季铵盐阳离子表面活性剂改性活性炭对农药毒死蜱的吸附

Adsorption of Chloropyrifos with Quaternary Ammonium Cation Surfactant-Modified Activated Carbon

活性碳具有多孔结构,对农药具有强烈的吸附作用。利用十六烷基三甲基溴化胺(HTAB)、溴代十六烷基吡啶(HPB)、四丁基溴化胺(TBAB)三种季铵盐阳离子表面活性剂对活性炭进行表面改性。利用比表面积测定、元素分析以及X射线荧光光谱等对吸附剂进行了表征,研究了改性活性炭对农药毒死蜱的吸附性能。结果表明,毒死蜱在活性炭上的吸附行为符合Freundlich方程。改性后的活性炭对水中毒死蜱的吸附量显著提高,与改性前相比,三种改性活性炭对有机物的吸附量分别提高了1.0、1.1、2.5倍,三种改性活性炭对毒死蜱吸附能力大小顺序为C-TBAB>C-HTAB>C-HPB,并且酸性条件有利于吸附的进行。

Activated carbon has strong absorption to various esticides due to its porous structure. The surfactant-modified activated carbon was synthesized： Surfactant is referred as quaternary ammonium cation surfactant including hexadecyl trimethyl ammonium bromide （HTAB）, hexadecylpyridinium bromide （HPB） and tetrabutyl ammonium bromide （TBAB）. The adsorbent samples were characterized by specific surface area measurements, elemental analysis and energy dispersive X-Ray spectroscopy （EDX） analyses. The results showed that the sorption isotherm of chlorpyrifos to surfaetant-modified active carbon could be well simulated by Freundlich Equation. Modified activated carbon could effectively adsorb organic pollutant chloropyrifos from water. Compared with unmodified activated carbon, the adsorption capabilities of three modified activated carbon increased by 1.0, 1.1 and 2.5 times, respectively. Moreover, their adsorption capacity was in the order of C-TBAB〉 C-HTAB〉C-HPB. Acidity was beneficial for adsorbing chloropyrifos.