Design of Efficient, Hierarchical Porous Polymers Endowed with Tunable Structural Base Sites for Direct Catalytic Elimination of COS and H2S.

Hydrogen sulfide (H2S) is malodorous and highly toxic, and its selective removal from industrial feedstock is highly recommended for safety and environment protection. We report here a class of nitrogen-functionalized, hierarchical porous polymers (N-HPPs) synthesized from one-step alkylation-induced cross-linking without any involvement of templates. The as-engineered N-HPPs are large in BET surface area (792-1397 m2/g) and endowed with hierarchical porosity. The incorporated nitrogen species of N-HPPs act as structural base sites with properties that can be precisely controlled. By molecular simulation, the enhanced interactions between N-HPPs and H2S were verified. The synthesized N-HPPs show superb capacities for H2S adsorption (9.2 mmol/g at 0 °C, 1.0 bar) and display satisfactory IAST H2S/N2 and H2S/CH4 selectivity (88.3 and 119.6, respectively, at 0 °C). Catalyzed by the structural base sites located in the N-HPPs, the COS together with its derived H2S can be effectively eliminated under mild conditions.