The synthesis of a new, hybrid mesoporous sorbent, 4-phenylenediaminepropylsilica (4-PhAP/silica xerogel) obtained by the sol-gel process is described. This material was characterized by infrared spectroscopy (IR), elemental analysis (CHN), and nitrogen adsorption-desorption isotherms. Subsequently, this material was employed for the successful pre-concentration of copper in natural water reference materials. The copper characteristic mass was 15.0 ¡ 0.2 pg. The detection limit for copper determination in natural waters employing the pre-concentration procedure was 0.2 mg l 21 . The average tube lifetime was 750 analytical firings when 20 ml of 1.5% m/v copper sorbed on 4-PhAP/silica xerogel slurry was delivered to a previously treated W-Rh treated platform of a transversely heated graphite atomizer (TGA). The pre-concentration factor obtained with 4-PhAP/silica xerogel as adsorbent for copper determination was 3.75 and the retention capacity of the sorbent was 0.52 mmol copper per gram of sorbent.

Atividades humanas aceleram o processo natural de eutrofização das águas, favorecendo a floração de algas e cianobactérias. Estes organismos emitem os compostos 2-metilisoborneol (MIB) e geosmina, que conferem gosto e odor de mofo e terra à água. A presença destes compostos se estende à água potável uma vez que os processos convencionais de tratamento são insuficientes para removê-los. Esta pesquisa foi realizada com o objetivo de avaliar alternativas de processos de tratamento para a remoção de MIB e geosmina da água. Os processos estudados foram aeração em cascata, dessorção por ar e nanofiltração. Os resultados sugerem a possibilidade de remoção quase total de MIB e geosmina da água através do sistema de nanofiltração, enquanto que os processos baseados em aeração e dessorção foram relativamente ineficientes.

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