Experimental Study on Breakthrough Separation for Hydrogen Recovery from Coke Oven Gas Using ZIF-8 Slurry

A large amount of COG (coke oven gas) is produced from coking plants every year, which contains 55-60% H-2. In this work, the breakthrough separation of H-2 from COG with ZIF-8/ethylene glycol-water slurry was studied. Following the investigation of the (ab-ad)sorption isotherms of the single component gas CH4 and H-2, the main components of coke oven gas, in different slurries and their corresponding viscosities, and the influence of the operating conditions on the dynamic performance of CH4/H-2 separation in slurry were studied in a bubble column. Low temperature, inlet flow rate, high pressure, and solid content can extend the breakthrough time, where the longest breakthrough time interval between H-2 and CH4 can be as long as 70 min, meaning the high purity of H-2 product could be obtained easily. All the results of this work prove the feasibility of the slurry method to separate CH4/H-2 mixture and provide a theoretical basis for practical industrial applications.