中文摘要：

以SiO2微粉为基底制备了终端接有SO3H基的自组装单层材料（SO3H／SiO2），研究了其吸附水中弱碱性除草剂西玛津的性能及机制。结果表明，SO3H／SiO2能有效清除水中西玛津，如0．12g SO3H／SiO2对20mL 1．4mg／L西玛津吸附3h，其吸附率达91％。吸附等温实验数据用Langmuir吸附等温式拟合效果优于Freundlich吸附等温式。吸附机制为静电相互作用，西玛津分子大部分以分子形式到达自组单层的表面，SO3H基电离的H^＋使西玛津质子化而带正电，从而与-SO3^-通过静电作用而保留在SO3H／SiO2的表面。

英文摘要：

The sulfonate on SiO2 （SO3 H/SiO2） self-assembled monolayers （SAMs） adsorbent was prepared in the lab. The dynamic adsorptive capacities and the mechanism of adsorption of herbicide simazine on the adsorbent were investigated. The high adsorptive capacity suggested the adsorbent was attractive for removing some weakly basic pesticides; for example, adding 0.12 g adsorbent to a 20 mL 1.4 mg/L simazine solution resulted in a concentration reduction of 91% in 3 h （capacity=212.30 mg/kg）. The adsorption capacity data were better fitted by the Langmuir isotherm model than the Freundlich isotherm model, consistent with the monolayer hypothesis. Strong electrostatic interactions were likely involved in the adsorption process; simazine molecules arrived at the SO3 H/SiO2 to form cations after incorporating the proton, which came from deprotonation of --SO3 H on the adsorbent surface, and were then chemically adsorbed. The adsorbed pesticide was difficult to be desorbed; only 1% of 〉330 mg/kg adsorbed was desorbed after washing for 24 h.