Polymeric membranes are extensively used for gas separations but their performance is limited by the upper bound trade‐off discovered by Robeson in 1991. Among the attractive modifications available to increase the performance of polymeric membranes, polymer blending is a unique technique because it offers a time‐ and cost‐effective method of tuning the properties of membranes. A variety of polymer blends has been explored in recent years. The application of polymer blends in gas separation membranes is described by critically analyzing the performance of polymer blend membranes. Polymer blend membranes of different polymer pairs are reviewed and evaluated in terms of phase behavior, permeability, and selectivity.

The mixed-matrix membrane (MMM) is a new membrane material for gas separation and plays a vital role for the advancement of current membrane-based separation technology. Blending between inorganic fillers like carbon molecular sieves, zeolite, metal oxides, silica and silica nanoparticles, carbon nanotubes, zeolitic imidazolate framework, metal organic framework, and glassy and rubbery polymers etc. is possible. Due to mechanical, thermal, and chemical stability, these membranes achieve high permeability and selectivity as compared to pure polymeric materials. Despite of these advantages, the MMM performances are still below industrial expectations because of membrane defects and related processing problems as well as the nonuniform dispersion of fillers in MMMs. Material selection for organic and inorganic phases, preparation techniques, material advancements, and performance of MMMs are discussed. Issues and challenges faced during MMM synthesis as well as problem solutions are highlighted.

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 (Fe 3 O 4) 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 (Fe 3 O 4) 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 (Fe 2 O 3) 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.

AbstractThe 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 CO

Polyethersulfone (PES) as a polymer along with carbon molecular sieves (CMS) as an inorganic filler and di-ethanolamine (DEA) as the third component were used to fabricate amine mixed matrix membranes (A3Ms).