Improved monazite flotation through combined use of oleic acid and alkyl hydroxamate: A surface chemistry approach

Monazite, a valuable source of rare earth elements, is typically found in complex natural ore deposits, where its separation from gangue minerals such as chlorite is essential for effective mineral beneficiation. Traditional flotation techniques using single collectors often face challenges in selectively recovering monazite from such ores. Here, we show that combining two flotation collectors enhances the selectivity for monazite, improving both recovery and concentrate grade from low-grade ore samples. Flotation experiments were conducted at room temperature, which, while industrial processes frequently use higher temperatures, offers a more energy-efficient and economically viable approach, maintaining practical relevance to typical operations. Through detailed surface chemistry analysis of the flotation products, we demonstrate that this combined approach promotes higher adsorption of flotation reagents on monazite grains, while effectively reducing the recovery of undesirable gangue minerals. This method offers significant improvements over traditional flotation methods, providing a more efficient solution for processing complex rare earth element ores. These findings advance our understanding of flotation chemistry in natural ore systems and suggest broader applications for improving mineral separation in deposits with complex mineralogy.