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采用三电极体系研究了金及其伴生元素银、铜、镍和铁在硫脲中的阳极行为，详细考察了金在碱性硫脲溶液中阳极极化的各种影响因素，并对碱性介质中硫脲的稳定剂进行了选择。结果表明，只要硫脲在碱性介质中稳定存在，碱性硫脲可以实现金的选择性溶解；阳极电位是影响碱性硫脲溶金的关键因素，过高的阳极电位和温度易于导致硫脲的不可逆分解，而产生钝化金表面的元素硫；亚硫酸钠可以有效地抑制碱性硫脲的不可逆分解，大大提高金在碱性硫脲溶液中的阳极极化。
The anode behavior of gold and its associated elements silver, copper, nickel and iron in thiourea was investigated by using a three-electrode system. Various influencing factors of anodic polarization of gold in alkaline thiourea solution were investigated in detail. The thiourea stabilizer in the media was chosen. The results indicate that alkaline thiourea can selectively dissolve gold as long as thiourea is stable in alkaline medium. Anodic potential is the key factor that affects the dissolution of basic thiourea. Anodic oxidation of alkaline thiourea tends to lead to sulfur The irreversible decomposition of urea and the elemental sulfur on the passivating gold surface can be avoided. Sodium sulfite can effectively inhibit the irreversible decomposition of basic thiourea and greatly enhance the anodic polarization of gold in alkaline thiourea solution.