化學鎳老化液電解回收鎳之研究

Electrolysis recovery of nickel from spent electroless nickel plating solution

林廷育(Ting-yu Lin)

指導教授 ： 王文裕

朝陽科技大學/理工學院/環境工程與管理系/碩士(2011年)

摘要

鎳具有致癌作用，也是一種短缺昂貴的金屬資源，近年來鎳金屬價格飆漲，生產成本比例增加。因此，化學鍍鎳廢液的處理相當重要，如處理不當，既是資源浪費，又可能導致重金屬污染。本研究使用電解法來電解化學鍍鎳的老化廢液，使老化液中的鎳能夠回收再利用；有別於傳統的化學混凝沉澱法，產生大量含鎳汙泥，後續的固化及掩埋處理費用又相當的龐大。
本研究先配製模擬化學鎳老化廢液，陽極分別使用RuO2/Ti網及IrO2/Ti網之不溶性陽極（dimensionally stable anodes, DSA）；陰極分別使用不鏽鋼及泡沫鎳進行比較。電解反應參數有溶液pH、電解時間、陰陽極的極板間距及溶液溫度等，找尋最佳電解參數，再應用於實廠化學鎳老化廢液的電解反應。各參數下電解效率的變化，陽極使用RuO2/Ti高於IrO2/Ti；隨溶液pH增高（7~11）而降低；極板間距（1~5cm）在3cm時最佳；溶液溫度（50~90）在80℃時最佳。陰極使用泡沫鎳時，鎳的去除率可達94%；而陰極使用不鏽鋼時，可將化學鎳老化廢液中的鎳沉積於不鏽鋼上，經過長時間的電解，可輕易的將鎳剝落，以達到電解回收鎳的目標，降低鎳對環境的衝擊。

關鍵字

化學鎳老化廢液 ； 化學混凝沉澱 ； 電解回收 ； 泡沫鎳 ； 不溶性陽極

並列摘要

Nickel is a really rare and expensive metal, and it can cause cancer. Nickel''s price is getting higher recently and the production cost is increasing, and therefore it is really important to take care of spent electroless nickel plating solution. If the spent solution is treated improperly, it would not only cause heavy metal contamination, but also resource wasting. The focus of this study is on the adoption of electrolysis method to recover nickel from spent electroless nickel plating solution. Unlike traditional chemical precipitation method which causes large amount of nickel sludge and expensive solidified treatment cost sequentially.
At first, simulated spent nickel solution was used in this study. Anodes are two types of dimensionally stable anodes (DSA) including RuO2/Ti mesh and IrO2/Ti mesh, respectively. Cathodes are stainless steel and nickel foam, respectively. The electrolysis process parameters including electrolysis time, solution pH, space between anode and cathode and solution temperature. Spent nickel solution generation from electroless nickel plating factory was used in electrolysis process sequentially. The temporal varieties of electrolytic efficiencies are studied throughout each process parameter. The results showed RuO2/Ti is better than IrO2/Ti. The electrolytic efficiencies decrease as solution pH increase within the range from 7 to 11. The best space between anode and cathode is 3cm within the range from 1 to 5cm. The best solution temperature is 80℃ within the range from 50 to 90cm. Nickel''s removal ratio can be as high as 94% using nickel foam as cathode. The recovered nickel foils can be easily peeled using stainless steel as cathode.

並列關鍵字

spent electroless nickel plating solution ； chemical precipitation ； dimensionally stable anodes ； electrolysis recovery ； nickel foam

參考文獻

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