(1. 江西理工大學 冶金與化學工程學院，贛州 341000；
2. 北京礦冶研究總院，北京 102206)
摘 要: 針對高硅鈷白合金結(jié)構(gòu)復(fù)雜、難以直接硫酸浸出問題，開展堿焙燒脫硅預(yù)處理研究以破壞穩(wěn)定致密的硅鐵合金結(jié)構(gòu)。結(jié)果表明：經(jīng)堿焙燒預(yù)處理后，鈷白合金形貌發(fā)生明顯改變。堿焙燒條件如下：溫度600 ℃，NaOH用量為硅、鐵反應(yīng)所需理論量0.64倍。在上述條件下焙燒2 h后，所得渣經(jīng)水洗，硅的脫除率達到66.57%；再經(jīng)常壓硫酸浸出，鈷、鐵浸出率均高達99%以上，而銅則完全保留在浸出渣中，實現(xiàn)了鈷和銅分離，渣中的銅經(jīng)第二段氧化浸出得以回收。進一步基于工藝礦物學分析，對堿焙燒脫硅預(yù)處理后鈷白合金的常壓浸出行為進行解析。
關(guān)鍵字: 鈷白合金；堿焙燒；脫硅；預(yù)處理；常壓浸出
（1. School of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology,
Ganzhou 341000, China;
2.Beijing General Research Institute of Mining and Metallurgy, Beijing 102206, China）
Abstract:The refractory high-silicon cobalt white alloy is difficult to be leached directly by sulfuric acid because of its complex structure. The pretreatment of alkali-roasting and desilication was carried out to destroy the stable ferro-silicon alloy structure. The results show that the alloy structure is changed greatly after alkali-roasting and 66.57% of silicon can be removed by water-washing after the alkali-roasting at 600 ℃ for 2 h. The optimum dosage of NaOH for alkali-roasting is 0.64 times of the theoretical amount for the reactions of silicon and iron with NaOH. After the desilication, more than 99% of cobalt and iron can be leached from the pretreated alloy while all of copper is kept in the residue during the atmospheric leaching, by which the ideal separation of cobalt from copper is achieved easily. The copper in the residue can be recovered by the second stage oxidative leaching. Based on the mineralogical analysis, the leaching behavior of pretreated alloy was further discussed.
Key words: cobalt white alloy; alkali roasting; desilication; pretreatment; atmospheric leaching
