Lyotropic ion effects in interfacial phenomena in mineral processing

矿物加工中界面现象中的溶致离子效应

• 批准号: 261199-2007
• 负责人: Pawlik, Marek
• 金额: $ 1.92万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365315
• 关键词: Lyotropic; ion; effects; interfacial; phenomena

The physicochemical methods of mineral processing, such as froth flotation, rely on several related interfacial phenomena occurring at the mineral-solution interface. Polymer and surfactant adsorption, surface charging, particle-air bubble attachment, and aggregation/dispersion of particles are known to be a function of pH and ionic strength. While the term ionic strength has traditionally been used to denote the total electrolyte concentration in processing water, it does not take into account some specific effects, commonly referred to as lyotropic effects, that result from differences in ionic sizes.In terms of their effect on the surrounding water structure, all ions can broadly be divided into two groups: kosmotropes (water-structure making ions) and chaotropes (water-structure breaking ions). Only recently, has the potential impact of ionic size effects on the interfacial water structure and the associated interfacial phenomena been fully recognized but their significance in mineral processing applications has never been systematically studied. The main long-term objective of the proposed research is to determine the role of lyotropic effects in the fundamental interfacial phenomena, and to demonstrate how such effects can be controlled or manipulated to improve the performance of the froth flotation process.The experimental program will include a wide range of techniques and methods, from simple batch flotation tests on real ores to advanced spectroscopic and calorimetric studies of the physicochemical properties of mineral surfaces. The proposed research should enhance the industry's ability to treat mineral resources by flotation from process waters of complex chemistries and should also provide guidelines for recycling of high-salinity waste waters. Froth flotation is the most important fine particle processing method. Considering the fact that the mining industry is gradually moving towards recovering unconventional mineral resources (e.g., seafloor deposits), the results of this work will become a valuable source of data about the behavior of such technologically-challenging systems.

矿物加工的物理化学方法，例如泡沫浮选，依赖于在矿物-溶液界面处发生的几种相关界面现象。已知聚合物和表面活性剂吸附、表面充电、颗粒-气泡附着和颗粒的聚集/分散是pH和离子强度的函数。虽然传统上使用术语离子强度来表示工艺用水中的总电解质浓度，但它没有考虑一些特定的效应，通常称为溶致效应，这些效应是由离子尺寸的差异引起的。就其对周围水结构的影响而言，所有离子大致可分为两组：亲液剂（水结构形成离子）和离液剂（水结构破坏离子）。直到最近，离子尺寸效应对界面水结构和相关界面现象的潜在影响才得到充分认识，但它们在矿物加工应用中的意义从未得到系统研究。该研究的主要长期目标是确定溶致效应在基本界面现象中的作用，并演示如何控制或操纵此类效应以改善泡沫浮选工艺的性能。实验计划将包括广泛的技术和方法，从真实的矿石的简单批量浮选试验到矿物表面物理化学性质的高级光谱和量热研究。拟议的研究应能提高工业界通过从复杂化学品的工艺沃茨中浮选来处理矿物资源的能力，还应能为高盐度废水沃茨的再循环提供指导方针。泡沫浮选是最重要的细粒级选矿方法。考虑到采矿业正逐步走向回收非常规矿物资源（例如，海底沉积物），这项工作的结果将成为有关此类技术挑战性系统行为的宝贵数据来源。