摘要:To examine the factors affecting nitrate removal in a nanoiron-bacteria denitrification system, two pseudo-first-order expressions (Kobsi and Kobs2) were applied to determine the chemical and biological kinetics. When the pH was increased from 7 to 9, Kobsi decreased by 60.2 % and produced no significant effect on KobS2- In addition, when the dissolved oxygen level was elevated, both Kobsi (0.463-0.665 d'1) and kohs2 (0.510-0.767 d'1) kept in a smaller extent. Furthermore,Kobsi and Kobs2 at 5 °C were, respectively, 81.4% and 86.0% lower than their values at 30 °C. When the amount of NaHCO3 increased from 50 to 250 mg L_1,Kobsi increased to about 172 %, whereas KobS2 did not change noticeably. The phosphorus source and perchlorate concentration did not significantly affect either chemical or biological reactions. Furthermore, an increase in sulfate concentration led to a decrease in both Kobsi and fcbs2. Our results indicate that low pH value, low temperature, and the presence of interfering ions may inhibit nitrate removal in the system.