Preparation of heteroatom-doped hyper-crosslinked polymers via waste utilization of sulfur-containing petroleum coke: A promising adsorbent for CO2 capture

To overcome the worldwide environmental crisis related to the continuous emission of CO₂, the use of porous organic polymers, which are excellent absorbents and conversion materials, to reduce CO₂ emission is of great significance. Among them, hyper-crosslinked polymers (HCPs) are porous materials with a high pore density that are synthesized using a simple one-pot method that is economical and can realized at a low temperature, hence they have good application prospects as adsorbents for CO₂. In this study, a batch of petroleum coke-based HCPs with different sulfur contents was prepared via the one-pot Friedel-Crafts alkylation reaction using inexpensive and abundant petroleum coke as raw material. Thereafter, the use of the prepared materials for CO₂ adsorption revealed that the HCPs with a high sulfur content had a larger specific surface area (825 m²/g) and showed a higher CO₂ adsorption capacity (2.1603 mmol/g at 1 bar 298 K) than its counterpart with a lower sulfur content. Thus, the presence of sulfur significantly enhanced the CO₂ adsorption performance of the material. Further, the simulation of the heat of adsorption of HCPs with and without sulfur using Material Studio also confirmed the higher CO₂ capture efficacy of HCPs with a higher sulfur content.