(130c) High-Capacity Methane Storage in Flexible Alkane-Linked Porous Aromatic Network Polymers
AIChE Spring Meeting and Global Congress on Process Safety
Thursday, August 20, 2020 - 11:40am to 12:00pm
Adsorbed natural gas (ANG) technology is a viable alternative to conventional liquefied or compressed natural-gas storage. Many different porous materials have been considered for adsorptive, reversible methane storage, but fall short of the US Department of Energy targets (0.5 g gâ1, 263 l lâ1). Here, we prepare a flexible porous polymer, made from benzene and 1,2-dichloroethane in kilogram batches, that has a high methane working capacity of 0.625 g gâ1 and 294 l lâ1 when cycled between 5 and 100 bar pressure. We suggest that the flexibility provides rapid desorption and thermal management, while the hydrophobicity and the nature of the covalently bonded framework allow the material to tolerate harsh conditions. The polymer also shows an adsorbate memory effect, where a less adsorptive gas (N2) follows the isotherm profile of a high-capacity adsorbate (CO2), which is attributed to the thermal expansion caused by the adsorption enthalpy. The high CH4 capacity and memory effect make flexible porous polymers promising candidates for ANG technology.