Abstract:
How to efficiently treat oil-polluted water has been a common concern of researchers all over the world. Polyvinyl alcohol (PVA) hydrogel as a soft material with high water content and three-dimensional hydrophilic network had attracted wide attention in the field of oil-water separation. However, like most hydrogel with super wettability, PVA hydrogel oil-water separation materials have poor mechanical properties and poor chemical stability. Based on this, 2D Ni-Fe metal-organic frame material (MOF)-diatomite (Dia) nanomaterials and their PVA compo-site hydrogels were prepared by microwave method. After immersion in 2D Ni-Fe MOF-Dia/PVA solution, the 2D Ni-Fe MOF-Dia/PVA stainless steel mesh was obtained, showing super hydrophilic and super hydrophobic properties. The chemical composition and surface morphology of 2D Ni-Fe MOF-Dia and its composite hydrogels were analyzed by SEM and XPS. The mechanical properties of 2D Ni-Fe MOF-Dia/PVA composite hydrogel and the separation efficiency and water flux of 2D Ni-Fe MOF-Dia/PVA composite hydrogel stainless steel screen were studied. The salt resistance, acid and alkali resistance of oil-water separation were tested. The results show that 2D Ni-Fe MOF-Dia/PVA composite hydrogel has excellent mechanical properties, tensile strength and compressive strength reached 1.49 MPa and 0.58 MPa respectively, and exhibited super hydrophilic underwater super thinning oil. The efficiency and flux of 2D Ni-Fe MOF-Dia/PVA stainless steel screen are 99.2% and 742.7 L·m
−2·h
−1 respectively. It maintains excellent separation efficiency and flux in acidic, alkaline and salt environments, and still maintains stable separation efficiency and flux after 5 cycles.