Water in Sustainable Hydrometallurgy

点击翻译按钮获取中文摘要

With increasing global demand for raw materials, the Canadian metals industry is expanding and investing in new projects around the world. Hydrometallurgy uses water-based chemistry to engineer metal recovery from natural mineral resources and inorganic wastes by employing a variety of chemical conditions within a wide range of temperatures and pressures. The present research programme shifts our research focuse from improving metal extraction efficiencies to improving water quality, recyclability and usage in this industry. Sustainable development calls for minimum process water usage, high efficiency of separations, and cleanest discharge. The proposed work builds upon previous theoretical advances backed by experimental measurements in our research group aiming at developing novel applications that find their way in the industry. Three interconnecting projects are proposed that aim at improving industrial process water purification, recycling and usage. The first is Forward Osmosis (FO) for the recovery of water from contaminated process streams. It is a spontaneous process, has low energy consumption and will be adapted from the water desalination industry. The second is Eutectic Freeze Crystallization (EFC) for the recovery of both process water and highly soluble salts, which accumulate in plant circuits creating reuse/recycle problems. This technology is particularly attractive for implementation in the cold Canadian climate. The third is the further development of our novel idea to use Molten Salt Hydrates (MSH) as lixiviants to separate and recover metals from natural or recycled resources. MSH use small amounts of water for metal extraction, and have the potential to transform the field of hydrometallurgy to that of minimum net water usage. The proposed research program will train 3 PhD and 15 undergraduate students as well as one postdoctoral fellow in sophisticated experimental techniques. This work contributes to the Canadian economy by investigating novel sustainable technology ideas in the minerals sector that renders metal producers more competitive in the global markets to satisfy the world demand for primary metals produced in an environmentally respectful and sound manner.