Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, Ontario N2L3G1, Canada.
Environ Sci Technol. 2010 Apr 15;44(8):3098-104. doi: 10.1021/es903480k.
Batch and stop-flow column experiments were performed to estimate persulfate decomposition kinetic parameters in the presence of seven well-characterized aquifer materials. Push-pull tests were conducted in a sandy aquifer to represent persulfate decomposition under in situ conditions. The decomposition of persulfate followed a first-order rate law for all aquifer materials investigated. Reaction rate coefficients (k(obs)) increased by an order of magnitude when persulfate concentration was reduced from 20 g/L to 1 g/L, due to ionic strength effects. The column experiments yielded higher k(obs) than batch experiments due to the lower oxidant to solids mass ratio. The kinetic model developed from the batch test data was able to reproduce the observed persulfate temporal profiles from the push-pull tests. The estimated k(obs) indicate that unactivated persulfate is a persistent oxidant for the range of aquifer materials explored with half-lives ranging from 2 to 600 d.
进行了批量和停流柱实验，以估计在七种特征明确的含水层材料存在的情况下过硫酸盐的分解动力学参数。在砂质含水层中进行了推-拉测试，以代表原位条件下过硫酸盐的分解。过硫酸盐的分解遵循所有研究的含水层材料的一级反应定律。由于离子强度的影响，当过硫酸盐浓度从 20 g/L 降低到 1 g/L 时，反应速率系数（k(obs)）增加了一个数量级。由于氧化剂与固体的质量比较低，柱实验产生的 k(obs)高于批量实验。从批量测试数据开发的动力学模型能够再现推-拉测试中观察到的过硫酸盐时间分布。估计的 k(obs)表明，未激活的过硫酸盐是探索的含水层材料范围内的持久性氧化剂，半衰期范围为 2 至 600 天。
