【摘要】 采用邻二氮菲比色法研究了Fe3+与不同浓度的胡敏酸(HA)和富里酸(FA)的氧化还原反应动力学特征.结果表明,采用常用动力学方程对反应过程进行拟合,二级反应方程比较满意.在相同腐殖酸浓度下,随着Fe3+初始浓度的增加,腐殖酸还原Fe3+的速度常数k2降低,而还原反应半衰期t1/2增大;HA还原Fe3+的速率常数k2大于FA,半衰期小于FA.HA对Fe3+的还原能力较FA高,氧化还原容量亦比后者大.更多还原

【Abstract】 humic acid (HA) and fulvic acid (FA) were extracted evergreen broad leaved forest surface layer soil of Jingyun Mountain in China. The dynamics characters of oxidation-reduction of Fe3+ with humic acid (HA) and fulvic acid (FA) of different concentrations were studied adopting bathophenanthroline colorimetry technique. Two rank reaction equations were satisfied relatively adopting dynamic equation in common use to combine reaction process. The velocity constants of HA on reducing Fe3+ k2 decreased with increase of initial concentration of Fe3+; while the half time t1/2 increased under same concentrations of HA. The k2 of HA was greater than that of FA, but the half time of the former were obviously less than that of the latter. The reduction ability of HA on Fe3+ higher than that of FA; and oxidation-reduction capacity was also larger than the latter.更多还原