Well-dispersed NH2-MIL-125(Ti)/poly(vinylidene fluoride) blending membranes for removal of dyes and silver ions

Creating innovative materials to extract silver ions and dye molecules from aqueous solutions is very important. The NH2-MIL-125(Ti) was integrated with a polyvinylidene fluoride (PVDF) matrix to fabricate a novel NH2-MIL-125(Ti)-based mixed matrix membranes (MMMs) to remove silver ions, Rhodamine B and Congo red. Firstly, the NH2-MIL-125(Ti) was prepared, and its structure and morphology were characterized using an X-Ray Diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), and Scanning Electron Microscope (SEM) and then, combined the dried NH2-MIL-125(Ti) with PVDF to manufacture MMMs. To create well-distributed MMMs with a substantial loading capacity, the undried NH2-MIL-125(Ti), which had been stored directly in Dimethylformamide (DMF), was used as the filler. Subsequently, a series of characterizations were conducted on the MMMs. The results revealed that adding NH2-MIL-125(Ti) significantly improved the capability of MMMs, especially MMMs modified with undried filler. Specifically, the MU10 (with a filler ratio of 10 wt%) membrane, fabricated with undried NH2-MIL-125(Ti), exhibited a high water permeability of 693.9 L m−2 h−1, and rejection rates for Congo Red (98 %), Ag(Ⅰ) (58 %), and Rhodamine B (42 %). Additionally, adsorption experiments were conducted on MU10, indicating that the uptake capacity for Ag(Ⅰ), Rhodamine B and Congo Red were 88.0, 101.2, and 261.6 μg cm−2, respectively. This study utilizes well-dispersed fillers to prepare MMMs to achieve efficient removal of Ag(I) and Congo red.