(788d) Synthesis of Zeolitic Imidazolate Framework ZIF-7 and Application for CO2 and CH4 Separation

Synthesis of Zeolitic Imidazolate Framework ZIF-7 and Application
for CO₂ and CH₄ Separation

Xiaofei Wu, Mehdi Niknam, Bin Yuan, Shuguang Deng

New
Mexico State University

Chemical
Engineering Department

Las
Cruces, NM 88003

Zeolitic imidazolate framework ZIF-7 is synthesized by both conventional
hydrothermal method and microwave-assisted methods. The cubic structures of these
two ZIF-7 samples obtained in this work are confirmed by X-ray powder
diffraction results. The scanning electron microscopy (SEM) images of these two
samples reveal that they have different particle sizes. The pore textural
properties obtained by carbon dioxide adsorption at 0ºC also indicate that they
have different pore structures. Adsorption equilibrium and kinetics of CO₂
and CH₄ on these two samples are determined at various temperatures
and gas pressures up to 1 bar, which match the simulated results. The combined
equilibrium and kinetic selectivity is calculated from the adsorption isotherms
and the adsorption kinetic plots, the results show that both of these two ZIF-7
samples have a good selectivity of separating CO₂ and CH_4.

Keywords: Adsorption, CO₂/CH₄
separation, microwave-assisted synthesis, ZIF-7