Preparation of mixed matrix membranes containing nickel iron oxide nanoparticles for separation of carbon dioxide, nitrogen and methane

 In recent years, researchers have proposed various methods for gas separation because of rising greenhouse gases in the atmosphere and causing enormous environmental problems. One of the newest and emerging methods is membrane gas separation. In the last decade, mixed matrix membranes (MMMs) have received much attention due to their ability to successful separation of polar gases from mixtures.

In this study, a novel two-component mixed matrix membrane was prepared by incorporating the nickel zinc iron oxide nanoparticles into the Pebox polymer matrix. This is owing to combination the unique features of Pebax copolymer such as high mechanical strength and gas permeability, with nanoparticle properties as considerable permeability and selectivity, and appropriate mechanical and thermal stability. The gas permeability test was performed for pristine membrane and MMMs at 35 °C and pressure range from 2 to 10 bar. Fabricated membranes were also evaluated by FESEM, FTIR-ATR, DSC and XRD tests

Results demonstrated that in the case of the optimum membrane with 1 wt.% of filler loading and at 10 bar, the CO2 permeability was increased about 128% and reached to 278 Barrer, compared to pristine membrane. However, the CO2/CH4 and CO2/N2 selectivities were improved by 175 and 183 percent, respectively. This superior results was due to the presence of iron, nickel, and zinc atoms in the filler structure, which resulted in a better interaction with CO2. On the other hand, the presence of CO2-friendly segments in the Pebax structure caused much higher CO2 permeability in comparison with other light gases.