Pyrolytic utilization of a typical halophyte: Suaeda glauca-the excellent adsorbent raw material for bisphenol S removal

Suaeda glauca (SG), widely applied to restore salinized land, was used to prepare biochar (activated) for the adsorption of bisphenol S (BPS) from water. SG had a high cellulose content and uniform salt ion distribution. The migration pathway of salt ions in halophytes was analyzed via energy dispersive spectrometer (EDS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and X-ray diffraction (XRD). Phosphoric acid impregnation could lead to the leaching of 80.52% of salt ions from SG. The products had high specific surface area (1339 m(2)/g) and adsorption capacity for BPS (437 mg/g). Response surface methodology indicated that pH and temperature could significantly influence the adsorption capacity. Molecular dynamics and quantum chemistry were used to describe the adsorption process and mechanism. By comparing the pore size distribution and adsorption capacity of different carbons with the simulation results of molecular dynamics, it can be discovered that the effect of micropore size on pollutant adsorption is verifiable through graphite layer modeling. Meanwhile, the presence of salt ions had no significant effect on BPS adsorption capacity. The absorption mechanism might be ascribed to a large specific surface area and pi-pi bond interactions.