Coke-oven gas (COG), a byproduct of the coking process, has a relatively large fraction of hydrogen (H2). However, most COG is combusted away directly, resulting in serious waste of resources. Taking advantage of a separation gas mixture containing H2, we used a hydrate separation method in this work to recover H2 from COG. The formation conditions of COG hydrate were measured in 6 mol % tetrahydrofuran (THF) solution, which could significantly reduce COG hydrate formation pressures and make it possible to realize the industrial application of the separation technology. On this basis, the separation experiments were conducted in THF solution and THF-sodium dodecyl sulfate (SDS) solution, respectively. The experimental results of two-stage separation of COG via hydrate formation were obtained, and the effects of SDS on the reaction velocity were investigated as well. The results show that after one-stage separation, the content of H2 in residual gas can be increased from 48.41 mol % to about 65 mol %, and the recovery of H2 ranges from 81% to 96%. After two-stage separation, the content of H2 in residual gas ranges from 76 mol % to 84 mol %, and the recovery of H2 is between 72% and 91%. With the presence of SDS, the hydration reaction velocity is sped up to some extent, and the induction time and reaction time of hydrate formation are greatly shortened.