Advances in membrane-based helium recovery from natural gas: materials, process integration, and techno-economic perspectives

Helium is a vital resource for applications like medical imaging, semiconductor manufacturing, aerospace systems, and low-temperature research. However, economically recoverable helium reserves are limited and increasingly come from natural gas streams with very low helium concentrations. Traditional helium recovery mainly relies on cryogenic separation, which can achieve very high purity but is costly and energy-intensive, especially when the helium content is below about 0.1 mol%. In such cases, membrane-based separation has gained interest as a feasible option for bulk pre-enrichment and integration into hybrid systems with cryogenic or adsorption units, while advanced PSA concepts (including DR-PSA) are also emerging as competitive non-cryogenic routes for selected feed windows. This review offers a connected assessment of membrane-assisted helium recovery from natural gas across four practical levels: separation fundamentals, emphasizing the partial-pressure-limited nature of dilute helium recovery and the need for mixed-gas validation under realistic impurity envelopes; membrane materials, including polymeric, carbon-based, inorganic, and mixed-matrix membranes, with attention to stability, defect control, and scale-up to modules; process integration, where multi-stage membrane cascades and membrane–cryogenic or membrane–PSA hybrids are evaluated as the most effective configurations for lean feeds; and techno-economic performance and technology readiness, highlighting how feed composition, utility availability, and intermediate enrichment targets govern feasibility. Overall, the literature indicates that membranes are most advantageous as pre-enrichment steps that reduce downstream refrigeration or adsorption duty, enabling cost-effective recovery for moderate helium levels and extending viability toward leaner feeds when deployed in optimized hybrid schemes. Key challenges remain long-term stability under CO 2 /H 2 S/water/heavy hydrocarbon exposure, robust module-scale manufacturing, and consistent integration of process, economic, and environmental metrics for fair cross-technology comparison.