Research Progress on the Application of Functionalized Celluloses in Mineral Flotation

Traditional fuel oil by−products and chemically synthesized flotation reagents pose significant environmental pollution risks. In contrast, cellulose−based flotation reagents are considered a promising environment friendly alternative for mineral flotation, offering advantages such as widespread availability, low cost, biodegradability, and functionality. This paper provides a comprehensive review of the types, mechanisms, applications, and development trends of cellulose−based depressants and collectors. Cellulose−based depressants, such as carboxymethyl cellulose (CMC) and hydroxyethyl cellulose, have been used to inhibit the flotation of calcium−magnesium silicate minerals, including dolomite, calcite, and serpentine. These depressants function by forming hydrogen bonds through the reaction of their −OH groups with mineral surfaces, thereby reducing the surface potential of the minerals. Furthermore, the Mg²⁺/Ca²⁺ ions on the mineral surfaces interact with the −COOH groups of the cellulose molecules, enhancing the hydrophilicity of the mineral surfaces. Cellulose−based collectors, such as amino−alkyl or silanized modified nanocellulose, enhance the hydrophobicity of the mineral surface via electrostatic interactions, thereby promoting particle−bubble adhesion and improving mineral flotation efficiency. These collectors offer the dual advantages of environmental sustainability and high performance. In the future, the integration of process innovation with structural design will be crucial to the development of low−cost and high−efficiency cellulose−based reagents. This development has significant practical implications for advancing green flotation reagents, minimizing the reliance on chemically synthesized flotation reagents, and mitigating potential environmental damage.