Study on the application and mechanism of disodium laureth sulfosuccinate (DLSS) as efficient collector in the flotation separation of macerals

This study employed the biodegradable surfactant disodium laureth sulfosuccinate (DLSS) as collector to achieve efficient separation of macerals. The flotation mechanism was elucidated by integrating molecular docking, FTIR spectra measurement, atomic force microscopy (AFM) topography test, and zeta potential measurement. Flotation results indicate that DLSS preferentially promotes vitrinite flotation. When DLSS dosage was 0.20 mM, vitrinite content reached 83.70% with recovery of 69.39%. After frother dosage optimization, vitrinite content increased to 84.37% and recovery reached 78.75%. Mechanistic analysis reveals that DLSS can form stable hydrogen bonds with the -NH and -OH groups on the vitrinite surface through its polar groups, resulting in a more negative binding energy, thereby achieving selective adsorption, while its interaction with inertinite is predominantly hydrophobic. FTIR and AFM topography results further confirm stronger adsorption of DLSS on vitrinite surface, effectively covering the hydrophilic sites. Zeta potential measurements show that DLSS adsorption on vitrinite stabilizes at 0.20 mM, whereas adsorption on inertinite continues, resulting in the maximum adsorption difference and optimal flotation enrichment. This work reports the first application of sulfosuccinate-based surfactant for maceral separation. Its biodegradable and efficient nature makes DLSS a promising collector, holding significant potential for achieving efficient and green separation of macerals.