Natural Gas Purification Using a Porous Coordination Polymer with Water and Chemical Stability

Porous coordination polymers (PCPs),
constructed by bridging the metals or clusters and organic linkers,
can provide a functional pore environment for gas storage and separation.
But the rational design for identifying PCPs with high efficiency
and low energy cost remains a challenge. Here, we demonstrate a new
PCP, [(Cu4Cl)­(BTBA)8·(CH3)2NH2)·(H2O)12]·xGuest (PCP-33⊃guest), which shows high potential
for purification of natural gas, separation of C2H2/CO2 mixtures, and selective removal of C2H2 from C2H2/C2H4 mixtures at ambient temperature. The lower binding energy
of the framework toward these light hydrocarbons indicates the reduced
net costs for material regeneration, and meanwhile, the good water
and chemical stability of it, in particular at pH = 2 and 60 °C,
shows high potential usage under some harsh conditions. In addition,
the adsorption process and effective site for separation was unravelled
by in situ infrared spectroscopy studies.