogen gas, etc., to avoid the carrier gas participating in the reaction, but no matter what inert gas is used. However, the use will increase the cost and the amount of weight, so if you can try to use air instead, the carrier gas is taken from nature, so you can not only reduce the cost, but also don't worry about the exhaustion. To this end, in the recombination reaction of the present invention, air may be used as a carrier gas having a flow rate of 20 SCCM (cm3/min), wherein the oxygen to sterol molar ratio is 〇. For the methanol, the space velocity is calculated as the weight hourly space velocity (h_1). Please refer to FIGS. 1A to 1C, and FIGS. 1A to 1C are schematic diagrams showing the parameter conditions of the present invention. _ As shown in Figure 1, the effect of different pH values on methanol recombination reaction at a reaction temperature of 240 。. From this figure, it can be seen that the pH value does not change significantly with respect to methanol conversion rate and selectivity of oxidizing, and can be maintained above 95%, but there is a significant difference in hydrogen concentration. The catalyst of pH 7 can increase the hydrogen concentration to 64.4 vol% compared with the catalyst of pH 6 catalyst and pH 8, so the catalyst of PH 7 is one of the better parameter conditions. Fig. 1B is a graph showing changes in reaction temperature at different Ce 〇 2 contents when the Cu/ZnO/AhO3 content is 15:15:5. It can be seen from the figure that as the temperature increases, the methanol conversion rate will increase and the hydrogen concentration and carbon monoxide concentration will increase, so the carbon dioxide selectivity will decrease. It can also be seen that the CeC2 content has an effect on the recombination reaction, and the Ce〇2 content increases the sterol conversion rate, but compared to the Cu/Zn〇/Al2〇3 catalyst, the conversion to methanol is No help. In addition, it was found that the addition of Ce〇2 to the Cu/ZnO/Al2〇3 catalyst did not increase the dispersion of copper, and it was found that the addition of 〇2 enhanced the crystal structure of ZnO, resulting in a decrease in the surface area of the catalyst. Poor sex. In addition, it can be seen that the concentration of carbon monoxide increases with temperature, and the upward trend is lower than that of ❹Cu/Zn〇/Al2〇3 catalyst. Therefore, the carbon dioxide selectivity is higher. The main reason is that the addition of Ce〇2 can accelerate the water-gas shift reaction. Reverse reaction. In 2〇〇6 years, Patel and Pant put forward the same theory. The addition of Ce〇2 to the Cu/ZnO/A 1A catalyst can make the water vapor shift reaction biased toward the reverse reaction. It is also proposed that in the reduction step, Ce 〇 2 will reduce the portion of Ce 〇 2 to Ce, and when the methanol recombination reaction proceeds, 〇 2 will be generated to help carbon deposition gasization. Therefore, the carbon deposition effect is small and the stability is high. In terms of hydrogen production, the methanol conversion rate has the same tendency as the temperature rises by #升, and when the reaction temperature reaches 240T, the hydrogen concentration and the production rate reach a stable value. However, it is still not as good as the hydrogen concentration and yield of the Cu/ZnO/Ah〇3 catalyst. When the content of e ' Ce〇2 is l〇wt%, it has the same activity as Cu/ZnO/AhO3 catalyst, including sterol conversion rate, hydrogen concentration and hydrogen generation rate, but the only difference is that adding (10) can reduce carbon monoxide concentration. And the rate of production' This result is important for methanol recombiners. Too much carbon monoxide poisons the electrodes of fuel cells, so it is necessary to control the concentration of carbon monoxide to be as small as possible, with a minimum standard of less than 1%. The Cel 〇 catalyst at temperature 200926497 260 ° C 'carbon monoxide concentration is only 〇 336 vol% is much smaller than Cu / ZnO / Al2 〇 3 catalyst 〇 · 716 vol%. Figure 1C is a graph showing the change in reaction temperature at different Cn〇3 contents when the Cu/ZnO/Al2〇3 content is fixed at 15:15:5. It is shown that the methanol conversion rate, the hydrogen concentration, and the carbon monoxide concentration increase with increasing temperature, while the carbon dioxide selectivity decreases. Comparing the effects of different CnCb contents on the recombination reaction, it is known that the addition of Cn〇3 is helpful for the conversion of methanol. The Cu/ZnO/AhOa/CnO3 catalyst can slowly reduce the conversion rate when the reaction is carried out at low temperature, so the rate of helium production is slow. In this case, it is possible to maintain a stable value, but it has a tendency to be higher than that of Gu/ZnQ/Al2()3 relative to the amount of carbon monoxide produced. With the increase of (4)3 content, 'methanol conversion rate decreases, but it is not conducive to the recombination reaction. 'In the case of excessive amount of Ni-H towel, the electrode will be poisoned, so the minimum methanol conversion rate must reach above Bao to meet the micro-type fuel re-leveler. standard. _ For carbon dioxide material selection, see $ ’(10) in carbon dioxide selectivity. • The downward trend is more moderate with increasing temperature. And when & increases, the catalyst, _ will form with CuCr〇4 · 2Cu〇 to help methanol directly oxidize to dioxide and water (wang et al., 2002). This results in a higher carbon dioxide selectivity. The figure can be summarized - crusting, the addition of chromium is conducive to methanol conversion = there is no __ for the formation of carbon monoxide, so it can be seen that the reaction path is southerly than the methanol cracking listens, and the pie-to-city-probability domain increases the rate. In terms of body, the content of (10) should not be too high. When the Crl catalyst reacts in 2 sails, the rate of material A reaches 9L 7%. The hydrogen concentration is 5〇. 5 赖, carbon monoxide is 〇 (10) 23 200926497 * Carbon dioxide selectivity 98. 5% is the best reaction state. Compared with the XRD pattern in Figure 3-8, the same results were obtained. The Crl catalyst steel has the smallest particle size and the best dispersion, so the reactivity is the best. From the above experimental data, it is known that the Cr2〇3 addition is more reactive than & ,, so the effect of the CnCb content on the reactivity is compared to find the optimum content of 2〇3. The conversion rate of 0 is reduced, the concentration of carbon dioxide is stable, and the concentration of hydrogen is not decreased. The concentration of hydrogen tends to be stable with increasing content. So we know that ❹ Crl has the best reactivity. The above description of the preferred embodiments is intended to more clearly describe the ship and spirit of the present invention, and is not to be construed as a preferred embodiment of the invention. The city, its various scales of change and equality are arranged in the mouth of the patent scope of the invention to be applied for. [Simple description of the diagram] Λ The first to the 1C diagrams are schematic diagrams of the parameter conditions of the present invention. [Main component symbol description] None 24