Corrosion and stress corrosion cracking behavior of alloys in solutions relevant to gold thiosulfate leaching technology

硫代硫酸金浸出技术相关溶液中合金的腐蚀和应力腐蚀开裂行为

• 批准号: 437892-2012
• 负责人: Alfantazi, Akram
• 金额: $ 5.1万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=553170
• 关键词: Corrosion; stress; corrosion; cracking; behavior

Hydrometallurgical processes for metal extraction deal with waste solution treatment and significant research isdedicated to improving the processes in terms of environmental issues. Gold hydrometallurgical extraction is currentlybeing performed bycyanide leaching. Due to personnel safetyand environmental issues, there is significant interest for replacing the cyanide leaching agent with thiosulfate. Barrick Gold Corporation is interested in developing the new leaching agent for their cyanide gold leaching process. The assessment of corrosion behavior of materials in concentrated thiosulfate solutions is an obstacle since no previous studyhas been performed in this medium. The overall objective of this proposal is to provide data on corrosion behavior of construction materials in thiosulfate solutions relevant to gold leaching. The final practical goal will be to decide on the alloys with the best performance in terms of chemical stabilityand stress corrosion cracking. In fundamental level, this will appreciablycontribute to the corrosion science since there is no data on corrosion behavior in concentrated thiosulfate solutions. This is particularlyimportant because of 1) interactions of thiosulfate with the surface leading to generation of sulfur and consequentlypromoting stress corrosion cracking; and 2) solution chemistryand the complications resulting from buffering capacityof thiosulfate. The innovative electrochemical techniques to be used in this studywill contribute to close the corrosion science gap in this particular environment.A PhD student, a post doctoral fellow and four summer students will be trained in this research project. This studywill help understanding the corrosion phenomenon in highlyconcentrated thiosulfate solutions. It will greatlyhelp deciding the best construction materials for this medium, which will finallyaccelerate the transition from the current cyanide-based leaching plants to more environmentally-friendlythiosulfate plants.

金属提取的湿法冶金工艺涉及废液处理，并且大量研究致力于改善环境问题方面的工艺。目前，金的湿法冶金提取采用氰化物浸出的方式进行。由于人员安全和环境问题，人们对用硫代硫酸盐替代氰化物浸出剂产生了浓厚的兴趣。巴里克黄金公司有兴趣为其氰化金浸出工艺开发新型浸出剂。对浓硫代硫酸盐溶液中材料腐蚀行为的评估是一个障碍，因为以前没有在这种介质中进行过研究。该提案的总体目标是提供与金浸出相关的硫代硫酸盐溶液中建筑材料的腐蚀行为数据。最终的实际目标是选择在化学稳定性和应力腐蚀开裂方面具有最佳性能的合金。从根本上讲，这将对腐蚀科学做出重大贡献，因为没有有关浓硫代硫酸盐溶液中腐蚀行为的数据。这一点尤其重要，因为 1) 硫代硫酸盐与表面的相互作用导致硫的生成，从而促进应力腐蚀开裂； 2）溶液化学和硫代硫酸盐缓冲能力引起的复杂性。本研究中使用的创新电化学技术将有助于缩小这一特定环境下的腐蚀科学差距。一名博士生、一名博士后研究员和四名暑期学生将在该研究项目中接受培训。这项研究将有助于了解高浓度硫代硫酸盐溶液中的腐蚀现象。它将极大地帮助确定该介质的最佳建筑材料，最终加速从当前的氰化物浸出厂向更环保的硫代硫酸盐厂的转变。