Novel porous carbon composites derived from a graphene-modified high-internal- phase emulsion for highly efficient separation and enrichment of triazine herbicides.

In this study, novel porous carbon composites were successfully prepared with graphene-modified high-internal-phase emulsions (HIPEs) via a simple process of polymerization followed by carbonization. The morphology of the macroporous composites was observed and the verification of structural and functional groups were verified by scanning electron microscopy (SEM), and other characterizations techniques including Fourier transform infrared (FI-IR), X-ray photoelectron spectroscopy (XPS) spectra and Raman spectroscopy. The prepared porous carbon composites were applied to farmland water for the simultaneous adsorption of triazine herbicides and the conditions of extraction and desorption were optimized. Due to the π-π interaction and hydrophobic interaction between triazine herbicides and carbon composites, the maximum adsorption capacity of simazine, prometon and prometryn were 33.4, 34.5 and 33.8 μg g, respectively. Adsorption and desorption of triazine herbicides can be achieved in 10 min, and high-speed mass transfer was observed. The calibration curves of three triazine herbicides were linear (R ≥0.9996) in the range from 25.0 to 500.0 ng mL. The LOD of three triazine herbicides by using the proposed SPE-HPLC-DAD method were 2.5-5.6 ng mL. All the results suggest that these materials may be useful for more efficient hazardous residue separations.