Preparation of an emulsion membrane utilizing ionic liquids for the efficient removal of cationic dye: extraction and breakage study

This study focuses on developing an ionic liquid-based emulsion membrane to remove a cationic dye from an aqueous solution. The researchers employed an emulsion liquid membrane (ELM) characterization method based on droplet sizes and membrane breakage rate to evaluate the impact of various parameters on dye extraction. The parameters investigated include surfactant concentration, carrier concentration, treat ratio, phase ratio, internal phase concentration, agitation speed, agitation time, and mixing speed. The ELM used in this study is a thick milky solution composed of a carrier (aliquat 336), diluent (kerosene), surfactant (SPAN 80), and stripping agent (NaOH). The optimum conditions for dye extraction were determined based on the experimental results. Under these conditions, a maximum dye extraction efficiency of 99.7% is achieved. The optimum conditions included a surfactant concentration of 4% ( v/v ) SPAN 80, a carrier concentration of 2% ( v/v ) aliquat 336, an agitation speed and time of 16,000 rpm and 10 min, respectively, NaOH concentration of 0.5 M, a treat ratio of 1:2, a phase ratio of 1:2, and a mixing speed of 350 rpm. In addition to the dye extraction, the study also examined the effect of the emulsion liquid membrane on the removal of chemical oxygen demand. However, the given information does not mention specific results or conclusions regarding this aspect. The study successfully developed an ionic liquid-based emulsion membrane technique for removing a cationic dye from an aqueous solution. The optimized conditions yielded high dye extraction efficiency, demonstrating the potential of the proposed method for dye removal applications. Graphical abstract