Mixed matrix membranes embedded stiffer ZIF-8 for highly efficient SF6 recovery

Sulfur hexafluoride (SF 6 ) is widely utilized as an insulating gas in power systems because of its outstanding dielectric insulation and arc-quenching properties, which presents significant value and necessity for recycling from both environmental impact and economic benefit. However, conventional thermally driven methods for SF 6 recovery suffer from high energy consumption, urgently necessitating the development of alternative separation techniques that operate under ambient conditions and reduce energy consumption. Herein, a stiffer EZIF-8 is employed as fillers in mixed matrix membranes (MMMs) for efficient SF 6 recovery. EZIF-8 is synthesized under an electric field, which is mainly composed of ZIF-8_ Cm phase. The fabricated MMMs exhibit an excellent N 2 /SF 6 selectivity of 182 with N 2 permeability of 278 Barrer, showing an 18-fold improvement in selectivity compared to that of the pure polymer membranes. Importantly, for both typical insulation gas mixture (70 % N 2 /30 % SF 6 ) commonly used in gas insulated switchgear and 100 h long-term operation, the MMMs are able to maintain steady operation with a relatively high N 2 permeability and N 2 /SF 6 selectivity, demonstrating the promising potential for the efficient recovery of SF 6 especially at low concentrations.