Conclusion
In summary, we synthesized a microporous metal-organic framework,
Ni(TMBDC)(DABCO)0.5 and investigated its separation
performance for recovery low content of
C2H6 and
C3H8 from natural gas. The
as-synthesized Ni(TMBDC)(DABCO)0.5 showed good thermal
stability, solvent stability and humid stability under RH = 100%. Due
to the strong interaction between the framework and the guest molecule,
the gate opening behavior of C3H8adsorption on the Ni(TMBDC)(DABCO)0.5 was observed and
the remarkably high capacities of 2.80 mmol/g at 1 kPa and 3.37 mmol/g
at 5 kPa were obtained. The IAST-predicted selectivity of
Ni(TMBDC)(DABCO)0.5 reached as high as 274 for
C3H8/CH4 (5:85, v/v) and
29 for C2H6/CH4 (10:85).
The breakthrough experiment revealed that simulated gas mixture of
C1/C2/C3 was well separated on the Ni(TMBDC)(DABCO)0.5material. The molecular simulation further confirmed the methylene
groups and methyl groups played a crucial role on
C3H8 and
C2H6 adsorption. This work unveils that
the Ni(TMBDC)(DABCO)0.5 with good stability and unique
pore environment is a promising material for recovering ethane and
propane from natural gas or other hydrocarbon separation. Looking ahead,
the shaping of Ni(TMBDC)(DABCO)0.5, for example, from
powder to spherical adsorbents with excellent mechanical strength, is
undergoing in our group, which is necessary before practical
applications.