著者

下川 公博 手塚 大輔 鹿田 慧 邑瀬 邦明 杉村 博之 粟倉 泰弘

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan (ISSN:18816118)

巻号頁・発行日

vol.129, no.2, pp.72-77, 2013-02-01

参考文献数

28

被引用文献数

4

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The surface smoothness, S and Ag content of electrodeposited copper were investigated to clarify the influence of chloride ions on electrorefining using hydrochloric acid and SbCl<SUB>3</SUB>. The surface smoothness of electrodeposited copper was improved with increasing amounts of hydrochloric acid and SbCl<SUB>3</SUB> as well as lower S and Ag content. The tensile strength and elongation of the electrodeposited copper were also studied to determine if they could be used as criteria for evaluating the cathode strippability in the permanent cathode process. The tensile strength and elongation increased when the total concentration of chloride ions released from hydrochloric acid and SbCl<SUB>3</SUB> was 20 mg/L. Metallographic observations indicated that lower rate of twin crystal formation resulted in higher tensile strength and elongation at approximately 20 mg/L of chloride ion concentration.

著者

糟野 貴史 北田 敦 下川 公博 邑瀬 邦明

出版者

一般社団法人 資源・素材学会

雑誌

日本鑛業會誌 (ISSN:18816118)

巻号頁・発行日

vol.130, no.2, pp.65-69, 2014

被引用文献数

6

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Electrolytic copper contains, on average, 10 ppm silver as impurity, which leads to a loss of silver as a cashcow product for copper smelters.Most of silver included in blister copper anodes passes into anode slime when electrolyzed, keeping the elemental state. However, once a part of elemental silver dissolves from the anode or from anode slime for some reason, then silver can co-deposit with electrolytic copper cathode, since silver is nobler than copper. In the present work, the dissolution behavior of silver from anode slime was examined by using granular silver as a model of the slime.We have shown that the silver dissolution is caused by dissolved oxygen in the electrolyte, and that thiourea and/or chloride ions as usual additives play a role to suppress the silver dissolution approximately to two thirds.Moreover, it was found that the dissolution of silver was suppressed to less than 1ppm by galvanic contacting of the granular silver with less noble metals (Pb or Cu) immersed in the same electrolyte. This indicates that the use of Pb or Cu lining at the bottom of electrolytic cells can suppress silver dissolution from the anode slime settled to the bottom, reducing the silver loss to electrolytic copper.