Avaliação da morfologia de novos materiais sorventes baseados em sílica modificada com Ti e PMODS para extração em fase sólida (SPE) por microscopia eletrônica de varredura (MEV)

Abstract

Faced with the commercialization potential of new sorbent materials for solid phase extraction (SPE). Some preparation conditions of metallized and polymer-coated silicas were investigated, using Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy. The SEM analyzes were carried out so that the materials were deposited on carbon tape supported on suitable metallic supports and submitted to analysis in the optical scanning microscope FEI Inspect, using a voltage of 5 keV under different magnitudes, via interaction with the National Nanotechnology Laboratory (LNNano) of the National Center for Research in Energy and Materials (CNPEM) (Campinas-SP). The results of the SEM technique showed a particle with an irregular shape not defined, but a similar shape between the particles, the visual size analysis and the histogram analysis showed that the average was around 100 µm to 120 µm, where the level of coating was shown to be greater in the sample prepared at 120 °C for 16 hours because it had a larger particle diameter, in addition to the titanium content of 1.9%. The evaluation by SEM and SEM-EDS allowed to understand the morphology of the sorbent materials, evaluating the shapes and sizes of the particle, allowing to evaluate the homogeneity and amount of Ti (through the SEM-EDS technique) incorporated to the support and the effectiveness of immobilization of the PMODS and finally allowed the physical-chemical characterization of the sorbent materials based on titanized silica and PMODS (poly(methyloctadecylsiloxane)). The phase (Si-Ti (PMODS)) immobilized at 120 °C for 16 hours in this condition was indicated as the best coating condition, the PMODS layer appearing as a thin homogeneous layer without lumps.