阳-非离子混合表面活性剂对沉积物吸附硝基苯的影响

Adsorption of Cation-nonionic Mixed Surfactants onto Sediment and Their Effects on Adsorption of Nitrobenzene from Water

研究了非离子表面活性剂TritonX 10 0、阳离子表面活性剂氯化十六烷基吡啶 (CPC)及其混合物在沉积物上的吸附行为 ,探讨了它们对沉积物吸附硝基苯的影响 .结果表明 ,CPC和TritonX 10 0在沉积物上的吸附等温线均为非线性 ,吸附量随着平衡浓度的增加急剧增加 ,并迅速达到最大吸附量 .低浓度CPC能明显增加TritonX 10 0在沉积物上的吸附 ,而高浓度的CPC则显著降低TritonX 10 0在沉积物上的吸附 .TritonX 10 0略微降低CPC在沉积物上的吸附 .在表面活性剂浓度较低的实际环境中 ,无论是阳离子或非离子表面活性剂 ,将主要被土壤或沉积物吸附并固定 .硝基苯在沉积物上的吸附等温线为线性 .CPC和TritonX 10 0促进沉积物对硝基苯的吸附 ,CPC TritonX 10 0混合表面活性剂溶液能进一步增强沉积物对硝基苯的吸附 .因此 ,阳离子和非离子混合表面活性剂可增强土壤或沉积物对有机污染物的吸附固定能力 ,也可以用来制备有机膨润土以提高其吸附处理废水的性能 .

Adsorption behaviors of nitrobenzene, a nonionic surfactant(Triton X-100), a cation surfactant(CPC) and their mixture onto a sediment were investigated. The adsorption of Triton X-100 onto the sediment is enhanced with increasing of co-existed CPC at relatively low concentrations but decreased at relatively high concentrations. The adsorption of CPC onto the sediment decreased a little with increasing of co-existed Triton X-100. In natural waters, cation surfactants and nonionic surfactants will be largely adsorbed by soils or sediments. The adsorption of nitrobenzene onto sediment is linear and enhanced by the co-existed Triton X-100 or CPC, and will be significantly enhanced by the mixture of CPC-Triton X-100. Therefore, cation-nonionic mixed surfactants are potentially used to enhance adsorption of organic contaminants onto soils or sediments and to prepare organobentonite for improving their performance in wastewater treatment.