(1. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，410083 長沙；
2. 中南大學(xué) 粉末冶金國家重點實驗，410083 長沙；
3. 江西省環(huán)境工程職業(yè)學(xué)院，342000 贛州)
摘 要: 提出了超富集植物的“焚燒→濕法提取與凈化→電化學(xué)沉積/化學(xué)沉淀法→金屬/化工產(chǎn)品”工藝。以鎳的超富集植物Berkheya coddii為例，對該收獲物進(jìn)行焚燒處理后，對焚燒產(chǎn)物進(jìn)行氨法浸出，對浸出液進(jìn)行一定處理后直接進(jìn)行電積鎳，最終得到高純鎳板(99.999%)，該工藝既實現(xiàn)了對超富集植物收獲物的去毒化處理，又實現(xiàn)了收獲物中有價金屬的回收。對于浸出實驗，優(yōu)化實驗條件分別為：浸出溫度60 ℃，氯化銨及氨水的摩爾比(n(NH4Cl)׃n(NH3))0.6，液固比(L/S)5׃1，浸出時間2 h；對于鎳電積實驗，優(yōu)化實驗條件為：ρ(Ni2+)濃度23 g/L，極距3.5 cm；電流密度200 A/m2，溫度40 ℃。
關(guān)鍵字: 超富集植物；Berkheya coddii；資源化利用；浸出；電沉積
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Environmental Engineering Vocational College, Gangzhou 342000, China）
Abstract: The leaching and electrowinning of nickel from Berkheya coddii biomass was studied according to incineration→hydro-extraction and purification→electrodeposition→Metal/product flowsheet, and ammonia-ammonium chloride solution was used as leaching agents. The research was carried out in two phases, which are a leaching study to determine nickel extraction efficiency of this leaching agent, and an electrowinning study to determine nickel electrodeposition efficiency from the filtrate. The results show that leaching temperature has the most dominant effect on the metal extraction performance, followed by mole ratio of NH4Cl to NH3, liquid-solid ratio and leaching time. Accordingly, the optimum leaching conditions are that temperature of 50 ℃, n(NH4Cl)׃n(NH3)=0.6, leaching time of 2 h and L/S=5׃1. The total nickel removal after leaching under optimum condition reaches to 97.61%. The optimum conditions of nickel electrodeposition experiments are obtained as ρ(Ni2+) of 23 g/L, polar distance of 3.5 cm, current density of 200 A/m2 and temperature of 40 ℃, and the ultimate nickel content in the as-synthesized nickel plate is more than 99.999%.
Key words: hyperaccumulator; Berkheya coddii; resource utilization; leaching; electrowinning
