電子產業技術蓬勃發展，製程時所排放之二次液體中含大量重金屬其也包括高值有價金屬，若重金屬進入河流與地下水，後果將不堪設想；另一研究目的為廢棄電路板回收，許多研究者將廢棄電路板視為一座亟待開採之金礦，其內所含之高值金屬有如黃金，若不處理止直接進行掩埋或露天堆存，只會造成其環境汙染與有用物質之大量浪費。相反的，若將此廢棄電路板視為二次資源，可減少礦石開採、冶煉、加工成形所消耗之能源與資源。故於「回收與減量」其二次排放遺留物，將符合資源循環利用、綠色環境製程與促進國內永續經濟之發展。
本研究利用常壓輝光放電電漿(Atmospheric Pressure Glow Discharge Electrolysis，APGDE)，打破國內此技術僅應用於奈米材料合成，達相較傳統化學與物理法處理二次液體之技術快速、效率高、無二次汙染生成，符合目前迫切所需之綠色製程宗旨。研究初期以純水為起始測試液體進行APGDE系統於反應槽內之製程操作參數最佳化，並以光學發射光譜儀(Optical Emission Spectroscopy, OES)確認APGDE之內部電漿物種分析，其結果Nitrogen之特徵峰值會造成水中COD上升，經後續即時分析發現水中會產生Nitrate硝酸根；硝酸根對環境會刺激藻類與水中植物生長，造成優養化問題，本研究針對此一問題提出密閉式之反應槽，解決大氣中氮氣會因氣體迴旋關係捲入電漿噴射束中，其結果符合預期，即時OES監測電漿物種定性分析與硝酸根離子選擇電極儀器監測硝酸根生成之情況都指出此密閉反應槽有著良好之結果，無Nitrogen之特徵峰值產生亦無Nitrate硝酸根生成，其結果保留了常壓輝光放電電漿電解之特有峰值，並改善其缺點；OES結果可發現於309 nm有OH radical peak，此根peak為過氧化氫來源之一，其他如656.3 nm之Hydrogen alpha、777 nm之O peak，這些亦為臨場(in-situ)製備過氧化氫之主要來源。後續提出電漿與純水液體接面(Plasma-Liquid Interface, PLI)反應機制，建立以APGDE製程技術處理水溶液所臨場(in-situ)製備之過氧化氫(H2O2)溶液相關化學反應；而後於此參數配置不同濃度之含銀離子硝酸水溶液於APGDE製程應用之操作參數最佳化，其包含1000 ppm與10 ppm以下，藉感應耦合電漿原子發射光譜儀(Inductively Coupled Plasma, ICP-AES)分析其所配置之含銀離子硝酸水溶液經APGDE循環回收綠色製程處理後之回收效率圖，並查詢相關法規符合排放標準(Emission standard)，於低濃度部分樣品可達排放標準，於高濃度可達回收率98%；藉XRD (X-ray diffraction)、掃描式電子顯微鏡(SEM)分析其經APGDE循環綠色回收製程所還原之金屬顆粒結晶度與形貌，藉XRD分析結果可望達純金屬結果且無任何雜訊生成，SEM結果顯示在不同製程參數下有銀顆粒與奈米銀線之形貌，奈米銀線將可用於低溫銀膠之固含量材料使用，後以應用於硫酸銀與四氯金酸溶液，證明此技術不僅可應用於硝酸銀，亦可針對不同金屬作綠色回收處理，針對上述之各項結果提出本研究循環材料經濟之應用價值。

Electronic industries are causing the subsequent pollution of local coastal waters in Taiwan. Some of the waste water from the industry was contained noble metals. The remedation of metals brings considerable challenge since these noble metals, according to their chemical properties, can never be degraded but only stabilized. Therefore our research team set out to find an efficient, rapid and inexpensive method which is called “atmospheric pressure glow discharge plasma (APGDE)” by which to collect such valuable metals from the contaminated waters. The waste printed circuit boards is also a popular topic in the field of environment protection and resource recycling. We believe the re-utilization of waste printed circuit boards can be potential which process by our critical materials technologies. As mentioned above, establishment of a platform for research and development on the recovery process on Valuable Metals from the metal-containing wastewater of electronics industries by a Green Process of atmospheric pressure glow discharge plasma technology (APGDE).
The study is to address the technology of atmospheric pressure glow discharge plasma (APGDE) applied in the recovery of precise metals from the waste solution. The novel idea using APGDE for wastewater treatment is also proved for the in-situ preparation of hydrogen peroxide solution, which can be used to facilitate the reduction of metal ions in the solution and also be beneficial to oxide the cyanide-contained solution. The illegal discharge process of cyanide-contained solution is a quite tough problem occurred in the whole world. Thus, the in-situ treatment to metal-contained cyanide solution gives several advantages for the practical applications, such as quick and safe process without secondary discharge to the environment. As well, the recovery mechanism of in-situ preparation by APPJ dealing with the metal-contained cyanide solution is also proposed accordingly. Until now, the recovery efficiency has reached to a high value around 99% for high concentration Ag-contained solution (1000 ppm). For the low concentration Ag-contained solution below 10 ppm, the final concentration for the discharge process has passed the standard value. After consulting the Industries about the promising results for dealing with the metal-contained and toxic wastewater. We can conclude the feasibility for treating wastewater is achieved as a new novel green process.

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