Preparation and Gas Separation Performance of Polysulfone Mixed Matrix Membrane

Abstract

As an economical, environmentally friendly, and highly efficient separation technology, membrane separation is a popular research topic in the field of separation. Organic polymer materials have attracted considerable attention in membrane separation because of their controllable preparation processes, simple modification method, and high toughness. Taking polysulfone (PSF) as the substrate of gas separation membrane, we prepared the mixed matrix membrane jointly by using the solution casting method and by adding graphene oxide (GO) and carbon nanotubes (CNTs). On this basis, the permeability of the membrane for CO₂ and N₂ and the permeability coefficient of the mixed gas were studied. With the addition of CNTs and GO, the permeability of gas was significantly improved. At 0.2MPa, permeability of CO₂ increased from 553 Barrer to 975 Barrer, and permeability of N₂ increased from 536 Barrer to 745 Barrer. The max ideal separation coefficient of CO₂ and N₂ is 1.94 at 0.1MPa. Increasing of the content of carbon nanotubes can significantly improve the permeability coefficient of CO₂, while the change of inlet side pressure has a great impact on the permeability coefficient of N₂. At 0.1MPa, when the ratio of CNTs to GO was 5:1, the ideal permeability coefficient of CO₂/N₂ was 1.94, whereas the ideal permeability coefficient of PSF membrane was 1.46. The above results of PSF/GO/CNT mixed matrix membrane lay a theoretical foundation for industrial application.