Biphenyl-Based Covalent Triazine Framework/Matrimid(®) Mixed-Matrix Membranes for CO(2)/CH(4) Separation

Processes, such as biogas upgrading and natural gas sweetening, make CO(2)/CH(4) separation an environmentally relevant and current topic. One way to overcome this separation issue is the application of membranes. An increase in separation efficiency can be achieved by applying mixed-matrix membranes, in which filler materials are introduced into polymer matrices. In this work, we report the covalent triazine framework CTF-biphenyl as filler material in a matrix of the glassy polyimide Matrimid(®). MMMs with 8, 16, and 24 wt% of the filler material are applied for CO(2)/CH(4) mixed-gas separation measurements. With a CTF-biphenyl loading of only 16 wt%, the CO(2) permeability is more than doubled compared to the pure polymer membrane, while maintaining the high CO(2)/CH(4) selectivity of Matrimid(®).