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In this study, hydrogen was recovered and purified by using a membrane contactor unit from CO₂-rich gas without the use of any basic chemicals such as amines. The membrane operational parameters were adjusted to achieve high CO₂ removal and H₂ recovery. The effects of gas flow rate, pressure, gas composition (CO₂/H₂ ratio), pressure difference between liquid and gas, and gas/liquid ratio on CO₂ removal and H₂ recovery were investigated. Depending on the gas flow rate, the contact time between gas and liquid could be controlled, changing the absorption amounts of CO₂ and H₂. Regarding gas composition, an increase in the CO₂/H₂ ratio from 0.25 to 1 boosted H₂ recovery. Furthermore, increasing the CO₂/H₂ ratio above 1 (from 1 to 3) generally reduced H₂ recovery from 98.7% to 83%. Additionally, supplementation with the optimal amount of additive enhanced CO₂ removal and H₂ recovery. Thus, using a membrane contactor system results in high CO₂ removal (82.7–93.5%) and H₂ recovery (91.5–98.7%). Moreover, H₂ production and separation can be performed in one system, implying that CO₂ removal can be performed more efficiently by the membrane contactor. This study offers a new and promising route for producing high-purity H₂ while removing CO₂.