Formulation design of microemulsion collector based on gemini surfactant in coal flotation. (1st June 2020)

• Record Type: Journal Article
• Authors: Zhu, Xianchang; He, Meng; Zhang, Wei; Wei, Hengbin; Lyu, Xianjun; Wang, Qingbiao; You, Xiaofang; Li, Lin
• Is Part Of: Journal of cleaner production. Volume 257(2020)
• Publication Date: 2020-06-01
• Subjects: Coal -- Microemulsion collector -- Pseudo ternary phase diagram -- Simplex lattice mixture design method -- Flotation; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2020.120496
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: The production of slime is extremely huge, which floated by the existing hydrocarbon oil collectors without favorable efficiency. To improve the efficiency of coal slime flotation, the microemulsion collector was synthesized by a gemini non-ionic surfactant (ethoxylated 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol, Surfynol® 485) as the surfactant and diesel as the oil phase. To explore the effect of the components of the on stability of microemulsion and determine the optimal composition of the microemulsion, the simplex lattice mixture design method was adopted for the first time. Furthermore, the solubilization performance of the resulting microemulsion was determined based on its pseudo ternary phase diagram, and the optimal concentrations (mass fraction) of the gemini nonionic surfactant (Surfynol® 485), n -octanol, diesel, and water corresponding to the smallest droplet size were found to be 30.97%, 30.97%, 32.37%, and 5.69%, respectively. In addition, the microemulsion was found to remain stable even after storage for long periods at different temperatures and exhibited good homogeneity even after being centrifuged at various speeds, as confirmed by visual inspection (phase separation). Stability experiments showed that the optimized microemulsion collector had a polydispersity index of less than 0.06, suggesting it exhibited good dispersibility. The results of flotation experiments showed that the microemulsion exhibited a yield as high as 69.70% for a dosage of 3 kg/t without a frother, the dosage of which is significantly less than diesel, the microemulsion had a greater collection capacity and thus can replace diesel for the flotation of coal slime. Graphical abstract: Image 1 Highlights: Pseudo ternary phase diagram performed solubilization of gemini microemulsion. Optimal composition of microemulsion is obtained by SLMD. Microemulsion is independently used without frother for coal flotation.