Current projects | Crystallization and Precipitation Research Unit

	Systematic comparison of the effectiveness of water treatment processes This project is based on the hypothesis that existing processes for treatment of wastewater streams are not necessarily the most effective, partly because both the range of contaminants and treatment methods is very broad. This project is focussed on testing this hypothesis by modelling (on a single simulation platform) a wide range of proven water treatment technologies, combining these into both existing and new processes, and performing multi-criteria evaluations and comparisons of these processes (also using the available tools on the simulation platform). more >
	Antisolvent Crystallization of Rare Earth Sulphates Using a Fluidised Bed Reactor The global supply vulnerability of rare earth elements (REE) is driving the need for innovative technologies to recover these vital resources. These metals are used for advanced improvements in products such as batteries, magnets and catalysts. Currently, hydrometallurgical processes lack selective and efficient REE recovery. This work focuses on the development of an antisolvent crystallization process for the recovery of REE sulphates from sulphuric acid leach liquors. more >
	Eutectic Freeze Crystallization Operational Variables effects on Products Yield and Purity Eutectic Freeze Crystallization (EFC) is a novel and cost-effective separation technique for industrial brines. This process operates by simultaneous crystallization of ice and salt under sub-eutectic conditions. Scale-up of this process has not been successfully achieved due to challenges that still exist in the process. This study is aimed at understanding the effect operational conditions to elucidate their contribution to the products yield and purity. more >
	Investigating the effect of mixing on crystal growth during antisolvent crystallization of REE from NiMH battery leach liquors In this study, it was proposed to design an antisolvent crystallization process to recover REEs from NiMH batteries synthetic leach liquors using a confined impinging jet crystallizer. The study will primarily focus on the effect of mixing/hydrodynamics on the crystal size and crystal size distribution with neodymium sulphate as a model system. more >
	Innovative Processes For Rare Earth Element Recovery From Waste Water The project aims to firstly identify wastewaters or acid mine/rock drainage streams in South Africa containing REEs. Finally, an innovative extraction method, which is economical and feasible, will be investigated for the recovery of these REEs. Finally, an innovative extraction method, which is economical and feasible, will be investigated for the recovery of these REEs. more >
	Investigating the Feasibility of Using a Novel Composite Material as a Material of Construction in the EFC Application of Industrial Brines It has been demonstrated that novel polymer composite materials (low surface energy and smooth surface) can resist ice scaling in Eutectic Freeze Crystallization (EFC). However, these new composite materials have not been used for EFC applications of typical South African industrial brines. Therefore, the purpose of this study is to investigate the feasibility of using a novel composite material (PP-GR) to delay the formation of ice scaling in South African industrial brines. more >
	MnCO₃ Precipitation from Industrial MnSO₄ Pregnant Leach Solutions Manganese carbonate (MnCO₃) is widely used in the production of ferromanganese and silicomanganese alloys, fertilizers, and wastewater treatment to eliminate heavy metal contaminants. Recent research has highlighted the potential of utilizing MnCO₃ as a cathode material for rechargeable lithium-ion batteries due to its high theoretical capacity and low cost compared to other materials. more >