The Preparation and Performance of SPE Packing of Bonded Ligand on the Surface of Nanometer Titanium Dioxide

At present, the solid phase extraction packing of organic ligand/nano inorganic composite material is used to separate and enrich metal ions, which has become a hot research topic in analytical chemistry. A novel nano-TiO₂/TSC solid-phase extraction packing was prepared by grafting thiosemicarbazone containing N, S coordination atoms onto the surface of nano-TiO₂ by condensation reaction and is described in this paper. The structures and the property of synthesized composite were characterized and analyzed by Infrared Spectroscopy, X-ray Diffraction Scanning, X-ray Photoelectron Spectroscopy, and Electron Microscopy. The composition and size distribution of the packing particle were more uniform (the particle size is 200-300 nm) and more stable than the solid phase extraction packing made by physical blending technology. The saturation adsorption capacities of Sb³⁺, Cd²⁺ and Ba²⁺ on the solid phase extraction column prepared by this method at 30℃ were 13.9 mg/g, 12.9 mg/g, and 11.2 mg/g, respectively. The recoveries of three metal ions were 97.94%, 95.65% and 94.04%, respectively under the optimal experimental conditions. The data has good reproducibility with RSD < 5.5%. Thus, the adsorption property of the new nanometer TiO₂/TSC composite solid phase extraction packing is an improvement on the styrene-methyl acrolein-thiosemicarbazide coated nano-titanium dioxide packing and nano-titanium dioxide packing. The contents of Sb³⁺, Cd²⁺ and Ba²⁺ in water samples were determined by Inductively Coupled Plasma-Mass Spectrometry coupled with the TiO₂/TSC composite solid phase extraction packing, which yields detection limits of 0.061 μg/L, 0.013 μg/L, and 0.075 μg/L for Sb³⁺, Cd²⁺ and Ba²⁺, respectively.