| Popis: |
Glyphosate is a widespread herbicide, and it is an important environmental pollutant that could have some adverse effects on human health. Therefore, remediation and reclamation of contaminated streams and aqueous environments polluted by glyphosate is currently a worldwide priority. Here we show that the heterogeneous nZVI-Fenton process (nZVI + H2O2; nZVI = nanoscale Zero Valent Iron) can achieve effective removal of glyphosate, under different operational conditions. Removal of glyphosate by excess ZVI, without H2O2, also takes place, but the use of ZVI alone to remove glyphosate from water matrices would be very costly. Glyphosate removal by nZVI-Fenton was thoroughly investigated in the pH range 3–6, with different H2O2 concentrations and nZVI loadings. We observed significant removal of glyphosate at pH 3 and 4; however, due to loss in efficiency of Fenton systems with increasing pH, glyphosate removal was no longer effective at pH 5 or 6. Glyphosate removal also occurred at pH 3 and 4 in a real-world water matrix (tap water), despite the occurrence of several potentially interfering inorganic ions. Considering that the operational conditions, used here to remove glyphosate, have already been shown to effectively induce degradation of other emerging contaminants, nZVI-Fenton looks like a promising tool to eliminate glyphosate, together with other biorecalcitrant contaminants, from environmental aqueous matrices. |
