Intramolecular Donor–Acceptor Design in Porous Organic Framework for Liquid Fuels Adsorption Desulfurization

A porous organic framework containing well-defined donor–acceptor units, named donor–acceptor porous organic framework (D–A-POF), is successfully synthesized. The localized electric field gradient at the pore surface induced by the intramolecular donor–acceptor (D–A) interactions endows D–A-POF with excellent desulfurization capabilities. D–A-POF exhibits high adsorption capacity of 3-methylthiophene (12.26 mmol g⁻¹, 392.32 mg S g⁻¹) and 1-benzothiophene (793.65 mg g⁻¹, 189.25 mg S g⁻¹) with impressive adsorption selectivity. Density functional theory calculations provide compelling evidence of the preferential selective adsorption of aromatic thiophene sulfides in D–A-POF. In fixed-bed breakthrough experiments, D–A-POF demonstrates its ability to selectively capture thiophene sulfides from model gasoline, resulting in fuel with sulfide content below 10 ppb. The high stability and high desulfurization efficiency of D–A-POF make it promising as a new porous adsorbent for ultra-depth adsorption desulfurization.