(云南大學(xué) 化學(xué)系，昆明 650091)
摘 要: 用旋轉(zhuǎn)圓盤法在相同的實(shí)驗(yàn)條件下，對金、銀、銅的氰化溶解速率進(jìn)行比較研究。當(dāng)氰化鈉濃度為5.00 g/L、圓盤轉(zhuǎn)速為600 r/min、溫度為30 ℃時(shí)，獲得表觀速率常數(shù)的順序?yàn)椋?/SPAN>Au＜Ag＜Cu。在氰化鈉溶液中加入微量硫化鈉后，硫離子抑制氰化反應(yīng)的影響程度則為：Au＞Ag＞Cu。分析討論了電化學(xué)反應(yīng)機(jī)理，提出了相應(yīng)的觀點(diǎn)并對實(shí)驗(yàn)結(jié)果進(jìn)行了解釋。
關(guān)鍵字: 金；銀；銅；氰化溶解；硫離子
copper and influences of sulfion on them
（Department of Chemistry, Yunnan University, Kunming 650091, China）
Abstract:The cyanidation rates of gold, silver and copper were compared with each other under the same reaction conditions by kinetic rotating disk method, and the influences of sulfion on them were discussed. The results show that when the three metals react at ρ(NaCN) of 5.00 g/L, 600 r/min and 30 ℃, the obtained apparent rate constants for cyanide dissolution of three metals accord with the order of Au＜Ag＜Cu. However, when sodium sulfide is added into the cyanide solutions in advance, the decrease ratios of cyanide dissolution rates of the three metals accord with the order of Au＞Ag＞Cu. The reaction thermodynamics and mechanism based on the electrochemical theory were discussed, and some new explanations for experimental phenomena were proposed.
Key words: gold; silver; copper; cyanidation; sulfion
