(97h) Efficient Coacervate Extraction of Cationic Industrial Dye from Wastewater

Effluent wastewater containing dyes from textile, paint, and various other industries have long posed environmental issues. Functional nanomaterials offer new opportunities to treat these effluent wastes in an unprecedentedly high efficient and facile fashion due to their large surface area-to-volume ratio. In this work, we explore a new mechanically stable hybrid nanomaterial based on the complexation of zwitterionic polyampholyte with anionic polyoxometalate (POM) nanocluster to demonstrate efficient coacervate extraction of cationic dye, methylene blue (MB) as a model waste from its salted aqueous solution. MB wastewater samples were prepared at a concentration of 0.2 g/L and were used to subject the hybrid complexes to multiple rounds of extraction to determine the upper limit of adsorption of the material. Efficiency of coacervated complexes at varied POM concentrations, varied molar ratios of polyampholyte, and different salt concentrations were measured using a UV-vis spectrophotometer. Our polyionic complexes exhibited ~99% removal efficiency for all initial MB wastewater samples with measured adsorption capacity as high as 415 mg/g, indicating extremely high efficiency. Our study also suggested that coacervate extraction could be a facile and robust method for ionic selective wastewater treatment with parameters such as temperature and pH showing no influence on removal efficiency. With the simple and straightforward coavervate complexation in solution, coacervate nanomaterials advantageously possess dual processing options in separation industry through either membrane fabrication or use directly in mixer-settlers.