Preparation of PVDF/TMKH-550 composite membrane and its adsorption performance for ammonia nitrogen wastewater

In order to reduce the agglomeration of tourmaline, silane coupling agent (3-aminopropyl)-triethoxysilane (KH-550) was used to modify tourmaline. Then the modified tourmaline particles were added to the polyvinylidene fluoride (PVDF) casting solution by blending, and a series of PVDF/TMKH-550 composite membranes were prepared by Nonsolvent Induce Phase Separation (NIPS). The results showed that the agglomeration of tourmaline could be reduced by modification. With the increase of TMKH-550 nanoparticles content, the removal efficiency of ammonia nitrogen wastewater increased gradually. For PVDF/TMKH-550 composite membranes, the results showed that the addition of TMKH-550 nanoparticles improved the hydrophilicity, porosity, and pore size of the membrane, and increased the permeation flux. The removal efficiency of the composite membrane on ammonia nitrogen solutions could reach 75.40%, The pH and conductivity of deionized water after membrane filtration were tested. At 0.2 MPa, it was found that both pH and conductivity increased. The above results showed that tourmaline can not only activate water bodies but also remove pollutants in water.