In-situ precipitation method is widely used and reported in the literature for the synthesis of iron oxide nanoparticles based on their applications in many fields. However, the rate of reaction and rate constant for the production of Magnetite Phase of iron oxide did not study in depth. Reaction rates are required to design a scale-up of the process. In this study, Magnetite phase of iron oxide nanoparticles (Fe₃O₄) are synthesized by the in-situ precipitation method, and the overall reaction rate is evaluated based on the concentration of Magnetite produced during the process. Further, X-ray diffraction, energy-dispersive X-ray spectroscopy and Raman spectroscopy are used to confirm the presence of a higher proportion of magnetite (Fe₃O₄) in the final product, which is responsible for more top magnetic properties 74.615 emu. Changes in morphology of these nanoparticles at different intervals of the reaction are reported by transmission electron microscope. The results showed that spherical nanoparticles synthesized at different intervals of the reaction have a very narrow range of particle size, i.e. 9–15 nm. Detailed analysis reveals the presence of a higher share of maghemite (Fe₂O₃) at the start of the reaction. However, maghemite eventually is converted to magnetite by the end of the reaction, thereby enhancing the magnetic strength of the nanoparticles.

The development of mixed matrix membrane (MMM) in gas separation process has drawn great attention due to its promising properties. MMM consists of a polymer as the matrix phase, whereas the inorganic filler serves as the dispersed phase. However, poor contact between these two phases often results in unselective gas flow and becomes one of the major issues in the MMM development. Currently, various modification techniques of the inorganic filler to improve the compatibility between the polymers and the particles have been reported. Because of this modification, the CO₂ separation from natural gas is expected to enhance. This review provides a better understanding about the modification of inorganic filler. Mechanisms and factors affecting the modification of filler such as the effect of solvent polarity, the effect of water content in solvent, and the effect of drying condition are discussed. The details of the current progress in the MMM involving the silane-modified fillers are also summarized.