Effect of different addition orders of petrochemical by-product-based mixed collectors on coal flotation

An effective collector is crucial for enhancing coal flotation efficiency. The effect of a mixed collector based on petrochemical by-products on coal flotation was investigated. The investigation included various addition orders and was conducted using flotation tests, particle size distribution analysis, GC-MS, FTIR and contact angle measurements. The Mixed addition order exhibited superior performance in flotation compared to the K+Y and Y+K orders at all tested dosages. Particle size distribution analyses revealed that the mixed collector offered better dispersion in water than individual the Y-oil and K-oil, with droplet sizes below 100 µm. FTIR and contact angle measurements indicated that coal treated with the Mixed addition order demonstrated optimal reagent adsorption and the highest level of surface hydrophobicity. Aromatic compounds in the collector interacted with the hydrophobic areas of the coal surface, while partially covering some of the hydrophilic regions between these hydrophobic sites. Conversely, heteropolar components engaged with the hydrophilic regions on the coal surface to enhance adsorption. Despite these improvements, some hydrophilic sites remained after treatments with the Y+K and K+Y orders, which continued to affect the coal flotation properties.