New engineered biopolymers and synthetic polymers

About Program 3

Application of polymers as collectors in minerals processing is relatively new. Polymers have traditionally been used in flotation to suppress recovery of certain minerals, while high molecular weight polyacrylamides have been the foundation of flocculation in solid-liquid separation. New approaches to the synthesis of more effective and cheaper polymers are now available for exploitation in minerals processing. These could lead to better concentrate grades, higher mineral recovery and new polymers to achieve improved water recovery.

Program 3 will use the knowledge of how polymers interact with minerals, coupled with novel synthesis concepts from chemistry and biochemistry, to design mineral processing chemicals that give unrivaled performance in recovering valuable minerals, whilst also allowing the recovery of as much water as possible. Polymers have been used extensively to stop unwanted minerals from being recovered and to manage the treatment of waste minerals. They have seldom been used for targeted recovery of the valuable minerals, and their use in water recovery from waste minerals has not seen a major advance in many years. Clever polymer chemistry, for both synthetic polymers and for biopolymers, will enable the production of the next generation of mineral processing chemicals that will perform better and be produced more cheaply than currently used chemicals in mining.

Program 3 consists of two sub-programs

The first sub-program will address major challenges in: i) improving selectivity of valuable mineral recovery; and ii) producing easily dewatered waste mineral streams through aggregation of fines. For both biopolymers and synthetic polymers, the work will focus on developing macromolecules for targeted adsorption, i.e. the inclusion of specific chemistries that will ensure the polymer sticks to the intended mineral, and not to others in the mixture. Coupled with this targeting will be an inherent design characteristic that will allow the polymer-coated mineral to present itself as hydrophobic as possible, ensuring optimum recovery – of minerals in the first instance, and of water in subsequent processing steps. 

The second sub-program will take the novel chemistry of the polymers designed in the first sub-program, and they will be further exploited to develop stimuli responsive molecules for coating minerals. Stimuli, such as a change in pH, salt concentration, or temperature, or exposure to light, can result in altered surface properties for polymer-coated minerals, and therefore lead to altered process outcomes. Stimulus responsive polymers are employed routinely in areas such as biomaterials science, to control surface interactions of relevance for physiological processes. Minerals processing has the potential to benefit greatly from adopting the paradigm of stimulus responsive surfaces.