環境

[3301-10-09] Galvanic interaction between aluminum and pyrite under various conditions

^○セン ソペア¹、小嶌 源也¹、タベリン カーリット¹、伊藤 真由美¹、広吉 直樹¹ (1. 北海道大学)

司会: 飯塚淳（東北大学）

キーワード：ガルバニック相互作用、アルミニウム、黄鉄鉱

Pyrite oxidation is the main cause of acid mine drainage. It is an electrochemical process that requires the transfer of electrons from a lower redox potential material to a higher one. In this study, the effects of aluminum on pyrite oxidation were investigated. Galvanic interaction could occur upon the attachment of aluminum metal to pyrite surface resulting in the suppression of pyrite oxidation. Leaching experiments were conducted by mixing pyrite and aluminum suspensions of various pulp densities in a constant temperature water bath (25⁰C). The results showed that sulfuric acid generated by pyrite oxidation was suppressed in the presence of metallic aluminum. The oxidation of pyrite was further suppressed when aluminum metal was pre-treated with 0.16M NaCl and 0.01M HCl prior to the leaching experiments. This indicated that the removal of aluminum oxide layer on the aluminum surface improved the electrical contact between aluminum and pyrite, which promoted galvanic interaction.