Abstract:Diffusion-absorption method was used to investigate the effect of humic acid (HA) on different types of mineral bound mercury, especially under light condition. The results suggested that two HA (TJ and SH) could reduce CaCO3-Hg, MnO2-Hg and Fe2O3-Hg significantly, and the trend of increasing initially then stabilizing was observed in kinetics experiment. In addition, two constants from Elovich and exponential equation were well fitted with the kinetics process, meanwhile reduction capacities of HA varied due to mineral type, indicating that the order of average reduction rate was as follows: CaCO3-Hg(0.67%)>Fe2O3-Hg(0.42%)>MnO2-Hg(0.19%). Furthermore, light could enhance the reduction of humic acid on mineral bound mercury, showing that the greatest significance in CaCO3-Hg and Fe2O3-Hg, and the average reduction rate was 0.10% higher in comparison with in darkness condition. The reduction capacities of two humic acids (SH and TJ) were different (P<0.1) significantly, and SH reduction capacity all was greater than TJ in darkness, except that TJ was greater than SH in reduction of CaCO3-Hg under light condition, however in the same light environment, the reduction of MnO2-Hg between SH and TJ was not significantly different, which maybe explained through differences of free radical groups and aromatic degree (E4/E6) resulted in various reduction capacity.
刘丽琼, 江韬, 魏世强, 张艳敏, 李雪梅. 胡敏酸对不同矿物结合汞的还原作用[J]. 中国环境科学, 2011, 31(12): 1998-2004.
LIU Li-Qiong, JIANG Tao, WEI Shi-Qiang, ZHANG Yan-Min, LI Xue-Mei. Effects of humic acids on the reduction of different mineral bound Hg. . CHINA ENVIRONMENTAL SCIENCECE, 2011, 31(12): 1998-2004.