High temperature solution chemistry in Hydrometall

Slide1 : Vlad Papangelakis Dept. of Chemical Engineering & Applied Chemistry University of Toronto CNC-IAPWS May 23, 2003 High temperature solution chemistry in Hydrometallurgy

Slide2 : High temperature (Pressure) Hydrometallurgy Solution Chemistry challenges Research needs Outline

Simulation of Laterite Acid Pressure Leaching : Simulation of Laterite Acid Pressure Leaching

High Temperature Hydrometallurgy : High Temperature Hydrometallurgy Processes between 150 - 270°C Mineral-water systems Mineral dissolution + salt precipitation Heterogeneous + multicomponent systems Saturated + supersaturated solutions High ionic strength (I = 2 - 3 M) Acid/base and redox reactions

Solution Chemistry Challenges : Solution Chemistry Challenges Insufficient speciation information Very corrosive environments (pH<1) Chemical modelling Highly non ideal behaviour Multicomponent systems (SO4 and Cl mainly) Lack of physical data (densities, viscosities) Lack of thermodynamic data Heterogeneous + multicomponent systems

Research needs – opportunities? : Research needs – opportunities? Species ID in very concentrated solutions Instrumentation for very corrosive environments (pH<1) Chemical modelling New thermodynamic data New speciation information - characterization Better solution models Better sampling techniques for saturated systems Sensor development for acid and redox