[Leaves of Platanus orientalis as the carbon source for denitrification].

Leaching solution from Platanus orientalis fallen leaves was used as the carbon source for denitrification, and organic acid releasing regularity and influencing factors during the dipping process were discussed. The main organic acid was fumarate, and others were citric acid, oxalic acid and malic acid according to the analysis by HPLC. The average nitrate removal rate was 2.19 mg x h(-1), when the leaching solution was used as the carbon source during denitrification, while the rates were 2.29, 2.26 and 1.87 mg x h(-1) respectively with methanol, acetic acid and glucose as the carbon source. The rate with the leaching solution was slightly lower than those with methanol and acetic acid, but higher than that with glucose. The experimental results indicated that 7.5 mg equivalent of COD from the leaching solution of Platanus orientalis fallen leaves were met for 1 mg nitrate reduction and there was no nitrite accumulation during the denitrification.