Iron-Nickel Alloy with Starfish-like Shape and Its Unique Magnetic Properties: Effect of Reaction Volume and Metal Concentration on the Synthesized Alloy

Novel Magnetic Mixed Cellulose Acetate Matrix Membranes with Oxygen-Enrichment Potential

This work presents novel magnetic mixed cellulose-based matrix membranes that combine the advantages of a low-cost common polymer matrix, such as cellulose acetate (CA), and a low-cost magnetic filler. Moreover, the presented magnetic mixed CA matrix membranes were fabricated and used without applying an external magnetic field during either the membrane casting or the separating process. Poly(methylmethacrylate) and lithium chloride were used in order to improve the mechanical properties and porosity of the fabricated membranes. The iron-nickel magnetic alloys used were prepared through a simple chemical reduction method with unique morphologies (Fe₁₀Ni₉₀-starfish-like and Fe₂₀Ni₈₀-necklace-like). The novel magnetic mixed CA matrix membranes fabricated were characterized using different analysis techniques, including SEM, EDX, XRD, TGA, and FTIR-ATR analyses. Furthermore, the static water contact angle, membrane thickness, surface roughness, tensile strength, and membrane porosity (using ethanol and water) were determined. In addition, vibrating sample magnetometer (VSM) analysis was conducted and the oxygen transition rate (OTR) was studied. The magnetic mixed CA matrix membrane containing starfish-like Fe₁₀Ni₉₀ alloy was characterized by high coercivity (109 Oe) and an efficient 1.271 × 10^-5 cm³/(m²·s) OTR compared to the blank CA membrane with 19.8 Oe coercivity and no OTR. The effects of the polymeric matrix composition, viscosity, and compatibility with the alloys/fillers used on the structure and performance of the fabricated mixed CA matrix membranes compared to the previously used poly(ethersufone) polymeric matrix are discussed and highlighted. The novel magnetic mixed CA matrix membranes presented have good potential for use in the oxygen-enrichment process.

Novel magnetic iron-nickel/poly(ethersulfone) mixed matrix membranes for oxygen separation potential without applying an external magnetic field

This work presents novel magnetic mixed matrix poly(ethersulfone) (PES) membranes that combine the advantages of low-cost common PES polymer and low-cost iron–nickel magnetic alloys. Moreover, the presented magnetic mixed matrix PES membranes were fabricated and used without applying an external magnetic field during either the membrane casting or the separating process. The fabricated magnetic membranes were prepared using the phase inversion technique and N-methylpyrrolidone and N,N‐Dimethylformamide solvents mixture with volumetric ratio 1:9 and Lithium chloride as an additive. The used iron–nickel magnetic alloys were prepared by a simple chemical reduction method with unique morphologies (Fe₁₀Ni₉₀; starfish-like and Fe₂₀Ni₈₀; necklace-like). The fabricated membranes were characterized using Scanning Electron Microscope (SEM) and Scanning-Transmission Electron Microscope (STEM) imaging, energy dispersive X-ray (EDX), Thermogravimetric (TGA), and X-ray diffraction (XRD). Also, static water contact angle, membrane thickness, surface roughness, membrane porosity, membrane tensile strength as well as Vibrating Sample Magnetometer (VSM) analysis and oxygen transition rate (OTR) were determined. Moreover, the effect of alloy concentration and using Lithium chloride as an additive on the properties of the fabricated blank PES and magnetic mixed matrix PES membranes were studied. The presented novel magnetic mixed matrix PES membranes have high coercivity up to 106 (emu/g) with 3.61 × 10^–5 cm³/cm²·s OTR compared to non-oxygen permeable blank PES membranes. The presented novel magnetic mixed matrix PES membranes have good potential in (oxygen) gas separation.