Synthesis of chiral mesoporous silica nanoparticles for the adsorptive removal of the chiral insecticide sulfoxaflor from water

Mesoporous materials have garnered significant interest because of their porous structure, large surface area and ease of surface functionalization to incorporate the functional groups of choice. Herein, chiral mesoporous silica nanoparticles (CMSNPs) were prepared using quaternary amino silane as the template, tetramethyl orthosilicate as the silica source and proline and cellulose as chiral selector. The developed CMSNPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction analysis, BET surface area analysis and BJH pore size/volume analysis. It was observed that the CMSNPs have high specific surface area and narrow particle size and pore size distribution. These CMSNPs were used as adsorbents for separation of the chiral insecticide sulfoxaflor. The effects of various parameters that affect adsorption, such as initial concentration of the analyte, adsorbent dose, time and pH, were evaluated, and the optimum values were determined. At optimum conditions, the removal efficiency and adsorption capacity were 98.5% and 435.45 mg g^-1, respectively. Further, adsorption isothermal study was carried out using Freundlich and Langmuir models. Results showed that mesoporous silica nanoparticles functionalized with amide-bonded cellulose are promising and cost-effective adsorbents for the removal of chiral pesticides from water and wastewater.