Behaviour of hydrate-based technology for H2/CO2 separation in glass beads

•H2/CO2 is separated as flowing through porous media by hydrate formation.•Tetrahydrofuran and sodium dodecyl sulphate are used as additives simultaneously.•Hydrate forms firstly and dissociates lastly along the axial of the vessel.•Smaller glass beads (BZ-01) is suitable for hydrate-based H2/CO2 separation.•Porous media and temperature have remarkable impacts on gas compositions.

Hydrate-based gas separation is considered a promising technology for H2 purification and CO2 capture. To investigate the behaviour of this separation technology in a flowing system for industrial application, an orthogonal experiment was conducted to explore the effects of glass beads, flow rate, pressure and temperature on a mobile-phase (H2/CO2) separation system in cooled porous media. The distribution of the pore solution was measured using magnetic resonance imaging (MRI) to analyse hydrate formation/dissociation. The experimental results demonstrated that solution movement scarcely occurred in BZ-01. The lowest H2 concentration was 26.1 mol% for the hydrate dissociation process, whereas the highest value was 44.8 mol%. The overall H2 concentration for hydrate dissociation decreased with an increase in pressure, and the hydrate saturation increased with pressure. Suitable parameters for gas separation were determined to be 1.0 mL min−1 and 281.0 K in this investigation. Variance analysis indicated that porous media and temperature significantly affect the H2 concentrations in the hydrate dissociation process, whereas only porous media significantly affect hydrate saturation.

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