Implantation of guanidine chemical adsorption sites in hyper-crosslinked polymers for effective adsorption and conversion of H2S

Abstract

The efficient and selective separation of H2S is of critical scientific importance in the desulphurization of natural gas. In this work, we demonstrate a novel approach for incorporating guanidine chemical adsorption sites into hyper-crosslinked polymers (HCPs) for the first time. As expected, these HCPs exhibited excellent H2S adsorption capacity of up to 7.66 mmol·g−1 and high separation selectivity values of 133 for H2S/CO2 (0.15/0.85) and 977 for H2S/CH4 (0.15/0.85) at 25 °C and 1 bar. These HCPs maintained their structural stability after adsorbing H2S and successfully catalyzed the conversion of H2S to thiols with an approximate yield of 99 % under mild conditions. The results obtained from X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR), In-situ FTIR spectrometer (FTIR), and density functional theory (DFT) calculations validated that the HCPs achieved good selective trapping and catalytic conversion of H2S through chemisorption interaction and activation. This study provides valuable insights into the development of porous materials for efficient removal and conversion of H2S, while also highlights the potential of HCPs in gas separation and conversion.