Residue and Photodegradation of Fla in the Baotou Section of the Yellow River in Freezing-thawing Period.

Water samples were collected during freezing and flowing conditions from eight sites along the Baotou section of the Yellow River. The main aims of this study were to obtain information on the fluoranthene concentrations in freezing-thawing process; to determine how fluoranthene concentrations were distributed in water; to discuss the photodegradation of fluor anthene in the water phase; to investigate the influence of light-sensitive materials (H2O2, acetone and sediment) on the photo degradation of fluoranthene in the water phase. The results indicated that fluoranthene concentrations were relatively high at sites S2 and S5, and residue levels were lower at points S4, S6 and S7. The fluoranthene light experiment was carried out under exposure to UV light with low fluoranthene concentrations, using a light conversion function in the water and ice phase, after 72 h the concentration the degradation rate reached 90%. The degradation rates of fluoranthene in water phase were lower with acetone, sediment and low concentrations of H2O2 than without, and the fluoranthene degradation was consistent with a first-order kinetics reaction, likewise, high H2O2 concentrations promoted photoconversion. [ABSTRACT FROM AUTHOR]