Deng Jian-cai, Jiang Xin, Wang Fang, Lu Xin, Yu Gui-fen, Yan Dong-yun, Bian Yong-rong
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Huan Jing Ke Xue. 2005 Nov;26(6):137-42.
Kinetic batch experiments are carried out in order to investigate the effects of a wide range of atrazine initial concentrations and consecutive desorption time on the desorption characteristics of atrazine from fluvo-aquic soil. The results reveal that, atrazine concentrations in soil solution gradually decreased with desorption time increasing, whose relationship can be expressed with empirically exponential functions. After consecutive five steps (or 5 days), when atrazine initial concentrations increased from 50 microg x L(-1) to 2000 microg x L(-1), the average desorption percentages were 23.1%, 30.4%, 33.0%, 36.4% and 38.5%, respectively. The relationships between the amount of atrazine adsorbed by soil colloids and corresponding atrazine concentrations in soil solutions may be described through the traditional and time-dependent desorption isotherms. The obvious discrepancies in two families of both traditional and time-dependent desorption isotherms from adsorption isotherm, which retention time last for 168 hours before commencement of desorption, were indicative of hysteresis. Two sets of Freundlich parameters derived from both desorption isotherms can quantify the hysteresis between desorption and adsorption isotherms. However, hysteresis coefficient, omega, was applicable only for the traditional desorption isotherms, H and lamda applicable for both.
开展动力学批量实验，以研究多种阿特拉津初始浓度和连续解吸时间对阿特拉津从潮土解吸特性的影响。结果表明，随着解吸时间的增加，土壤溶液中阿特拉津浓度逐渐降低，其关系可用经验指数函数表示。经过连续五步（或5天），当阿特拉津初始浓度从50μg·L⁻¹增加到2000μg·L⁻¹时，平均解吸百分比分别为23.1%、30.4%、33.0%、36.4%和38.5%。土壤胶体吸附的阿特拉津量与土壤溶液中相应阿特拉津浓度之间的关系可以通过传统的和随时间变化的解吸等温线来描述。在解吸开始前保留时间为168小时的传统和解吸时间相关的两类解吸等温线与吸附等温线存在明显差异，这表明存在滞后现象。从两类解吸等温线得出的两组弗伦德利希参数可以量化解吸等温线与吸附等温线之间的滞后现象。然而，滞后系数ω仅适用于传统解吸等温线，H和λ则适用于两者。
