TY  - JOUR
AU  - Gao, Ninghan
AU  - Zhang, Ruihang
AU  - Zhao, Ziying
AU  - Cao, Pan
AU  - Liu, Muxian
AU  - Liu, Bei
AU  - Deng, Chun
AU  - Chen, Guangjin
PY  - 2026
TI  - Rigorous modelling and multi-objective optimization for hybrid absorption-adsorption separation process of CH4/C2H6 using ZIF-8/iso-hexadecane slurry
JO  - Green Chemical Engineering
SN  - 2096-9147
SP  - 447
EP  - 459
VL  - 7
IS  - 4
AB  - Efficient separation of CH4 and C2H6 remains a critical challenge in the recovery of light hydrocarbons from natural gas. So we developed a zeolite imidazolate framework-8 (ZIF-8)/iso-hexadecane slurry for CH4/C2H6 separation, and conducted solubility measurements for pure components and equilibrium separation experiments for gas mixtures. A rigorous absorption-adsorption coupled phase equilibrium model and a single equilibrium stage mathematical model were established to describe the phase equilibrium performance of gas-slurry system. The results indicated that the model exhibits high predictive accuracy for the solubility of CH4 and C2H6 in the slurry, with an average relative error of less than 3.053%. Furthermore, the whole process of absorption-adsorption-desorption was designed, and the mathematical model and multi-objective optimization framework were established. The effects of operating pressure and gas-slurry ratio on product purity, recovery ratio, and total unit energy consumption were investigated. The results showed that the C2H6 purity in the feed gas is enriched from 22 mol/mol to 94.69 mol/mol, the C2H6 recovery ratio reaches 95.21%, and the total unit energy consumption is 0.4558 kW·h·Nm−3 (feed gas). In addition, the effects of pressure, temperature, and ZIF-8 solid content on slurry separation performance were analyzed using the established equilibrium-stage model. The results showed that the introduction of ZIF-8 enhances the separation performance of the iso-hexadecane solvent for mixed gases. Compared to the pure solvent, the separation factor increased by an average of 72.5%, which theoretically proved the advantages of slurry separation process.
UR  - https://doi.org/10.1016/j.gce.2025.07.002
DO  - 10.1016/j.gce.2025.07.002